Jump to:

Peer-reviewed articles

2017

Ngo,W., Srinivasan,S., Keech,A., Keir,N., Jones,L. Self versus examiner administration of the Ocular Surface Disease Index©. Journal of Optometry 2017;10,1:34-42. [ Show Abstract ]

Purpose To compare the difference in Ocular Surface Disease Index© (OSDI) scores when participants were given the OSDI to complete on their own (self-guided, SG), versus under the guidance of the examiner (examiner-guided, EG). Methods 100 participants enrolled in this prospective two-visit study (fifty under-45 years old, 38F/12M; and fifty 45 years-and-older, 42F/8M). Participants who scored =1 on the Subjective Evaluation of Symptoms of Dryness (SESoD) were included in this study. Participants completed the OSDI SG during the first visit. Participants returned the next day and repeated the OSDI, but with EG (with standardized instructions). Participants were under deception and believed that they were comparing the OSDI to the SESoD. Results The mean OSDI score of the SG and EG administration was 32.0 ± 17.3 and 33.8 ± 19.6 respectively (p > 0.05) with 95% limits of agreement between -20.6 and +24.2. The correlation between SG and EG administration was Spearman's r = 0.81, p 0.05) for both the under-45 group, and 45-and-older group. The 95% limits of agreement for the under-45 group were smaller than the 45-and-older group (under-45: [-15.5, +13.1,], 45-and-older: [-23.3, +32.2]). A significant difference was found between 8 of the 12 questions items (all p = 0.01). However, the mean difference for each was <0.6 and was not considered to be clinically significant. Conclusion There was no clinically significant difference in OSDI score between SG and EG administration, however having instructions provided with EG administration affected variability of scores in the older group more than the younger group. © 2016 Spanish General Council of Optometry

Ngo,W., Srinivasan,S., Houtman,D., Jones,L. The relief of dry eye signs and symptoms using a combination of lubricants, lid hygiene and ocular nutraceuticals. Journal of Optometry 2017;10,1:26-33. [ Show Abstract ]

Purpose To determine the combined effect of TheraTears® Lubricant Eye Drops, TheraTears® SteriLid Eyelid Cleanser, and TheraTears® Nutrition on dry eye signs and symptoms. Methods This prospective study enrolled 28 dry eye participants. Participants were instructed to use the Lubricant Eye Drops at least 2–4× a day, SteriLid 1–2× a day, and Nutrition 3 gel caps once a day. Participants were followed up at baseline, 1 month and 3 months. Outcome variables were the Ocular Surface Disease Index (OSDI), Symptom Assessment iN Dry Eye (SANDE) questionnaire, non-invasive tear break-up time (NIBUT), osmolarity, number of meibomian glands blocked (#MG blocked), meibum quality, eyelid margin features, Schirmer's test, tear film lipid layer thickness (LLT), meniscus height, corneal and conjunctival staining. Results Twenty participants (mean age = 43, from 23 to 66, 17F, 3M) completed the study. Participants reported having used, on average, the Lubricant Eye Drop 2.4×/day, the SteriLid 1.1×/day, and the Nutrition 3 gel caps 1×/day. There was a significant change over time (p < 0.05) for OSDI (-21.2 points), SANDE (-32.4 points), NIBUT (+0.43 s), eyelid margin features (-1.1 grade), meibum quality (-1.0 grade), and #MG blocked (-4.0 glands). Conclusion By using a combination of TheraTears® Lubricant Eye Drop, SteriLid, and Nutrition, patients experience significant relief in both dry eye symptoms and signs. © 2016 Spanish General Council of Optometry

2016

Walther,H., Subbaraman,L., Jones,L. W. In vitro cholesterol deposition on daily disposable contact lens materials. Optometry and Vision Science 2016;93,1:36-41. [ Show Abstract ]

Purpose. The goal of this study was to analyze how various incubation times affect the uptake of cholesterol on silicone hydrogel (SH) and conventional hydrogel (CH) daily disposable (DD) contact lens materials using an in vitro radiochemical detectionmethod. Methods. Three SH (somofilcon A, delefilcon A, and narafilcon A) and four CH (etafilcon A, nesofilcon A, ocufilcon A, and nelfilcon A) contact lenses were incubated in an artificial tear solution that contained major tear film components and a portion of radioactive 14C-cholesterol. Lenses (N = 4) were incubated for four incubation times (2, 6, 12, or 16 h) to assess the effects on cholesterol deposition. Subsequent to the incubation, the lenses were extracted using 2:1 chloroform:methanol, and the extracts were analyzed in a beta counter and (in nanograms per lens) extrapolated from standard curves. Results. In general, cholesterol deposited statistically significantly more on SH lenses than CHs (p e 0.033), with the exception of somofilcon A and nesolfilcon A materials (p = 0.067). Within the SH materials, narafilcon A accumulated the largest quantity of cholesterol (p G 0.05) and somofilcon A the lowest (p G 0.05). The uptake of cholesterol ranged from 22.63 T 2.98 ng/lens to 97.94 T 4.18 ng/lens for all lens materials. The accumulation of cholesterol was shown to be continuous throughout the 16 h of incubation, without reaching a plateau (p G 0.001). Conclusions. For the periods thatDDlens materials are worn, cholesterol deposits significantlymore ontoSHcontact lenses than CHs. This could have implications for wearers who have higher levels of lipid in their tears that are fitted with SH DD materials. Copyright © American Academy of Optometry.

Jones,L. W., Byrne,M., Ciolino,J. B., Legerton,J., Markoulli,M., Papas,E., Subbaraman,L. Revolutionary future uses of contact lenses. Optometry and Vision Science 2016;93,4:325-327.

Phan,C. -M, Walther,H., Gao,H., Rossy,J., Subbaraman,L. N., Jones,L. Development of an in Vitro ocular platform to test contact lenses. Journal of Visualized Experiments 2016;2016,110:e53907. [ Show Abstract ]

Currently, in vitro evaluations of contact lenses (CLs) for drug delivery are typically performed in large volume vials,1-6 which fail to mimic physiological tear volumes.7 The traditional model also lacks the natural tear flow component and the blinking reflex, both of which are defining factors of the ocular environment. The development of a novel model is described in this study, which consists of a unique 2-piece design, eyeball and eyelid piece, capable of mimicking physiological tear volume. The models are created from 3-D printed molds (Polytetrafluoroethylene or Teflon molds), which can be used to generate eye models from various polymers, such as polydimethylsiloxane (PDMS) and agar. Further modifications to the eye pieces, such as the integration of an explanted human or animal cornea or human corneal construct, will permit for more complex in vitro ocular studies. A commercial microfluidic syringe pump is integrated with the platform to emulate physiological tear secretion. Air exposure and mechanical wear are achieved using two mechanical actuators, of which one moves the eyelid piece laterally, and the other moves the eyeballeyepiece circularly. The model has been used to evaluate CLs for drug delivery and deposition of tear components on CLs.

Phan,C. -M, Subbaraman,L., Jones,L. W. The use of contact lenses as biosensors. Optometry and Vision Science 2016;93,4:419-425. [ Show Abstract ]

The tear film is a complex multilayer film consisting of various proteins, enzymes, and lipids and can express a number of biomarkers in cases of disease. The development of a contact lens sensor presents a noninvasive alternative for the detection and management of various diseases. Recent work has resulted in the commercialization of a device to monitor intraocular pressure for up to 24 h, and there are extensive efforts underway to develop a contact lens sensor capable of continuous glucose tear film monitoring to manage diabetes. This clinical perspective will highlight the major developments within this field and list some of the major challenges that still need to be addressed. © 2015 American Academy of Optometry.

Phan,C. -M, Bajgrowicz,M., Gao,H., Subbaraman,L. N., Jones,L. W. Release of fluconazole from contact lenses using a novel in vitro eye model. Optometry and Vision Science 2016;93,4:387-394. [ Show Abstract ]

Purpose. Rapid drug release followed by a plateau phase is a common observation with drug delivery from contact lenses (CLs) when evaluated in a vial. The aim of this study was to compare the release of fluconazole from seven commercially available daily disposable CLs using a conventional vial-based method with a novel in vitro eye model. Methods. An eye model was created using two 3-dimensional printed molds, which were filled with polydimethylsiloxane to obtain an inexpensive model that would mimic the eyeball and eyelid. The model was integrated with a microfluidic syringe pump, and the flow-through was collected in a 12-well microliter plate. Four commercial daily disposable conventional hydrogels (nelfilcon A, omafilcon A, etafilcon A, ocufilcon B) and three silicone hydrogels (somofilcon A, narafilcon A, delefilcon A) were evaluated. These CLs were incubated with fluconazole for 24 h. The drug release was measured in a vial containing 4.8 mL of phosphate-buffered saline and in the polydimethylsiloxane eye model with a 4.8-mL tear flow across 24 h. Results. Overall, conventional hydrogel CLs had a higher uptake and release of fluconazole than silicone hydrogel CLs (p < 0.05). A higher drug release was observed in the vial condition compared with the eye model (p < 0.001). In the vial system, the drugs were rapidly released from the CL within the first 2 h, followed by a plateau phase. In contrast, drug release in the eye model under low tear volume was sustained and did not reach a plateau across 24 h (p < 0.05). Conclusions. Rapid drug release results from using a vial as the release system. Under low tear volume at physiological tear flow, commercial CLs can maintain a sustained drug release profile for up to 24 h. However, eyes with fungal keratitis may have increased tearing, which would significantly accelerate drug release. © 2015 American Academy of Optometry.

Liu,L. Y., Seo,J., McCanna,D. J., Subbaraman,L. N., Jones,L. W. Assessment of biofilm formation of E. meningoseptica, D. acidovorans, and S. maltophilia in lens cases and their growth on recovery media. Contact Lens and Anterior Eye 2016;39,2:117-123. [ Show Abstract ]

Purpose: Bacterial biofilm formation in contact lens cases is a risk factor in the development of both microbial and infiltrative keratitis. This investigation evaluated three emerging pathogens: Stenotrophomonas maltophilia, Elizabethkingia meningoseptica, and Delftia acidovorans for biofilm formation and metabolic activity in lens cases. Also, growth of these bacteria on different media was assessed to optimize recovery conditions. Methods: The three bacteria were incubated in lens cases with different concentrations of tryptic soy broth. Biofilm formation was evaluated by measuring metabolic activity using MTT and enumerating the number of viable bacteria. To determine the optimal recovery media, dilutions of these microorganisms were plated on six different media. The number of colony forming units (CFU) was recorded after 48, 72, and 96 h of incubation at 32 °C and 37 °C for S. maltophilia, and at 37 °C for E. meningoseptica and D. acidovorans. Results: All three microorganisms established biofilms in the lens cases, with significant numbers of CFU recovered. Biofilms of S. maltophilia and E. meningoseptica were metabolically active. Significant reduction in metabolic activity and number of viable S. maltophilia occurred when the incubation temperature was raised from 32 °C to 37 °C (p < 0.05). The metabolic activity of the biofilms increased with greater organic load present. The highest percent recovery for all three organisms was given by Columbia blood agar, followed by chocolate. Conclusion: Based on the results, the presence of the three emerging pathogens present in lens cases and from corneal isolates can be accurately determined if proper growth media and incubation temperatures are utilized.

Hall,B., Heynen,M., Jones,L. W., Forrest,J. A. Analysis of Using I125 Radiolabeling for Quantifying Protein on Contact Lenses. Current eye research 2016;41,4:456-465. [ Show Abstract ]

Purpose: To investigate the accuracy of I125 radiolabeling to quantitatively determine the deposition of protein onto various commercially available contact lens (CL) materials. Methods: Commercially available silicone hydrogel and conventional hydrogel CL materials were examined for times ranging from 10 s to 1 week. Adsorption of free I125 was measured directly for the CL. The use of dialyzing labeled proteins and/or using NaI to compete with free I125 uptake was investigated as ways to minimize effects due to free I125. Results: At all time points and with all lens materials, there was 0.3 µg/lens or greater of apparent mass attributable to free I125 uptake. Dialyzing labeled proteins significantly reduced free I125 uptake for all materials investigated. The benefit of using dialyzed protein was most prominent at shorter times, as free I125 is continuously generated over time. Using NaI can reduce free I125 uptake for some lens materials, but this is shown to directly affect protein deposition on some materials. Conclusions: Periodic replenishment of incubation solutions with freshly dialyzed labeled protein to limit free I125 generation is recommended, but the incorporation of NaI onto the buffer solution is not. Irrespective of the exact procedure to limit free I125 uptake, extra steps must be performed to quantify the amount of I125 adsorbed onto contact lens materials, to determine thresholds of confidence with respect to the actual protein deposition that occurs.

Moezzi,A. M., Varikooty,J., Schulze,M., Ngo,W., Lorenz,K. O., Boree,D., Jones,L. W. Corneal Swelling with Cosmetic etafilcon A Lenses versus No Lens Wear. Optometry and Vision Science 2016;93,6:619-628. [ Show Abstract ]

Purpose: To determine if the use of pigments or adding polyvinyl pyrrolidone during the fabrication of 1-DAY ACUVUE DEFINE (AD) brand contact lenses impacts open-eye corneal swelling compared with no lens wear (NLW). Methods: A partial double-masked, randomized, bilateral crossover study was conducted in 24 Asian subjects using AD, 1-DAY ACUVUE DEFINE with Lacreon (ADL), NLW, and a control lens with no tint (1-DAY ACUVUE MOIST [AM]). Central corneal thickness was measured before insertion and immediately after removal after 8 ± 1 h of open-eye wear using an optical pachymeter in one eye. Corneal thickness along a 10-mm cord was measured in the contralateral eye using the Visante optical coherence tomographer (OCT). Corneal swelling was tested for noninferiority using a 5% margin. The endothelial bleb response was measured at baseline and 20 min after lens insertion using specular microscopy. Subjective grading of corneal staining and limbal/bulbar hyperemia were also monitored. Results: After 8 ± 1 h of open-eye wear, central corneal swelling across the study lenses with either optical pachymeter or OCT methods was negligible. Peripheral corneal swelling least-square mean differences with OCT were -0.03% (95% confidence interval [95% CI], -0.65 to 0.58%) and -0.26% (95% CI, -0.87 to 0.36%) between AD and ADL and the control lens (AM), respectively, and 1.67% (95% CI, 1.06 to 2.29%) and 1.45% (95% CI, 0.84 to 2.06%) between AD and ADL and NLW, respectively. No endothelial blebs were observed. No clinically significant differences were distinguished between the lenses and NLW for corneal staining and limbal/bulbar hyperemia. Conclusions: After 8 ± 1 h of open-eye wear, central and peripheral corneal swelling along the horizontal meridian with AD, ADL, AM, and NLW were equivalent. These results confirm that the addition of polyvinyl pyrrolidone or pigments to etafilcon A to obtain a limbal ring design have no impact on corneal swelling or limbal/bulbar hyperemia during normal open-eye wear.

Verma,M. S., Wei,S. -C, Rogowski,J. L., Tsuji,J. M., Chen,P. Z., Lin,C. -W, Jones,L., Gu,F. X. Interactions between bacterial surface and nanoparticles govern the performance of "chemical nose" biosensors. Biosensors and Bioelectronics 2016;83115-125. [ Show Abstract ]

Rapid and portable diagnosis of pathogenic bacteria can save lives lost from infectious diseases. Biosensors based on a "chemical nose" approach are attracting interest because they are versatile but the governing interactions between bacteria and the biosensors are poorly understood. Here, we use a "chemical nose" biosensor based on gold nanoparticles to explore the role of extracellular polymeric substances in bacteria-nanoparticle interactions. We employ simulations using Maxwell-Garnett theory to show how the type and extent of aggregation of nanoparticles influence their colorimetric response to bacteria. Using eight different species of Gram-positive and Gram-negative bacteria, we demonstrate that this "chemical nose" can detect and identify bacteria over two orders of magnitude of concentration (89% accuracy). Additionally, the "chemical nose" differentiates between binary and tertiary mixtures of the three most common hospital-isolated pathogens: Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa (100% accuracy). We demonstrate that the complex interactions between nanoparticles and bacterial surface determine the colorimetric response of gold nanoparticles and thus, govern the performance of "chemical nose" biosensors. © 2016 Elsevier B.V.

Ng,A., Evans,K., North,R. V., Jones,L., Purslow,C. Impact of Eye Cosmetics on the Eye, Adnexa, and Ocular Surface. Eye and Contact Lens 2016;42,4:211-220. [ Show Abstract ]

Despite the fact that cosmetic products undergo rigorous testing to ensure they are safe for human use, some users report mild discomfort following their application. The cutaneous changes, such as allergic dermatitis, are well reported, but the ocular changes associated with eye cosmetic use are less so. Some pigmented cosmetic products may accumulate within the lacrimal system and conjunctivae over many years of use, but immediate reports of eye discomfort after application are most common. Changes to the tear film and its stability may occur shortly after application, and contact lens wearers can also be affected by lens spoliation from cosmetic products. Additionally, creams used in the prevention of skin aging are often applied around the eyes, and retinoids present in these formulations can have negative effects on meibomian gland function and may be a contributing factor to dry eye disease. The aim of this review is to summarize current knowledge regarding the impact of cosmetic products on the eye, ocular surface, and tear film. © 2015 Contact Lens Association of Ophthalmologists.

Dantam,J., McCanna,D. J., Subbaraman,L. N., Papinski,D., Lakkis,C., Mirza,A., Berntsen,D. A., Morgan,P., Nichols,J. J., Jones,L. W., Mathew,J. H., Cox,S. M., Bickle,K. M., Powell,D. R., Cox,J., Miller,W. L., Wallace-Tucker,A., Charrier,S., Chen,Y. -J, Cardenas,L., Huerta,S., Dionne,K., Maldonado-Codina,C., Plowright,A. J., Howarth,G. F., Chatterjee,N., Smith,S., Dumbleton,K., Schulze,M., Moezzi,A., Luensmann,D., Ngo,W., Paquette,L., Srinivasan,S., Varikooty,J., Johnson,J., Simpson,M., Voss,L., R Microbial contamination of contact lens storage cases during daily wear use. Optometry and Vision Science 2016;93,8:925-932. [ Show Abstract ]

Purpose. To evaluate contact lens (CL) storage case contamination when used with four different CL care solutions during daily wear of three different CL materials. Methods. A parallel, prospective, bilateral, randomized clinical trial (n = 38) was conducted. Subjects were randomly assigned to use one of three CL materials (etafilcon A, senofilcon A, or galyfilcon A) on a daily wear basis. Subsequently, each subject randomly used one of four different CL care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and CLEAR CARE) for 2 weeks, along with their respective storage cases. After every 2-week period, their storage cases were collected and the right and left wells of each storage case were randomized for two procedures: (1) microbial enumeration by swabbing the storage case surface and (2) evaluation of biofilm formation (multipurpose solution cases only) using a crystal violet staining assay. Results. More than 80% of storage cases were contaminated when used in conjunction with the four CL care solutions, irrespective of the CL material worn. Storage cases maintained with CLEAR CARE (mean Log colony forming units (CFU)/ well ± SD, 2.0 ± 1.0) revealed significantly (p < 0.001) greater levels of contamination, compared to those maintained with Biotrue (1.3 ± 0.8) and RevitaLens OcuTec (1.2 ± 0.8). Predominantly, storage cases were contaminated with Gram-positive bacteria (= 80%). There were significant differences (p = 0.013) for the levels of Gram-negative bacteria recovered from the storage cases maintained with different CL care solutions. Storage cases maintained withOPTI-FREE PureMoist (0.526 ± 0.629) showed significantly higher biofilm formation (p = 0.028) compared to those maintained with Biotrue (0.263 ± 0.197). Conclusions. Levels of contamination ranged from 0 to 6.4 Log CFU/storage case well, which varied significantly (p < 0.001) between different CL care solutions, and storage case contamination was not modulated by CL materials. © Copyright 2016 American Academy of Optometry.

Berntsen,D. A., Hickson-Curran,S. B., Jones,L. W., Mathew,J. H., Maldonado-Codina,C., Morgan,P. B., Schulze,M. M., Nichols,J. J., Cox,S. M., Bickle,K. M., Powell,D. R., Cox,J., Miller,W. L., Wallace-Tucker,A., Charrier,S., Chen,Y. -J, Cardenas,L., Huerta,S., Dionne,K., Plowright,A. J., Howarth,G. F., Chatterjee,N., Mirza,A., Smith,S., Dumbleton,K., Moezzi,A. M., Luensmann,D., Ngo,W., Paquette,L., Srinivasan,S., Varikooty,J., Johnson,J., Simpson,M., Voss,L., Ryan,L., Careless,N., Smith,A., Subbar Subjective comfort and physiology with modern contact lens care products. Optometry and Vision Science 2016;93,8:809-819. [ Show Abstract ]

Purpose. To compare subjective comfort and ocular physiology with three multipurpose solutions (MPSs) to that of a peroxide-based system with three different soft contact lens materials. Methods. Habitual soft contact lens wearers (n = 236) were enrolled at three sites and completed a washout period with no contact lens solution for =4 days. Subjects were randomly assigned to one of three lens types: etafilcon A, galyfilcon A, or senofilcon A. A new lens of the assigned type was worn for 10 to 14 days each while using one of four care solutions, in random order (A - polyaminopropyl biguanide + polyquaternium, B - POLYQUAD + Aldox, C - alexidine + polyquaternium-1, and D - hydrogen peroxide) with a washout period (=4 days) between each solution. After each care solution, biomicroscopy was performed and subjective comfort was assessed using the Contact Lens User Experience (CLUE) questionnaire and other instruments including comfortable wear time (CWT). Linear mixed models were used for analysis. Comfort and biomicroscopy signs with each MPS were compared to that of the peroxide solution. Results. Subjective CLUE Comfort score across all lens types with each MPS was not significantly different than with the peroxide solution (p = 0.98). There were no differences in CWT between each MPS and the peroxide solution for any lens type (range of differences: -0.8 to 0.8 h; all p = 0.13). Six MPS/material combinations had no clinically meaningful change in corneal staining versus peroxide (<0.5 units); three combinations could increase staining by up to 0.57 units. Staining was

Schulze,M. -M, Srinivasan,S., Hickson-Curran,S. B., Berntsen,D. A., Howarth,G. F., Toubouti,Y., Morgan,P., Nichols,J. J., Jones,L. W., Mathew,J. H., Cox,S. M., Bickle,K. M., Powell,D. R., Cox,J., Miller,W. L., Wallace-Tucker,A., Charrier,S., Chen,Y. -J, Cardenas,L., Huerta,S., Dionne,K., Maldonado-Codina,C., Plowright,A. J., Chatterjee,N., Mirza,A., Smith,S., Dumbleton,K., Moezzi,A. M., Luensmann,D., Ngo,W., Paquette,L., Varikooty,J., Johnson,J., Simpson,M., Voss,L., Ryan,L., Careless,N., Smith, Lid wiper epitheliopathy in soft contact lens wearers. Optometry and Vision Science 2016;93,8:943-954. [ Show Abstract ]

Purpose. To evaluate lid wiper epitheliopathy (LWE) in soft contact lens (SCL) wearers on initial presentation and after using various SCL and solution combinations. Methods. LWE was assessed in 253 habitual SCL wearers who attended a screening visit at one of three study sites. LWE was assessed using lissamine green and sodium fluorescein dyes (Korb scale); a final LWE grade was calculated as the averaged LWE grade of the two dyes. Eligible habitual wearers continued into the four study periods, during which they wore one of three SCL types (etafilcon A, galyfilcon A, or senofilcon A) while using each of four care solutions for 10 to 14 days in randomized order. Statistical analyses were performed using linear mixed models, testing for differences in LWE for subject characteristics and between three multipurpose (MPS) test solutions (BioTrue, OPTI-FREE PureMoist, RevitaLens OcuTec) compared to a hydrogen peroxide (Clear Care) control solution. Results. LWE was present in 85% of habitual SCL wearers. LWE was not different for age (p = 0.28), sex (p = 0.99), race (p = 0.34), and comfort (p = 0.38) and not correlated with refractive error (r = 0.07). LWE was lower in habitual senofilcon A wearers (least-squares (LS) mean ± SE = 0.82 ± 0.19) compared to wearers of lotrafilcon B (1.34 ± 0.20; p < 0.02), comfilcon A (1.41 ± 0.21; p < 0.01), and other (1.18 ± 0.16; p < 0.03). Two hundred three participants completed all four study solutions with their assigned lens type; LWE was not different between the MPSs compared to the peroxide control solution across lens materials, except for less LWE for BioTrue (0.88 ± 0.17) versus Clear Care for participants wearing galyfilcon A (1.11 ± 0.18; p < 0.01). Conclusions. On initial presentation, LWE was present in 85% of habitual wearers and found to be independent of age, sex, race, comfort, and refractive error but dependent on habitual SCL type. There were no clinically meaningful differences in LWE between the MPSs and hydrogen peroxide solution for the three lens types studied. © Copyright 2016 American Academy of Optometry.

Cox,S. M., Berntsen,D. A., Chatterjee,N., Hickson-Curran,S. B., Jones,L. W., Moezzi,A. M., Morgan,P. B., Nichols,J. J., Mathew,J. H., Bickle,K. M., Powell,D. R., Cox,J., Miller,W. L., Wallace-Tucker,A., Charrier,S., Chen,Y. -J, Cardenas,L., Huerta,S., Dionne,K., Maldonado-Codina,C., Plowright,A. J., Howarth,G. F., Mirza,A., Smith,S., Dumbleton,K., Schulze,M., Luensmann,D., Ngo,W., Paquette,L., Srinivasan,S., Varikooty,J., Johnson,J., Simpson,M., Voss,L., Ryan,L., Careless,N., Smith,A., Subbarama Eyelid margin and meibomian gland characteristics and symptoms in lens wearers. Optometry and Vision Science 2016;93,8:901-908. [ Show Abstract ]

Purpose. To describe the lid margin characteristics of contact lens wearers and relate them to comfort during lens wear. Methods. Three study sites enrolled habitual contact lens wearers. Subjects completed the Comfort domain of the Contact Lens User Experience (CLUE) questionnaire, and each eye was graded for the presence of mucocutaneous junction (MCJ) displacement, lid margin irregularity, and lid margin vascularity. Examiners counted the number of meibomian gland (MG) orifices in the central centimeter of the lower eyelid and the number of those that showed pouting/plugging and vascular invasion. MG expressibility was graded according to the Shimazaki schema. Subjects were grouped based on presence/ absence of each characteristic, total number of orifices (=5 vs. 0). Descriptive statistics are reported. A linear model was used to assess the fixed effect of each characteristic on combined CLUE score and each CLUE statement, if the effect on combined CLUE score showed p < 0.10. Results. The study included 203 subjects (67.5% female) with mean age (±SD) of 30.3 ± 9.6 years. The most commonly observed characteristics were orifice pouting/plugging, compromised MG expressibility, and lid margin vascularity (35.0, 30.3, and 20.4%, respectively). MCJ displacement and MG expressibility had an effect on the combined CLUE score such that individual CLUE statements were analyzed (p = 0.01 and p = 0.06, respectively). MCJ displacement had an effect on comfort upon insertion (p = 0.01), comfort after 5 minutes (p = 0.03), end-of-day comfort (p = 0.01), and ability to maintain ocular moisture (p = 0.030). MG expressibility had a significant effect on general comfort (p = 0.01), comfort throughout the day (p = 0.02), and the ability to maintain ocular moisture (p = 0.02). Conclusions. MCJ displacement and MG expressibility have an effect on contact lens comfort. © Copyright 2016 American Academy of Optometry.

Omali,N. B., Heynen,M., Subbaraman,L. N., Papinski,D., Lakkis,C., Smith,S. L., Morgan,P. B., Berntsen,D. A., Nichols,J. J., Jones,L. W., Mathew,J. H., Cox,S. M., Bickle,K. M., Powell,D. R., Cox,J., Miller,W. L., Wallace-Tucker,A., Charrier,S., Chen,Y. -J, Cardenas,L., Huerta,S., Dionne,K., Maldonado-Codina,C., Plowright,A. J., Howarth,G. F., Chatterjee,N., Mirza,A., Dumbleton,K., Schulze,M., Moezzi,A. M., Luensmann,D., Ngo,W., Paquette,L., Srinivasan,S., Varikooty,J., Johnson,J., Simpson,M., Vos Impact of lens care solutions on protein deposition on soft contact lenses. Optometry and Vision Science 2016;93,8:963-972. [ Show Abstract ]

Purpose. To evaluate the effect of four contemporary lens care solutions on total protein, total lysozyme, and active lysozyme extracted from three contact lens materials. Methods. Adapted contact lens wearers were recruited at three sites, and all subjects were randomly assigned to daily wear of either etafilcon A, galyfilcon A, or senofilcon A for 2 weeks. Four lens care solutions (Biotrue, OPTI-FREE PureMoist, RevitaLens OcuTec, and ClearCare) were used by each subject in random order with a new pair of lenses after a washout period between solutions of at least 4 days. After 2 weeks of daily wear, contact lenses were collected for analysis. Proteins were extracted from a subset of contact lenses (n = 568) and total protein, total lysozyme, and lysozyme activity were quantified using a modified Bradford assay, an enzyme-linked immunosorbent assay, and a micrococcal assay, respectively. Results. Higher levels of total protein were extracted from etafilcon A when used with Biotrue compared to other solutions (p = 0.0001). There were higher levels of total lysozyme extracted from galyfilcon A lenses when used with PureMoist than with Biotrue or Clear Care (p < 0.006). Higher total lysozyme was extracted from senofilcon A when used with RevitaLens OcuTec compared to Biotrue (p = 0.002). Lower lysozyme activity was recovered from senofilcon A lenses with RevitaLens OcuTec when compared to all other care solutions (all p < 0.004). When Biotrue, PureMoist, or RevitaLens OcuTec were used, higher total lysozyme was extracted from galyfilcon A compared to senofilcon A(p < 0.01). When RevitaLens OcuTec was used, higher levels of active lysozyme were extracted from galyfilcon A compared to senofilcon A (p = 0.02). Conclusions. The ability of lens care solutions to remove protein from lenses varies depending upon the care solution composition and also the polymeric make-up of the contact lens material. © Copyright 2016 American Academy of Optometry.

Caffery,B., Dogru,M., Jones,L. W., Lin,M. C., Nichols,J. J., Papas,E., Pucker,A., Pult,H., Willcox,M. D. P. Contact lens comfort. Optometry and Vision Science 2016;93,8:790-792.

Stahl,U., Keir,N. J., Landers,A., Jones,L. W. Effect of short recovery periods on ocular comfort during daily lens wear. Optometry and Vision Science 2016;93,8:861-871. [ Show Abstract ]

Purpose. To assess the impact of lens-free intervals of varying lengths on end-of-day comfort with soft contact lenses. Methods. Twenty-five symptomatic lens wearers participated in this randomized, cross-over study involving nine individual 12-hour days: one spectacle (no lens) and eight lens wear days. On each lens wear day, lenses were worn bilaterally in 2-hour intervals, separated by lens-free (recovery) periods of 0, 30, 60, or 80 minutes (repeated throughout the day). For each 2-hour lens wear interval, new lenses were worn. Ocular comfort was rated on a 0 to 100 visual analogue scale (0 = extremely uncomfortable); tear film and ocular parameters were assessed at the beginning and end of each study day. This study involved two different types of silicone hydrogel lenses, and the order of lens type and length of recovery period was randomized. Participants were unaware of the true study purpose and that a new lens pair was used for each lens wear interval. Results. End-of-day comfort on lens wear days was significantly worse than on the spectacle day (p 0.05). Although lens wear affected noninvasive tear film break-up time and conjunctival staining, there were no effects of recovery period length on noninvasive tear film break-up time (p > 0.05), tear meniscus height (p > 0.05), corneal staining (p > 0.05), conjunctival staining (p > 0.05), bulbar conjunctival redness (p > 0.05), or limbal redness (p > 0.05). There was no consistent effect of recovery period length on lid margin staining. Conclusions. Lens-free recovery periods during a 12-hour lens wear day did not positively impact end-of-day comfort in this study. Cumulative lens wear times ranged from 8 to 12 hours, and the results suggest that once the length of lens wear exceeds the usual comfortable wear time, there is no benefit of short recovery periods. © Copyright 2016 American Academy of Optometry.

Muntz,A., van Doorn,K., Subbaraman,L. N., Jones,L. W. Impression cytology of the lid wiper area. Journal of Visualized Experiments 2016;2016,114:. [ Show Abstract ]

Few reports on the cellular anatomy of the lid wiper (LW) area of the inner eyelid exist and only one report makes use of cytological methods. The optimization of a method of collecting, staining and imaging cells from the LW region using impression cytology (IC) is described in this study. Cells are collected from the inner surface of the upper eyelid of human subjects using hydrophilic polytetrafluoroethylene (PTFE) membranes, and stained with cytological dyes to reveal the presence of goblet cells, mucins, cell nuclei and various degrees of pre- and parakeratinization. Immunocytochemical dyes show cell esterase activity and compromised cell membranes by the use of a confocal scanning laser microscope. Up to 100 microscopic digital images are captured for each sample and stitched into a high-resolution, large scale image of the entire IC span. We demonstrate a higher sensitivity of IC than reported before, appropriate for identifying cellular morphologies and metabolic activity in the LW area. To our knowledge, this is the first time this selection of fluorescent dyes was used to image LW IC membranes. This protocol will be effective in future studies to reveal undocumented details of the LW area, such as assessing cellular particularities of contact lens wearers or patients with dry eye or lid wiper epitheliopathy. © 2016 Journal of Visualized Experiments.

Verma,M. S., Tsuji,J. M., Hall,B., Chen,P. Z., Forrest,J., Jones,L., Gu,F. X. Towards point-of-care detection of polymicrobial infections: Rapid colorimetric response using a portable spectrophotometer. Sensing and Bio-Sensing Research 2016;1015-19. [ Show Abstract ]

Infectious diseases spread rapidly because current diagnostic methods are slow, expensive, and require technical expertise. Biosensors have recently been used as devices that can be deployed at the point-of-care for rapid and accurate diagnosis. Here, we show that a “chemical nose” biosensor based on gold nanoparticles can be coupled with a portable spectrophotometer to detect monomicrobial and polymicrobial solutions of pathogenic bacteria within 2 min of data collection. The design presented here exploits the rapid kinetics of gold nanoparticle aggregation around bacteria, which leads to a dramatic color change. The “chemical nose” produces unique signals based on the surface characteristics of the bacteria—such as the presence of extracellular polymeric substances, distribution of charged lipids, and localization of proteins—and hence provides a versatile platform for detection. We present a biosensor design that can easily be translated to the point-of-care because of its rapid response and simple output. © 2016 The Authors

Phan,C. -M, Bajgrowicz,M., McCanna,D. J., Subbaraman,L. N., Jones,L. Effects of Antifungal Soaked Silicone Hydrogel Contact Lenses on Candida albicans in an Agar Eye Model. Eye and Contact Lens 2016;42,5:313-317. [ Show Abstract ]

Purpose: To evaluate the effects of two commercial silicone hydrogel contact lenses (CLs) soaked with natamycin (NA) or fluconazole (FL) on the growth of Candida albicans in an in vitro eye model. Methods: Three-D printed molds were used as a cast for making eye-shaped models comprising potato dextrose agar. Senofilcon A (SA) and lotrafilcon B (LB) CLs were incubated with either 2 mL of NA or FL at a concentration of 1 mg/mL for 24 hr. To simulate a fungal infection, the eye models were coated with C. albicans. The drug-soaked lenses were placed on top of the eye models. Seven experimental conditions were examined: (1) NA-SA, (2) NA-LB, (3) FL-SA, (4) FL-LB, (5) SA, (6) LB, and (7) control - no lens. At specified time points (t1, 8, 16, 24, 48 hr), the agar eyes from each experimental condition were removed from the incubator and photographed. The yeast cells from the 24 and 48 hr time point were also analyzed using light microscopy. Results: At 24 and 48 hr, there was considerable growth observed for all conditions except for the NA-SA and NA-LB conditions. When observed under the microscope at 24 and 48 hr, the morphology of the yeast cells in the FL-SA and SA condition were similar to that of the control (oval shaped). There was limited hyphae growth observed for LB and significant visible hyphae growth for the NA-LB group. For NA-SA, NA-LB, and FL-LB groups, the cells were significantly smaller compared with the control. Conclusions: For NA-SA and NA-LB, there was limited growth of C. albicans observed on the eye models even after 48 hr. Under the microscope, the cell morphology differ noticeably between each testing condition, and is dependent on drug-lens combinations. © 2015 Contact Lens Association of Ophthalmologists.

Liu,S., Dozois,M. D., Chang,C. N., Ahmad,A., Ng,D. L. T., Hileeto,D., Liang,H., Reyad,M. -M, Boyd,S., Jones,L. W., Gu,F. X. Prolonged ocular retention of mucoadhesive nanoparticle eye drop formulation enables treatment of eye diseases using significantly reduced dosage. Molecular Pharmaceutics 2016;13,9:2897-2905. [ Show Abstract ]

Eye diseases, such as dry eye syndrome, are commonly treated with eye drop formulations. However, eye drop formulations require frequent dosing with high drug concentrations due to poor ocular surface retention, which leads to poor patient compliance and high risks of side effects. We developed a mucoadhesive nanoparticle eye drop delivery platform to prolong the ocular retention of topical drugs, thus enabling treatment of eye diseases using reduced dosage. Using fluorescent imaging on rabbit eyes, we showed ocular retention of the fluorescent dye delivered through these nanoparticles beyond 24 h while free dyes were mostly cleared from the ocular surface within 3 h after administration. Utilizing the prolonged retention of the nanoparticles, we demonstrated effective treatment of experimentally induced dry eye in mice by delivering cyclosporin A (CsA) bound to this delivery system. The once a week dosing of 0.005 to 0.01% CsA in NP eye drop formulation demonstrated both the elimination of the inflammation signs and the recovery of ocular surface goblet cells after a month. Thrice daily administration of RESTASIS on mice only showed elimination without recovering the ocular surface goblet cells. The mucoadhesive nanoparticle eye drop platform demonstrated prolonged ocular surface retention and effective treatment of dry eye conditions with up to 50- to 100-fold reduction in overall dosage of CsA compared to RESTASIS, which may significantly reduce side effects and, by extending the interdosing interval, improve patient compliance. © 2016 American Chemical Society.

Woods,J., Jones,L. W. Pilot study to determine the effect of lens and eye rinsing on Solution-Induced Corneal Staining (SICS). Optometry and Vision Science 2016;93,10:1218-1227. [ Show Abstract ]

Purpose The main purpose of this study was to determine whether two interventions (rinsing the lens before lens insertion and rinsing the ocular surface post-lens removal) had any impact on solution-induced corneal staining (SICS). In addition, the presence of hyper-reflective epithelial cells in the presence of SICS was investigated. Methods Twenty subjects wore new balafilcon A lenses, which had been soaked overnight in a multipurpose care product containing polyhexamethylene biguanide for 2 hours. The study was conducted across three phases. In phase 1 (investigator and subject masked, randomized eye), one lens was rinsed with nonpreserved saline before lens insertion. In phase 2 (investigator masked, randomized eye), one eye was rinsed with nonpreserved saline after lens removal, before staining assessment. Corneal staining was recorded as the percentage area of the cornea exhibiting superficial punctate staining. In both phases, ocular comfort and presence of specific symptoms were captured. In phase 3, there was no randomized treatment; confocal images of the epithelium were obtained after 2 hours of wear. Results In phase 1 (lens-rinse), there was no significant difference in staining between the treated and untreated eyes (84 vs. 92%, respectively; p = 0.06). In phase 2 (eye-rinse), there was also no significant difference between the treated and untreated eye (86 vs. 86%, p = 0.92). Most subjects were asymptomatic. In phase 3, images of hyper-reflective cells were captured in 97% of the eyes imaged. Conclusions The two rinsing procedures did not affect the level of the SICS response. Hyper-reflective epithelial cells were found to be present in a significant number of eyes exhibiting SICS, and their presence warrants further investigation. © 2016 American Academy of Optometry.

Jones,D., Woods,C., Jones,L., Efron,N., Morgan,P. A sixteen year survey of Canadian contact lens prescribing. Contact Lens and Anterior Eye 2016;39,6:402-410. [ Show Abstract ]

Purpose To understand long-term contact lens prescribing habits of Canadian optometrists. Methods One thousand optometrists were surveyed annually from 2000 to 2015. Information was requested on the first ten patients examined after receiving the survey. Results Over the 16-year survey period, 1987 optometrists provided information on 19,143 patients. Mean age of the patients was 32.7 ± 14.4 years. Ratio of females to males was 2:1, the ratio of new fits to refits was 2:3. Soft contact lenses represented 94.5% of all fits. Rigid lenses were more often used as a refit compared to a new fit. Over the 16 years, market share for silicone hydrogel materials grew from 0% to 69.6%, mid-water content materials declined from 75.7% to 14.1%. The multifocal market share grew at the expense of spherical designs, with no change in toric lens fitting. Monthly soft lens replacement remained the preferred option at 48.2%, followed by daily disposable at 40.8%; two-weekly replacement declined to less than10% of patients by 2015. Extended wear was likely used to refit and only to a small proportion of wearers, representing 2.6% of SCL by 2015. The lens care system of choice throughout the period was multipurpose solutions, although the proportion for peroxide systems more than doubled by 2015 from 9.6%, to 21.1%. Conclusions Over the 16-year period, SCL material preference changed to silicone hydrogels with monthly replacement being preferred; daily disposables replacing 2-weekly as the alternate. Lens care preference continued to be multipurpose solutions. Rigid lenses appear to be sustained for specialist fitting. © 2016 British Contact Lens Association

2015

Muntz,A., Subbaraman,L. N., Sorbara,L., Jones,L. Tear exchange and contact lenses: A review. Journal of Optometry 2015;8,1:2-11. [ Show Abstract ]

Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses.

Liu,S., Chang,C. N., Verma,M. S., Hileeto,D., Muntz,A., Stahl,U., Woods,J., Jones,L. W., Gu,F. X. Phenylboronic acid modified mucoadhesive nanoparticle drug carriers facilitate weekly treatment of experimentallyinduced dry eye syndrome. Nano Research 2015;8,2:621-635.

Varikooty,J., Schulze,M. M., Dumbleton,K., Keir,N., Woods,C. A., Fonn,D., Jones,L. W. Clinical performance of three silicone hydrogel daily disposable lenses. Optometry and Vision Science 2015;92,3:301-311. [ Show Abstract ]

Purpose. To determine the clinical performance of DAILIES TOTAL1 (DT1), Clariti 1Day (C1D), and 1-DAY ACUVUE TruEye (AVTE) silicone hydrogel daily disposable contact lenses (SiHy DDCLs). Methods. Eligible participants, subdivided into asymptomatic and symptomatic groups, wore each SiHy DDCLs for three consecutive days. Each participant attended three visits (on day 1 at 0 hours; on days 1 and 3 after 8 hours ofwear) per lens type. The order of lens wear was randomized, with at least 1 day washout between lenses. Lens-related performance was evaluated by assessing lens surface deposits, wettability, pre-lens noninvasive tear breakup time, lens movement, and centration; ocular response assessments included conjunctival redness, corneal staining, and conjunctival staining and indentation. Results. Fifty-one asymptomatic and 53 symptomatic participantscompleted the study. For all visits, themeannoninvasive tear breakup timewas about 1 second longer withDT1 than withC1DandAVTE (p < 0.01).Overall, thewettability of all three lenses was good; however, DT1 was graded marginally better than the other lenses (both p < 0.01). On day 3, eyes wearing AVTE had significantly more dehydration-induced corneal staining compared with DT1 (AVTE, 24%; DT1, 11%; p < 0.01). After 8 hours, conjunctival staining was different between lenses (greatest with C1D and least with DT1; all p < 0.01). Conjunctival indentation was more prevalent with the C1D lenses (n = 70) compared with DT1 (n = 1; p < 0.01) and AVTE (n = 11; p < 0.01). Therewere no differences between asymptomatic and symptomatic lenswearers for any of the clinical parameters (all p 9 0.05). Conclusions. Each of the three SiHy DDCLs performed well. Noninvasive tear breakup time was longest and wettability was greater with DT1. C1D had the most conjunctival staining conjunctival indentation. There was no difference between asymptomatic and symptomatic wearers with regard to ocular response and contact lensYrelated parameters. These results suggest that SiHy DDCLs may be an excellent contact lens modality for the symptomatic patient.

Chang,J. M. L., McCanna,D. J., Subbaraman,L. N., Jones,L. W. Efficacy of antimicrobials against biofilms of achromobacter and pseudomonas. Optometry and Vision Science 2015;92,4:506-513. [ Show Abstract ]

Purpose. Achromobacter xylosoxidans and Pseudomonas aeruginosa biofilms can develop in ophthalmic products and accessories such as contact lens cases, leading to the development of ocular infections. This study evaluated the efficacy of the antimicrobials polyaminopropyl biguanide (PAPB) and benzalkonium chloride (BAK) against A. xylosoxidans and P. aeruginosa biofilms. Methods. Biofilms of A. xylosoxidans and P. aeruginosa used as a comparative control were formed by incubating the bacteria on contact lens cases and on coverslips in phosphate-buffered saline. The biofilms were then exposed to PAPB and BAK for 5 minutes and 4 hours. After exposure, alginate swabs were used to remove the biofilms from the lens cases and the bacteria were plated on tryptic soy agar for determination of survivors. Also, after exposure to these disinfectants, the A. xylosoxidans and P. aeruginosa biofilms were stained with SYTO 9 and propidium iodide. Using a confocal microscope with a 488-nm laser, the number of cells with damaged cell membranes was determined. Results. After 5 minutes of exposure to BAK or PAPB, A. xylosoxidans biofilms were more resistant to the antimicrobial effects of these disinfectants than P. aeruginosa biofilms. After 4 hours, both organisms were reduced by more than 3 logs after exposure to either BAK or PAPB. Confocal microscopy studies revealed that BAK was more effective at damaging A. xylosoxidans and P. aeruginosa cell membranes than PAPB at the concentrations used in ophthalmic products. Conclusions. Biofilms of the emerging pathogen A. xylosoxidans were more resistant to the disinfectants PAPB and BAK than biofilms of P. aeruginosa. Because of the emergence of A. xylosoxidans and the demonstrated greater resistance to the common ophthalmic preservatives BAK and PAPB than the standard Gram-negative organism P. aeruginosa, A. xylosoxidans biofilms should be assessed in antimicrobial challenge tests to assure the safety of multiuse ophthalmic products. Copyright © 2015 American Academy of Optometry.

Hall,B., Jones,L., Forrest,J. A. Kinetics of competitive adsorption between lysozyme and lactoferrin on silicone hydrogel contact lenses and the effect on lysozyme activity. Current eye research 2015;40,6:622-631. [ Show Abstract ]

To determine the effect of competitive adsorption between lysozyme and lactoferrin on silicone hydrogel contact lenses and the effect on lysozyme activity. Methods: Three commercially available silicone hydrogel contact lens materials (senofilcon A, lotrafilcon B and balafilcon A) were examined, for time points ranging from 10s to 2h. Total protein deposition was determined by I125 radiolabeling of lysozyme and lactoferrin, while the activity of lysozyme was determined by a micrococcal activity assay. Results: Senofilcon A and balafilcon A did not show any relevant competitive adsorption between lysozyme and lactoferrin. Lotrafilcon B showed reduced protein deposition due to competitive adsorption for lactoferrin at all time points and lysozyme after 7.5min. Co-adsorption of lactoferrin and lysozyme decreased the activity of lysozyme in solution for senofilcon A and lotrafilcon B, but co-adsorption had no effect on the surface activity of lysozyme for all lens types investigated. Conclusions: Competition between lysozyme and lactoferrin is material specific. Co-adsorption of lysozyme and lactoferrin does not affect the activity of surface-bound lysozyme but can reduce the activity of subsequently desorbed lysozyme. © 2015 Informa Healthcare USA, Inc.

Verma,M. S., Chen,P. Z., Jones,L., Gu,F. X. Controlling "chemical nose" biosensor characteristics by modulating gold nanoparticle shape and concentration. Sensing and Bio-Sensing Research 2015;513-18. [ Show Abstract ]

Conventional lock-and-key biosensors often only detect a single pathogen because they incorporate biomolecules with high specificity. "Chemical nose" biosensors are overcoming this limitation and identifying multiple pathogens simultaneously by obtaining a unique set of responses for each pathogen of interest, but the number of pathogens that can be distinguished is limited by the number of responses obtained. Herein, we use a gold nanoparticle-based "chemical nose" to show that changing the shapes of nanoparticles can increase the number of responses available for analysis and expand the types of bacteria that can be identified. Using four shapes of nanoparticles (nanospheres, nanostars, nanocubes, and nanorods), we demonstrate that each shape provides a unique set of responses in the presence of different bacteria, which can be exploited for enhanced specificity of the biosensor. Additionally, the concentration of nanoparticles controls the detection limit of the biosensor, where a lower concentration provides better detection limit. Thus, here we lay a foundation for designing "chemical nose" biosensors and controlling their characteristics using gold nanoparticle morphology and concentration. © 2015 The Authors.

Hagedorn,S., Drolle,E., Lorentz,H., Srinivasan,S., Leonenko,Z., Jones,L. Atomic force microscopy and Langmuir-Blodgett monolayer technique to assess contact lens deposits and human meibum extracts. Journal of Optometry 2015;8,3:187-199. [ Show Abstract ]

Purpose The purpose of this exploratory study was to investigate the differences in meibomian gland secretions, contact lens (CL) lipid extracts, and CL surface topography between participants with and without meibomian gland dysfunction (MGD). Methods Meibum study: Meibum was collected from all participants and studied via Langmuir-Blodgett (LB) deposition with subsequent Atomic Force Microscopy (AFM) visualization and surface roughness analysis. CL Study: Participants with and without MGD wore both etafilcon A and balafilcon A CLs in two different phases. CL lipid deposits were extracted and analyzed using pressure-area isotherms with the LB trough and CL surface topographies and roughness values were visualized using AFM. Results Meibum study: Non-MGD participant meibum samples showed larger, circular aggregates with lower surface roughness, whereas meibum samples from participants with MGD showed more lipid aggregates, greater size variability and higher surface roughness. CL Study: Worn CLs from participants with MGD had a few large tear film deposits with lower surface roughness, whereas non-MGD participant-worn lenses had many small lens deposits with higher surface roughness. Balafilcon A pore depths were shallower in MGD participant worn lenses when compared to non-MGD participant lenses. Isotherms of CL lipid extracts from MGD and non-MGD participants showed a seamless rise in surface pressure as area decreased; however, extracts from the two different lens materials produced different isotherms. Conclusions MGD and non-MGD participant-worn CL deposition were found to differ in type, amount, and pattern of lens deposits. Lipids from MGD participants deposited irregularly whereas lipids from non-MGD participants showed more uniformity. © 2014 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Hall,B., Jones,L. W., Forrest,J. A. Competitive effects from an artificial tear solution to protein adsorption. Optometry and Vision Science 2015;92,7:781-789. [ Show Abstract ]

Purpose To compare the adsorption of lysozyme, lactoferrin, and albumin to various contact lens materials, between single-protein solutions and a multicomponent artificial tear solution (ATS). Additionally, extra steps were taken to distinguish loosely and tightly bound protein, the latter of which may be fully or partially denatured. Methods Using a previously described ATS, we measured the time-dependent adsorption of lys, lac, and alb onto one conventional hydrogel and four silicone hydrogel contact lens materials between the first minute and up to 1 week of protein interaction with the material surface. Proteins were quantified using I125 radiolabeling of each protein individually in ATS and buffered saline. Extra steps were taken to limit the amount of unbound I125 and to quantify the amount of reversibly bound protein. Results Comfilcon A, balafilcon A, and etafilcon A did not show any relevant competitive adsorption between the ATS components and lys, lac, or alb until after 1 week. Competitive adsorption effects for lys, lac, and alb were observed in as little as 1 minute on lotrafilcon B. Lotrafilcon B had no reversibly bound protein at any time points. The ionic materials balafilcon A and etafilcon A deposited significant amounts of reversibly bound lysozyme and lactoferrin in just 10 minutes. Senofilcon A apparent deposition was below our thresholds of confidence for this protein quantification method. Conclusions Both the competition between lys, lac, and alb and ATS components and the reversibility of these bound proteins is material specific. Coadsorption of lys, lac, and alb with ATS components can increase the reversibility of their adsorption. © 2015 American Academy of Optometry.

Omali,N. B., Subbaraman,L. N., Coles-Brennan,C., Fadli,Z., Jones,L. W. Biological and clinical implications of lysozyme deposition on soft contact lenses. Optometry and Vision Science 2015;92,7:750-757. [ Show Abstract ]

Within a few minutes of wear, contact lenses become rapidly coated with a variety of tear film components, including proteins, lipids, and mucins. Tears have a rich and complex composition, allowing a wide range of interactions and competitive processes, with the first event observed at the interface between a contact lens and tear fluid being protein adsorption. Protein adsorption on hydrogel contact lenses is a complex process involving a variety of factors relating to both the protein in question and the lens material. Among tear proteins, lysozyme is a major protein that has both antibacterial and anti-inflammatory functions. Contact lens materials that have high ionicity and high water content have an increased affinity to accumulate lysozyme during wear, when compared with other soft lens materials, notably silicone hydrogel lenses. This review provides an overview of tear film proteins, with a specific focus on lysozyme, and examines various factors that influence protein deposition on contact lenses. In addition, the impact of lysozyme deposition on various ocular physiological responses and bacterial adhesion to lenses and the interaction of lysozyme with other tear proteins are reviewed. This comprehensive review suggests that deposition of lysozyme on contact lens materials may provide a number of beneficial effects during contact lens wear. © 2015 American Academy of Optometry.

Srinivasan,S., Otchere,H., Yu,M., Yang,J., Luensmann,D., Jones,L. Impact of cosmetics on the surface properties of silicone hydrogel contact lenses. Eye and Contact Lens 2015;41,4:228-235. [ Show Abstract ]

Purpose: This study evaluated the impact of various cosmetics on the surface properties of silicone hydrogel (SiHy) contact lens materials. Methods: In this in vitro experiment, 7 SiHy contact lens materials were coated with 1 of 9 cosmetics, including common hand creams (3), eye makeup removers (3), and mascaras (3). Dark-field microscopy images were taken to determine pixel brightness (PB) after cosmetic exposure, which describes the visible surface deposition (n=6 for each lens type), with a higher PB indicating increased deposition. The sessile drop technique was used to determine the advancing contact angle (CA). Measurements were repeated for both methods after a single peroxide-based cleaning cycle. Results: Pixel brightness was significantly higher for mascara-coated lenses compared with the other cosmetic products (P,0.01). The peroxide-based lens care solution removed most deposits from the nonwaterproof mascara for 4 lens types, whereas deposits remained relatively unchanged for 1 waterproof mascara (P.0.05). Hand creams and makeup remover had minimal impact on PB. Changes in CA measurements after cosmetic application were highly lens dependent. Hand creams caused primarily a decrease in CA for 5 of the 7 lens types, whereas 1 of the waterproof mascaras caused a significant increase of 30 to 50° for 3 lens types. Conclusion: Some mascara-lens combinations resulted in increased CA and PB, which could have an impact on in vivo lens performance. Nonwaterproof mascara was mostly removed after a cleaning cycle. Further research is needed to understand the clinical implications for SiHy lens wearers using cosmetics. © 2015 Contact Lens Association of Opthalmologists, Inc.

Luensmann,D., Yu,M., Yang,J., Srinivasan,S., Jones,L. Impact of cosmetics on the physical dimension and optical performance of silicone hydrogel contact lenses. Eye and Contact Lens 2015;41,4:218-227. [ Show Abstract ]

Objectives: To evaluate the impact of cosmetics on silicone hydrogel (SiHy) contact lens shape, lens power, and optical performance. Methods: In this in vitro experiment, 7 SiHy materials were coated with 9 marketed brands of cosmetics, including hand creams (HCs) (3), eye makeup removers (MRs) (3), and mascaras (3). Diameter, sagittal depth, and base curve were determined using the Chiltern (Optimec Limited), whereas lens power and optical performance were assessed using the Contest Plus (Rotlex). Six replicates were used for each lens and cosmetic combination.Measurements were repeated after a cleaning cycle using a one-step hydrogen peroxide solution. Results: Makeup removers had the greatest impact on diameter, sagittal depth, and base curve, resulting in changes of up to 0.5, 0.15, and 0.77 mm, respectively. The HCs and mascaras had little impact on these parameters; however, differences were observed between lens types. Optical performance was reduced with all mascaras, and a decrease of greater than 2 units on a 0 to 10 scale (10=uniform power distribution) was seen for 5 lens types exposed to waterproof mascara (P0.05). Lens cleaning resulted in some recovery of the lens parameters, and efficiency varied between cosmetics. Conclusion: Some eye MRs and waterproof mascaras changed the shape and optical performance of some SiHy lenses. Further research is needed to understand the clinical implications for SiHy lens wearers using cosmetics. © 2015 Contact Lens Association of Opthalmologists, Inc.

Bajgrowicz,M., Phan,C. -M, Subbaraman,L. N., Jones,L. Release of ciprofloxacin and moxifloxacin from daily disposable contact lenses from an in vitro eye model. Investigative Ophthalmology and Visual Science 2015;56,4:2234-2242. [ Show Abstract ]

Purpose. To analyze the release of two fluoroquinolones, ciprofloxacin and moxifloxacin, from conventional hydrogel (CH) and silicone hydrogel (SH) daily disposable contact lenses (CLs), comparing release from a fixed-volume vial and a novel in vitro eye model. Methods. Four CH CLs (nelfilcon A, omafilcon A, etafilcon A, ocufilcon B) and three SH CLs (somofilcon A, narafilcon A, delefilcon A) were used. The lenses were incubated in drug solutions for 24 hours. After the incubation period, the lenses were placed in two release conditions: (1) a vial containing 4.8 mL PBS for 24 hours and (2) an in vitro eye model with a flow rate at 4.8 mL over 24 hours. Results. Release in the vial for both drugs was rapid, reaching a plateau between 15 minutes and 2 hours for all lenses. In contrast, under physiological flow conditions, a constant and slow release was observed over 24 hours. The amounts of ciprofloxacin released from the lenses ranged between 49.6 ±0.7 and 62.8 ± 0.3 µg per lens in the vial, and between 35.0 ± 7.0 and 109.0 ± 5.0 µg per lens in the eye model. Moxifloxacin release ranged from 24.0 ± 4.0 to 226.0 ± 2.0 µg per lens for the vial, and between 13.0 ± 2.0 and 151.0 ± 10.0 µg per lens in the eye model. In both systems and for both drugs, HEMA-based CLs released more drugs than other materials. Conclusions. The parameters of the release system, in particular the volume and flow rate, have a significant influence on measured release profiles. Under physiological flow, release profiles are significantly slower and constant when compared with release in a vial. © 2015, The Association for Research in Vision and Ophthalmology, Inc.

Verma,M. S., Rogowski,J. L., Jones,L., Gu,F. X. Colorimetric biosensing of pathogens using gold nanoparticles. Biotechnology Advances 2015;33,6:666-680. [ Show Abstract ]

Rapid detection of pathogens is crucial to minimize adverse health impacts of nosocomial, foodborne, and waterborne diseases. Gold nanoparticles are extremely successful at detecting pathogens due to their ability to provide a simple and rapid color change when their environment is altered. Here, we review general strategies of implementing gold nanoparticles in colorimetric biosensors. First, we highlight how gold nanoparticles have improved conventional genomic analysis methods by lowering detection limits while reducing assay times. Then, we focus on emerging point-of-care technologies that aim at pathogen detection using simpler assays. These advances will facilitate the implementation of gold nanoparticle-based biosensors in diverse environments throughout the world and help prevent the spread of infectious diseases. © 2015 Elsevier Inc.

Pucker,A. D., Jones-Jordan,L. A., Li,W., Kwan,J. T., Lin,M. C., Sickenberger,W., Marx,S., Srinivasan,S., Jones,L. W. Associations with meibomian gland atrophy in daily contact lens wearers. Optometry and Vision Science 2015;92,9:e206-e213. [ Show Abstract ]

Purpose To determine associations for contact lenses (CLs) and meibomian gland atrophy in a matched-pair study. Methods Contact lens wearers (case) and age- and sex-matched non-contact lens (NCL) wearers with no history of CL use (control) were recruited for a multicenter study. All subjects were administered the Ocular Surface Disease Index questionnaire and a comprehensive battery of clinical tests (e.g., tear breakup time, bulbar and limbal redness, meibography, etc.) were performed. Upper and lower eyelid meibomian gland atrophy were graded with both digital meibography (percent gland atrophy) and visual meiboscore methods. Conditional logistic regression analyses were then used to determine relationships among CL use, meibomian gland atrophy, and ocular surface signs and symptoms. Results A total of 70 matched pairs were analyzed. The mean (±SD) age of the CL group was 30.6 (±12.4) years, and that of the NCL group was 30.1 (±12.2) years. The subjects were 63% female. The association between CL wear and meiboscore was not significant univariately, but the best-fitting multivariate regression model showed that higher meiboscores were associated with being a CL wearer (odds ratio [OR], 2.45) in a model that included eyelid margin erythema (OR, 0.25) and lissamine green staining (OR, 1.25). Percent gland atrophy was not associated with CL wear in regression analysis (p = 0.31). Conclusions This study determined inconclusive associations with CLs and meibomian gland atrophy. This study also provided a comprehensive assessment of differences between CL and NCL wearers. © 2015 American Academy of Optometry.

Ngo,W., Caffery,B., Srinivasan,S., Jones,L. W. Effect of lid debridement-scaling in sjögren syndrome dry eye. Optometry and Vision Science 2015;92,9:e316-e320. [ Show Abstract ]

Purpose To evaluate the effect of lid debridement-scaling (LDS) on dry eye signs and symptoms in subjects with Sjögren syndrome (SS). Methods This prospective randomized controlled study enrolled 14 female subjects with SS. Seven subjects were randomized into the treatment group where they were selected to receive LDS; the remainder did not receive LDS and served as control subjects. Lid debridement-scaling was conducted using a stainless steel golf club spud (Hilco Wilson Ophthalmics, Plainville, MA) on both the upper and lower eyelids of both eyes. Outcome variables were assessed before LDS and again 1 month later. The outcome variables were the Ocular Surface Disease Index (OSDI), Symptom Assessment iN Dry Eye (SANDE) visual analog scores, ocular staining (SICCA OSS [Sjögren's International Collaborative Clinical Alliance Ocular Staining Score]), fluorescein tear breakup time (FLBUT), meibomian gland score (MGS), meibomian gland yielding liquid secretions (MGYLS) score, and line of Marx's (LOM) position. Results Thirteen subjects completed the study. Data from only the right eye were analyzed. For the control group (n = 6; mean [±SD] age, 62.3 [±11.6] years), the pre-LDS, post-LDS, and significance level (pre-LDS mean [±SD] vs. post-LDS mean [±SD]; p value) were as follows: OSDI (58.3 [±22.1] vs. 48.3 [±29.0]; p = 0.051), SANDE (77.4 [±22.1] vs. 89.6 [±32.6]; p = 0.20), SICCA OSS (7.0 [±4.5] vs. 8.2 [±3.5]; p = 0.25), MGS (1.3 [±1.5] vs. 1.0 [±0.9]; p = 0.75), MGYLS (0.3 [±0.5] vs. 0.0 [±0.0]; p = 0.50), FLBUT (2.99 [±1.54] vs. 2.85 [±1.79]; p = 0.63), and LOM (2.0 [±0.0] vs. 2.0 [±0.0]; p = n/a). For the treatment group (n = 7; mean [±SD] age, 58.0 [±8.1] years), the pre-LDS, post-LDS, and significance level were as follows: OSDI (63.2 [±13.3] vs. 46.9 [±19.4]; p = 0.04), SANDE (72.6 [±17.1] vs. 77.0 [±28.0]; p = 0.54), SICCA OSS (6.6 [±2.9] vs. 5.0 [±3.9]; p = 0.02), MGS (1.0 [±1.2] vs. 3.1 [±1.7]; p = 0.01), MGYLS (0.0 [±0.0] vs. 0.6 [±1.0]; p = 0.50), FLBUT (3.13 [±0.81] vs. 3.45 [±1.03]; p = 0.53), and LOM (0.9 [±0.9] vs. 1.0 [±1.0]; p = 1.00). Conclusions This pilot study showed that LDS improved symptoms, ocular staining, and meibomian gland function for the group that received LDS. This indicates that LDS can aid in the management of SS dry eye. © 2015 American Academy of Optometry.

Guthrie,S. E., Jones,L., Blackie,C. A., Korb,D. R. A Comparative Study Between an Oil-in-Water Emulsion and Nonlipid Eye Drops Used for Rewetting Contact Lenses. Eye and Contact Lens 2015;41,6:373-377. [ Show Abstract ]

OBJECTIVES: The purpose of this study was to determine the clinical impact of using SYSTANE BALANCE Lubricant Eye Drops (Alcon, Fort Worth, TX), an oil-in-water emulsion, as a rewetting eye drop in symptomatic contact lens wearers. METHODS: Subjects who had previously experienced contact lens discomfort (CLD), with a mean lens wearing history of 18.6±12.8 years, were randomly assigned to use a Test (SYSTANE BALANCE Lubricant Eye Drops; n=76) or control (habitual nonlipid contact lens rewetting eye drop; n=30) drop over their contact lenses within 5 min of lens insertion and then subsequently at 2 hr intervals up to a maximum of 4 drops per eye daily for a 1-month period. Assessments of subjective comfort, comfortable wearing time, lid wiper epitheliopathy (LWE), and corneal staining were conducted at baseline and after 1 month, after 6 hr of lens wear. RESULTS: Comfort, wearing time, LWE, and corneal staining all showed statistically significant improvements in the test group using SYSTANE BALANCE Lubricant Eye Drops at the 1-month visit compared with baseline data (all P<0.01) and compared with the control group at the 1-month visit (P<0.01, P=0.01, P<0.01, and P=0.03, respectively). CONCLUSIONS: The use of SYSTANE BALANCE Lubricant Eye Drops as a rewetting drop in a group of wearers who experienced symptoms of CLD improved subjective comfort scores, increased comfortable wearing time, and reduced signs of LWE and corneal staining, when compared with the use of non–lipid-containing contact lens rewetting eye drops. © 2015 Contact Lens Association of Ophthalmologists, Inc.

Samsom,M., Chan,A., Iwabuchi,Y., Subbaraman,L., Jones,L., Schmidt,TA In vitro friction testing of contact lenses and human ocular tissues: Effect of proteoglycan 4 (PRG4). Tribology International 2015;8927-33. [ Show Abstract ]

Contact lens friction was recently shown to correlate with in vivo comfort, with lower friction lenses providing improved comfort. Proteoglycan 4 (PRG4) is a recently discovered ocular surface boundary lubricant. The objectives of this study were to measure the friction of commercially available silicone hydrogel (SiHy) contact lenses against human cornea and eyelid tissues, and evaluate the ability of PRG4 to lubricate, and adhere to, SiHy contact lenses. The in vitro friction test employed here effectively measured and distinguished the SiHy contact lens friction coefficients against human eyelid and cornea tissues, and PRG4 functioned as an effective boundary lubricant.

2014

Caffery,B. E., Joyce,E., Heynen,M. L., Ritter,R., Jones,L. A., Senchyna,M. Quantification of conjunctival TNF-a in aqueous-deficient dry eye. Optometry and Vision Science 2014;91,2:156-162. [ Show Abstract ]

PURPOSE: This study aimed to quantify and compare conjunctival epithelial tumor necrosis factor (NF) a mRNA expression in Sjögren syndrome (SS), non-Sjögren syndrome aqueous-deficient dry eye (non-SS DE), and non-dry eye (NDE) control subjects. METHODS: A total of 76 subjects were recruited for this study: 25 SS (confirmed via American-European Consensus Criteria 2002), 25 non-SS DE (confirmed by symptoms and Schirmer scores = 10 mm), and 26 NDE. Superior and temporal bulbar conjunctival epithelial cells were collected via impression cytology. Epithelial RNA was extracted, and TNF-a mRNA expression was quantified by real-time quantitative polymerase chain reaction. RESULTS: The expression of TNF-a mRNA was found to be significantly higher in the SS group (2.48 ± 1.79) compared to both non-SS DE (0.95 ± 1.18; p < 0.05) and NDE (0.84 ± 0.51; p < 0.05) groups. No difference in TNF-a mRNA expression was found between the non-SS DE and NDE groups (p = 0.67). CONCLUSIONS: These results demonstrate that SS-associated aqueous-deficient dry eye is associated with a significant upregulation of conjunctival epithelial TNF-a mRNA relative to both non-SS DE and control groups. The degree to which TNF-a mRNA is upregulated in SS may contribute to the severe ocular surface damage observed in these patients. Copyright © 2014 American Academy of Optometry.

Hall,B., Phan,C. -M, Subbaraman,L., Jones,L. W., Forrest,J. Extraction versus in Situ techniques for measuring surface-adsorbed lysozyme. Optometry and Vision Science 2014;91,9:1062-1070. [ Show Abstract ]

PURPOSE: To compare two techniques for measuring the activity of lysozyme deposited onto hydrogel contact lens and to image the binding of Micrococcus lysodeikticus to contact lenses. METHODS: Using a previously described protein extraction technique and a recently developed in situ technique, we measured the time-dependent activity of adsorbed lysozyme on six different contact lens materials during the first minute and up to 1 week of interaction with the material surface. Total activity of extracted lysozyme, total in situ activity, and the activity of the outer surface layer of sorbed lysozyme were determined using the two different techniques. Micrococcal cellular interaction with surface-adsorbed lysozyme was imaged using confocal microscopy. RESULTS: The differences between total extracted activities, total in situ activities, and surface activities were both measurable and material specific. In most cases, total extracted activity is greater than total in situ activity, which, in turn, is greater than surface activity. After 1 week, etafilcon A had the highest extracted activity at 137 µg/lens, followed by omafilcon A, balafilcon A, comfilcon A, senofilcon A, and lotrafilcon B at 27.4, 2.85, 2.02, 0.46, and 0.27 µg/lens, respectively. Micrococcal cell adhesion was greatest on contact lenses with high contact angles, such as balafilcon A, omafilcon A, and senofilcon A and lowest on contact lenses with low contact angles, such as etafilcon A, comfilcon A, and lotrafilcon B. Subsequent removal/prevention of adhered micrococcal cells was greatest on balafilcon A, which had the highest surface activity, and lowest on lotrafilcon B, which had the lowest surface activity. CONCLUSIONS: This study has measured and made direct comparisons between two established techniques for measuring the activity of adsorbed lysozyme. The extraction technique determines the activity of underlying layers of lysozyme or lysozyme within the matrix of the material. Conversely, the in situ technique allows conclusions to be drawn about only the biologically relevant lysozyme including the activity of just the outer surface of adsorbed lysozyme. © American Academy of Optometry.

Cheung,S., Lorentz,H., Drolle,E., Leonenko,Z., Jones,L. W. Comparative study of lens solutions' ability to remove tear constituents. Optometry and Vision Science 2014;91,9:1045-1061. [ Show Abstract ]

PURPOSE: The purpose of this study was to use atomic force microscopy to compare and characterize the cleaning abilities of a hydrogen peroxide-based system (HPS) and a polyhexamethylene biguanide-containing multipurpose solution (MPS) at removing in vitro deposited tear film constituents, as well as to determine deposition patterns on various silicone hydrogel contact lenses. METHODS: Silicone hydrogel materials - balafilcon A (BA), lotrafilcon B (LB), and senofilcon A (SA) - were incubated for 1 week in an artificial tear solution (ATS) containing representative lipids, proteins, and salts from the tear film. Atomic force microscopy was used to resolve each lens before and after being cleaned overnight in HPS or MPS. Atomic force microscopy was used again to resolve HPS/MPS-cleaned lenses, which were reincubated in fresh ATS for 1 week, before and after an overnight clean in their respective cleaning solution. RESULTS: Atomic force microscopy imaging was able to characterize lens deposits with high resolution. Lenses incubated in ATS revealed distinct differences in their deposition pattern across lens materials. The surface of BA contained about 20-nm-high deposits, whereas deposit heights up to 150 nm completely occluded the surface of SA. Lotrafilcon B lenses revealed clusters of deposits up to 90 nm. The use of either lens solution left trace amounts of tear film constituents, although components from the MPS were seen adsorbed onto the surface after cleaning. Surface roughness (Ra) measurements revealed a significant difference between ATS-incubated and HPS/MPS-cleaned SA and LB lenses (p < 0.05). Ra between first incubated and HPS/MPS-cleaned reincubated SA and LB was also significant (p < 0.05). CONCLUSIONS: Unique variations in ATS deposition patterns were seen between lenses with atomic force microscopy. The application of both HPS and MPS removed most visible surface deposits. © American Academy of Optometry.

Mohammadi,S., Jones,L., Gorbet,M. Extended latanoprost release from commercial contact lenses: In vitro studies using corneal models. PLOS ONE 2014;9,9:e106653. [ Show Abstract ]

In this study, we compared, for the first time, the release of a 432 kDa prostaglandin analogue drug, Latanoprost, from commercially available contact lenses using in vitro models with corneal epithelial cells. Conventional polyHEMA-based and silicone hydrogel soft contact lenses were soaked in drug solution ( solution in phosphate buffered saline). The drug release from the contact lens material and its diffusion through three in vitro models was studied. The three in vitro models consisted of a polyethylene terephthalate (PET) membrane without corneal epithelial cells, a PET membrane with a monolayer of human corneal epithelial cells (HCEC), and a PET membrane with stratified HCEC. In the cell-based in vitro corneal epithelium models, a zero order release was obtained with the silicone hydrogel materials (linear for the duration of the experiment) whereby, after 48 hours, between 4 to 6  of latanoprost (an amount well within the range of the prescribed daily dose for glaucoma patients) was released. In the absence of cells, a significantly lower amount of drug, between 0.3 to 0.5 , was released, (). The difference observed in release from the hydrogel lens materials in the presence and absence of cells emphasizes the importance of using an in vitrocorneal model that is more representative of the physiological conditions in the eye to more adequately characterize ophthalmic drug delivery materials. Our results demonstrate how in vitro models with corneal epithelial cells may allow better prediction of in vivo release. It also highlights the potential of drug-soaked silicone hydrogel contact lens materials for drug delivery purposes.

Verma,M. S., Chen,P. Z., Jones,L., Gu,F. X. "Chemical nose" for the visual identification of emerging ocular pathogens using gold nanostars. Biosensors and Bioelectronics 2014;61386-390. [ Show Abstract ]

Ocular pathogens can cause serious damages in the eye leading to severe vision loss and even blindness if left untreated. Identification of pathogens is crucial for administering the appropriate antibiotics in order to gain effective control over ocular infection. Herein, we report a gold nanostar based "chemical nose" for visually identifying ocular pathogens. Using a spectrophotometer and nanostars of different sizes and degrees of branching, we show that the "chemical nose" is capable of identifying the following clinically relevant ocular pathogens with an accuracy of 99%: S. aureus, A. xylosoxidans, D. acidovorans and S. maltophilia. The differential colorimetric response is due to electrostatic aggregation of cationic gold nanostars around bacteria without the use of biomolecule ligands such as aptamers or antibodies. Transmission electron microscopy confirms that the number of gold nanostars aggregated around each bacterium correlates closely with the colorimetric response. Thus, gold nanostars serve as a promising platform for rapid visual identification of ocular pathogens with application in point-of-care diagnostics. © 2014 Elsevier B.V.

Phan,C. -M, Subbaraman,L. N., Jones,L. In vitro drug release of natamycin from ß-cyclodextrin and 2-hydroxypropyl-ß-cyclodextrin-functionalized contact lens materials. Journal of Biomaterials Science, Polymer Edition 2014;25,17:1907-1919. [ Show Abstract ]

Purpose: The antifungal agent natamycin can effectively form inclusion complexes with beta-cyclodextrin (ß-CD) and 2-hydroxypropyl-ß-cyclodextrin (HP-ßCD) to improve the water solubility of natamycin by 16-fold and 152-fold, respectively (Koontz, J. Agric. Food. Chem. 2003). The purpose of this study was to develop contact lens materials functionalized with methacrylated ß-CD (MßCD) and methacrylated HP-ßCD (MHP-ßCD), and to evaluate their ability to deliver natamycin in vitro. Methods: Model conventional hydrogel (CH) materials were synthesized by adding varying amounts of MßCD and MHP-ßCD (0, 0.22, 0.44, 0.65, 0.87, 1.08% of total monomer weight) to a monomer solution containing 2-hydroxyethyl methacrylate (HEMA). Model silicone hydrogel (SH) materials were synthesized by adding similar concentrations of MßCD and MHP-ßCD to N,N-dimethylacrylamide (DMAA)/10% 3-methacryloxypropyltris(trimethylsiloxy)silane (TRIS). The gels were cured with UV light, washed with ethanol and then, hydrated for 24 h (h). The model materials were then incubated with 2 mL of 100 g/mL of natamycin in phosphate buffered saline (PBS) pH 7.4 for 48 h at room temperature. The release of natamycin from these materials in 2 mL of PBS, pH 7.4 at 32 ± 2 °C was monitored using UV-vis spectrophotometry at 304 nm over 24 h. Results: For both CH and SH materials, functionalization with MßCD and MHP-ßCD improved the total amount of drugs released up to a threshold loading concentration, after which further addition of methacrylated CDs decreased the amount of drugs released (p < 0.05). The addition of CDs did not extend the drug release duration; the release of natamycin by all model materials reached a plateau after 12 h (p < 0.05). Overall, DMAA/10% TRIS materials released significantly more drug than HEMA materials (p < 0.05). The addition of MHP-ßCD had a higher improvement in drug release than MßCD for both HEMA and DMAA/10% TRIS gels (p < 0.05). Conclusions: A high loading concentration of methacrylated CDs decreases overall drug delivery efficiency, which likely results from an unfavorable arrangement of the CDs within the polymer network leading to reduced binding of natamycin to the CDs. HEMA and DMAA/10% TRIS materials functionalized with MHP-ßCD are more effective than those functionalized with MßCD to deliver natamycin.

Samsom,M., Chan,A., Iwabuchi,Y., Subbaraman,L., Jones,L., Schmidt,TA In vitro friction testing of contact lenses and human ocular tissues: Effect of proteoglycan 4 (PRG4). Tribology International 2014.

Gorbet,M., Peterson,R., McCanna,D., Woods,C., Jones,L., Fonn,D. Human corneal epithelial cell shedding and fluorescein staining in response to silicone hydrogel lenses and contact lens disinfecting solutions. Current eye research 2014;39,3:245-256. [ Show Abstract ]

Purpose: A pilot study was conducted to evaluate human corneal epithelial cell shedding in response to wearing a silicone hydrogel contact lens/solution combination inducing corneal staining. The nature of ex vivo collected cells staining with fluorescein was also examined. Methods: A contralateral eye study was conducted in which up to eight participants were unilaterally exposed to a multipurpose contact lens solution/silicone hydrogel lens combination previously shown to induce corneal staining (renu® fresh™ and balafilcon A; test eye), with the other eye using a combination of balafilcon A soaked in a hydrogen peroxide care system (Clear Care®; control eye). Lenses were worn for 2, 4 or 6 hours. Corneal staining was graded after lens removal. The Ocular Surface Cell Collection Apparatus was used to collect cells from the cornea and the contact lens. Results: In the test eye, maximum solution-induced corneal staining (SICS) was observed after 2 hours of lens wear (reducing significantly by 4 hours; p < 0.001). There were significantly more cells collected from the test eye after 4 hours of lens wear when compared to the control eye and the collection from the test eye after 2 hours (for both; n = 5; p < 0.001). The total cell yield at 4 hours was 813 ± 333 and 455 ± 218 for the test and control eyes, respectively (N = 5, triplicate, p = 0.003). A number of cells were observed to have taken up the fluorescein dye from the initial fluorescein instillation. Confocal microscopy of fluorescein-stained cells revealed that fluorescein was present throughout the cell cytoplasm and was retained in the cells for many hours after recovery from the corneal surface. Conclusion: This pilot study indicates that increased epithelial cell shedding was associated with a lens-solution combination which induces SICS. Our data provides insight into the transient nature of the SICS reaction and the nature of fluorescein staining observed in SICS. © 2014 Informa Healthcare USA, Inc.

Hall,B., McCanna,D., Jones,L. Identification of coagulase-negative staphylococci in daily disposable contact lens wearers. Letters in applied microbiology 2014;59,3:313-319. [ Show Abstract ]

This study aimed to identify and quantify the number of contaminating organisms on daily disposable (DD) soft contact lenses, which may be responsible for mild cases of keratitis that occur with this lens wear modality. Ten participants wore DD lenses, and 10 participants wore planned replacement (PR) lenses. Lenses were collected aseptically and analysed for microbial contamination. Colony-forming units (CFU) were recorded, and representative colonies were used for identification using the API identification system. The DD lenses evaluated in this study were contaminated with coagulase-negative staphylococcus (CNS), ranging from 1 to 653 CFU. PR lenses showed more diversity in the types of contaminating micro-organisms and consisted of CNS, Gram-negative bacteria (Pseudomonas), a yeast (Candida) and a mould (Aspergillus), ranging from 1 to 230 CFU. CNS was the only type of micro-organism found on DD contact lenses and therefore may be the cause of any form of keratitis observed in DD lens wearers. © 2014 The Society for Applied Microbiology.

Hall,B. J., Jones,L. W., Dixon,B. Silicone allergies and the eye: Fact or fiction?. Eye and Contact Lens 2014;40,1:51-57. [ Show Abstract ]

OBJECTIVE: The purpose of this manuscript was to review the evidence concerning the role of an allergic reaction to silicone as the basis for the reported increase in contact lens-associated infiltrates in wearers of silicone hydrogel contact lenses. METHODS: A literature review was undertaken to investigate the antigenic properties of silicone and the causes of contact lens-associated inflammatory reactions. RESULTS: Immune cells cannot interact with silicone directly but can interact with antigens on these lenses. These antigens could be due to tear film deposits, microbial contamination, or components of care systems used with these lenses. CONCLUSIONS: Inflammatory reactions associated with silicone hydrogel contact lens wear are not caused by an allergic reaction to silicone alone. © 2013 Contact Lens Association of Ophthalmologists.

Hui,A., Willcox,M., Jones,L. In vitro and in vivo evaluation of novel ciprofloxacin-releasing silicone hydrogel contact lenses. Investigative Ophthalmology and Visual Science 2014;55,8:4896-4904. [ Show Abstract ]

PURPOSE. The purpose of this study was to evaluate ciprofloxacin-releasing silicone hydrogel contact lens materials in vitro and in vivo for the treatment of microbial keratitis. METHODS. Model silicone hydrogel contact lens materials were manufactured using a molecular imprinting technique to modify ciprofloxacin release kinetics. Various contact lens properties, including light transmission and surface wettability, were determined, and the in vitro ciprofloxacin release kinetics elucidated using fluorescence spectrophotometry. The materials then were evaluated for their ability to inhibit Pseudomonas aeruginosa growth in vitro and in an in vivo rabbit model of microbial keratitis. RESULTS. Synthesized lenses had similar material properties to commercial contact lens materials. There was a decrease in light transmission in the shorter wavelengths due to incorporation of the antibiotic, but over 80% light transmission between 400 and 700 nm. Modified materials released for more than 8 hours, significantly longer than unmodified controls (P 0.05), which is significantly less than corneas treated with unmodified control lenses or those that received no treatment at all (P < 0.05). CONCLUSIONS. These novel contact lenses designed for the extended release of ciprofloxacin may be beneficial to supplement or augment future treatments of sight-threatening microbial keratitis. © 2014 The Association for Research in Vision and Ophthalmology, Inc.

Ngo,W., Srinivasan,S., Schulze,M., Jones,L. Repeatability of grading meibomian gland dropout using two infrared systems. Optometry and Vision Science 2014;91,6:658-667. [ Show Abstract ]

PURPOSE: To determine the interobserver and intraobserver repeatability in using the OCULUS Keratograph 4 (K4) and 5M (K5M) to grade meibomian gland (MG) dropout using meibography grading scales. METHODS: The inferior and superior eyelids of 40 participants (35 women, 5 men; mean age = 32 years) were imaged three times each on both instruments. The images were split into one training and two study sets; the latter were graded (four-point meibography scale) by two observers on two separate occasions (24 hours apart) to determine repeatability. Semiobjective quantification of percentage MG dropout was conducted using ImageJ on K4 and K5M images. A finer seven-point meibography scale was used to grade a separate set of K5M images. RESULTS: For the four-point scale, interobserver mean difference (MD) (±SD) was 0.08 (±0.55) on day 1 and 0.13 (±0.50) on day 2, and the concordance correlation coefficient (CCC) was 0.79 and 0.81 on days 1 and 2, respectively. Intraobserver MD (±SD) was 0.04 (±0.54), CCC = 0.79 for observer 1; intraobserver MD (±SD) was -0.09 (±0.60), CCC = 0.74 for observer 2. For the seven-point scale, interobserver MD (±SD) was 0.05 (±0.45), CCC = 0.89 on day 1, and interobserver MD (±SD) was 0.01 (±0.41), CCC = 0.91 on day 2. Intraobserver MD (±SD) was -0.10 (±0.35), CCC = 0.93 for observer 1, and intraobserver MD (±SD) was -0.06 (±0.30), CCC = 0.95 for observer 2. Percentage dropout measured between the K4 and K5M images showed lack of agreement, with 21.8% coefficient of repeatability. There was no significant correlation (r 0.05) between meibography score and clinical signs (corneal staining, gland expressibility, telangiectasia, vascularity, lash loss); however, there was a high correlation (r = 0.77; p < 0.05) between meibography score with percentage dropout. CONCLUSIONS: Observers graded from -1 to +1 grade units between and within themselves for a four-point scale, 95% of the time. Although the interobserver and intraobserver repeatability of the K4 and K5M were very similar, a high rate of disagreement in percentage dropout between K4 and K5M images suggests that the two instruments cannot be interchanged. Meibomian gland dropout scores did not correlate significantly with clinical signs. Using a finer scale may be beneficial for detecting change.

Phan,CM, Hui,A., Subbaraman,L., Jones,L. Insights to Using Contact Lenses for Drug Delivery. Clin Exp Pharmacol 2014;3,145:2161-1459. [ Show Abstract ]

There has been considerable interest in the potential application of contact lenses for ocular drug delivery. This short communication provides an overview of the challenges faced by delivering drugs using contact lenses, highlights the solutions to limitations that have already been achieved, and describes the barriers that remain before commercial application can be realized.

Phan,C. -M, Subbaraman,L., Jones,L. Contact lenses for antifungal ocular drug delivery: A review. Expert Opinion on Drug Delivery 2014;11,4:537-546. [ Show Abstract ]

Introduction: Fungal keratitis, a potentially blinding disease, has been difficult to treat due to the limited number of approved antifungal drugs and the taxing dosing regimen. Thus, the development of a contact lens (CL) as an antifungal drug delivery platform has the potential to improve the treatment of fungal keratitis. A CL can serve as a drug reservoir to continuously release drugs to the cornea, while limiting drug loss through tears, blinking, drainage and non-specific absorption. Areas covered: This review will provide a summary of currently available methods for delivering antifungal drugs from commercial and model CLs, including vitamin E coating, impregnated drug films, cyclodextrin-functionalized hydrogels, polyelectrolyte hydrogels and molecular imprinting. This review will also highlight some of the main factors that influence antifungal drug delivery with CLs. Expert opinion: Several novel CL materials have been developed, capable of extended drug release profiles with a wide range of antifungal drugs lasting from 8 h to as long as 21 days. However, there are factors, such as first-order release kinetics, effectiveness of continuous drug release, microbial resistance, ocular toxicity and potential complications from inserting a CL in an infected eye, that still need to be addressed before commercial applications can be realized. © Informa UK, Ltd.

Phan,C. -M, Subbaraman,L., Liu,S., Gu,F., Jones,L. In vitro uptake and release of natamycin Dex -b- PLA nanoparticles from model contact lens materials. Journal of Biomaterials Science, Polymer Edition 2014;25,1:18-31. [ Show Abstract ]

Purpose: To evaluate the uptake and release of the antifungal agent natamycin encapsulated within poly(D,L-lactide)-dextran nanoparticles (Dex-b-PLA NPs) from model contact lens (CL) materials. Methods: Six model CL materials (gel 1:poly(hydroxyethyl methacrylate, pHEMA); gel 2:85% pHEMA: 15% [Tris(trimethylsiloxy)silyl]-propyl methacrylate (TRIS); gel 3: 75% pHEMA: 25% TRIS; gel 4: 85% N,N dimethylacrylamide (DMAA): 15% TRIS; gel 5:75% DMAA: 25% TRIS; and gel 6: DMAA) were prepared using a photoinitiation procedure. The gels were incubated in: (1) natamycin dissolved in deionized (DI) water and (2) natamycin encapsulated within Dex-b-PLA NPs in dimethylsulfoxide/DI water. Natamycin release from these materials was monitored using UV-visible spectrophotometry at 304 nm over 7 d. Results: Natamycin uptake by all model CL materials increased between 1 and 7 d (p < 0.001). The uptake of natamycin-NPs was higher than the uptake of the drug alone in DI water (p < 0.05). Drug release was higher in materials containing DMAA than pHEMA (p < 0.05). All gels loaded with natamycin-NPs also released more drug compared to gels soaked with natamycin in DI water (p < 0.001). After 1 h, CL materials loaded with natamycin alone released 28-82% of the total drug release. With the exception of gel 6, this burst released was reduced to 21-54% for CL materials loaded with natamycin-NPs. Conclusions: Model CL materials loaded with natamycin-Dex-b-PLA NPs were able to release natamycin for up to 12 h under infinite sink conditions. DMAA-TRIS materials may be more suitable for drug delivery of natamycin due to the higher drug release observed with these materials. © 2013 Taylor & Francis.

Verma,M. S., Chen,P. Z., Jones,L., Gu,F. X. Branching and size of CTAB-coated gold nanostars control the colorimetric detection of bacteria. RSC Advances 2014;4,21:10660-10668. [ Show Abstract ]

Rapid detection of pathogenic bacteria is challenging because conventional methods require long incubation times. Nanoparticles have the potential to detect pathogens before they can cause an infection. Gold nanostars have recently been used for colorimetric biosensors but they typically require surface modification with antibodies or aptamers for cellular detection. Here, CTAB-coated gold nanostars have been used to rapidly (<5 min) detect infective doses of a model Gram-positive pathogen Staphylococcus aureus by an instrument-free colorimetric method. Varying the amounts of gold nanoseed precursor and surfactant can tune the size and degree of branching of gold nanostars as studied here by transmission electron microscopy. The size and morphology of gold nanostars determine the degree and rate of color change in the presence of S. aureus. The optimal formulation achieved maximum color contrast in the presence of S. aureus and produced a selective response in comparison to polystyrene microparticles and liposomes. These gold nanostars were characterized using UV-Visible spectroscopy to monitor changes in their surface plasmon resonance peaks. The visual color change was also quantified over time by measuring the RGB components of the pixels in the digital images of gold nanostar solutions. CTAB-coated gold nanostars serve as a promising material for simple and rapid detection of pathogens. © 2014 The Royal Society of Chemistry.

2013

Weeks,A., Boone,A., Luensmann,D., Jones,L., Sheardown,H. The effects of hyaluronic acid incorporated as a wetting agent on lysozyme denaturation in model contact lens materials. Journal of Biomaterials Applications 2013;28,3:323-333. [ Show Abstract ]

Conventional and silicone hydrogels as models for contact lenses were prepared to determine the effect of the presence of hyaluronic acid on lysozyme sorption and denaturation. Hyaluronic acid was loaded into poly(2-hydroxyethyl methacrylate) and poly(2-hydroxyethyl methacrylate)/TRIS - methacryloxypropyltris (trimethylsiloxy silane) hydrogels, which served as models for conventional and silicone hydrogel contact lens materials. The hyaluronic acid was cross-linked using 1-ethyl-3-(3-dimethylaminopropyl)- carbodiimide in the presence of dendrimers. Active lysozyme was quantified using a Micrococcus lysodeikticus assay while total lysozyme was determined using 125-I radiolabeled protein. To examine the location of hyaluronic acid in the gels, 6-aminofluorescein labeled hyaluronic acid was incorporated into the gels using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide chemistry and the gels were examined using confocal laser scanning microscopy. Hyaluronic acid incorporation significantly reduced lysozyme sorption in poly(2-hydroxyethyl methacrylate) (p < 0.00001) and poly(2-hydroxyethyl methacrylate)/TRIS - methacryloxypropyltris (trimethylsiloxy silane) (p < 0.001) hydrogels, with the modified materials sorbing only 20% and 16% that of the control, respectively. More importantly, hyaluronic acid also decreased lysozyme denaturation in poly(2-hydroxyethyl methacrylate) (p < 0.005) and poly(2-hydroxyethyl methacrylate)/TRIS - methacryloxypropyltris (trimethylsiloxy silane) (p < 0.02) hydrogels. The confocal laser scanning microscopy results showed that the hyaluronic acid distribution was dependent on both the material type and the molecular weight of hyaluronic acid. This study demonstrates that hyaluronic acid incorporated as a wetting agent has the potential to reduce lysozyme sorption and denaturation in contact lens applications. The distribution of hyaluronic acid within hydrogels appears to affect denaturation, with more surface mobile, lower molecular weight hyaluronic acid being more effective in preventing denaturation. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Weeks,A., Subbaraman,L. N., Jones,L., Sheardown,H. Physical entrapment of hyaluronic acid during synthesis results in extended release from model hydrogel and silicone hydrogel contact lens materials. Eye and Contact Lens 2013;39,2:179-185. [ Show Abstract ]

OBJECTIVES:: This study was designed to assess the duration of hyaluronic acid (HA) release from model contact lens materials when HA was physically incorporated into the hydrogel during synthesis and to assess the effects of the HA release on lysozyme sorption. METHODS:: Model conventional and silicone hydrogel contact lens materials containing HA of various molecular weights as a releasable wetting agent were prepared. The HA was released into phosphate-buffered saline and MilliQ water, and the release was monitored using ultraviolet spectroscopy. Hyaluronic acid release was quantified by enzyme-linked immunosorbent assay. The effect of the releasable HA on lysozyme sorption to the materials was also analyzed using 125-I-labeled protein. RESULTS:: Hyaluronic acid loaded into the materials using this method could be released from conventional hydrogel materials for 21 days; the model silicone hydrogels showed release of more than 7 weeks. With one exception, the releasable HA decreased lysozyme sorption. CONCLUSIONS:: Hyaluronic acid physically incorporated into contact lens materials during synthesis may therefore be released for extended periods of time of up to 7 weeks. Hyaluronic acid release leads to decreased protein adsorption in general. This method has potential for modification of conventional and silicone hydrogel lenses with releasable HA as a wetting agent. © 2013 Lippincott Williams & Wilkins.

Woods,J., Guthrie,S. E., Keir,N., Dillehay,S., Tyson,M., Griffin,R., Choh,V., Fonn,D., Jones,L., Irving,E. Inhibition of defocus-induced myopia in chickens. Investigative Ophthalmology and Visual Science 2013;54,4:2662-2668. [ Show Abstract ]

PURPOSE. To determine the effect of wearing a lens with a unique peripheral optical design on the development and progression of defocus-induced myopia in newly hatched chickens.METHODS. Eighty-five newly hatched chickens underwent bilateral retinoscopy and A-scan ultrasound to determine their refractive error and axial length. They were randomly divided into Control and two Test groups, in which each chicken was fitted with a goggle-lens over the right eye, with the left eye remaining untreated. The Control group wore a lens of power - 10.00 diopters (D) of standard spherical optical design. The two Test lenses both had a central optical power -10.00 D, but used different peripheral myopia progression control (MPC) designs. For all groups, retinoscopy was repeated on days 3, 7, 10, and 14; ultrasound was repeated on day 14.RESULTS. On day 0 there was no statistical difference in refractive error (mean +6.92 D) or axial length (mean 8.06 mm) between Test and Control groups or treated and untreated eyes (all P > 0.05). At day 14, 37 (43.5%) of 85 chickens had not experienced goggle detachment and were included in the final analyses. In this cohort there was a significant refractive difference between the treated eyes of the Control group (n = 17) and those of Test 1 (n = 14) and Test 2 (n = 6) groups (both P < 0.01): Control -4.65 ± 2.11 D, Test 1 +4.57 ± 3.11 D, Test 2 +1.08 ± 1.24 D (mean ± SEM). There was also a significant axial length difference (both P < 0.01): Control 10.55 ± 0.36 mm, Test 1 9.99 ± 0.14 mm, Test 2 10.17 ± 0.18 mm.CONCLUSIONS. Use of these unique MPC lens designs over 14 days caused a significant reduction in the development of defocus-induced myopia in chickens; the degree of reduction appeared to be design specific. © 2013 The Association for Research in Vision and Ophthalmology, Inc.

Duench,S., Sorbara,L., Keir,N., Simpson,T., Jones,L. Impact of silicone hydrogel lenses and solutions on corneal epithelial permeability. Optometry and Vision Science 2013;90,6:546-556. [ Show Abstract ]

PURPOSE: The primary purpose of this pilot study was to compare epithelial barrier function (EBF) and staining in a small group of participants using a silicone hydrogel (SH) lens worn on a daily basis with two different care regimens. Secondarily, the aim was to see if there was any correlation between corneal staining and EBF. METHODS: The corneal EBF of 10 non-lens wearers (control) and 15 age-matched asymptomatic SH contact lens wearers (test) were assessed using fluorophotometry. Biomicroscopy was performed to assess corneal staining after the EBF was measured. The lens wearers wore PureVision (FDA group V) SH lenses for two consecutive 1-month periods while using either Alcon Opti-Free Express or Renu Fresh using a randomized, investigator-masked, crossover design. Control subjects were assessed on one occasion, and lens wearers were examined before fitting with lenses and after 7, 14, and 28 days of lens wear, with each combination. RESULTS: Compared with the control group, both study groups had an increase in epithelial permeability at baseline (p = 0.04). There were no changes in EBF during the treatment period for either solution (p = 0.87). A significant difference in EBF was found between the test groups during the treatment period (p = 0.02), with greater permeability in the Renu Fresh-disinfected lenses. There was poor correlation between corneal staining and EBF (r = 0.35, p > 0.05) because of large individual variations. CONCLUSIONS: Daily wear of highly oxygen-permeable SH lenses increases corneal epithelial permeability to fluorescein probably because of increased mechanical effects. In addition, certain lens-solution interactions can add to this effect, as seen in this study. Despite having a low amount of central corneal staining in the Renu Fresh group, staining and EBF did not prove to be well correlated. The presence of central corneal staining is a confounding factor when measuring EBF. Copyright © 2013 American Academy of Optometry.

Dumbleton,K., Richter,D., Bergenske,P., Jones,L. W. Compliance with lens replacement and the interval between eye examinations. Optometry and Vision Science 2013;90,4:351-358. [ Show Abstract ]

PURPOSE: Eye care practitioners (ECPs) acknowledge that their patients do not always follow recommendations for lens replacement, but many may not realize the possible implications for their offices. The study was conducted to investigate whether there is a relationship between contact lens compliance and the interval between full eye examinations (IEE). METHODS: The study was conducted in ECP offices in the United States. Eye care practitioners and patients independently completed linked questionnaires, evaluating their contact lens wear and care. Patients were required to be current wearers of daily disposable (DD) lenses or reusable silicone hydrogel lenses with a manufacturer-recommended replacement frequency (MRRF) of 2 weeks (2WR) or 1 month (1MR). RESULTS: A total of 2147 questionnaires from 141 offices were eligible. Fifty-four percent of patients were wearing 2WR, 37% 1MR, and 9% DD lenses. Wearers of 2WR lenses were significantly less compliant with replacement than wearers of both DD and 1MR lenses (34% vs. 74% and 67%, both p < 0.001); patients purchasing an annual supply were more compliant (55% vs. 45%, p < 0.001). The mean IEE was 16 months and was longer for wearers who were noncompliant with the MRRF (17.4 months vs. 14.5 months, p < 0.001). Other factors affecting IEE were household income (p = 0.030), insurance (p < 0.001), purchase source (p < 0.001), and sex (p = 0.007). CONCLUSIONS: Patients who were not compliant with the MRRF had longer IEEs and were less likely to purchase an annual supply of lenses. Patients who purchased lenses from their ECP, had a higher household income, had eye examination insurance, and were female had shorter IEEs. Patients failing to replace their lenses when scheduled were also found to be less compliant with lens care procedures. Eye care practitioners should reinforce the importance of all aspects of lens wear and care with their patients, with the overall aim of reducing possible complications and retaining successful contact lens wearers in their offices. Copyright © 2013 American Academy of Optometry.

Dumbleton,K., Woods,C. A., Jones,L. W., Fonn,D. The impact of contemporary contact lenses on contact lens discontinuation. Eye and Contact Lens 2013;39,1:93-99. [ Show Abstract ]

OBJECTIVES: Discontinuation or "dropout" from contact lens (CL) wear continues to afflict the CL industry. This study was conducted to determine whether the advent of new CL materials and designs has impacted the dropout rate and the reasons for discontinuation. METHODS: Current and lapsed CL wearers residing in Canada were recruited using Facebook to take part in an on line survey investigating CL wearing experiences during 2008 to 2010 and to establish the percentage of participants who temporarily and permanently discontinued CL wear during the period surveyed. RESULTS: Four thousand two hundred seven eligible surveys were received (64% female; median age 27 years). Forty percent had lapsed from lens wear for at least 4 months; however, 62% of the lapsed wearers (LWs) resumed wear. There were no differences between LWs and nonlapsed wearers (NLWs) with respect to gender; however, LWs were older, started lens wear when older, and had not worn lenses for as long as NLWs (all P<0.001). More NLWs than LWs wore silicone hydrogel CLs (49% vs. 38%, P<0.001) and more LWs than NLWs wore daily disposable lenses and hydrogel CLs (24% vs. 19% and 22% vs. 18%, respectively, P=0.001). Primary reasons for discontinuation were discomfort (24%), dryness (20%), red eyes (7%), and expense (7%). Compliance with lens replacement was no different between LWs and NLWs (48% vs. 45%). CONCLUSIONS: About 23% of those surveyed had discontinued CL wear permanently. The primary reasons for dropping out continue to be discomfort and dryness. Dropout rates were lower in silicone hydrogel wearers. © 2013 Lippincott Williams & Wilkins.

Dumbleton,K. A., Richter,D., Woods,C. A., Aakre,B. M., Plowright,A., Morgan,P. B., Jones,L. W. A multi-country assessment of compliance with daily disposable contact lens wear. Contact Lens and Anterior Eye 2013;36,6:304-312. [ Show Abstract ]

Purpose: To investigate compliance with daily disposable contact lens (DDCL) wear and investigate re-use of lenses according to country and DDCL material worn. Methods: Optometrists invited eligible DDCL patients from their practices to participate in a survey on DDCL wear in Australia, Norway, the United Kingdom (UK) and the United States (US). Eligible participants completed an online or paper version of the survey. Results: 805 participants completed the survey (96% online): Australia 13%, Norway 32%, UK 17%, US 38%. The median age was 38 years; 66% were female. Silicone hydrogel (SiHy) DDCLs were worn by 14%. Overall, 9% were non-compliant with DDCL replacement; Australia 18%, US 12%, UK 7% and Norway 4%. There were no differences with respect to sex, years of contact lens wear experience or DDCL material (SiHy versus hydrogels). The primary reason for re-use was "to save money" (60%). Re-use of DDCLs resulted in inferior comfort at insertion and prior to lens removal (p= 0.001). 75% reported occasional napping and 28% reported sleeping overnight for at least one night in the preceding month, while wearing their DDCLs. Conclusion: Non-compliance with replacement of DDCLs occurred in all countries investigated; the rate was highest in Australia and lowest in Norway. Re-use of DDCLs was associated with reduced comfort. DDCL wearers often reported wearing lenses overnight. It is important for optometrists to counsel their patients on the importance of appropriate lens wear and replacement for DDCLs. © 2013 British Contact Lens Association.

Dumbleton,K. A., Spafford,M. M., Sivak,A., Jones,L. W. Exploring compliance: A mixed-methods study of contact lens wearer perspectives. Optometry and Vision Science 2013;90,8:898-908. [ Show Abstract ]

PURPOSE: Using both quantitative and qualitative research methods, this article explores in detail the lens wear and care habits of adapted contact lens wearers and seeks a better understanding of what enables and constrains patient compliance with appropriate lens wear and lens care. METHODS: The study was conducted in two phases: a preliminary online questionnaire (quantitative phase), identifying types of noncompliance, and a series of sequentially conducted focus groups (qualitative phase), exploring constraints to, and enablers of, compliance. RESULTS: One hundred participants completed the online questionnaire; 12 of them also participated in one of four focus groups. The most frequently reported aspects of noncompliance revealed were failure to replace lenses when scheduled, inappropriate lens purchase and supply, sleeping while wearing lenses, use of tap water with lenses and failure to wash hands, failure to clean and replace cases regularly, and inappropriate use of care systems. Using an iterative process, a number of "themes" associated with noncompliance were identified in the focus group discussions. The most frequently occurring themes related to the consequences that may occur if patients were noncompliant with one or more aspects of their contact lens wear and the importance of receiving instructions regarding the most appropriate way to wear and care for their lenses. Most of the themes that emerged during the analysis were both constraints to, and enablers of, compliance. CONCLUSIONS: This study confirms the frequent types of noncompliance with contact lens wear and care while offering a greater understanding of what may constrain and enables contact lens wear and care compliance. Future qualitative studies may help eye care practitioners and the contact lens industry to develop strategies and tools to aid compliance and success in contact lens wear. © 2013 American Academy of Optometry.

Efron,N., Brennan,N. A., Bright,F. V., Glasgow,B. J., Jones,L. W., Sullivan,D. A., Tomlinson,A., Zhang,J. Contact lens care and ocular surface homeostasis. Contact Lens and Anterior Eye 2013;36,SUPPL.:S9-S13. [ Show Abstract ]

The early focus of contact lens wear and ocular health was on oxygen delivery. However, as we learn more about how the eye works, and investigate how the contact lens interacts with the cornea, the role of the tear film has risen in prominence. A healthy tear film is critical for normal ocular homeostasis, and abnormalities of the tear film are the primary cause of dry eye. In order to improve patient eye health and comfort during lens wear, we need to further elucidate the relationship among contact lenses, contact lens solutions, the tear film, and the corneal epithelium, and find ways to maintain homeostasis of the ocular surface. In this section, we review the latest data and opinions on this complex relationship between contact lenses and lens care solutions. © 2013 British Contact Lens Association.

Efron,N., Jones,L., Bron,A. J., Knop,E., Arita,R., Barabino,S., McDermott,A. M., Villani,E., Willcox,M. D. P., Markoulli,M. The TFOS International Workshop on Contact Lens Discomfort: Report of the contact lens interactions with the ocular surface and adnexa subcommittee. Investigative Ophthalmology and Visual Science 2013;54,11:TFOS98-TFOS122.

Hall,B., Jones,L., Forrest,J. A. Measuring the kinetics and activity of adsorbed proteins: In vitro lysozyme deposited onto hydrogel contact lenses over short time periods. Journal of Biomedical Materials Research - Part A 2013;101 A,3:755-764. [ Show Abstract ]

A new process has been developed to determine the biological activity of an intact layer of lysozyme deposited onto a biomaterial surface. This process is applied to a number of common hydrogel contact lenses. The activity of the surface-adsorbed protein is measured using a standard micrococcal activity assay, with extra steps to distinguish between protein on the surface and protein in solution. This is in contrast to protein extraction work in which the activity of all adsorbed protein is measured. For ionic materials, which are known to deposit large amounts of protein, particularly positively charged proteins such as lysozyme, there is evidence for loosely bound protein re-entering the solution, thus making it impossible to truly separate out the surface-adsorbed protein. This optimized process provides the first quantification of the biological activity of an intact layer of surface-adsorbed protein at a hydrogel interface. © 2012 Wiley Periodicals, Inc.

Jones,L., Brennan,N. A., González-Méijome,J., Lally,J., Maldonado-Codina,C., Schmidt,T. A., Subbaraman,L., Young,G., Nichols,J. J. The TFOS International Workshop on Contact Lens Discomfort: Report of the contact lens materials, design, and care subcommittee. Investigative Ophthalmology and Visual Science 2013;54,11:TFOS37-TFOS70.

Jones,L., Powell,C. H. Uptake and release phenomena in contact lens care by silicone hydrogel lenses. Eye and Contact Lens 2013;39,1:29-36. [ Show Abstract ]

Contact lens solutions are highly complex mixtures of biocides (preservatives), surfactants, and other agents designed to disinfect, clean, and wet contact lenses. The commercialization of silicone hydrogel (SiHy) lenses has resulted in unique challenges to the manufacturers of contact lens solutions, because the properties of these materials differ markedly from those seen previously with poly-hydroxyethyl methacrylate-based hydrogels. Historically, hydrogel lens uptake and release of low-molecular weight preservatives such as chlorhexidine and thimerosal were known to result in allergic reactions, resulting in corneal irritation, stinging, conjunctival hyperemia, development of corneal infiltrates, palpebral lid changes, and corneal staining. However, little is known about the interaction of modern care systems with modern soft lens materials. Factors to be considered when evaluating the uptake and release of care components include the water content, charge, relative hydrophobicity, surface treatment, and porosity of the lens material, in conjunction with the concentration, charge/molecule, ionicity in the product matrix, molecular weight, and hydrophobicity of the care component in question. These factors control the sorption of the solution components by lenses, resulting in a variety of differences in the amount of the component taken up into the lens material and the amount and rate of subsequent release onto the ocular surface. Because both natural (ocular) and environmental biota become part of the solution-lens system during regimen use of any lens care product, these extraneously introduced substances should also be considered regarding their potential for uptake and either subsequent release onto the ocular surface or functioning as a scaffold for the adhesion of microbes. This article will review current knowledge concerning these interactions and investigate what clinically observable complications may arise from these interactions. It also reviews whether current methods to determine these interactions could be improved on. © 2013 Lippincott Williams & Wilkins.

Keech,A., Senchyna,M., Jones,L. Impact of time between collection and collection method on human tear fluid osmolarity. Current eye research 2013;38,4:428-436. [ Show Abstract ]

Aim: To generate data on the variability of tear osmolarity in a control (normal, non-dry eye) and symptomatic dry eye population (Ocular Surface Disease Index: OSDI ≥20). A secondary outcome is the determination of the effect that tear collection technique has on the osmolarity of the sample. Materials and methods: This was a two-phase study that recruited 20 subjects (n = 10 normal, n = 10 dry eye) to evaluate the influence of time between measurements (Phase I) and 30 subjects (n = 15 normal, n = 15 dry eye) to evaluate the influence of collection technique (Phase II). As part of Phase I, serial tear osmolarity measurements were performed on each eye; four separated by 15min followed by four separated by lmin, at each of three visits. Phase II compared the consecutive measurement of four in vivo tear samples to four in vitro measurements on tears collected and dispensed from a glass capillary tube. Results: During Phase I, the dry eye group had a significantly higher maximum osmolarity (334.2 ± 25.6 mOsm/L) compared to the normal group (304.0 ± 8.4mOsm/L, p = 0.002). No significant differences were observed whether collections were performed at 15 or 1 min intervals. During Phase II, the in vivo osmolarity was equivalent to in vitro measurements from glass capillary tube samples for both the dry eye group (323.0± 16.7mOsm/L versus 317.7±24.8, p = 0.496), and for the normal subjects (301.2±7. 2mOsm/L versus 301.9 ± 16.0 mOsm/L, p = 0.884). Conclusion: Symptomatic dry eye subjects exhibited a significantly higher tear osmolarity and variation over time than observed in normal subjects, reflecting the inherent tear film instability of dry eye disease. There was no change in the distribution of tear osmolarity measurements whether tears were collected in rapid succession or given time to equilibrate, and collection method had no impact on tear osmolarity. © Informa Healthcare USA Inc.

Keir,N., Jones,L. Wettability and silicone hydrogel lenses: A review. Eye and Contact Lens 2013;39,1:100-108. [ Show Abstract ]

One of the major breakthroughs in the development of silicone hydrogel contact lenses has related to the ability of manufacturers to overcome the surface hydrophobicity that occurred with silicone elastomer lenses. However, the wettability of silicone hydrogel lenses continues to be of interest as a potential link between in vivo lens performance and contact lens-related comfort. This article will review some of the knowledge we have gained in the area of contact lens wettability over the past decade and will discuss some of the challenges related to its measurement. © 2013 Lippincott Williams & Wilkins.

Ng,A., Heynen,M., Luensmann,D., Subbaraman,L. N., Jones,L. Impact of tear film components on the conformational state of lysozyme deposited on contact lenses. Journal of Biomedical Materials Research - Part B Applied Biomaterials 2013;101,7:1172-1181. [ Show Abstract ]

Purpose To investigate the impact of lactoferrin and lipids on the kinetic denaturation of lysozyme deposited on silicone and conventional hydrogel lenses, using a complex artificial tear solution (ATS). Methods Two silicone hydrogel lenses (AIR OPTIX AQUA; lotrafilcon B and ACUVUE OASYS; senofilcon A) and two conventional hydrogel lenses (ACUVUE 2; etafilcon A and PROCLEAR; omafilcon A) were incubated in four solutions: an ATS, ATS without lactoferrin, ATS without lipids, and ATS without lactoferrin and lipids. At various time points over a 28-day period, the percentage of active lysozyme per lens was determined using a fluorescence activity assay and an ELISA. Results After 28 days, the percentage of active lysozyme extracted from etafilcon A lenses in all solutions was significantly higher than all other lens materials (p 0.05). The inclusion of lipids in the ATS significantly increased the lysozyme denaturation on both silicone hydrogel materials (p 0.05). The inclusion of lipids in the ATS significantly increased the lysozyme denaturation on both silicone hydrogel materials (p 0.05). Conclusions Lactoferrin and lipids have an impact on the denaturation of lysozyme deposited onto silicone hydrogel contact lenses, while conventional hydrogel lenses were unaffected. Future in vitro studies should consider the impact of tear film components when investigating protein deposition and denaturation on contact lenses. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 1172-1181, 2013. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

Ng,A., Heynen,M., Luensmann,D., Subbaraman,L. N., Jones,L. Optimization of a fluorescence-based lysozyme activity assay for contact lens studies. Current eye research 2013;38,2:252-259. [ Show Abstract ]

Purpose: To optimize a fluorescence-based lysozyme activity assay to investigate the conformational state of lysozyme in solution and to determine the impact of extraction and evaporation procedures and the possible interference of contact lens materials on lysozyme activity. Methods: The fluorescence-based lysozyme activity assay, Enzchek (Molecular Probes Inc, Eugene, OR) which utilizes fluorescently quenched Micrococcus lysodeikticus, was compared to the gold standard, classical lysozyme turbidity assay, using four differently concentrated lysozyme samples (20, 10, 5.0 and 2.0 ng/µL). Furthermore, six differently concentrated lysozyme samples (2.0, 1.0, 0.5, 0.25, 0.125 and 0.01 µg/µL) were quantified using the fluorescence-based assay in the presence of extraction solvents consisting of 0.2% and 0.02% trifluroacetic acid/acetonitrile and following evaporation procedures. Results: A standard curve was generated by the fluorescence-based assay ranging from 2 to 150 ng. The total active lysozyme quantified in the four lysozyme samples was not significantly different between the two assays (p > 0.05) and the concordance correlation coefficient was determined to be 0.995. However an average discrepancy between the two assays was found to be 0.474 ng, with the turbidity assay typically reporting higher active lysozyme measurements. The sensitivity of the fluorescence-based assay was higher than the classical turbidity assay when quantifying 20 ng or less active lysozyme. Following the extraction and evaporation procedures and the addition of lens extracts, the total active lysozyme recovered was 95% or greater. Conclusions: In comparison to the classical turbidity assay, the fluorescence-based assay is a very sensitive method, making it a favorable technique, particularly when studying contact lens materials that deposit relatively low levels of lysozyme. © Informa Healthcare USA, Inc.

Ngo,W., Srinivasan,S., Jones,L. Historical overview of imaging the meibomian glands. Journal of Optometry 2013;6,1:1-8. [ Show Abstract ]

Growing knowledge of the role of the meibomian glands in dry eye disease and contact lens discomfort has resulted in a surge of interest in visualizing these glands within the eyelids. This manuscript provides an overview of the many different visualization methods that have evolved over the past 30-40 years. Some of the visualization methods covered in this review include lid transillumination, video and non-contact meibography, and imaging methods employing confocal microscopy, optical coherence tomography and ultrasound. This review has also highlighted all the studies to date that have employed meibography as part of their methods. An overview of the available meibography dropout grading systems will also be provided. © 2012 Spanish General Council of Optometry.

Nichols,J. J., Jones,L., Daniel Nelson,J., Stapleton,F., Sullivan,D. A., Willcox,M. D. P. The TFOS International Workshop on Contact Lens Discomfort: Introduction. Investigative Ophthalmology and Visual Science 2013;54,11:TFOS1-TFOS6.

Nichols,J. J., Willcox,M. D. P., Bron,A. J., Belmonte,C., Ciolino,J. B., Craig,J. P., Dogru,M., Foulks,G. N., Jones,L., Nelson,J. D., Nichols,K. K., Purslow,C., Schaumberg,D. A., Stapleton,F., Sullivan,D. A. The TFOS International Workshop on Contact Lens Discomfort: Executive summary. Investigative Ophthalmology and Visual Science 2013;54,11:TFOS7-TFOS13.

Phan,C. -M, Subbaraman,L. N., Jones,L. In vitro uptake and release of natamycin from conventional and silicone hydrogel contact lens materials. Eye and Contact Lens 2013;39,2:162-168. [ Show Abstract ]

OBJECTIVES:: To investigate the uptake and release of the antifungal ocular drug, natamycin from commercially available conventional hydrogel (CH) and silicone hydrogel (SH) contact lens (CL) materials and to evaluate the effectiveness of this delivery method. METHODS:: Five commercial SH CLs (balafilcon A, comfilcon A, galyfilcon A, senofilcon A, and lotrafilcon B) and four CH CLs (etafilcon A, omafilcon A, polymacon, vifilcon A) were examined in this study. These lenses were incubated with natamycin solubilized in dimethyl sulfoxide, and the release of the drug from these lenses, in Unisol 4 pH 7.4 at 32±1 C, was determined using UV-visible spectrophotometry at 305 nm over 24 hours. RESULTS:: There was a significant uptake of natamycin between 0 hour and 24 hours (P0.05). There was a significant difference in release between all the SH materials (P0.05). There was a significant difference in release between all the SH materials (P0.05). There was a significant difference in release between all the SH materials (P0.05). Overall, the release of natamycin was higher in CH than SH lenses (P<0.001). CONCLUSIONS:: All CLs released clinically relevant concentrations of natamycin within 30 minutes, but this release reached a plateau after approximately 1 hour. Further CL material development will be necessary to produce a slow and sustained drug releasing device for the delivery of natamycin. © 2013 Lippincott Williams & Wilkins.

Srinivasan,S., Heynen,M. L., Martell,E., Ritter III,R., Jones,L., Senchyna,M. Quantification of MUCIN 1, cell surface associated and MUCIN16, cell surface associated proteins in tears and conjunctival epithelial cells collected from postmenopausal women. Molecular Vision 2013;19970-979. [ Show Abstract ]

Purpose: To quantify the expression of mucin 1, cell surface associated (MUC1) and mucin 16, cell surface associated (MUC16) proteins and messenger ribonucleic acid (mRNA) in a cohort of postmenopausal women (PMW), to explore the relationship between mucin expression, dry eye symptomology, and tear stability. Methods: Thirty-nine healthy PMW (>50 years of age) were enrolled in this study. No specific inclusion criteria were used to define dry eye; instead, a range of subjects were recruited based on responses to the Allergan Ocular Surface Disease Index (OSDI) questionnaire and tear stability measurements as assessed by non-invasive tear breakup time (NITBUT). Tears were collected from the inferior tear meniscus using a disposable glass capillary tube, and total RNA and total protein were isolated from conjunctival epithelial cells collected via impression cytology. Expression of membrane-bound and soluble MUC1 and MUC16 were quantified with western blotting, and expression of MUC1 and MUC16 mRNA was assessed with real-time PCR. Results: OSDI responses ranged from 0 to 60, and NITBUT ranged from 18.5 to 2.9 s. Only two statistically significant correlations were found: soluble MUC16 protein concentration and MUC16 mRNA expression with OSDI vision related (-0.47; p=0.01) and ocular symptom (0.39; p=0.02) subscores, respectively. Post hoc exploratory analysis on absolute expression values was performed on two subsets of subjects defined as asymptomatic (OSDI =6, n=12) and moderate to severe symptomatic (OSDI =20, n=12). The only significant difference between the two subgroups was a significant reduction in MUC16 mRNA expression found in the symptomatic dry eye group (1.52±1.19 versus 0.57±0.44; p=0.03). Conclusions: A broad exploration of mucin expression compared to either a sign (NITBUT) or symptoms of dry eye failed to reveal compelling evidence supporting a significant relationship, other than a potential association between MUC16 with specific symptoms. Furthermore, comparison of mucin protein and expression levels between the asymptomatic and moderate to severe symptomatic subgroups revealed only one significant difference, a reduction in MUC16 mRNA expression in the symptomatic subgroup. © 2013 Molecular Vision.

Srinivasan,S., Menzies,K. L., Sorbara,L., Jones,L. W. Imaging meibomian glands on a patient with chalazia in the upper and lower lids: A case report. Contact Lens and Anterior Eye 2013;36,4:199-203. [ Show Abstract ]

Aim: To describe the meibomian gland (MG) appearance in a case of eyelid chalazia, using a novel meibography method. Methods: A 29-year-old female of South Asian origin presented with mild swelling in the lower lid of the left eye. The patient also presented with a history of a recurrent chalazion in the upper lid of the same eye, which later progressed to an active chalazion. A chalazion also developed in the upper lid of the right eye. Meibography was performed using a novel Keratograph (Keratograph 4, OCULUS, Wetzlar, Germany) to evaluate the structure of the MG in the area affected by the chalazia. Results: The area of the recurrent chalazion in the upper left lid showed partial and/or complete MG loss. The active chalazia in the lower left lid and the upper right lid showed inflammation and MG drop out at the affected site. The inflammation was found to be reduced during the follow-up visits, however disappearance of MG very specific to the region of the chalazion was observed. Conclusion: The Keratograph 4 was able to image the MG structures clearly, allowing the clinician to monitor the progression of chalazia and the MG loss in the affected areas. © 2013 British Contact Lens Association.

Varikooty,J., Keir,N., Richter,D., Jones,L. W., Woods,C., Fonn,D. Comfort response of three silicone hydrogel daily disposable contact lenses. Optometry and Vision Science 2013;90,9:945-953. [ Show Abstract ]

PURPOSE: To evaluate subjective ocular comfort across the day with three silicone hydrogel daily disposables (SHDDs) in a group of adapted lens wearers. METHODS: Masked subjects (asymptomatic or symptomatic of end-of-day (EOD) dryness with habitual lenses) wore three SHDDs: DAILIES TOTAL1 (DT1), Clariti 1day (C1D), or 1-DAY ACUVUE TRUEYE (AVTE), each for 3 days. On day 2, wearing time (WT) and comfort ratings after insertion, at 4, 8, and 12 hours, and at EOD were recorded. Because not all subjects wore lenses for 12 hours, comfort was analyzed across the day (up to 8 hours, 8 to 12 hours), and a new variable ("cumulative comfort" [CC]) was calculated for EOD. RESULTS: One hundred four subjects completed the study (51 asymptomatic, 53 symptomatic). The two groups had different WTs (mean WT, 14.0 and 12.7 hours, respectively; p < 0.001). Ocular comfort was rated higher in the asymptomatic group throughout the day (p < 0.001). One hundred four subjects wore all three SHDDs for at least 8 hours, whereas 74 (45 asymptomatic, 29 symptomatic) subjects wore them for 12 hours or longer. Comfort ratings were higher with DT1 (least square means [LSM] = 91.0) than with C1D (LSM = 86.5; p < 0.001) and AVTE (LSM = 87.7; p = 0.011) for the first 8 hours and lower with C1D compared with DT1 (p = 0.012) from 8 to 12 hours. Mean EOD (± SD) comfort with the C1D lens was 72 ± 21, lower than both DT1 (mean, 79 ± 17; p = 0.001) and AVTE (mean, 78 ± 21; p = 0.010). Mean CC was higher in the asymptomatic group (mean, 1261 ± 59) compared with that in the symptomatic group (mean, 1009 ± 58; p < 0.001) and higher for DT1 (mean, 1184 ± 258) than C1D (mean, 1094 ± 318; p = 0.002) and AVTE (mean, 1122 ± 297; p = 0.046). CONCLUSIONS: All three SHDDs had average WTs of 12 hours or longer for 1 day. Comfort during the first 12 hours was highest with DT1 (similar to AVTE between 8 and 12 hours) and lowest with C1D. End-of-day comfort was lowest with C1D, and CC was highest for DT1. Cumulative comfort may be a valuable new metric to assess ocular comfort during the day. © 2013 American Academy of Optometry.

Walther,H., Lorentz,H., Heynen,M., Kay,L., Jones,L. W. Factors that influence in vitro cholesterol deposition on contact lenses. Optometry and Vision Science 2013;90,10:1057-1065. [ Show Abstract ]

PURPOSE: The purpose of this study was to analyze the impact that incubation time, lipid concentration, and solution replenishment have on silicone hydrogel (SiHy) and conventional hydrogel (CH) contact lens cholesterol deposition via in vitro radiochemical experiments. METHODS: Four SiHy (senofilcon A, lotrafilcon B, comfilcon A, balafilcon A) and two CH (etafilcon A and omafilcon A) contact lenses were incubated in an artificial tear solution (ATS) that contained major tear film proteins, lipids, salts, salts, and a trace amount of radioactive C-cholesterol. Lenses were incubated for various incubation times (1, 3, 7, 14, or 28 days), with three concentrations of lipid (0.5×, 1×, 2× tear film concentration) and with or without solution replenishment to assess each variable's impact on cholesterol deposition. After incubation, the lenses were extracted using 2:1 chloroform:methanol, extracts were analyzed in a beta counter and masses (micrograms per lens) were extrapolated from standard curves. RESULTS: Within the SiHy materials, balafilcon A deposited the greatest amount of cholesterol (p replenishing > 1× > 0.5×. CONCLUSIONS: Overall, SiHy lenses deposit significantly more cholesterol than CH lens materials, and the mass of lipid deposited is dependent on the contact lens material, length of incubation, concentration of lipids in the ATS, and the replenishment of ATS. Copyright © 2013 American Academy of Optometry.

2012

Weeks,A., Morrison,D., Alauzun,J. G., Brook,M. A., Jones,L., Sheardown,H. Photocrosslinkable hyaluronic acid as an internal wetting agent in model conventional and silicone hydrogel contact lenses. Journal of Biomedical Materials Research - Part A 2012;100 A,8:1972-1982. [ Show Abstract ]

Photocrosslinkable methacrylated hyaluronic acid (HA) was prepared and incorporated into model conventional and silicone hydrogel contact lenses as an internal wetting agent. The molecular weight of the HA, the degree of methacrylation as well as the amount (0.25 to 1.0 wt %) incorporated were varied. The HA-containing hydrogels were analyzed using a variety of techniques including water contact angles, equilibrium water content (EWC), and lysozyme sorption. The presence of HA could be detected in the materials using X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopya - attenuated total reflectance. The materials containing methacrylated HA had improved hydrophilicity and reduced lysozyme sorption. Effects of modified HA on EWC were dependent upon the materials but generally increased water uptake. Increased mobility of the HA associated with a lower molecular weight and lower degree of methacrylation was found to be more effective in improving hydrophilicity and decreasing lysozyme sorption than the less mobile HA. All results found suggest that photocrosslinkable HA has significant potential in contact lens applications. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012. Copyright © 2011 Wiley Periodicals, Inc.

Weeks,A., Subbaraman,L. N., Jones,L., Sheardown,H. The competing effects of hyaluronic and methacrylic acid in model contact lenses. Journal of Biomaterials Science, Polymer Edition 2012;23,8:1021-1038. [ Show Abstract ]

The aim of this study was to determine the influence of hyaluronic acid (HA) on lysozyme sorption in model contact lenses containing varying amounts of methacrylic acid (MAA). One model conventional hydrogel (poly(2-hydroxyethyl methacrylate) (pHEMA)) and two model silicone hydrogels (pHEMA, methacryloxypropyltris(trimethylsiloxy)silane (pHEMA TRIS) and N,N-dimethylacrylamide, TRIS (DMAA TRIS)) lens materials were prepared with and without MAA at two different concentrations (1.7 and 5%). HA, along with dendrimers, was loaded into these model contact lens materials and then cross-linked with 1-ethyl-3-(3-dimethylamino propyl)-carbodiimide (EDC). Equilibrium water content (EWC), advancing water contact angle and lysozyme sorption on these lens materials were investigated. In the HA-containing materials, the presence (P < 0.05) and amount (P < 0.05) of MAA increased the EWC of the materials. For most materials, addition of MAA reduced the advancing contact angles (P < 0.05) and for all the materials, the addition of HA further improved hydrophilicity (P < 0.05). For the non-HA containing hydrogels, the presence (P < 0.05) and amount (P < 0.05) of MAA increased lysozyme sorption. The presence of HA decreased lysozyme sorption for all materials (P < 0.05). MAA appears to work synergistically with HA to increase the EWC in addition to improving the hydrophilicity of model pHEMA-based and silicone hydrogel contact lens materials. Hydrogel materials that contain HA have tremendous potential as hydrophilic, protein-resistant contact lens materials. © Koninklijke Brill NV, Leiden, 2012.

Woods,J., Jones,L., Woods,C., Schneider,S., Fonn,D. Use of a photographic manipulation tool to assess corneal vascular response. Optometry and Vision Science 2012;89,2:215-220. [ Show Abstract ]

Purpose. Corneal vasculature change in contact lens wearers has been linked to the level of hypoxia within the cornea. To assess the impact a treatment has on limbal vessels, a sensitive method of measurement and quantification is required. Methods. A group of 21 highly myopic, hydrogel wearers, with preexisting signs of corneal hypoxia, were enrolled into a study where they wore sifilcon A silicone hydrogel lenses (Dk/t = 117), on a daily wear basis for 9 months. At all scheduled visits, photographs were taken of the superior, inferior, temporal, and nasal limbal regions which were then imported into Adobe Photoshop. A red-free filter was applied to enhance the contrast of the blood columns. In each quadrant, the length of the longest visible blood column was measured and the blood columns that penetrated -0.5 mm into the cornea were counted. A control group of 11 non-lens wearers was recruited. Their photographs were taken at the beginning of the study and 9 months later. An independent, masked observer assessed the photographs. Results. There was a significant decrease in the maximum penetration of the blood column in all quadrants (p + 0.001) from baseline to the 9-month visit (e.g., superior: baseline 0.84 ± 0.39 mm; 9 months 0.63 ± 0.20 mm). There was also significant reduction in the number of visible blood columns longer than 0.5 mm in each quadrant (p + 0.001) from baseline to 9 months in all quadrants (e.g., superior: baseline 14.0 ± 8.2; 9 months 6.5 ± 6.0). The control group showed no change over time for the maximum blood column length (p = 0.638) or the number of columns >0.5 mm (p = 0.341). Conclusions. A group of highly myopic subjects exhibited reduction in the maximum length and number of blood columns in the cornea when refit with a highly permeable silicone hydrogel material. The use of photography, along with Adobe Photoshop software, provides a reliable way of measuring corneal vascular responses over time. (Optom Vis Sci 2012;89:215-220). © 2012 American Academy of Optometry.

Dumbleton,K., Woods,C. A., Jones,L. W., Fonn,D. The impact of contemporary contact lenses on contact lens discontinuation. Eye and Contact Lens 2012. [ Show Abstract ]

OBJECTIVES: Discontinuation or "dropout" from contact lens (CL) wear continues to afflict the CL industry. This study was conducted to determine whether the advent of new CL materials and designs has impacted the dropout rate and the reasons for discontinuation. METHODS: Current and lapsed CL wearers residing in Canada were recruited using Facebook to take part in an on line survey investigating CL wearing experiences during 2008 to 2010 and to establish the percentage of participants who temporarily and permanently discontinued CL wear during the period surveyed. RESULTS: Four thousand two hundred seven eligible surveys were received (64% female; median age 27 years). Forty percent had lapsed from lens wear for at least 4 months; however, 62% of the lapsed wearers (LWs) resumed wear. There were no differences between LWs and nonlapsed wearers (NLWs) with respect to gender; however, LWs were older, started lens wear when older, and had not worn lenses for as long as NLWs (all P<0.001). More NLWs than LWs wore silicone hydrogel CLs (49% vs. 38%, P<0.001) and more LWs than NLWs wore daily disposable lenses and hydrogel CLs (24% vs. 19% and 22% vs. 18%, respectively, P≤0.001). Primary reasons for discontinuation were discomfort (24%), dryness (20%), red eyes (7%), and expense (7%). Compliance with lens replacement was no different between LWs and NLWs (48% vs. 45%). CONCLUSIONS: About 23% of those surveyed had discontinued CL wear permanently. The primary reasons for dropping out continue to be discomfort and dryness. Dropout rates were lower in silicone hydrogel wearers.

Hui,A., Sheardown,H., Jones,L. Acetic and acrylic acid molecular imprinted model silicone hydrogel materials for ciprofloxacin-HCL delivery. 2012;5,1:85-107. [ Show Abstract ]

Contact lenses, as an alternative drug delivery vehicle for the eye compared to eye drops, are desirable due to potential advantages in dosing regimen, bioavailability and patient tolerance/compliance. The challenge has been to engineer and develop these materials to sustain drug delivery to the eye for a long period of time. In this study, model silicone hydrogel materials were created using a molecular imprinting strategy to deliver the antibiotic ciprofloxacin. Acetic and acrylic acid were used as the functional monomers, to interact with the ciprofloxacin template to efficiently create recognition cavities within the final polymerized material. Synthesized materials were loaded with 9.06 mM, 0.10 mM and 0.025 mM solutions of ciprofloxacin, and the release of ciprofloxacin into an artificial tear solution was monitored over time. The materials were shown to release for periods varying from 3 to 14 days, dependent on the loading solution, functional monomer concentration and functional monomer:template ratio, with materials with greater monomer:template ratio (8:1 and 16:1 imprinted) tending to release for longer periods of time. Materials with a lower monomer:template ratio (4:1 imprinted) tended to release comparatively greater amounts of ciprofloxacin into solution, but the release was somewhat shorter. The total amount of drug released from the imprinted materials was sufficient to reach levels relevant to inhibit the growth of common ocular isolates of bacteria. This work is one of the first to demonstrate the feasibility of molecular imprinting in model silicone hydrogel-type materials.

Jadi,S., Heynen,M., Luensmann,D., Jones,L. Composition of incubation solution impacts in vitro protein uptake to silicone hydrogel contact lenses. Molecular Vision 2012;18337-347. [ Show Abstract ]

Purpose: To determine the impact of incubation solution composition on protein deposition to silicone hydrogel (SH) contact lenses using a simplistic and a complex model of the tear film. Methods: Three SH materials - senofilcon A (SA), lotrafilcon B (LB), and balafilcon A (BA) - were incubated in two different solutions; Solution A was a simplistic augmented buffered saline solution containing a single protein, whereas Solution B was a complex artificial tear solution (ATS), containing the augmented buffered saline solution in addition to proteins, lipids, and mucins (pH=7.4). The proteins of interest (lysozyme, lactoferrin, albumin) were radiolabeled with Iodine-125 (2% protein of interest) and the accumulation of the conjugated protein to the lens materials was determined after 1, 7, 14, and 28 days of incubation. Protein deposition was measured using a gamma counter and the raw data were translated into absolute amounts (μg/lens) via extrapolation from standards. Results: After 28 days, lysozyme uptake was significantly lower on BA lenses when incubated in Solution A (33.7 μg) compared to Solution B (56.2 μg), p0.05. LB lenses also deposited similar amounts of lysozyme for both solutions (Solution A: 5.0 μg, Solution B: 4.7 μg, p>0.05). After 28 days, BA lenses accumulated approximately twice the amount of lactoferrin than the other lens materials, with 30.3 μg depositing when exposed to Solution A and 22.0 μg with Solution B. The difference between the two solutions was statistically significant (p0.05. LB lenses also deposited similar amounts of lysozyme for both solutions (Solution A: 5.0 μg, Solution B: 4.7 μg, p>0.05). After 28 days, BA lenses accumulated approximately twice the amount of lactoferrin than the other lens materials, with 30.3 μg depositing when exposed to Solution A and 22.0 μg with Solution B. The difference between the two solutions was statistically significant (p0.05). After 28 days, albumin deposition onto BA lenses was significantly greater when lenses were incubated in Solution B (1.7 μg) compared to Solution A (0.9 μg), p0.05). LB lenses incubated in Solution A deposited more albumin compared to Solution B (0.9 μg versus 0.6 μg), p=0.003. Discussion: Protein deposition onto SH materials varied when contact lenses were incubated in either a complex ATS compared to a single protein solution. More lysozyme accumulated onto BA lenses incubated in a complex analog of the human tear film, whereas lactoferrin deposited onto SA lenses independent of incubation solution composition. To better mimic the ex vivo environment, future studies should use more appropriate analogs of the tear film. © 2012 Molecular Vision.

Leiske,D. L., Leiske,C. I., Leiske,D. R., Toney,M. F., Senchyna,M., Ketelson,H. A., Meadows,D. L., Srinivasan,S., Jones,L., Fuller,G. G. Temperature-induced transitions in the structure and interfacial rheology of human meibum. Biophysical journal 2012;102,2:369-376. [ Show Abstract ]

Meibomian lipids are the primary component of the lipid layer of the tear film. Composed primarily of a mixture of lipids, meibum exhibits a range of melt temperatures. Compositional changes that occur with disease may alter the temperature at which meibum melts. Here we explore how the mechanical properties and structure of meibum from healthy subjects depend on temperature. Interfacial films of meibum were highly viscoelastic at 17°C, but as the films were heated to 30°C the surface moduli decreased by more than two orders of magnitude. Brewster angle microscopy revealed the presence of micron-scale inhomogeneities in meibum films at higher temperatures. Crystalline structure was probed by small angle x-ray scattering of bulk meibum, which showed evidence of a majority crystalline structure in all samples with lamellar spacing of 49 that melted at 34°C. A minority structure was observed in some samples with d-spacing at 110 that persisted up to 40°C. The melting of crystalline phases accompanied by a reduction in interfacial viscosity and elasticity has implications in meibum behavior in the tear film. If the melt temperature of meibum was altered significantly from disease-induced compositional changes, the resultant change in viscosity could alter secretion of lipids from meibomian glands, or tear-film stabilization properties of the lipid layer. © 2012 Biophysical Society.

Leiske,D. L., Miller,C. E., Rosenfeld,L., Cerretani,C., Ayzner,A., Lin,B., Meron,M., Senchyna,M., Ketelson,H. A., Meadows,D., Srinivasan,S., Jones,L., Radke,C. J., Toney,M. F., Fuller,G. G. Molecular structure of interfacial human meibum films. Langmuir 2012;28,32:11858-11865. [ Show Abstract ]

Meibum is the primary component of the tear film lipid layer. Thought to play a role in tear film stabilization, understanding the physical properties of meibum and how they change with disease will be valuable in identifying dry eye treatment targets. Grazing incidence X-ray diffraction and X-ray reflectivity were applied to meibum films at an air-water interface to identify molecular organization. At room temperature, interfacial meibum films formed two coexisting scattering phases with rectangular lattices and next-nearest neighbor tilts, similar to the Ov phase previously identified in fatty acids. The intensity of the diffraction peaks increased with compression, although the lattice spacing and molecular tilt angle remained constant. Reflectivity measurements at surface pressures of 18 mN/m and above revealed multilayers with d-spacings of 50 Å, suggesting that vertical organization rather than lateral was predominantly affected by meibum-film compression. © 2012 American Chemical Society.

Liu,S., Jones,L., Gu,F. X. Development of Mucoadhesive Drug Delivery System Using Phenylboronic Acid Functionalized Poly(D,L-lactide)-b-Dextran Nanoparticles. Macromolecular Bioscience 2012;12,12:1622-1626. [ Show Abstract ]

Mucoadhesive NP drug carriers have attracted substantial interest as a potential treatment for anterior eye diseases. NPs composed of PLA-Dex surface functionalized with a mucoadhesive ligand, PBA, were developed as drug carriers with particle sizes ranging from 25 to 28nm. Using CycA as a model drug, we showed that NPs encapsulated up to 13.7wt% CycA and exhibited sustained release for up to 5 d in vitro at a clinically relevant dose. We fine-tuned the PBA density on the NP surface to maximize the mucin-NP interaction without compromising the particle stability in vitro. This block copolymer conjugate may be useful to improve the bioavailability of topical formulations. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lorentz,H., Heynen,M., Khan,W., Trieu,D., Jones,L. The impact of intermittent air exposure on lipid deposition. Optometry and Vision Science 2012;89,11:1574-1581. [ Show Abstract ]

PURPOSE: To analyze the impact of intermittent air exposure on the in vitro deposition of two radioactive lipids on various contact lens (CL) materials, using a custom-designed model blink cell. METHODS: Six different CL materials (balafilcon A, lotrafilcon B, comfilcon A, senofilcon A, etafilcon A, and omafilcon A) were mounted on the model blink cell pistons, which cycled the lenses in and out of a complex artificial tear solution (ATS) that contained a trace amount of C-cholesterol or C-phosphatidylcholine. For the short-term experiment, air-exposed lenses were continuously cycled in and out of the ATS for 10 h. Longer term incubations for 6 days were tested with lotrafilcon B and balafilcon A materials incubated in C-cholesterol ATS. The air-exposed CLs were cycled for 14 h then submerged for 10 h each day. For both experiments, the control lenses were submerged for the entire test period. After incubation, lenses were processed, and deposited masses were quantified. RESULTS: Exposure to air resulted in increased amounts of cholesterol deposited by 1.6 to 4.3 fold on omafilcon A, balafilcon A, comfilcon A, and senofilcon A (p ≤ 0.03) compared with submerged lenses. No differences in deposition were observed for etafilcon A and lotrafilcon B (p > 0.05). The longer term incubation of lotrafilcon B and balafilcon A showed statistically significant increases in cholesterol deposition for both air-exposed lens materials (p 0.05). CONCLUSIONS: This study found that lipid deposition profiles are CL material dependent and that intermittent air exposure can influence the mass of lipid deposited. Copyright © 2012 American Academy of Optometry.

Lorentz,H., Heynen,M., Tran,H., Jones,L. Using an in vitro model of lipid deposition to assess the efficiency of hydrogen peroxide solutions to remove lipid from various contact lens materials. Current eye research 2012;37,9:777-786. [ Show Abstract ]

Purpose: To test the ability of two commercially available hydrogen peroxide disinfection solutions, one containing a surfactant and one without, to remove lipid from various contact lens materials using in vitro radiochemical experiments. Methods: Etafilcon A, senofilcon A and balafilcon A contact lens materials were incubated in an artificial tear solution (ATS) containing a mixture of lipids, proteins, mucin and either 14C-cholesterol or 14C-phosphatidylcholine for 8 h. Following incubation, the lenses were removed, rinsed, and placed for 16 h in either a surfactant-containing peroxide solution (ClearCare ®), a peroxide solution devoid of a surfactant (AOSept ®) or stored without solution (control). This process was repeated every day for 1 week. The lenses were extracted with a previously optimized extraction protocol, evaporated, re-suspended, fluor added and counted for their radioactive signals. Masses of lipids deposited were calculated based on standard calibration curves, the disinfection solutions were compared and repeated measures ANOVA and post hoc statistical analysis was completed using Statistica 9. Results: The results of this experiment found that daily disinfection with hydrogen peroxide solutions reduced the amount of cholesterol and phosphatidylcholine deposited on the three contact lens materials examined, however in many cases the reduction in deposition was less than 15% when compared to the control. Disinfection with the solution containing the surfactant (ClearCare), resulted in the least deposited cholesterol and phosphatidylcholine for all materials, however not all of the comparisons were statistically significant. Conclusions: Overall, ClearCare hydrogen peroxide disinfection solution containing Pluronic 17R4 removed the most lipid from lenses when compared to the non-surfactant containing AOSept or the control, for both lipids and all lens materials. However, the differences found were quite small at times and whether these differences are clinically significant are yet to be determined. © 2012 Informa Healthcare USA, Inc.

Lorentz,H., Heynen,M., Trieu,D., Hagedorn,S. J., Jones,L. The impact of tear film components on in vitro lipid uptake. Optometry and Vision Science 2012;89,6:856-867. [ Show Abstract ]

Purpose. To analyze the influence of various tear film components on in vitro deposition of two lipids (cholesterol and phosphatidylcholine) on three contact lens materials. Methods. Etafilcon A, balafilcon A, and senofilcon A were incubated in four different incubation solutions for 3 or 14 days: an artificial tear solution containing lipids and proteins, a protein tear solution containing proteins and the lipid of interest, a lipid tear solution containing lipids and no proteins, and a single lipid tear solution containing the lipid of interest only. Each incubation solution contained one of the two radiolabeled lipids: C-cholesterol (C) or C-phosphatidylcholine (PC). After soaking, lenses were removed from the incubation solution, the lipids were extracted and quantified using a beta counter, and masses of lipid were calculated using standard calibration curves. Results. This experiment examined several different parameters influencing lipid deposition on contact lenses, including lens material, length of incubation, and the composition of the incubation solution. Overall, lipid deposited differently on different lens materials (p senofilcon > etafilcon. Incubation solution had a large impact on how much lipid was deposited (p < 0.00001), although cholesterol and phosphatidylcholine demonstrated different deposition patterns. Lipid deposition after 14 days of incubation was consistently greater than after 3 days (p < 0.02). Conclusions. This in vitro study demonstrates that C and PC deposition are cumulative over time and that silicone hydrogel materials deposit more lipid than group IV conventional hydrogel materials. It also clearly demonstrates that deposition of C and PC is influenced by the composition of the incubation solution and that in vitro models must use more physiologically relevant incubation solutions that mimic the natural tear film if in vitro data is to be extrapolated to the in vivo situation. © 2012 American Academy of Optometry.

Luensmann,D., Jones,L. Protein deposition on contact lenses: The past, the present, and the future. Contact Lens and Anterior Eye 2012;35,2:53-64. [ Show Abstract ]

Proteins are a key component in body fluids and adhere to most biomaterials within seconds of their exposure. The tear film consists of more than >400 different proteins, ranging in size from 10 to 2360 kDa, with a net charge of pH 1-11. Protein deposition rates on poly-2-hydroxyethyl methacrylate (pHEMA) and silicone hydrogel soft contact lenses have been determined using a number of ex vivo and in vitro experiments. Ionic, high water pHEMA-based lenses attract the highest amount of tear film protein (1300 μg/lens), due to an electrostatic attraction between the material and positively charged lysozyme. All other types of pHEMA-based lenses deposit typically less than 100 μg/lens. Silicone hydrogel lenses attract less protein than pHEMA-based materials, with <10 μg/lens for non-ionic and up to 34 μg/lens for ionic materials. Despite the low protein rates on silicone hydrogel lenses, the percentage of denatured protein is typically higher than that seen on pHEMA-based lenses. Newer approaches incorporating phosphorylcholine, polyethers or hyaluronic acid into potential contact lens materials result in reduced protein deposition rates compared to current lens materials. © 2012 British Contact Lens Association.

Ng,A., Heynen,M., Luensmann,D., Jones,L. Impact of tear film components on lysozyme deposition to contact lenses. Optometry and Vision Science 2012. [ Show Abstract ]

PURPOSE: To investigate the impact of lactoferrin and lipids on the kinetic deposition of lysozyme on silicone and conventional hydrogel lenses, using a complex artificial tear solution (ATS). METHODS: Two silicone hydrogel lenses (AIR OPTIX AQUA; lotrafilcon B and ACUVUE OASYS; senofilcon A) and two conventional hydrogel lenses (ACUVUE 2; etafilcon A and PROCLEAR; omafilcon A) were investigated. Lenses were incubated in four different solutions: a complex ATS consisting of various salts, lipids, proteins, and mucins, an ATS without lactoferrin (ATS w/o Lac), an ATS without lipids (ATS w/o Lip), and an ATS without lactoferrin and lipids (ATS w/o Lac & Lip), each containing 2% radiolabeled (125I) lysozyme (1.9 mg/ml). After each time point (4, 12 h and 1, 2, 3, 5, 7, 14, 21, 28 days), the amount of lysozyme per lens was quantified. RESULTS: After 28 days, lotrafilcon B lenses incubated in ATS deposited significantly less lysozyme (9.7 ± 1.4 μg) than when incubated in solutions not containing lactoferrin and lipids (more than 11.8 μg) (p < 0.001). Lysozyme uptake to senofilcon A lenses was higher in ATS w/o Lip (5.3 ± 0.1 μg) compared with other solutions (less than 3.9 μg) (p < 0.001). Etafilcon A lenses deposited the most lysozyme in all four solutions compared with the rest of the lens types (p < 0.001). For etafilcon A lenses, less lysozyme was deposited when incubated in ATS w/o Lip (588.6 ± 0.4 μg) compared with the other solutions (more than 642.6 μg) (p < 0.001). Omafilcon A lenses in ATS w/o Lac accumulated significantly less lysozyme (12.8 ± 1.0 μg) compared with the other solutions (more than 14.2 μg) (p < 0.001). CONCLUSIONS: An ATS containing lactoferrin and lipids impacts lysozyme deposition on both silicone and conventional hydrogel contact lenses. When performing in vitro experiments to study protein deposition on contact lenses, more complex models should be used to better mimic the human tear film.

Srinivasan,S., Menzies,K., Sorbara,L., Jones,L. Infrared imaging of meibomian gland structure using a novel keratograph. Optometry and Vision Science 2012;89,5:788-794. [ Show Abstract ]

PURPOSE.: To examine the ability of a novel non-contact device (Keratograph 4) to image the meibomian gland (MG) structures and their morphological changes in the upper and lower eyelids. METHODS.: Thirty-seven participants (mean age 57.8 ± 8.5 years; 3 males and 34 females) completed the Ocular Surface Disease Index questionnaire to assess dryness symptoms. Meibum secretion quality score, number of blocked gland orifices, and meibum expressibility scores were assessed. The lower lid (LL) and upper lid (UL) of all subjects were everted and images of the MGs were taken using the Keratograph 4 (OCULUS). A MG dropout score (MGDS) due to complete or partial gland loss of both lids was obtained using a subjective 4-grade scoring system, and digital analysis of the images using ImageJ was performed. Presence of tortuosity and visible acinar changes of the MGs were also noted. RESULTS.: MGDS for both lids was significantly positively correlated with the Ocular Surface Disease Index score (r = 0.51; p < 0.05). The MGDS determined using the digital grading was also significantly positively correlated (UL: r = 0.68, p < 0.05; LL: r = 0.42, p < 0.05). The sum of the MGDS for both lids using the subjective grading scale was significantly different between the non-MGD and MGD group (1.3 ± 1.0 vs. 3.1 ± 1.1; p = 0.0004). MGDS assessment using the digital grading was significantly different between non-MGD (UL = 6%, LL = 8%) and MGD group (UL = 32%, LL = 42%; p = 0.001). Tortuous MG was observed only on the UL in 6% of the participants. Visible acinar changes were noted in 40% of the study participants. CONCLUSIONS.: Infrared meibography is now possible in a clinical setting using commercially available devices, and meibography can help determine differences in MG structure in subjects symptomatic of dry eye. Copyright © 2012 American Academy of Optometry.

Subbaraman,L. N., Glasier,M. -A, Varikooty,J., Srinivasan,S., Jones,L. Protein deposition and clinical symptoms in daily wear of etafilcon lenses. Optometry and Vision Science 2012;89,10:1450-1459. [ Show Abstract ]

Purpose.: To determine the relationship between clinical signs and symptoms and protein deposition over 8 h of wear of etafilcon A lenses in symptomatic and asymptomatic contact lens wearers. Methods.: Thirty adapted soft contact lens wearers (16 symptomatic and 14 asymptomatic) were fitted with etafilcon A lenses. In vivo wettability, non-invasive tear break-up time, and subjective symptoms (vision, comfort, and dryness) were assessed at baseline and after 2, 4, 6, and 8 h. After 2, 4, 6, and 8 h time points, lenses were collected, and total protein, total lysozyme, and active lysozyme deposition were assessed. Results.: There was a significant reduction (p = 0.032) in the non-invasive tear break-up time at 8 h in both groups. In the symptomatic group, there was a significant reduction in subjective comfort and dryness ratings at 6 and 8 h measurement with respect to baseline (p 94% at 8 h). Pearson's correlations between subjective symptoms and protein deposition showed poor correlations for total protein/lysozyme and any subjective factor (r 0.05), and only weak correlations between dryness and % active lysozyme (r = 0.3 to 0.5 for all time points). However, stronger correlations were found between active lysozyme and subjective comfort (r = 0.6 to 0.7; p < 0.001). Conclusions.: In addition to investigating total protein deposited on contact lenses, it is of significant clinical relevance to determine the conformational state of the deposited protein. Copyright © 2012 American Academy of Optometry.

2011

Weeks,A., Luensmann,D.,Boone,A, Jones,L., Sheardown,H. Hyaluronic acid as an internal wetting agent in model DMAA/TRIS contact lenses. 2011001-10. [ Show Abstract ]

Model silicone hydrogel contact lenses, comprised of N,N-dimethylacrylamide and methacryloxypropyltris (trimethylsiloxy) silane, were fabricated and hyaluronic acid (HA) was incorporated as an internal wetting agent using a dendrimer-based method. HA and dendrimers were loaded into the silicone hydrogels and cross-linked using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide chemistry. The presence and location of HA in the hydrogels was confirmed using X-ray photoelectron spectroscopy and confocal laser scanning microscopy, respectively. The effects of the presence of HA on the silicone hydrogels on hydrophilicity, swelling behavior, transparency, and lysozyme sorption and denaturation were evaluated. The results showed that HA increased the hydrophilicity and the equilibrium water content of the hydrogels without affecting transparency. HA also significantly decreased the amount of lysozyme sorption (p < 0.002). HA had no effect on lysozyme denaturation in hydrogels containing 0% and 1.7% methacrylic acid (MAA) (by weight) but when the amount of MAA was increased to 5%, the level of lysozyme denaturation was significantly lower compared to control materials. These results suggest that HA has great potential to be used as a wetting agent in silicone hydrogel contact lenses to improve wettability and to decrease lysozyme sorption and denaturation.

Woods,C. A., Dumbleton,K., Jones,L., Fonn,D. Patient use of smartphones to communicate subjective data in clinical trials. Optometry and Vision Science 2011;88,2:290-294. [ Show Abstract ]

Purpose. Various methods have been used in clinical trials to collect time-sensitive subjective responses, including study diaries, telephone interviews, and use of text messaging. However, all of these methods are limited by the uncertainty of when the participants enrolled in the study actually record their responses. This technical note reports on the utility of the BlackBerry smartphone to collect such data and why such a system provides advantages over other methods to report subjective ratings in clinical studies. Methods. The Centre for Contact Lens Research developed an on-line web-enabled system that permits participants to record and immediately transmit subjective rating scores in numerical form directly into a web-enabled database. This, combined with the utility of BlackBerrys, enabled time-specific e-mail requests to be sent to the study participants and then for that data to be simultaneously transmitted to the web-enabled database. This system has been used in several clinical trials conducted at the Centre for Contact Lens Research, in which data were collected at various times and in several specific locations or environments. Results. In the clinical trials conducted using this system, participants provided responses on 97.5% of occasions to the requests for data generated by the automated system. When the request was for data on a set date, this method resulted in responses of 84.1% of the time. Conclusions.The series of clinical trials reported here show the benefits of the utilization of the BlackBerry to collect time- or environment-sensitive data via a web-enabled system. Copyright © 2011 American Academy of Optometry.

Youn,H. -Y, McCanna,D. J., Sivak,J. G., Jones,L. W. In vitro ultraviolet-induced damage in human corneal, lens, and retinal pigment epithelial cells. Molecular Vision 2011;17237-246.

Dumbleton,K. A., Woods,C. A., Jones,L. W., Fonn,D. The relationship between compliance with lens replacement and contact lens-related problems in silicone hydrogel wearers. Contact Lens and Anterior Eye 2011;34,5:216-222. [ Show Abstract ]

To evaluate the relationship between compliance with replacement frequency (RF) and contact lens (CL)-related problems in silicone hydrogel (SiHy) wearers. Methods: 501 SiHy wearers from seven optometry offices completed surveys regarding their lens wear and any CL related problems which they may have experienced in the preceding 12 months. File review was subsequently conducted at their optometry offices to confirm the information provided. Results: 49% of respondents were wearing 2-week replacement (2WR) and 51% 1-month replacement (1MR) SiHy lenses. 67% wore their lenses for longer than the manufacturers' recommended RF (MRRF) and 60% for longer than their optometrist's recommended RF (ORRF). The mean RF was 2.6× the MRRF for 2WR and 1.5× for 1MR wearers (p< 0.001) with median values of 31 and 37 days, respectively. Twenty-three percent reported signs or symptoms consistent with potential complications relating to CL wear. This rate was significantly higher for wearers who were non-compliant with the ORRF than compliant wearers (26% versus 18%, p= 0.028). It was also higher for those multipurpose solution users who reported never/almost never rubbing and rinsing their lenses when compared with those who did this every night (29% versus 17%, p= 0.007). Conclusions: Two thirds of the SiHy wearers did not comply with the MRRF and 2WR wearers stretched the replacement interval of their lenses to a greater degree than 1MR wearers. Failing to replace lenses when recommended and failing to rub and rinse lenses were associated with a higher rate of patient-reported CL problems. © 2011 British Contact Lens Association.

Dumbleton,K. A., Woods,M., Woods,C. A., Jones,L. W., Fonn,D. Ability of patients to recall habitual contact lens products and enhancement of recall using photographic aids. Contact Lens and Anterior Eye 2011;34,5:236-240. [ Show Abstract ]

To determine the proportion of soft contact lens (CL) wearers who are able to recall their habitual products (lenses and care system) correctly from memory, and to evaluate the value of using photographic aids (PAs) to improve recall. Methods: 103 soft lens wearers attended 2 visits to investigate their habitual CL product use. At the first visit they were asked to recall which products they were using and then to identify their products from PAs. They returned for a second visit with their products for confirmation. Results: 51% correctly reported their lens brands from memory alone, which improved to 87% with the use of the PAs (p< 0.001). 41% correctly reported their habitual care system from memory alone, which improved to 80% with the use of PAs (p< 0.001). Females were better at recalling care system brand names than males (49% versus 27% correct, p= 0.040) and wearers with more than 1 year experience with their habitual CLs had better recall than those with up to 1 year experience (63% versus 27%, p= 0.014). Conclusion: Less than 50% of contact lens wearers were able to recall the names of their habitual lens and lens care products correctly from memory. PAs improved this recall significantly for both contact lenses and contact lens care systems. © 2011 British Contact Lens Association.

Gorbet,M. B., Tanti,N. C., Crockett,B., Mansour,L., Jones,L. Effect of contact lens material on cytotoxicity potential of multipurpose solutions using human corneal epithelial cells. Molecular Vision 2011;173458-3467. [ Show Abstract ]

Purpose: Multipurpose solutions (MPS) are used daily to clean and disinfect silicone hydrogel (SiHy) contact lenses. This in vitro study was undertaken to identify the potential for interaction between MPS, SiHy surface treatments, and lens materials, which may lead to changes in the response of human corneal epithelial cells (HCEC) to MPS-soaked lenses. Methods: The MPS tested were renu fresh (formerly known as ReNu MultiPlus; ReNu), OptiFree Express (OFX), OptiFree RepleniSH, SoloCare Aqua, and Complete Moisture Plus. The SiHy materials evaluated were lotrafilcon A, lotrafilcon B, comfilcon A, galyfilcon A, and balafilcon A (BA). MPS-soaked lenses were placed on top of adherent HCEC. The effect of MPS dilutions (0.1 to 10% final concentration in medium) was also characterized. Cell viability, adhesion phenotype and caspase activation were studied after 24-h cell exposure. OFX released from lenses was determined using UV absorbance. Results: A significant reduction in viability (between 30 to 50%) was observed with cells exposed to lenses soaked in ReNu and OFX. A significant downregulation of α3 and β1 integrins, with integrin expression ranging from 60% to 75% of control (cells with no lens), was also observed with OFX and ReNu-soaked lenses. With the exception of BA, all other lenses soaked in OFX resulted in significant caspase activation, whereby over 18% of cells stained positive for caspases. Minimal caspase activation was observed in cells exposed to ReNu and Solo soaked lenses. For both OFX and ReNu, exposing cells to at least a 5% dilution had a significant effect on viability and integrin expression. While Complete and Solo did not lead to reduction in viability, cells exposed to a 10% dilution showed reduced integrin expression down to less than 70% of control value. Comparing cell response to diluted MPS solutions and various MPS-soaked lenses showed that it is not possible to reliably use cell response to MPS dilution alone to assess MPS biocompatibility. Conclusions: Our results demonstrate that the reaction of HCEC to MPS are affected by the type of lenses the MPS is released from and may potentially be influenced by the surface treatment (or lack of it) of SiHy materials. © 2011 Molecular Vision.

Heynen,M., Lorentz,H., Srinivasan,S., Jones,L. Quantification of non-polar lipid deposits on senofilcon A contact lenses. Optometry and Vision Science 2011;88,10:1172-1179.

Kao,E. C. Y., McCanna,D. J., Jones,L. W. Utilization of in vitro methods to determine the biocompatibility of intraocular lens materials. Toxicology in Vitro 2011;25,8:1906-1911.

Keir,N. J., Simpson,T., Hutchings,N., Jones,L., Fonn,D. Outcomes of wavefront-guided laser in situ keratomileusis for hyperopia. Journal of cataract and refractive surgery 2011;37,5:886-893. [ Show Abstract ]

Purpose: To determine the impact of wavefront-guided laser in situ keratomileusis (LASIK) for hyperopia on corrected distance visual acuity (CDVA), contrast sensitivity, and higher-order aberrations (HOAs). Setting: Centre for Contact Lens Research, University of Waterloo, Waterloo, Ontario, Canada. Design: Case series. Methods: This study comprised patients who had LASIK for hyperopia. The HOAs up to the 4th order (5.0 mm pupil) in right eyes were analyzed. Results: The study enrolled 31 patients. The preoperative mean values were sphere, +2.60 diopters (D) ± 1.15 (SD) (range +1.00 to +5.00 D); astigmatism, -0.87 ± 0.74 D (range 0.00 to -3.75 D); and spherical equivalent (SE), +2.16 ± 1.00 D (range +0.63 to +4.50 D). The postoperative refractive SE was within ±0.50 D in 71.0% of eyes. The uncorrected distance visual acuity was 20/20 or better in 87.2% of eyes. There was no significant change in CDVA or contrast sensitivity (all P>.05). There was a significant change in Zernike coefficients Z(0,4), Z(-1,3), Z(-3,3), and Z(3,3) (range of mean absolute change ± SEM: 0.092 ± 0.013 μm to 0.208 ± 0.018 μm; all P<.001). Coefficients Z(-1,3) and Z(3,3) increased and Z(0,4) and Z(-3,3) decreased in magnitude; each had a reversal of sign. The only significant postoperative association was between low-contrast CDVA and Z(0,4) (r = 0.617, P<.001). Conclusions: Low-contrast CDVA after LASIK surgery for hyperopia was correlated with Z(0,4). There were no significant changes in CDVA or contrast sensitivity. The relative risk for losing low-contrast CDVA increased if more than 1 Zernike term had a sign change. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. © 2011 ASCRS and ESCRS.

Lorentz,H., Heynen,M., Kay,L. M. M., Dominici,C. Y., Khan,W., Ng,W. W. S., Jones,L. Contact lens physical properties and lipid deposition in a novel characterized artificial tear solution. Molecular Vision 2011;173392-3405. [ Show Abstract ]

Purpose: To characterize various properties of a physiologically-relevant artificial tear solution (ATS) containing a range of tear film components within a complex salt solution, and to measure contact lens parameters and lipid deposition of a variety of contact lens materials after incubation in this ATS. Methods: A complex ATS was developed that contains a range of salts, proteins, lipids, mucin, and other tear film constituents in tear-film relevant concentrations. This ATS was tested to confirm that its pH, osmolality, surface tension, and homogeneity are similar to human tears and remain so throughout the material incubation process, for up to 4 weeks. To confirm that silicone hydrogel and conventional hydrogel contact lens materials do not alter in physical characteristics beyond what is allowed by the International Organization for Standardization (ISO) 18369-2. The diameter, center thickness, and calculated base curve were measured for five different lens materials directly out of the blister pack, after a rinse in saline and then following a two week incubation in the modified ATS. To test the ATS and the effect of its composition on lipid deposition, two lens materials were incubated in the ATS and a modified version for several time points. Both ATS solutions contained trace amounts of carbon-14 cholesterol and phosphatidylcholine, such that deposition of these specific lipids could be quantified using standard methods. Results: This ATS is a complex mixture that remains stable at physiologically relevant pH (7.3-7.6), osmolality (304- 306 mmol/kg), surface tension (40-46 dynes/cm) and homogeneity over an incubation period of three weeks or more. The physical parameters of the lenses tested showed no changes beyond that allowed by the ISO guidelines. Incubations with the ATS found that balafilcon A lenses deposit significantly more cholesterol and phosphatidylcholine than omafilcon A lenses (p<0.05) and that removing lactoferrin and immunoglobulin G from the ATS can significantly decrease the mass of lipid deposited. Conclusions: This paper describes a novel complex artificial tear solution specially designed for in-vial incubation of contact lens materials. This solution was stable and did not adversely affect the physical parameters of the soft contact lenses incubated within it and showed that lipid deposition was responsive to changes in ATS composition. © 2011 Molecular Vision.

Menzies,K. L., Jones,L. In vitro analysis of the physical properties of contact lens blister pack solutions. Optometry and Vision Science 2011;88,4:493-501. [ Show Abstract ]

Purpose. Since the initial development of silicone hydrogels, many modifications to the bulk and surface properties of the lenses have been undertaken to improve the wettability and comfort of the lenses. Recently, manufacturers have incorporated various "wetting agents" or surface-active agents into the blister packaging solutions (BPSs) of the lenses to improve initial comfort of the lens on eye. The purpose of this study was to measure and compare the pH, surface tension (ST), viscosity, and osmolality of BPSs for a variety of silicone hydrogel and polyHEMA-based hydrogel lenses. In addition, two saline solutions were tested for comparison purposes. Methods. The pH, osmolality, ST, and viscosity were measured for the BPSs for lotrafilcon B and lotrafilcon A and lotrafilcon B with a "modified BPS" (m-lotrafilcon A, m-lotrafilcon B) (CIBA Vision, Duluth, GA); balafilcon A (Bausch & Lomb, Rochester, NY); galyfilcon A, senofilcon A, and narafilcon A (Johnson & Johnson, Jacksonville, FL); and comfilcon A and enfilcon A (CooperVision, Pleasanton, CA) and BPSs from two conventional polyHEMA-based materials-etafilcon A (Johnson & Johnson) and omafilcon A (CooperVision). The two saline solutions tested were Unisol (Alcon, Fort Worth, TX) and Softwear Saline (CIBA Vision). Results. The pH results for the two saline solutions and all BPSs remained in the pH range of tears (6.6-7.8). The ST of the modified BPS was significantly lower (p 0.05) between BPSs made by the same manufacturer but were significantly different compared with BPSs made by different manufacturers (p < 0.05). Conclusions. The incorporation of wetting agents and surfactants into BPSs does alter the physical properties of the BPSs, which may have clinical implications regarding initial in-eye comfort. Copyright © 2011 American Academy of Optometry.

Subbaraman,L. N., Borazjani,R., Zhu,H., Zhao,Z., Jones,L., Willcox,M. D. P. Influence of protein deposition on bacterial adhesion to contact lenses. Optometry and Vision Science 2011;88,8:959-966. [ Show Abstract ]

Purpose. The aim of the study is to determine the adhesion of Gram positive and Gram negative bacteria onto conventional hydrogel (CH) and silicone hydrogel (SH) contact lens materials with and without lysozyme, lactoferrin, and albumin coating. Methods. Four lens types (three SH-balafilcon A, lotrafilcon B, and senofilcon A; one CH-etafilcon A) were coated with lysozyme, lactoferrin, or albumin (uncoated lenses acted as controls) and then incubated in Staphylococcus aureus (Saur 31) or either of two strains of Pseudomonas aeruginosa (Paer 6294 and 6206) for 24 h at 37°C. The total counts of the adhered bacteria were determined using the H-thymidine method and viable counts by counting the number of colony-forming units on agar media. Results. All three strains adhered significantly lower to uncoated etafilcon A lenses compared with uncoated SH lenses (p 0.05). Lactoferrin coating on lenses increased binding (total and viable counts) of Saur 31 (p < 0.05). Lactoferrin-coated lenses showed significantly higher total counts (p < 0.05) but significantly lower viable counts (p < 0.05) of adhered P. aeruginosa strains. There was a significant difference between the total and viable counts (p < 0.05) that were bound to lactoferrin-coated lenses. Albumin coating of lenses increased binding (total and viable counts) of all three strains (p < 0.05). Conclusions. Lysozyme deposited on contact lenses does not possess antibacterial activity against certain bacterial strains, whereas lactoferrin possess an antibacterial effect against strains of P. aeruginosa. © 2011 American Academy of Optometry.

Tanti,N. C., Jones,L., Gorbet,M. B. Impact of multipurpose solutions released from contact lenses on corneal cells. Optometry and Vision Science 2011;88,4:483-492. [ Show Abstract ]

Purpose. To assess, in vitro, the effect of the release of contact lens multipurpose solutions (MPS) from two silicone hydrogel lenses on human corneal epithelial cells. Methods. A monolayer of immortalized human corneal epithelial cells was seeded in a 24-well plate in keratinocyte serum-free medium. Lotrafilcon A (LA) and balafilcon A (BA) lenses were placed on top of the adherent cells for 8 and 24 h, after being soaked in MPS, borate-buffered (Unisol) or phosphate-buffered saline overnight. Cells were assayed for viability using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay or for α3, β1, and β4 integrin expression and caspase activation by flow cytometry. Results. After 8 h, LA lenses soaked in Unisol, Opti-Free Express (OFX), and ReNu MultiPlus (ReNu) showed decrease in cell viability. LA and BA soaked in Complete Moisture Plus (Complete) had similar viability at around 85% of control. After 24 h, a further decrease in viability was observed with all MPS-soaked lenses; LA soaked in OFX significantly reduced viability compared with Unisol-soaked lenses. In addition, reduced levels of integrin expression for lenses soaked in OFX and ReNu, and for BA soaked in Complete were observed. At 24 h, only LA soaked in OFX led to an increase in caspase activation. Conclusions. Our results indicate an increase in cytotoxicity with borate-based MPS solutions in vitro when compared with both phosphate-buffered saline and borate-exposed lenses, suggesting that biocides and/or additives play a role in the observed cell reaction. Moreover, the mechanism of in vitro solution-induced toxicity appeared to be mediated by lens type, suggesting differences in the preferential adsorption/release profile of certain compounds. Copyright © 2011 American Academy of Optometry.

2010

Bitton,E., Jones,L., Simpson,T., Woods,C. Influence of the blink interval on tear meniscus height in soft contact lens and nonlens wearers. Eye and Contact Lens 2010;36,3:156-163. [ Show Abstract ]

Purpose: Tear meniscus height (TMH) is an indirect measurement of tear film volume. This study investigated the temporal changes in the TMH during the blink interval in the morning (8-9 am) and at the end of the day (5-6 pm) in both soft contact lens (CL) and nonlens wearers (NLW). Methods: Fifty participants (25 CL; 25 NLW) were evaluated for their subjective symptoms, TMH, noninvasive break up time, and bulbar hyperemia at the am and pm visits on the same day. The TMH was measured at set intervals between 2 and 15 sec during the blink interval, using an optical coherence tomographer. Results: The NLW group revealed no changes in a variety of symptoms during the day, whereas the CL group reported an increase in dryness (P=0.03) and grittiness (P=0.02) over the day. For both groups, the TMH and calculated tear meniscus volume revealed lower values immediately after the blink and increased progressively afterwards, mainly due to reflex tearing. The am tear meniscus volume values tended to be higher than the pm values for both groups, but this was not significant (NLW P=0.13; CL P=0.82). Noninvasive break up time deteriorated during the day for both groups but was only significant for the CL group (P=0.002), whereas bulbar hyperemia revealed no statistically significant change for either group. Conclusions: Reflex tearing may play a substantial role in the TMH differences observed over the blink interval. Standardization of the time when a TMH measurement is performed will be valuable in comparing tear film clinical studies. Copyright © Contact Lens Association of Ophthalmologists, Inc.

Boone,A., Heynen,M., Joyce,E., Jones,L. Ex vivo protein deposition on bi-weekly silicone hydrogel contact lenses. Optometry and Vision Science 2010;87,2:146.

Caffery,B., Heynen,M. L., Joyce,E., Jones,L., Robert III,R., Senchyna,M. MUC1 expression in Sjogren's syndrome, KCS, and control subjects. Molecular Vision 2010;161720-1727. [ Show Abstract ]

Purpose: To quantify and compare human mucin 1 (MUC1) protein and mRNA expression in tears and conjunctival epithelial cells collected from Sjogren's syndrome (SS), non-Sjogren's keratoconjunctivitus sicca (KCS) and non-dry eyed (NDE) control subjects. Methods: Seventy-six subjects were recruited for this study: 25 SS (confirmed via American-European Consensus Criteria 2002), 25 KCS (confirmed by symptoms and Schirmer scores ≤10 mm) and 26 NDE. Tears were collected using an eyewash technique. Impression cytology was used to gather protein and mRNA from conjunctival epithelial cells. Soluble and membrane bound MUC1 were quantified via western blotting and MUC1 mRNA was quantified by real time qPCR. Results: The SS group demonstrated significantly higher concentrations of soluble MUC1 (0.12±0.11 [SS]; 0.013±0.02 [KCS; p=0.001]; 0.0023±0.0024 [NDE; p<0.001]) and MUC1 mRNA (3.18±1.44 [SS]; 1.79±1.18 [KCS; p<0.05]; 1.60±0.74 [NDE; p<0.05]) compared to both KCS and NDE groups. Soluble MUC1 expression was also higher in the KCS group compared to the NDE group (p=0.02), where as MUC1 mRNA expression was similar in both KCS and NDE groups. Membrane bound MUC1 expression differed only between the SS and NDE groups (0.005±-0.003 [SS]; 0.003±0.002 [NDE; p=0.002]). Conclusions: These results demonstrate that SS subjects express greater quantities of MUC1 protein and mRNA compared to both KCS and control subjects. Increased soluble MUC1 expression was also found in KCS subjects compared to controls. Membrane bound MUC1 was present in higher concentration in SS versus NDE only. These significant changes in MUC1 expression may represent compensatory or protective responses to chronic insult to the ocular surface. © 2010 Molecular Vision.

Dalton,K., Schneider,S., Sorbara,L., Jones,L. Confocal microscopy and optical coherence tomography imaging of hereditary granular dystrophy. Contact Lens and Anterior Eye 2010;33,1:33-40.

Dumbleton,K., Richter,D., Woods,C., Jones,L., Fonn,D. Compliance with contact lens replacement in Canada and the United States. Optometry and Vision Science 2010;87,2:131-139. [ Show Abstract ]

PURPOSE.: To assess eye care practitioners (ECPs) recommendations for replacement frequency (RF) of silicone hydrogel (SH) and daily disposable (DD) lenses in Canada and the U.S. and to compare noncompliance (NC) with manufacturer recommended RF by the ECP and patient, and the reasons given for NC. METHODS.: Invitations to participate were sent by e-mail to ECPs in Canada and the U.S. Twenty patient surveys were sent to 420 ECPs, and 2232 eligible surveys were received from 216 ECPs (26% Canada, 74% U.S.). Questions related to patient demographics, lens type, wearing patterns, ECP instructions for RF, and actual patient RF. ECPs provided lens information and their recommendation for RF after the surveys were completed and sealed in envelopes. Responses were anonymous. RESULTS.: DD accounted for 18% (Canada) vs. 16% (U.S.) of wearers (p > 0.05); 35% (Canada) vs. 45% (U.S.) wore 2-week replacement SH (2WR; p = 0.011); and 47% (Canada) vs. 39% (U.S.) wore 1-month replacement SH (1MR) lenses (p = 0.025). Thirty-four percent (Canada) vs. 18% (U.S.) of ECPs recommended longer RFs than the manufacturer recommended RF for 2WR lens wearers (p 0.05) and were lowest for DD (13% Canada, 12% U.S.), followed by 1MR (33% Canada, 28% U.S.). The highest NC rates were with 2WR (50% Canada, 52% U.S.). The most frequent reason for NC with 2WR and 1MR was 'forgetting which day to replace lenses' (54% Canada, 53% U.S.) and in DD wearers 'to save money' (56% Canada, 29% U.S., p < 0.001). CONCLUSIONS.: 1MR lenses are more frequently prescribed in Canada. ECPs in Canada were NC with 2WR lenses more frequently than U.S. ECPs, but patient NC rates were the same in both countries for all lens types. ECP and patient NC rates were highest for 2WR lens wearers. Copyright © 2010 American Academy of Optometry.

Dumbleton,K., Woods,C., Jones,L., Richter,D., Fonn,D. Comfort and vision with silicone hydrogel lenses: Effect of compliance. Optometry and Vision Science 2010;87,6:421-425. [ Show Abstract ]

PURPOSE. Silicone hydrogel (SH) lenses are usually replaced after 2 weeks (2W) or 1 month (1M); however, many patients do not comply with the manufacturers' recommended replacement frequency (MRRF). The purpose of this analysis was to investigate the effect of compliance with MRRF on comfort and vision in SH wearers. METHODS. As a part of a larger study investigating compliance with MRRF, patients were asked to rate their subjective comfort and vision from 0 (very poor) to 10 (excellent) in the morning, at the end of the day (EVE), when lenses were new, and needed replacing (NR). RESULTS. One thousand three hundred forty-four patients wore 2W replacement modality (2WR) (n = 717) or 1M replacement modality (1MR) (n = 617) SH lenses. Comfort and vision in the morning and when lenses are new were significantly higher than for EVE and NR (p < 0.001). Twenty-nine percent (95% confidence interval 25.3-32.4) of 1MR and 59% (95% confidence interval 55.5-62.7) of 2WR wearers were non-compliant with the MRRF. Compliance had a significant effect on EVE (p = 0.002, p = 0.008) and NR (p < 0.001, p < 0.001) comfort and vision. After accounting for compliance, EVE and NR comfort and EVE vision were higher for 1MR than 2WR (p = 0.015, p = 0.044, p = 0.019). CONCLUSIONS. Compliant patients had better EVE and NR comfort and vision than non-compliant patients, regardless of replacement modality. Optimal subjective performance with SH lenses seems to be facilitated by replacing lenses as recommended. Copyright © 2010 American Academy of Optometry.

Gorbet,M. B., Tanti,N. C., Jones,L., Sheardown,H. Corneal epithelial cell biocompatibility to silicone hydrogel and conventional hydrogel contact lens packaging solutions. Molecular Vision 2010;16272-282. [ Show Abstract ]

Purpose: Although all contact lenses (CLs) are applied initially to the eye directly from a packaging solution, little is known about the effects of these solutions on human corneal epithelial cells (HCECs). Due to the porous nature of CL materials, they have the potential to sorb components of the packaging solution during storage, which could then be subsequently released upon insertion of the CL on the eye. The purpose of this study was to investigate the effect of various packaging solutions on HCECs, using an in vitro model. Methods: An in vitro assay was developed whereby various silicone hydrogels and conventional, poly-2-hydroxyethylmethacrylate (polyHEMA)-based lens materials were removed directly from their packaging and then incubated for up to 24 h with HCECs. The effect of the retained and released packaging solution components on HCECs was assessed by measuring cell viability, adhesion phenotype, and apoptosis. Results: Incubation of HCECs with CLs stored in borate-buffered packaging solutions resulted in a significant reduction in cell viability. Adherent cells incubated with these CLs also exhibited reduced levels of β1 and α3 integrin. Soaking borate-buffered packaged CLs in PBS before cell incubation resolved viability and integrin expression in all cases, with the exception of galyfilcon A and balafilcon A, from which a 20% reduction in cell viability was still observed. In comparison, CLs stored in phosphate-buffered packaging solutions had cellular viability and expression of integrins similar to control cells (cells incubated in the absence of a lens). When incubated with cells at a 10% concentration in serum-free medium, borate-buffered packaging solutions and borate-containing saline (Unisol 4) significantly reduced cell viability and integrin expression. Neither caspase activation nor annexin V binding was observed on cells following exposure to borate buffer solution. However, a significant decrease in reactive oxygen species was observed at 24 h. These latter results suggest that in vitro exposure to low concentration of borate/boric acid results in cell dysfunction, leading to necrosis rather than apoptosis. Conclusions: Borate-buffered packaging solutions were shown to adversely affect the viability and integrin expression of HCECs in vitro. When used in ophthalmic packaging solutions, the antimicrobial properties of borate buffer may be outweighed by its relatively cytotoxic effects on cells. © 2010 Molecular Vision.

Hall,B. J., Jones,L. Contact lens cases: The missing link in contact lens safety?. Eye and Contact Lens 2010;36,2:101-105. [ Show Abstract ]

Purpose: To summarize a variety of issues associated with contact lens case contamination and discuss appropriate methods that can limit this. Methods: A literature review was undertaken investigating the major factors associated with case contamination, with specific reference to the major pathogens associated with contamination, the role of bacterial biofilms, and methods that can limit contamination. Results: The use of antimicrobial cases, regular case cleaning and case replacement, avoidance of topping up solutions, and not using tap water to rinse cases all appear to be important in avoidance of significant case contamination. Conclusions: Contact lens case contamination is a significant public health concern and may contribute significantly to the development of microbial keratitis in contact lens wearers. Patients should be reminded that they must clean and disinfect their lens cases daily, should avoid the use of tap water for rinsing them, must not top up their solutions, must take into careful consideration where and how the cases are stored during the time that lenses are being worn and that they must be replaced regularly. The adoption of these methods will substantially reduce the levels of contamination of cases with pathogenic microbes. © 2010 Lippincott Williams & Wilkins.

Keech,A., Simpson,T., Jones,L. Repeatability of pachymetry and thinnest point localization using a Fourier-domain optical coherence tomographer. Optometry and Vision Science 2010;87,10:736-741.

Keir,N., Woods,C. A., Dumbleton,K., Jones,L. Clinical performance of different care systems with silicone hydrogel contact lenses. Contact Lens and Anterior Eye 2010;33,4:189-195.

Luensmann,D., Heynen,M., Liu,L., Sheardown,H., Jones,L. The efficiency of contact lens care regimens on protein removal from hydrogel and silicone hydrogel lenses. Molecular Vision 2010;16,10-11:79-92. [ Show Abstract ]

Purpose: To investigate the efficiency of lysozyme and albumin removal from silicone hydrogel and conventional contact lenses, using a polyhexamethylene biguanide multipurpose solution (MPS) in a soaking or rubbing/soaking application and a hydrogen peroxide system (H2O2). Methods: Etafilcon A, lotrafilcon B and balafilcon A materials were incubated in protein solutions for up to 14 days. Lenses were either placed in radiolabeled protein to quantify the amount deposited or in fluorescent-conjugated protein to identify its location, using confocal laser scanning microscopy (CLSM). Lenses were either rinsed with PBS or soaked overnight in H2O2 or MPS with and without lens rubbing. Results: After 14 days lysozyme was highest on etafilcon A (2,200 μg) >balafilcon A (50 μg) >lotrafilcon B (9.7 μg) and albumin was highest on balafilcon A (1.9 μg) =lotrafilcon B (1.8 μg) >etafilcon A (0.2 μg). Lysozyme removal was greatest for balafilcon A >etafilcon A >lotrafilcon B, with etafilcon A showing the most change in protein distribution. Albumin removal was highest from etafilcon A >balafilcon A >lotrafilcon B. H2O2 exhibited greater lysozyme removal from etafilcon A compared to both MPS procedures (p0.62). Albumin removal was solely material specific, while all care regimens performed to a similar degree (p>0.69). Conclusions: Protein removal efficiency for the regimens evaluated depended on the lens material and protein type. Overall, lens rubbing with MPS before soaking did not reduce the protein content on the lenses compared to nonrubbed lenses (p=0.89). © 2010 Molecular Vision.

Luensmann,D., Jones,L. Impact of fluorescent probes on albumin sorption profiles to ophthalmic biomaterials. Journal of Biomedical Materials Research - Part B Applied Biomaterials 2010;94,2:327-336.

Menzies,K. L., Jones,L. The impact of contact angle on the biocompatibility of biomaterials. Optometry and Vision Science 2010;87,6:387-399. [ Show Abstract ]

Biomaterials may be defined as artificial materials that can mimic, store, or come into close contact with living biological cells or fluids and are becoming increasingly popular in the medical, biomedical, optometric, dental, and pharmaceutical industries. Within the ophthalmic industry, the best example of a biomaterial is a contact lens, which is worn by ∼125 million people worldwide. For biomaterials to be biocompatible, they cannot illicit any type of unfavorable response when exposed to the tissue they contact. A characteristic that significantly influences this response is that related to surface wettability, which is often determined by measuring the contact angle of the material. This article reviews the impact of contact angle on the biocompatibility of tissue engineering substrates, blood-contacting devices, dental implants, intraocular lenses, and contact lens materials. Copyright © 2010 American Academy of Optometry.

Menzies,K. L., Rogers,R., Jones,L. In vitro contact angle analysis and physical properties of blister pack solutions of daily disposable contact lenses. Eye and Contact Lens 2010;36,1:10-18. [ Show Abstract ]

Objective: The purpose of this study was to measure the advancing and receding contact angles (CAs) of five daily disposable (DD) lenses and the osmolality, surface tension (ST), and pH of each blister pack solution. Methods: The advancing and receding CAs were measured directly out of the blister pack for five DD lenses: omafilcon A (CooperVision), nelfilcon A (CIBA Vision), modified nelfilcon A (CIBA Vision), etafilcon A (Johnson & Johnson), and narafilcon A (Johnson & Johnson). Advancing CAs were measured using sessile drop and Wilhelmy balance methods. Receding CAs were measured using the Wilhelmy balance method. ST, pH, and osmolality were measured for each blister pack solution from all the DD lenses. Results: The advancing CAs for the nelfilcon A lenses were statistically lower (P<0.05) than the advancing CAs of the other three lenses. The receding CAs for etafilcon A were statistically lower (P<0.05) than the receding CAs for the other four lenses. The pH of all the blister pack solutions was relatively neutral (7.01-7.43). The ST of the blister pack solution for the modified nelfilcon A was significantly lower (P<0.05) than the ST of all other blister pack solutions. The osmolality of the blister pack solutions for the etafilcon A and narafilcon A lenses were significantly higher (P<0.05) than the other blister pack solutions. Conclusions: The modified nelfilcon A lens had low advancing CAs and low receding CAs showing minimal hysteresis. The blister pack solution for the modified nelfilcon A lens had the lowest ST, a low osmolality, and a neutral pH. Copyright © Contact Lens Association of Ophthalmologists, Inc.

Papas,E., Wolffsohn,J. S., Jones,L. Innovation in contact lenses: Basic research and clinical science. Journal of Optometry 2010;3,3:123-124.

Peterson,R. C., Fonn,D., Woods,C. A., Jones,L. Impact of a rub and rinse on solution-induced corneal staining. Optometry and Vision Science 2010;87,12:1030-1036. [ Show Abstract ]

Purpose.: To investigate whether the inclusion of a rub and rinse step before contact lens disinfection has an impact on solution-induced corneal staining. Methods.: This was a prospective, double-masked, single investigator study. Twenty participants were recruited for two visits, where balafilcon-A lenses were worn bilaterally for 2 h. Each pair of lenses was prepared using two different methodologies. The "control" lens was transferred from the blister pack directly into a storage case containing polyhexamethylene biguanide-based lens care solution. The contralateral "test" lens was rubbed and simultaneously rinsed using the same polyhexamethylene biguanide-based care solution, for either 60 s (visit 1) or 20 s (visit 2). Both lenses were then soaked in the solution overnight. After baseline corneal staining assessments, the lenses were inserted following a randomized contralateral model. After 2 h, lenses were removed, corneal staining was regraded, and comfort scores were obtained. Results.: Rubbed and rinsed test lenses induced significantly less corneal staining than control lenses for all participants during visit 1 (mean ± SD: 516 ± 843 vs. 2170 ± 902; p 0.05). Conclusions.: Corneal staining induced after 2 h of lens wear with the combination of balafilcon-A and polyhexamethylene biguanide-based lens care solution can be significantly reduced by including a rub and rinse step before overnight soaking. Further work is required to establish the longevity of this effect during the monthly wearing cycle. Copyright © 2010 American Academy of Optometry.

Situ,P., Simpson,T. L., Jones,L. W., Fonn,D. Effects of silicone hydrogel contact lens wear on ocular surface sensitivity to tactile, pneumatic mechanical, and chemical stimulation. Investigative Ophthalmology and Visual Science 2010;51,12:6111-6117. [ Show Abstract ]

PURPOSE. To determine the effects of silicone hydrogel lens wear and lens-solution interactions on ocular surface sensitivity. METHODS. Forty-eight adapted lens wearers completed the study, which comprised two phases. Phase 1 included habitual lens wear, no lens wear (7 ± 3 days), and balafilcon A lenses (PV; PureVision; Bausch & Lomb, Rochester, NY) with a hydrogen peroxide-based regimen for 2 weeks; phase 2 included wear of PV with the use of a multipurpose solution containing either polyhexamethylene-biguanide (PHMB) or Polyquad/Aldox (Alcon Laboratories, Fort Worth, TX) preservative, each for 1 week, with a 2-week washout period between solutions. Tactile and pneumatic (mechanical and chemical) stimuli were delivered, and thresholds were determined by Cochet-Bonnet (Luneau Ophthalmologie, Chartres, France) and Belmonte (Cooperative Research Centre for Eye Research and Technology, Sydney, NSW, Australia) pneumatic esthesiometers, respectively. Corneal and conjunctival thresholds and staining scores were assessed at baseline, after 2 and 8 hours of lens wear on day 1 and at the end of each wearing cycle (2 hours). RESULTS. In phase 1, compared to the no-lens baseline, corneal tactile thresholds increased at the 1-day, 8-hour and the 2-week visits (P < 0.05), whereas conjunctival mechanical thresholds decreased at the 1-day, 2-hour and the 2-week visits (P < 0.05). In phase 2, the chemical thresholds were lower with PHMBpreserved solution compared with the Polyquad/Aldox system at the 1-day, 2-hour and the 1-week visits (P < 0.05). Staining scores correlated inversely with conjunctival chemical thresholds (all P < 0.05). CONCLUSIONS. Ocular surface sensitivity changed in adapted lens wearers, when lenses were refit after a no-lens interval and during lens wear with different care regimens. The corneal staining that was observed with certain lens-solution combinations was accompanied by sensory alteration of the ocular surface-that is, higher levels of staining correlated with increased conjunctival chemical sensitivity. © Association for Research in Vision and Ophthalmology.

Srinivasan,S., Joyce,E., Boone,A., Simpson,T., Jones,L., Senchyna,M. Tear lipocalin and lysozyme concentrations in postmenopausal women. Ophthalmic and Physiological Optics 2010;30,3:257-266.

Subbaraman,L. N., Jones,L. Kinetics of lysozyme activity recovered from conventional and silicone hydrogel contact lens materials. Journal of Biomaterials Science, Polymer Edition 2010;21,3:343-358.

2009

Boone,A., Heynen,M., Joyce,E., Varikooty,J., Jones,L. Ex vivo protein deposition on bi-weekly silicone hydrogel contact lenses. Optometry and Vision Science 2009;86,11:1241-1249. [ Show Abstract ]

Purpose. This study investigated the protein deposition that occurs on daily wear silicone hydrogel (SH) lenses, after 2 weeks of wear. Methods. A total of 40 subjects were divided into equal groups, based on their habitual SH contact lens [CIBA Vision O2OPTIX (O2); Johnson & Johnson ACUVUE ADVANCE with HYDRACLEAR (ADV); Bausch & Lomb PureVision (PV); CIBA Vision Night & Day (ND)]. A randomized, double-masked, cross-over study was conducted in which subjects wore either their habitual SH material or Johnson & Johnson ACUVUE OASYS with HYDRACLEAR PLUS (OAS) for 2 weeks. At the end of the 2-week period, lenses were collected for analysis of total protein, total lysozyme, and percent denatured lysozyme. Results. Total protein was greatest for PV (33 ± 6 μg/lens), with other lenses depositing 0.05). Total lysozyme was also greatest for the PV lens (11 ± 3 μg/lens), with other lenses depositing 0.05). Total lysozyme was also greatest for the PV lens (11 ± 3 μg/lens), with other lenses depositing 0.05). Total lysozyme was also greatest for the PV lens (11 ± 3 μg/lens), with other lenses depositing 0.05). The percentage of lysozyme that was denatured was greatest for ND (90 ± 8%) and lowest for PV (23 ± 10%). The lysozyme extracted from ND and O2 lenses was significantly more denatured than that extracted from the other lens materials (p 0.05) or between ADV, OAS, and PV (p > 0.05). The amount of denatured lysozyme/lens was <3 μg/lens for all materials. Lysozyme as a percentage of the total protein deposited ranged from 32 (PV) to 6% (O2). Conclusions. This study confirms that all SH lenses deposit low levels of protein, and that the amount and percentage of denatured lysozyme can vary, depending on the overall surface charge of the material and absence or type of surface treatment. © 2009 American Academy of Optometry.

Boone,A., Hui,A., Jones,L. Uptake and release of dexamethasone phosphate from silicone hydrogel and FDA group I, II, and IV hydrogel contact lenses. Eye and Contact Lens 2009;35,5:260-267. [ Show Abstract ]

OBJECTIVES: To investigate the uptake and release kinetics of the synthetic glucocorticoid anti-inflammatory drug dexamethasone into various conventional and silicone hydrogel contact lens materials. METHODS: Three conventional and six silicone hydrogel lenses were used in this study. A 0.1% dexamethasone solution was formulated and used to dope the various contact lens materials. The uptake and release of the drug was measured using a UV-visible light spectrophotometer at various time points during a period of 24 hr for each phase. RESULTS: Statistical analysis showed that all lenses took up a significant amount of dexamethasone. Alphafilcon A and lotrafilcon A showed the greatest uptake of dexamethasone, at 118 +/- 10 microg/lens and 102 +/- 11 microg/lens, respectively, and galyfilcon took up the least amount of drug at 34 +/- 6 microg/lens. The release of the drug from the lens materials was also statistically significant. The majority of the lenses released between 20 and 30 microg/lens, except for alphafilcon A and lotrafilcon A, which released a statistically different amount of drug when compared with the other lens materials. Alphafilcon A released 65 +/- 1.3 microg/lens, whereas lotrafilcon A slowly released only 11 +/- 0.2 microg/lens. CONCLUSIONS: Although most of the lenses released enough drug to have anti-inflammatory action, none of the materials released drug for a long enough period of time to be clinically useful as a drug delivery device.

Chow,L. M., Subbaraman,L. N., Sheardown,H., Jones,L. Kinetics of in vitro lactoferrin deposition on silicone hydrogel and FDA group II and group IV hydrogel contact lens materials. Journal of Biomaterials Science, Polymer Edition 2009;20,1:71-82. [ Show Abstract ]

The aim of this study was to compare the kinetics of lactoferrin deposition on silicone hydrogel (SH) and conventional FDA group II and group IV hydrogel contact lens materials. Seven lens materials, two conventional (etafilcon A, FDA group IV; omafilcon A, FDA group II) and five SH (lotrafilcon A, lotrafilcon B, balafilcon A, galyfilcon A and senofilcon A), were incubated in 1 ml (125)I-labeled lactoferrin solution for time periods ranging from 1 h to 28 days. At the end of specified incubation periods radioactive counts were determined on the lenses using an Automatic Gamma Counter. There was a gradual increase in lactoferrin deposition on all the lenses across all time points. At the end of 28 days the amount of lactoferrin/lens in microg was 11.3 +/- 1.9 for etafilcon A, 6.8 +/- 2.0 for omafilcon A, 2.1 +/- 0.9 for lotrafilcon A, 3.1 +/- 1.0 for lotrafilcon B, 11.8 +/- 2.9 for balafilcon A, 5.4 +/- 1.1 for galyfilcon A and 5.6 +/- 0.6 for senofilcon A. After 28 days, etafilcon A and balafilcon A deposited lactoferrin to the greatest degree (P < 0.05), but these were not different from each other (P = 0.48), while lotrafilcon A and B deposited the least (P < 0.05 vs. other lenses; P = 0.57 with each other). Galyfilcon A, senofilcon A and omafilcon A (P < 0.05 compared with other lenses; P > 0.05 with each other) deposited intermediate levels of lactoferrin. We concluded that radiochemical analysis is a sensitive and effective technique to determine the small quantities of lactoferrin deposited on SH lenses. The kinetics of lactoferrin deposition on contact lens materials depend on the chemical structure of the lens material.

Dumbleton,K., Woods,C., Jones,L., Fonn,D., Sarwer,D. B. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement in the United States. Eye and Contact Lens 2009;35,4:164-171. [ Show Abstract ]

OBJECTIVE: The objectives of this study were to assess current recommendations for replacement frequency (RF) of silicone hydrogel (SH) and daily disposable (DD) lenses, to determine compliance with these recommendations, and to investigate the reasons given for noncompliance. METHODS: A package containing 20 patient surveys was sent to 309 eye care practitioners (ECPs) in the United States who had agreed to participate in the study. One thousand eight hundred fifty-nine completed surveys were received from 158 ECPs and 1,654 surveys were eligible for analysis. Questions related to patient demographics, lens type, lens wearing patterns, the ECP instructions for RF, and the actual patient reported RF. ECPs were asked to provide lens information and their recommendation for RF after the surveys had been completed and sealed in envelopes. All responses were anonymous. RESULTS: Sixty-six percent of patients were women and their mean age was 34 ± 12 years. Eighty-eight percent of lenses were worn for daily wear, 12.8 ± 3.2 hours a day, 6.2 ± 1.5 days a week. Lens type distribution was 16% DD, 45% 2 week (2W) SH, and 39% 1 month (1M) SH. ECP recommendations for RF varied according to the lens type; 1% of 1M (95% CI 0.2-1.7), 4% of DD (95% CI 2.1-7.2), and 18% of 2W (95% CI 15.1-20.7) patients were given instructions that did not conform to the manufacturers' recommended RF (MRRF). When considering only those patients who were given the correct instructions for RF, 38% were not compliant with the MRRF; noncompliance rates varied according to the lens type and were 12% for DD (95% CI 8.6-17.2), 28% for 1M (95% CI 24.9-32.1), and 52% for 2W (95% CI 47.8-55.8). The most frequent reasons for over wearing lenses were "forgetting which day to replace lenses" (51%) and "to save money" (26%). Fifty-three percent believed that a reminder system would aid compliance; the most popular methods being a cell phone reminder or text message (29%) and a nominated day each week or month (26%). Discussions between the ECPs and the patients were more extensive for patients who were compliant with the MRRF. CONCLUSIONS: ECPs recommended RFs more frequently with DD and 1M SH lenses than with 2W SH lenses, consistent with manufacturers' recommendations. Patients were less compliant with RF than ECPs for all lens types investigated. Patients were most compliant with RF when wearing DD lenses and least compliant when wearing 2W SH lenses. Better communication facilitated greater compliance with RF. More than half of those not replacing lenses, when recommended, reported that this was because they forgot which day to replace their lenses. © 2009 Lippincott Williams & Wilkins, Inc.

Keech,A., Flanagan,J., Simpson,T., Jones,L. Tear meniscus height determination using the OCT2 and the RTVue-100. Optometry and Vision Science 2009;86,10:1154-1159. [ Show Abstract ]

PURPOSE: To compare anterior segment spectral-domain optical coherence tomography (SOCT) tear meniscus height (TMH) measures with those from the more commonly used time-domain OCT (TOCT). METHODS: The right eye of 50 healthy subjects had images of their TMH captured with TOCT (OCT2) and SOCT (RTVue-100). Data were acquired using two different anterior segment lenses, the cornea/anterior module-short (CAM-S) and long (CAM-L), on the SOCT. Images were then analyzed for differences in their derived TMH. RESULTS: The average TMH for TOCT was 0.280 ± 0.139 mm, whereas the mean TMH measured using the SOCT was 0.354 ± 0.163 mm and 0.345 ± 0.167 mm for the CAM-S and CAM-L, respectively. There was a significant difference (p < 0.001) when comparing TOCT with either of the SOCT lenses. There was no statistically significant difference between the CAM-L and CAM-S (p = 1.0). Bland-Altman analysis showed poor agreement between TOCT and SOCT (95% limits of agreement -0.138 to + 0.285 mm for the CAM-S and -0.185 to +0.315 mm for the CAM-L). CONCLUSIONS: The RTVue-100 produces TMH measurements that are significantly higher than OCT2 in a normal patient population. However, the RTVue-100 showed a number of other advantages over the OCT2 in the measurement and analysis of images. Future work needs to determine the causative factors behind the observed differences.

Keir,N. J., Simpson,T., Jones,L. W., Fonn,D. Wavefront-guided LASIK for myopia: Effect on visual acuity, contrast sensitivity, and higher order aberrations. Journal of Refractive Surgery 2009;25,6:524-533. [ Show Abstract ]

PURPOSE: To determine the impact of wavefrontguided LASIK for myopia with or without astigmatism on high and low contrast best spectacle-corrected visual acuity (BSCVA), photopic and mesopic contrast sensitivity, and higher order aberrations. METHODS: Bilateral wavefront-guided LASIK (LADARVision4000; Hansatome microkeratome) was performed on 324 eyes (162 patients) with a mean spherical manifest refraction of -2.84±1.35 diopters (D) (range: -0.25 to -6.50 D) and astigmatism of -0.81±0.74 D (range: 0 to -4.00 D). Mean age was 37.7±9.3 years (range: 20 to 60 years). Best spectacle-corrected visual acuity and contrast sensitivity were assessed using ETDRS charts and vertical sinusoidal gratings, respectively. Higher order aberrations were measured using a Shack-Hartmann wavefront sensor, analyzed across a 5-mm pupil. Repeated measures and post hoc analyses determined statistical significance (P<.0025). Only right eyes were analyzed. RESULTS: One hundred thirty-six eyes (84%) had uncorrected visual acuity of 20/20 or better 6 months postoperative; 80.9% (131 eyes) were within ±0.50 D of attempted correction. Statistically significant postoperative improvements were noted in high and low contrast BSCVA (both P≤.001); in photopic contrast sensitivity at 3, 6, and 12 cycles per degree (cpd); and in mesopic contrast sensitivity at 12 and 18 cpd (all P<.001). With respect to higher order aberrations, a statistically significant change was seen in Zernike coefficients Z 3 -1, Z 3 1, Z 3 -3, Z 3 3, and Z 3 4 following surgery (range of mean absolute change: 0.042 to 0.142 μm; all P<.001). All increased in magnitude except for Z 3 -3, which decreased. CONCLUSIONS: Despite an increase in higher order aberrations, wavefront-guided LASIK yields excellent visual acuity and contrast sensitivity. Spherical aberration, which increases the most following non-wavefront-guided LASIK, showed no significant change.

Luensmann,D., Heynen,M., Liu,L., Sheardown,H., Jones,L. Determination of albumin sorption to intraocular lenses by radiolabeling and confocal laser scanning microscopy. Journal of cataract and refractive surgery 2009;35,11:2000-2007. [ Show Abstract ]

Purpose: To determine albumin adsorption profiles and penetration depth of 3 intraocular lens (IOL) materials over time using confocal laser scanning microscopy (CLSM) and radiolabeling. Setting: Centre for Contact Lens Research, School of Optometry, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada. Methods: Poly(methyl methacrylate) (PMMA), silicone, and foldable hydrophilic acrylic IOLs were incubated in 0.5 mg/mL bovine serum albumin (BSA) for 1, 7, and 14 days. The BSA was conjugated with lucifer yellow VS to allow identification of the protein location by fluorescent imaging with CLSM. Next, the protein uptake was quantified using 2% 125I-labeled BSA. Results: Confocal laser scanning microscopy showed increasing BSA uptake for silicone and PMMA IOLs after 14 days of incubation (P<.05), with an apparent penetration depth of 8.7 μm ± 1.9 (SD) and 9.2 ± 1.4 μm, respectively. For hydrophilic acrylic IOLs, BSA was detected at a depth of 38 ± 7.4 μm after 1 day, followed by an increase to 192.7 ± 16.2 μm after 14 days. Despite the penetration depth into the hydrophilic acrylic IOLs, quantitative results confirmed that PMMA and hydrophilic acrylic deposited significantly less BSA (mean 278.3 ± 41.7 ng and 296.5 ± 33.1 ng, respectively) than silicone IOLs (mean 392.6 ± 37.6 ng) (P<.05). Conclusions: Silicone and PMMA IOL materials showed BSA sorption near the lens surface only, while BSA penetrated deep into the hydrophilic acrylic IOL matrix. Combining the qualitative CLSM method and quantitative radiolabeling technique provided detailed information on protein interactions with implantable biomaterials. © 2009 ASCRS and ESCRS.

Luensmann,D., Zhang,F., Subbaraman,L., Sheardown,H., Jones,L. Localization of lysozyme sorption to conventional and silicone hydrogel contact lenses using confocal microscopy. Current eye research 2009;34,8:683-697. [ Show Abstract ]

PURPOSE: To investigate the distribution profile of hen egg lysozyme (HEL) through poly-2-hydroxyethyl methacrylate (pHEMA)-based lens materials and silicone hydrogel (SH) lens materials using confocal laser scanning microscopy (CLSM). METHODS: Five silicone SH materials (balafilcon A, lotrafilcon A, lotrafilcon B, galyfilcon A, senofilcon A) and four pHEMA-based materials (alphafilcon A, etafilcon A, omafilcon A, vifilcon A) were incubated in 1.9 mg/ml protein solution for 24 hours. The protein solution consisted of HEL, which was conjugated with either fluorescein isothiocyanate (FITC) or lucifer yellow VS dilithium salt (LY). CLSM (Zeiss LSM 510 META) identified the location of the fluorescently labeled protein by using 1 micro m depth scans through the lens. In a second experiment, lenses were incubated with 2% (125) I labeled HEL to determine the amount of deposited protein on each lens. Both techniques were combined to describe the individual HEL profiles. RESULTS: After the incubation in fluorescently labeled HEL, all pHEMA-based materials and the SH material balafilcon A accumulated protein throughout the entire lens material, while, for the SH lenses lotrafilcon A and lotrafilcon B, HEL was primarily detected on the lens surface alone. Differences in protein uptake pattern due solely to the two conjugated dyes were most apparent for the SH materials galyfilcon A and senofilcon A; HEL was detected throughout these lenses when conjugated with LY but accumulated primarily on the surface when conjugated with FITC. CONCLUSION: CLSM in combination with a radiolabel technique can describe both the location and degree of protein deposition on different contact lens materials.

Ngo,W., Heynen,M., Joyce,E., Jones,L. Impact of protein and lipid on neutralization times of hydrogen peroxide care regimens. Eye and Contact Lens 2009;35,6:282-286. [ Show Abstract ]

Purpose: To investigate the effect of protein, lipid, and lens material on the neutralization kinetics of one-step hydrogen peroxide disinfection systems. Methods: A UV-based assay was used to determine the rate of neutralization of three one-step hydrogen peroxide systems (CIBA Vision Clear Care; CIBA Vision AOSEPT; Abbott Medical Optics UltraCare). Protein (bovine serum albumin and lysozyme) and various lipids were added to the lens cases during the neutralization phase to determine whether they influenced the rate of neutralization. Finally, rates were determined when the cases contained a silicone hydrogel lens material (lotrafilcon A) or Food and Drug Administration group IV (etafilcon A) lenses. Results: Neutralization for all three systems was complete within 90 minutes. The rate of neutralization for Clear Care and AOSEPT were not significantly different from each other (P=NS). UltraCare exhibited statistically higher levels of peroxide up to the 20-minute time point (P<0.001) Protein, lipid, or lens material did not significantly affect the rate of neutralization for any regimen (P=NS). Conclusions: Tablet-based one-step disinfection systems neutralize at a slower rate than disc-based peroxide systems, but this difference is only significant during the first 20 minutes after the onset of neutralization. Neither lens deposition nor lens material plays a role in the speed of neutralization of peroxide-based systems. © 2009 Lippincott Williams & Wilkins.

Sorbara,L., Jones,L., Williams-Lyn,D. Contact lens induced papillary conjunctivitis with silicone hydrogel lenses. Contact Lens and Anterior Eye 2009;32,2:93-96. [ Show Abstract ]

PURPOSE: To describe the refitting of a soft lens wearer into a silicone hydrogel lens due to neovascularization. This change, in turn, caused contact lens induced papillary conjunctivitis (CLPC) and a further refitting was necessary. METHODS: The patient was refit into a high Dk surface treated silicone hydrogel with a high modulus value. A second refitting was undertaken into a lower Dk silicone hydrogel contact lens with a lower modulus value which had no surface treatment but incorporated an internal wetting agent. RESULTS: A high Dk/t lens was used to resolve existing neovascularization and chronic hyperaemia. Subsequently, CLPC response occurred, possibly due to a combination of factors, resulting in irritation of the palpebral conjunctiva. This resulted in temporary lens discontinuation. A second silicone hydrogel lens was fit, along with the use of a non-preserved care system, which led to improvement and eventual resolution of the condition. CONCLUSION: High Dk silicone hydrogel lenses have shown excellent efficacy in resolving hypoxic complications such as neovascularization and hyperaemia. However, attention needs to be paid to their potential effect on the upper tarsal plate. More than one silicone hydrogel lens may be needed to help resolve these issues.

Subbaraman,L. N., Glasier,M. A., Sheardown,H., Jones,L. Efficacy of an extraction solvent used to quantify albumin deposition on hydrogel contact lens materials. Eye and Contact Lens 2009;35,2:76-80. [ Show Abstract ]

OBJECTIVES: Extracting proteins from conventional hydrogel (CH) and silicone hydrogel (SH) contact lens materials using a mixture of trifluoroacetic acid/acetonitrile (TFA/ACN) is a well-established procedure for quantifying individual and total protein deposited on contact lenses. The purpose of this study was to determine the efficacy of TFA/ACN in extracting albumin from SH and a CH group IV lens material using an in vitro model. METHODS: One CH group IV lens material (etafilcon A) and five different SH lens materials (lotrafilcon A, lotrafilcon B, balafilcon A, galyfilcon A, and senofilcon A) were incubated in both simple albumin solution and a complex artificial tear protein solution containing 125I-labeled albumin. All the lens materials were incubated for 14 days at 37 degrees C with constant rotations. Following the incubation period, radioactive counts were determined and the lenses were placed in an appropriate volume of the extraction solvent. After the specified time, the lenses were removed and radioactive counts were determined again to calculate the amount of albumin remaining on the lenses post-extraction. RESULTS: Extraction efficiencies for albumin from the artificial tear protein solution were 97.2% +/- 2 for etafilcon A, 77.3% +/- 6.2 for lotrafilcon A, 73.5% +/- 5.6 for lotrafilcon B, 81.5% +/- 5.8 for balafilcon, 91.2% +/- 3.4 for galyfilcon A, and 89.2% +/- 3.4 for senofilcon A. Results were similar for the albumin extracted after incubating in the simple albumin solution. CONCLUSIONS: Although TFA/ACN is efficient at extracting albumin deposited on etafilcon lenses, it does not extract all the albumin that is deposited on SH lenses and alternative extraction procedures should be sought.

Subbaraman,L. N., Woods,J., Teichroeb,J. H., Jones,L. Protein deposition on a lathe-cut silicone hydrogel contact lens material. Optometry and Vision Science 2009;86,3:244-250. [ Show Abstract ]

PURPOSE: To determine the quantity of total protein, total lysozyme, and the conformational state of lysozyme deposited on a novel, lathe-cut silicone hydrogel (SiHy) contact lens material (sifilcon A) after 3 months of wear. METHODS: Twenty-four subjects completed a prospective, bilateral, daily-wear, 9-month clinical evaluation in which the subjects were fitted with a novel, custom-made, lathe-cut SiHy lens material. The lenses were worn for three consecutive 3-month periods, with lenses being replaced after each period of wear. After 3 months of wear, the lenses from the left eye were collected and assessed for protein analysis. The total protein deposited on the lenses was determined by a modified Bradford assay, total lysozyme using Western blotting and the lysozyme activity was determined using a modified micrococcal assay. RESULTS: The total protein recovered from the custom-made lenses was 5.3 +/- 2.3 microg/lens and the total lysozyme was 2.4 +/- 1.2 microg/lens. The denatured lysozyme found on the lenses was 1.9 +/- 1.0 microg/lens and the percentage of lysozyme denatured was 80 +/- 10%. CONCLUSIONS: Even after 3 months of wear, the quantity of protein and the conformational state of lysozyme deposited on these novel lens materials was very similar to that found on similar surface-coated SiHy lenses after 2 to 4 weeks of wear. These results indicate that extended use of the sifilcon A material is not deleterious in terms of the quantity and quality of protein deposited on the lens.

2008

Bitton,E., Keech,A., Jones,L., Simpson,T. Subjective and objective variation of the tear film pre- and post-sleep. Optometry and Vision Science 2008;85,8:740-749. [ Show Abstract ]

PURPOSE: To date, few studies have correlated the overnight effects of the preocular tear film (POTF) with subjective symptoms. This study investigates the POTF volume and stability, bulbar hyperemia (BH), tear ferning (TF) and the participant's subjective symptoms, pre- and post-sleep. METHODS: Thirty subjects were recruited, consisting of two evenly distributed groups who were symptomatic of dry eye (DE) and those that were asymptomatic dry eye, determined using the McMonnies questionnaire. Subjects were evaluated at 10 p.m. (baseline), on waking at 7 a.m., and then hourly until 10 a.m. At each visit, tear meniscus height (TMH), various subjective factors, BH and POTF stability by non-invasive break-up time (NIBUT) were assessed. Tear collection was performed at 10 p.m, 7 and 10 a.m. for TF analysis. RESULTS: With the exception of burning, all other symptoms (comfort, dryness, clarity of vision, and grittiness) revealed an overnight change (p < 0.05) within each group, but not between the two groups (p > 0.05). Both the tear meniscus height and BH were elevated upon waking and differed significantly between test times for each group (p < 0.05), but not between groups (p > 0.05). NIBUT was lower for the DE group (p < 0.001). The non-dry eye (NDE) group did not significantly alter over time (p > 0.05), but the DE group did (p = 0.004), with a longer NIBUT in the morning. TF demonstrated a degraded pattern upon waking for both groups (p < 0.05). Most of the changes returned to baseline within an hour after waking. CONCLUSIONS: The properties of the POTF undergo a change during extended periods of eye closure and the human POTF is different upon waking to that present immediately before sleep. Most of the parameters determined rapidly revert to baseline levels once the POTF is allowed to refresh.

Caffery,B., Joyce,E., Boone,A., Slomovic,A., Simpson,T., Jones,L., Senchyna,M. Tear lipocalin and lysozyme in sjögren and non-sjogren dry eye. Optometry and Vision Science 2008;85,8:661-667. [ Show Abstract ]

PURPOSE.: To evaluate the concentration of tear lipocalin, lysozyme, and total protein in Sjogrens Syndrome (SS), non-Sjogrens keratoconjunctivitis sicca (KCS), and non-dry-eyed (NDE) individuals. METHODS.: Seventy-six subjects were recruited for this study: 25 SS subjects; 25 KCS subjects, and 26 NDE individuals. Symptoms were measured with a visual analogue scale. Tear flow was measured by the Schirmer I test without anesthesia. Tears were collected using an eye wash technique. Total tear protein was quantified using the DC Protein Assay Kit. Tear lipocalin and lysozyme were quantified via Western blotting performed on a Phast System. RESULTS.: By definition, the SS and KCS groups both had significantly lower mean Schirmer scores (5.12 ± 5.96 mm and 7.84 ± 7.35 mm) compared with the NDE group (23.83 ± 7.85 mm; p < 0.0001). There was no difference in mean Schirmer scores between SS and KCS groups (p = 0.19). The tear film of the SS group was characterized by significantly reduced (p < 0.0001) total protein and lipocalin concentrations compared with both KCS and NDE groups. No difference between the KCS and NDE groups was found in total protein (p = 0.92) or lipocalin (p = 0.19) concentration. In contrast, the concentration of tear film lysozyme was found to be statistically similar in all three groups examined. No statistically significant correlation was found in any group between mean Schirmer values compared with total protein, lipocalin or lysozyme concentration. CONCLUSION.: Our data demonstrate a biochemical distinction between the Sjogrens group compared with both KCS and control groups, in that both tear lipocalin and total tear protein were significantly reduced. Although correlations were not found between protein measurements and tear flow, a combination of tests including Schirmer I and quantitation of tear film biomarkers may allow for the identification of SS patients without the need for invasive testing. © 2008 American Academy of Optometry.

Dalton,K., Subbaraman,L. N., Rogers,R., Jones,L. Physical properties of soft contact lens solutions. Optometry and Vision Science 2008;85,2:122-128. [ Show Abstract ]


Purpose. To investigate the physical properties of commercially available soft contact lens solutions.
Methods. The pH, osmolality, surface tension (ST), and viscosity of various soft contact lens solutions were measured at room temperature. Viscosity measurements were also taken at 34°C. The solutions examined were Opti-Free Express (OFX), Opti-Free RepleniSH (OFR), Complete Moisture Plus (COM), UltraCare (UC), ReNu MultiPlus, Sensitive Eyes, AOSept (AO), Clear Care, SoloCare Aqua, and SoftWear saline. The peroxide solutions were measured before and after neutralization.
Results. The pH of most solutions was close to neutral (range 7.00-7.36), except for OFX and neutralized AO and Clear Care. The osmolality values of most solutions were in the 275 to 310 mOsm/kg range. OFX exhibited a significantly lower osmolality (225 mOsm/kg; p < 0.001), whereas UC was significantly higher (329 mOsm/kg; p < 0.001). Neutralized AO and SoftWear saline had ST values of approximately 67 mN/m. OFX, OFR, and SoloCare Aqua exhibited low ST values in the 30 to 35 mN/m range. The remaining solutions exhibited intermediate ST values of approximately 40 mN/m. These three groupings were significantly different (p < 0.001). The average viscosity of most solutions at room temperature was between 0.95 and 1.26 cP, except for COM (3.02 cP; p < 0.001). At 34°C, the average viscosity of most solutions was between 0.70 and 0.83 cP, except for COM, which had a viscosity of 1.92 cP (p < 0.001). The un-neutralized peroxide solutions had very different pH and osmolality values from all the solutions that would directly contact the eye (p < 0.001). Their viscosity and ST values were similar (p = NS).
Conclusions. This study detailed many physical properties of soft lens solutions that are not readily available and indicated that certain properties vary significantly among these products.

Dumbleton,K. A., Woods,C. A., Jones,L. W., Fonn,D. Comfort and adaptation to silicone hydrogel lenses for daily wear. Eye and Contact Lens 2008;34,4:215-223. [ Show Abstract ]

Objectives. To investigate initial comfort and adaptation of currently successful low oxygen transmissibility soft lens wearers refitted with silicone hydrogel (SH) lenses for daily wear. Methods. Fifty-five subjects were enrolled in a subject-masked 5-month clinical trial in which they wore 5 SH lenses in a randomized, crossover design. Comfort, burning, and dryness were rated on scales of 0 to 100 immediately on insertion and the time for lens settling was recorded. Symptoms were then rated at various times, using BlackBerry wireless communication devices (Research in Motion, Waterloo, Canada), during the day for 2 cycles of 2 weeks wear for each lens type. Results. Comfort immediately on insertion varied between lens types (P=0.002). All lens types were reported by the subjects to have settled within 30 to 45 sec of insertion (P=0.14) and "settled" comfort was greater than comfort immediately on insertion (P<0.001). Comfort within the first hour of wear also varied between lens types (P=0.02). Comfort during the day decreased significantly for all lenses (P=0.001), but there was no difference between lenses (P=0.19) and no effect of lens age (P=0.15). The wearing times were greater with the SH lenses than the habitual lenses worn before study commencement (P=0.001). Overall performance of the lenses after 4 weeks was high, with no difference between lenses (P=0.45). Conclusions. Initial comfort and adaptation to all SH lenses were good and no differences in the overall ratings were found between the 5 SH lenses investigated. Decreased comfort was noted later in the day with all lens types, but longer wearing times were reported with the SH lenses than previous hydroxyethyl methacrylate-based lenses. © 2008 Contact Lens Association of Ophthalmologists, Inc.

Glasier,M. -A, Keech,A., Sheardown,H., Subbaraman,L. N., Jones,L. Conformational and quantitative characterization of lysozyme extracted from galyfilcon and senofilcon silicone hydrogel contact lenses. Current eye research 2008;33,1:1-11. [ Show Abstract ]

PURPOSE: To compare two solvents for retrieval of lysozyme deposited on a silicone hydrogel (SH) contact lens material galyfilcon A (GA; Acuvue Advance). METHODS: Two buffers used were 50:50 acetonitrile/0.02% trifluoroacetic acid (buffer 1) and 50:50 acetonitrile/50 mM NaOH (buffer 2). RESULTS: Extraction efficiency from GA lenses was 74% (buffer 1) and 83% (buffer 2). Buffer 2 decreased lysozyme activity > buffer 1. Ex vivo GA lenses showed total protein deposition of 2-16 microg/lens with total lysozyme deposition of 0.3-3.9 microg/lens. CONCLUSIONS: We have developed a low acid strength extraction buffer that can be used to efficiently extract active lysozyme protein from novel siloxane-based contact lens materials.

Glasier,M. -A, Subbaraman,L. N., Senchyna,M., Jones,L. A solid-phase assay for the quantitation of total protein eluted from balafilcon, lotrafilcon, and etafilcon contact lenses. Current eye research 2008;33,8:631-640. [ Show Abstract ]

PURPOSE: To compare two variations of a membrane-based protein assay utilizing Amido black (AB) detection with a commercially available 3-(4-carboxybenzoyl) quinoline-2-carboxaldehyde (CBQCA) assay for use in the quantitation of individual tear proteins, pooled human tear proteins, and protein extracted from ex vivo lotrafilcon A, balafilcon A, and etafilcon A contact lens materials. METHODS: Ex vivo contact lens extracts, pooled human tears, and individual tear proteins (human serum albumin (HSA), bovine lactoferrin, human secretory immunoglobulin A (sIgA), human lysozyme) were subjected to three solid-phase assays: AB on polyvinylidene difluoride (AB on PVDF) and AB on nitrocellulose (AB on NC) and the CBQCA assay. Micro-bicinchonic acid (micro-BCA) assay was also employed with lens extracts to determine total protein concentration. Individual and pooled tear proteins were referenced to a micro version of the quantitative ninhydrin protein assay. RESULTS: The CBQCA demonstrated the greatest overall sensitivity and lowest intra- and inter-assay variability. AB on NC demonstrated the most accurate ability to quantify total protein in pooled human tear samples, although it also displayed the greatest protein-to-protein variation using individual tear proteins. The CBQCA assay displayed the greatest cross-reactivity with unworn balafilcon and lotrafilcon lens extracts, whereas AB on NC demonstrated the least. AB on NC measured similar amounts of total protein in extracted ex vivo lenses as the CBQCA assay if background interference was subtracted from CBQCA values. AB on PVDF measured the lowest amount of deposited protein from ex vivo lenses. CONCLUSION: Both the AB on NC and CBQCA assays can be used to measure protein in extracts of lotrafilcon, balafilcon, and etafilcon lens materials.

Haque,S., Fonn,D., Simpson,T., Jones,L. Epithelial thickness changes from the induction of myopia with CRTH RGP contact lenses. Investigative Ophthalmology and Visual Science 2008;49,8:3345-3350. [ Show Abstract ]

PURPOSE. To investigate changes in epithelial thickness after overnight wear of CRTH rigid gas-permeable (RGP) lenses (Paragon Vision Sciences, Mesa, AZ) for the correction of hyperopia. METHODS. Twenty subjects wore a +3.50 D hyperopia-correcting CRTH lens on one eye for a single night in an attempt to induce myopia (first study). The untreated eye served as the control. Corneal and epithelial thickness was measured at nine points across the horizontal meridian by OCT. Measurements were obtained the night before lens wear, immediately after lens removal the next morning, and 1, 3, 6, and 12 hours after removal. Measurements were obtained 28 hours later, to observe recovery. Then, the attempted hyperopic corrections of +1.50 and +3.50 D were evaluated, using CRTH lenses in both eyes of 20 subjects for a single night (second study). RESULTS. All values were compared to baseline unless otherwise stated. In the first study, the treated eye's central and midperipheral epithelial thickness increased by 21.5% ± 8.6% and 13.3% ± 7.6%, respectively, after lens removal (P < 0.001). The control eye's central epithelial thickness (CET) increased by 7.1% ± 6.0% (P < 0.05). In the second study, CET increased by 17.6% ± 8.5% (P < 0.001) in the +3.50 D-treated eye and by 13.3% ± 4.8% (P < 0.001) in the +1.50 D-treated eye. Midperipheral epithelial thickening was 5.9% ± 4.7% (P < 0.05) in the +3.50 D-treated eye and 6.0% ± 6.3% (P < 0.05) in the +1.50 D-treated eye. CONCLUSIONS. CRTH lenses, designed to correct hyperopia, when worn overnight, caused an increase in CET. The amount of epithelial change seemed to differ with modified lens design. Copyright © Association for Research in Vision and Ophthalmology.

Hui,A., Boone,A., Jones,L. Uptake and release of ciprofloxacin-HCl from conventional and silicone hydrogel contact lens materials.. Eye & contact lens 2008;34,5:266-271. [ Show Abstract ]

OBJECTIVES: To investigate the uptake and release characteristics of the antibiotic ciprofloxacin-HCl in conventional and silicone hydrogel lenses, and evaluate their potential as therapeutic drug delivery devices. METHODS: Nine differing soft contact lens materials were soaked in a 0.3% ciprofloxacin-HCl solution at 34 degrees C. The uptake of the drug into the lenses was measured by the change in concentration over 24 hours using fluorescence spectrophotometry. The lenses were then placed in a buffered saline solution, and the release of the drug from the lenses was also measured using spectrophotometry. RESULTS: The release of drug varied from 0.016 +/- 0.004 mg/lens for lotrafilcon A lenses to 0.42 +/- 0.03 mg/lens for etafilcon A lenses, with an average of 0.133 mg/lens. The 3 conventional lenses used in the study released a statistically significantly different amount of drug when compared with the silicone hydrogels. The release of drug was very rapid, with drug release reaching a plateau after no more than 10 minutes for the majority of the lenses. The majority of the lenses were able to release enough drug to achieve minimum inhibitory concentration 90 for most resistant ocular pathogens. Ciprofloxacin was found to heavily precipitate on the etafilcon A lenses during the release phase at physiologic pH. CONCLUSION: While balafilcon A released the most drug from the silicone hydrogel materials, all materials released the drug too quickly to be effective as drug delivery devices.

Luensmann,D., Jones,L. Albumin adsorption to contact lens materials: A review. Contact Lens and Anterior Eye 2008;31,4:179-187. [ Show Abstract ]

During contact lens wear, tear film components such as lipids, mucins and proteins tend to deposit on and within the lens material and may cause discomfort, reduced vision and inflammatory reactions. The tear film protein that has attracted most interest when studying contact lens deposition is the small (14 kDa), positively charged protein lysozyme. Albumin, which is a much larger protein (66 kDa) with an overall net negative charge is also of interest, and shows very different adsorption patterns to lysozyme. The concentration of albumin in the tear film is relatively low compared to the concentration in blood serum, but this value increases markedly under various conditions, including when the eye is closed, during contact lens wear and in various dry eye states. Gaining an understanding of the manner in which albumin deposits on biomaterials is of importance for contact lens wear, as well as for other medical applications where HEMA-based materials are used for implants, artificial blood vessels or drug delivery devices. This review paper summarizes the impact of individual material compositions, water content, hydrophobicity and electrostatic attraction on the adsorption behavior of the protein albumin.

Simpson,T. L., Situ,P., Jones,L. W., Fonn,D. Dry eye symptoms assessed by four questionnaires. Optometry and Vision Science 2008;85,8:E692-E699. [ Show Abstract ]

PURPOSE.: To establish the relationships between commonly used questionnaires including Dry Eye Questionnaire, McMonnies Questionnaire, and Ocular Surface Disease Index, and to test the construct and face validity of the simple Subjective Evaluation of Symptom of Dryness. METHODS.: Ninety-seven non-contact lens wearing subjects were enrolled in the study and classified into either a "dry" and "non-dry" group using a single score from an initially applied subjective evaluation of symptom of dryness. The four questionnaires were then completed in a random order. The unidimensionality and accuracy of the responses was assessed using Rasch and receiver (or relative) operating characteristics curve analysis and the characteristics of and association between symptoms were compared using non-parametric statistics. RESULTS.: The responses from the Dry Eye Questionnaire, McMonnies Questionnaire, and Ocular Surface Disease Index met the Rasch analysis criterion of unidimensionality. Each test separated the symptomatic and asymptomatic groups well [all receiver (or relative) operating characteristics area-under-the-curve statistics at least 0.88] and there were significant associations between the results from each questionnaire (all Spearman ρ at least 0.64). CONCLUSIONS.: The results illustrate that different questionnaire-based instruments examining symptoms in controls and symptomatic subjects derive unidimensional data that are similar inasmuch as the overall scores are highly correlated. The data also point to the utility of a quick, three-question screening tool in dry eye research. © 2008 American Academy of Optometry.

Situ,P., Simpson,T. L., Fonn,D., Jones,L. W. Conjunctival and corneal pneumatic sensitivity is associated with signs and symptoms of ocular dryness. Investigative Ophthalmology and Visual Science 2008;49,7:2971-2976. [ Show Abstract ]

PURPOSE: To investigate the relationships of dry eye symptoms and corneal and conjunctival sensitivity to pneumatic stimulation, tear film stability, and clinical ocular surface characteristics in symptomatic and asymptomatic subjects. METHODS: Ninety-seven subjects were enrolled and grouped by a questionnaire-based single score for symptoms of ocular dryness (none to trace, non-dry group; mild to severe, symptomatic group); 43 were symptomatic and 54 were non-dry. Corneal (K) and conjunctival (C) sensitivities were measured with a computer-controlled Belmonte pneumatic (room temperature) stimulus. Symptoms were assessed according to the Ocular Surface Disease Index (OSDI). Ocular surface staining with fluorescein (FL) and lissamine green (LG), noninvasive tear film break-up time (NIBUT), and the phenol red thread test (PRT) were assessed. RESULTS: The symptomatic group showed lower K and C thresholds (P < 0.01), greater corneal FL and conjunctival LG staining, and shorter NIBUT than did the non-dry eye group (all others P < 0.05). The OSDI scores were higher in the symptomatic group (P < 0.001). K and C thresholds and NIBUT were inversely correlated with the OSDI and corneal and conjunctival staining (all P < 0.05). The K and C threshold and NIBUT (all P < 0.01) correlated positively. Step-wise multiple regression analysis showed that ocular surface sensitivity and NIBUT were significant predictors of the OSDI. CONCLUSIONS: Ocular irritation assessed with the OSDI is associated with ocular surface hyperesthesia to cooling, corneal epitheliopathy, and tear film instability. Although cause and effect are unclear, the analysis showed that altered corneal and conjunctival sensory processing and tear film attributes are essential aspects of what characterizes dry eye.

Situ,P., Simpson,T. L., Jones,L. W., Fonn,D. Conjunctival and corneal hyperesthesia in subjects with dryness symptoms. Optometry and Vision Science 2008;85,9:867-872. [ Show Abstract ]

PURPOSE.: To compare conjunctival and corneal sensitivity in noncontact lens wearing subjects with and without symptoms of ocular dryness, stratified by age and gender. METHODS.: Ninety-seven subjects were enrolled, 54 of whom were asymptomatic and 43 of whom were symptomatic of ocular dryness. A single score for the symptom of dryness was used to classify nondry eye (scores of none to trace) and dry eye symptomatic (scores of mild to severe) groups. The subjects were further stratified into "younger" (19 to 49 years) and "older" age groups (50 to 80 years). Conjunctival and corneal sensitivity of the right eye was measured at the central cornea and temporal conjunctiva, using a computer-controlled pneumatic esthesiometer with stimulus temperature set at 20°C. The ascending method of limits was used to determine the thresholds. RESULTS.: Conjunctival and corneal thresholds were significantly lower in the dry eye symptomatic than in the nondry eye group (both p 0.05). Conjunctival threshold in the nondry eye women was lower than the men (p 0.05). CONCLUSIONS.: Conjunctival and corneal sensitivity to pneumatic cool stimulation is increased in subjects with symptoms of ocular dryness. This hyperesthesia seems to be more significant in the conjunctiva. © 2008 American Academy of Optometry.

Teichroeb,J. H., Forrest,J. A., Jones,L. W., Chan,J., Dalton,K. Quartz crystal microbalance study of protein adsorption kinetics on poly(2-hydroxyethyl methacrylate). Journal of colloid and interface science 2008;325,1:157-164. [ Show Abstract ]

The interaction of macromolecules with artificial biomaterials may lead to potentially serious complications upon implantation into a biological environment. The interaction of one of the most widely used biomaterials, polyHEMA, with lysozyme, bovine serum albumin (BSA), and lactoferrin was investigated using quartz crystal microbalance (QCM). The concentration dependence of adsorption was measured for the aforementioned proteins individually as well as for lysozyme-BSA, and lysozyme-lactoferrin combinations. An extension of Voinova's viscoelastic model to n layers was used to create thickness-time graphs for adsorption. For each of lactoferrin and lysozyme, two distinctly different timescales of adsorption could be differentiated. However, the mechanisms of adsorption appeared to differ between the two. Negative dissipation shifts were measured for low concentrations of lysozyme, trending to positive dissipation at higher concentrations. This suggested that lysozyme was adsorbed initially into the matrix, stiffening the hydrogel, and later onto the surface of polyHEMA. Additionally, trials with commercial no-rub cleaning solutions indicated little added effectiveness over buffer solutions. Mixtures of proteins showed behaviour which differed in some cases from the simple combination of single protein adsorption experiments. Crown Copyright © 2008.

Van Beek,M., Jones,L., Sheardown,H. Hyaluronic acid containing hydrogels for the reduction of protein adsorption. Biomaterials 2008;29,7:780-789. [ Show Abstract ]

Recently, new contact lens materials have been introduced which are reported to improve comfort by incorporating wetting agents either in a releasable or nonreleasable form. In the present work, model lens materials based on poly(2-hydroxyethyl methacrylate) (pHEMA) were developed which incorporate releasable or crosslinked and therefore physically entrapped hyaluronic acid (HA) of various molecular weights as a wetting agent. Crosslinked HA, despite being only present in very small amounts, resulted in consistently lower water contact angles over 4 h in comparison to controls, indicating that HA is present at the interface and was not being released over time. The presence of HA in the material was further confirmed by increases in the glass transition temperature measured by differential scanning calorimetry (DSC), and small increases in the stiffness as measured by Instron testing. This crosslinking procedure appeared to have no effect on optical transparency using 35 kDa HA, whereas small decreases in optical transparency at higher wavelengths were noted for the 169 kDa HA crosslinked material, as measured by UV spectrophotometry. Most importantly, protein adsorption results indicated that the adsorption of all proteins studied was considerably decreased by the presence of the small amount of crosslinked HA. The results provide insight into the mechanisms of comfort improvement with commercially available lens materials and suggest that HA containing materials may have significant potential for use in contact lens applications. © 2007 Elsevier Ltd. All rights reserved.

Varikooty,J., Srinivasan,S., Jones,L. Atypical manifestation of upper lid margin staining in silicone hydrogel lens wearers with symptoms of dry eye. Contact Lens and Anterior Eye 2008;31,1:44-46. [ Show Abstract ]

Purpose: To report an atypical manifestation of upper lid margin staining (ULMS) that occurred in adapted silicone hydrogel (SH) contact lens wearers who complained of ocular surface dryness. Methods: Sequential staining with sodium fluorescein (FL) and lissamine green (LG) strips was performed in 38 SH lens wearers. The "wiper area" of the upper lid was examined with the slit lamp, at 8× and 12× magnifications. Results: Four out of 38 subjects (10.5%) showed fimbriated or "feathery" extensions from the superior margin of the subtarsal fold onto the upper tarsal plate. The extent of these feathery extensions varied between subjects, with a mean (±S.D.) length of 2 ± 0.8 mm. In all cases a broad band of staining with both FL and LG was demonstrated, which extended along the entire length of the lid margin. Conclusion: The staining patterns shown on the subjects' upper lid margins and tarsal plates suggest that ULMS may include more complex variants. The putative tissue damage revealed through the staining, points to a mechanism not simply restricted to the upper lid margin. © 2007 British Contact Lens Association.

2007

Bitton,E., Keech,A., Simpson,T., Jones,L. Variability of the analysis of the tear meniscus height by optical coherence tomography. Optometry and Vision Science 2007;84,9:E903-E908. [ Show Abstract ]

PURPOSE. Tear meniscus height (TMH) is an established parameter indicative of tear film volume and has recently been determined using an optical coherence tomographer (OCT). The purpose of this study was to evaluate the inter and intra observer variability in TMH assessment using OCT. METHODS. Ten subjects (6 M, 4 F; aged 32.5 ± 6.4 years) had 10 consecutive scans taken of their inferior central tear meniscus (5 scans originating at 90° and 5 origination at 270°) using the OCT2 (Humphrey-Zeiss). Images were analyzed by two observers using custom software on three separate occasions. Following a training session among observers, the images were reevaluated to assess differences in variability. Data were analyzed for differences within and across examiners, for the effect of examiner training and between scan directions. RESULTS. The mean TMH and tear volume collapsed across subjects were between 0.24 and 0.25 mm and 25 to 27 nL/mm, respectively. No difference was noted within observers. An interobserver mean volume difference (p = 0.044) was present but was eliminated post training (p = 0.167). Variability was less with scans originating at 90°. CONCLUSIONS. The values of the TMH and tear volume are similar to those reported in the literature. Due to the interobserver differences observed, a training session between examiners may prove to be valuable, especially in a large or multicenter study. © 2007 American Academy of Optometry.

Woods,C. A., Jones,D. A., Jones,L. W., Morgan,P. B. A seven year survey of the contact lens prescribing habits of Canadian optometrists. Optometry and Vision Science 2007;84,6:505-510. [ Show Abstract ]

PURPOSE: Little is known about the contact lens prescribing habits of optometrists in North America. The purpose of this survey was to obtain data on the types of lenses and solutions prescribed by Canadian optometrists. METHODS: One thousand Canadian optometrists were surveyed annually over seven consecutive years (2000 to 2006; n = 7000) on their contact lens prescribing preferences. Each survey requested a range of information about the contact lenses prescribed to the first 10 patients after its receipt. RESULTS: Over this time period, 1008 (14.4%) of the surveys were returned, providing data on 9383 fits. During the seven-year period, the ratio of male:female fits was 1:2 (3123:6217, 43 not reported), with a mean age of 31.3 +/- 13.6 years (range 2 to 82 years). The ratio of new fits to refits was 2:3 (3780:5518, 85 not reported), with 91.3% of all fits being soft contact lenses (SCL). Of the SCL fits, 59.5% were spherical, 28.5% toric, 9.7% multifocal, and 2.3% cosmetic tints. Gas permeable (GP) fits were 46.6% spherical, 18.6% toric, 19.5% multifocal, and 6.6% were for orthokeratology (OK). Over the seven-year period, SCL prescribed for continuous wear (CW) increased from 3.2% to 14.3% between 2000 and 2004 and reduced to 8.1% in 2006, for all fits. The use of mid-water content (MWC) materials decreased from 34.6% to 2.7% and the use of silicone hydrogel (SH) lenses increased from 61.4% to 96.2%, for all CW fits. GP lens continuous wear increased from 0.7% to 30.6% of all GP lens fits by 2006. Daily wear (DW) of SH lenses decreased from 49.6% (2000) to 33.7% (2004) and then increased to 86.1% in 2006, for SH fits. MWC SCL fit on a monthly planned replacement (PR) basis reduced in popularity over the seven-year period (75.0% to 39.9%) and in 2006 more patients were fit overall with SH lenses (42.9%). The use of non-PR SCL declined from 20.5% to 4.5% of all fits. Fitting of low-water content lenses also declined (15.1% to 7.0%). High-water content (5.4% to10.2%) and SH lenses (5.4% to 42.9%) both increased. By 2006, the majority of GP lenses fit were with high Dk (HDK) materials (50.3%). CONCLUSIONS: The preferred contact lens modality for Canadian optometrists appears to be DW SCL, which are replaced monthly. The proportion of lenses used for CW peaked in 2004, with SH SCL being the preferred material. The market share for GP lenses remains relatively unchanged, with an increasing proportion used for OK and CW. The launch of DW SH lenses in 2004 resulted in a marked increase in their reported fits, with a similar effect following the launch of a HDK GP lens material for CW.

Dracopoulos,A., Dixon,D. G., Jones,L. W., Sivak,J. G., Bantseev,V. In vitro assessment of medical device toxicity: Interactions of benzalkonium chloride with silicone-containing and p-HEMA-containing hydrogel contact lens materials. Eye and Contact Lens 2007;33,1:26-37. [ Show Abstract ]

PURPOSE. To analyze the interactions of benzalkonium chloride (BAK) with silicone-containing (lotrafilcon A and galyfilcon A) and p-HEMA-containing (etafilcon A and vifilcon A) hydrogel contact lenses and to examine the possibility of using sodium fluorescein permeability assay (SFPA), 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the bovine lens assay in conjunction with confocal laser scanning microscopy (CLSM) as a battery of in vitro alternatives to evaluate the potential toxicity of soft contact lenses. METHODS. Four soft contact lens types (Focus Monthly [vifilcon A], Focus NIGHT & DAY [lotrafilcon A], ACUVUE Advance With Hydraclear [galyfilcon A], and SUREVUE [etafilcon A]) were soaked for 24 hours in various concentrations of BAK (1%, 0.1%, 0.01%, and 0.001%) in 20-mL glass vials. After 24 hours, the lenses were gently washed in Hanks' Balanced Salt Solution (HBSS), placed in 5 mL of HBSS, and incubated for a total of 7 days at 37°C, 5% CO2. BAK released into HBSS (i.e., the extract) was recovered from the vials and used as the test chemical in the SFPA (epithelium integrity), MTT assay (cellular viability), and the bovine lens assay with CLSM (mitochondrial metabolism and optical properties). The amount of BAK extracted from the various contact lenses was measured using an Abbe refractometer. Negative controls consisted of HBSS and contact lenses subjected to the same conditions as the treated contact lenses, but without BAK. RESULTS. Extracts obtained from soaking Focus Monthly lenses in BAK caused the most damage to the epithelium and mitochondrial metabolism. However, at 0.1% BAK extraction, all lens extracts showed increased levels of back vertex distance variability of the cultured bovine lens. CONCLUSIONS. Unexpectedly, lenses extracted with HBSS showed SFPA and MTT assay responses and an observed effect on the bovine lens epithelium visualized by CLSM, indicating that unknown chemical agents may be leached from contact lens polymers. © 2007 Lippincott Williams & Wilkins, Inc.

Duench,S., Simpson,T., Jones,L. W., Flanagan,J. G., Fonn,D. Assessment of variation in bulbar conjunctival redness, temperature, and blood flow. Optometry and Vision Science 2007;84,6:511-516. [ Show Abstract ]

PURPOSE. To assess the diurnal variation in bulbar conjunctival redness, conjunctival temperature, and conjunctival blood flow. METHODS. Bulbar redness was quantified by CIE u' chromaticity using a SpectraScan PR650 spectrophotometer. Conjunctival temperature was measured using a Tasco-Thi 500 infrared thermometer. Measurements of conjunctival blood flow were obtained using a modified Heidelberg Retinal Flowmeter (HRF). Measurements on 10 subjects were made on a periodic basis over the day and on waking. RESULTS. For each factor measured a cyclical pattern was observed, with highest values on waking, a reduction in values towards mid-day, and then a gradual increase over the remainder of the day. There was a significant effect of time for redness, temperature, and conjunctival blood flow (p < 0.001 for all three variables), with no significant difference in the cyclical pattern between eyes being observed (p = NS). CONCLUSIONS. Diurnal bulbar redness, temperature, and conjunctival blood flow variation may be objectively quantified and all three are lowest during the middle of the day and maximal at the start of the day. This information should be considered when undertaking studies in which redness, temperature, and ocular surface blood flow are important outcome variables and time of day is a potential confounding factor. © 2007 American Academy of Optometry.

Haque,S., Fonn,D., Simpson,T., Jones,L. Corneal refractive therapy with different lens materials, Part 1: Corneal, stromal, and epithelial thickness changes. Optometry and Vision Science 2007;84,4:343-348. [ Show Abstract ]

PURPOSE. To assess the corneal swelling response to two myopic correction corneal refractive therapy (CRT) lenses of varying Dk/t values, worn for a single night. Change in thickness of the total cornea, stroma, and epithelium was measured across the horizontal meridian using optical coherence tomography (OCT). METHODS. In this double-masked, randomized study, twenty subjects wore a CRT design lens in each eye, manufactured from Menicon Z (MenZ; Dk/t = 91) and Equalens II (EqII; Dk/t = 47) materials. Baseline corneal thickness was measured centrally and at four points either side of the central cornea using OCT, the night before sleeping at the Centre for Contact Lens Research. The next morning, lenses were removed, and thickness measurements were repeated 1, 3, 6, and 12 h after removal. RESULTS. On lens removal, the MenZ eye had central and paracentral corneal swelling (mean ± SD) of 4.1 ± 2.0% and 5.6 ± 2.4%, and the EqII eye had 5.8 ± 2.6% and 7.0 ± 2.6%. These values were significantly different from baseline (ReANOVA; p 0.05). Stromal swelling values on lens removal were 5.7 ± 2.2% centrally and 5.5 ± 3.0% mid-peripherally (MenZ) and 7.7 ± 3.1% centrally and 6.6 ± 2.9% mid-peripherally (EqII) (all p < 0.001 from baseline). Central stromal swelling was different between eyes at lens removal (p < 0.001). Stromal thickness in both eyes returned to baseline values within 3 h. CONCLUSION. The higher-Dk/t MenZ material caused significantly less overnight corneal and stromal swelling than the Eqll material, which reinforces the need to prescribe lenses with high Dk/t for overnight wear. Neither central epithelial thinning nor paracentral thickening are significantly affected by Dk/t. © 2007 American Academy of Optometry.

Klenkler,B., Sheardown,H., Jones,L. Growth factors in the tear film: Role in tissue maintenance, wound healing, and ocular pathology. Ocular Surface 2007;5,3:228-239. [ Show Abstract ]

Numerous biologically active growth factors are secreted by the lacrimal gland and distributed via the tears over the ocular surface where they affect cellular proliferation, migration, differentiation, and survival. The role of growth factors and their receptors in maintenance of tissue homeostasis and wound healing continues to be elucidated, and the effect of growth factor imbalances In ocular surface diseases is just beginning to be understood. For Instance, in eyes with ocular surface diseases, Including conjunctivitis, corneal erosion, keratitis, and corneal ulcers, epidermal growth factor release rates have been shown to be significantly lower than in normal eyes during reflex tearing. Future research into the mechanisms of dry eye disease will focus on reasons for decreased tear and growth factor production in the neuronal reflex loop or the acinar lacrimal gland cells. Animal models to test therapeutic approaches must be developed. © 2007 Ethis Communications, Inc.

Lorentz,H., Jones,L. Lipid deposition on hydrogel contact lenses: How history can help us today. Optometry and Vision Science 2007;84,4:286-295. [ Show Abstract ]

The tear film is a complex fluid that is precisely maintained and which is essential to the health of the ocular surface. One of the major components of the tear film is lipid, which is produced by the meibomian glands and serves many important functions on the ocular surface. It is estimated that there are more than 45 individual lipids within the tear film, which vary greatly in their structure and properties. The composition of the lipid within the tear film has an enormous influence on the stability of the tear film, with a subsequent impact on the occurrence of dry eye and the ultimate success of contact lens wear. The purpose of this review article is to describe the composition of the tear film lipids and their interaction with contact lens materials, with a particular emphasis on how the chemistry of novel silicone hydrogel materials has resulted in clinicians needing to understand the deposition of lipids onto contact lenses and how they may best manage this complication.

Lorentz,H., Rogers,R., Jones,L. The impact of lipid on contact angle wettability. Optometry and Vision Science 2007;84,10:946-953.

Luensmann,D., Glasier,M. -A, Zhang,F., Bantseev,V., Simpson,T., Jones,L. Confocal microscopy and albumin penetration into contact lenses. Optometry and Vision Science 2007;84,9:839-847. [ Show Abstract ]


Purpose. To develop a novel in vitro method to detect the depth of penetration of the tear film protein albumin into contact lens materials using confocal laser scanning microscopy (CLSM).
Methods. A poly-HEMA-based hydrogel (etafilcon A) and a silicone hydrogel material (lotrafilcon B) were examined. In vitro, bovine serum albumin (BSA) was labeled with 5-(4,6-dichloro-s-triazin-2-ylamino) fluorescein hydrochloride (DTAF). The lenses were incubated in this protein solution (0.5 mg/ml) at 37°C. After 1 and 7 days incubation, the lenses were examined using CLSM (Zeiss 510, config. META 18) and the location of the fluorescently labeled BSA was identified.
Results. BSA adsorption on the surface and penetration into the lens matrix occurred at a higher concentration for etafilcon compared to lotrafilcon (p < 0.001). For both materials, BSA was detected on the surface after 1 day of incubation. Significant levels of BSA were detected within the matrix of etafilcon after as little as 1 day (p < 0.001), but no BSA was detected in the matrix of lotrafilcon at any time (p > 0.05).
Conclusion. CLSM can be successfully used to examine the depth of penetration of fluorescently labeled proteins into various hydrogel polymers. Our results show that etafilcon lenses both adsorb BSA on the surface and absorb BSA within the matrix, whereas lotrafilcon B adsorbs small amounts of BSA on the surface only.

Srinivasan,S., Chan,C., Jones,L. Apparent time-dependent differences in inferior tear meniscus height in human subjects with mild dry eye symptoms. Clinical and Experimental Optometry 2007;90,5:345-350. [ Show Abstract ]

PURPOSE: The aim of the study was to track the volume of tears contained in the inferior tear meniscus over the course of the day in subjects with symptoms of mild dry eye and a control asymptomatic group. METHODS: Forty non-contact lens-wearing subjects (aged 27 +/- 6 years) were enrolled in this investigator-masked study. They were divided into 'dry eye' (DE) and 'non-dry eye' (NDE) individuals based on their responses to the Allergan Subjective Evaluation of Symptoms of Dryness (SESOD) questionnaire. Measurement of the tear meniscus height (TMH) was undertaken on the centre of the right eye at 9:00 am, noon, 3:00 pm, 6:00 pm and 9:00 pm on the lower lid using a non-contact, non-invasive optical coherence tomographer (OCT). The TMH was determined from scanned images using customised software. RESULTS: A monotonous and significant reduction in the central TMH occurred over the course of the day in both groups (p < 0.05), with the values constantly decreasing (NDE = 0.162 to 0.125 mm; DE = 0.154 to 0.121 mm). While the TMH values in the DE group were always lower than the NDE group, these were not significantly different at any time (p > 0.05). CONCLUSIONS: A diurnal reduction in tear volume, as assessed by evaluation of the inferior TMH, may be one of the reasons responsible for the common increase in end-of-day ocular dryness symptoms reported by many patients in clinical practice.

Srinivasan,S., Joyce,E., Jones,L. W. Tear osmolality and ferning patterns in postmenopausal women. Optometry and Vision Science 2007;84,7:588-592. [ Show Abstract ]

PURPOSE: To compare tear osmolality and ferning patterns in postmenopausal women (PMW) with and without dry eye symptoms. METHODS: Thirty-seven healthy PMW (>50 years of age), not on hormone replacement therapy, were categorized as being symptomatic or asymptomatic of dry eye based on their responses to an Allergan "Single-Item Score Dry Eye Questionnaire" (SIDEQ). They subsequently completed the Allergan "Ocular Surface Disease Index" (OSDI) questionnaire. Tear samples were collected from participants to evaluate osmolality and ferning patterns. A novel freezing point depression osmometer (Advanced Instruments Inc., Model 3100 Tear Osmometer), was used to measure the osmolality of the tear film. The tear ferning test was performed and evaluated for the quality of ferning based on the Rolando grading system. RESULTS: SIDEQ responses revealed 21 symptomatic and 16 asymptomatic participants. The OSDI total score was 6.5 +/- 5.9 for the non-dry-eyed (NDE) group and 25.7 +/- 12.4 for the dry-eyed (DE) group. The subscores for the DE group were significantly greater than the NDE group (p < 0.001). Osmolality values in DE individuals were significantly different from NDE (328.1 +/- 20.8 vs. 315.1 +/- 11.3 mOsm/kg; p = 0.02). Fifty percent of the DE participants showed type II ferning patterns and 29% of the DE participants showed type III ferning patterns, whereas the NDE participants showed either type I (44%) or II (66%) ferning patterns. There was a significant difference between the DE and NDE participants for the ferning patterns (p = 0.019). There was no significant correlation between tear osmolality and tear ferning (DE: r = 0.12; p > 0.05, NDE: r = -0.17; p > 0.05). CONCLUSIONS: Osmolality in mild and moderately DE PMW is higher than in NDE PMW and tear ferning is a rapid, simple, noninvasive laboratory procedure that indicates altered tear quality in PMW with symptoms of dry eye.

Subbaraman,L. N., Glasier,M. A., Senchyna,M., Sheardown,H., Jones,L. Extraction efficiency of an extraction buffer used to quantify lysozyme deposition on conventional and silicone hydrogel contact lens materials. Eye and Contact Lens 2007;33,4:169-173. [ Show Abstract ]

PURPOSE: Extracting lysozyme from Food and Drug Administration group IV etafilcon lenses by using 0.2% trifluoroacetic acid and acetonitrile (TFA/ACN) is a well-established procedure. TFA/ACN has been the extraction buffer of choice for extracting proteins from silicone hydrogel contact lenses. The purpose of this study was to determine the efficiency of TFA/ACN in extracting lysozyme from silicone hydrogel and etafilcon lenses by using an in vitro model. METHODS: ACUVUE 2, Focus NIGHT & DAY, O2 Optix, PureVision, and ACUVUE Advance lenses were incubated in simple lysozyme solution and a complex artificial tear solution consisting of multiple tear components containing lysozyme labeled with iodine 125. All the silicone hydrogel lenses were incubated for 28 days, whereas the ACUVUE 2 lenses were incubated for 7 days at 37 degrees C with constant rotation. After the incubation period, radioactive counts were determined, and the lenses were placed in an appropriate volume of the buffer for 24 hours in darkness. The lenses were removed from the buffer, and radioactive counts were determined again. RESULTS: Extraction efficiencies for lysozyme from the artificial tear solution were 97.2% +/- 1.2% for ACUVUE 2, 64.3% +/- 6.2% for Focus NIGHT & DAY, 62.5% +/- 5.6% for O2 Optix, 53.5% +/- 5.8% for PureVision, and 89.2% +/- 3.4% for ACUVUE Advance. Results were similar for the lysozyme extracted after incubating in the simple lysozyme solution. CONCLUSIONS: TFA/ACN is extremely efficient at extracting lysozyme deposited on etafilcon lenses. However, it does not extract all the lysozyme deposited on silicone hydrogel lenses, and alternative extraction procedures should be sought.

Suwala,M., Glasier,M. -A, Subbaraman,L. N., Jones,L. Quantity and conformation of lysozyme deposited on conventional and silicone hydrogel contact lens materials using an in vitro model. Eye and Contact Lens 2007;33,3:138-143. [ Show Abstract ]

PURPOSE: To determine the activity of hen egg lysozyme (HEL) deposited on conventional and silicone hydrogel contact lens materials by using an in vitro model. METHODS: ACUVUE 2 (etafilcon A), PureVision (balafilcon A), ACUVUE Advance (galyfilcon A), Focus NIGHT & DAY (lotrafilcon A), O2 Optix (lotrafilcon B), Proclear (omafilcon A), and ACUVUE OASYS (senofilcon A) contact lenses were deposited in vitro in a phosphate-buffered solution (PBS) containing 2 mg/mL HEL. Lenses were briefly rinsed in PBS to remove unbound material and extracted in a mixture of acetonitrile and trifluoroacetic acid. After lyophilization, extracts were examined for lysozyme activity by micrococcal assay and total protein by Western blot. RESULTS: In terms of total protein accumulation, ACUVUE 2 showed the most, with 1,800 microg per lens. Proclear was next, with 68 microg per lens, and Focus NIGHT & DAY showed the least, with 2 microg per lens. ACUVUE Advance, ACUVUE OASYS, and O2 Optix accumulated similar amounts of lysozyme, at approximately 6 microg per lens. Lysozyme deposited on ACUVUE 2 showed the greatest activity (91% +/- 5%), and this result was statistically different from all other lens types (P<0.001). Lysozyme deposited on Focus NIGHT & DAY (24% +/- 5%) and O2 Optix (23% +/- 11%) showed the lowest activity. Lysozyme deposits on other lens materials showed intermediate activity (ACUVUE Advance, 60% +/- 15%; ACUVUE OASYS, 51% +/- 9%; PureVision, 58% +/- 8%; and Proclear, 38% +/- 3%). CONCLUSIONS: Silicone hydrogel lenses acquire less lysozyme deposit than conventional group II (Proclear) or group IV (ACUVUE 2) lenses do, and the levels of activity of the lysozyme are highly variable between materials.

2006

Dumbleton,K., Keir,N., Moezzi,A., Feng,Y., Jones,L., Fonn,D. Objective and subjective responses in patients refitted to daily-wear silicone hydrogel contact lenses. Optometry and Vision Science 2006;83,10:758-768. [ Show Abstract ]

PURPOSE. Silicone hydrogel (SiH) lenses offer many physiological advantages for daily wear (DW) in addition to the continuous-wear modality for which they were originally developed. The purpose of this study was to investigate the clinical performance and physiological responses in a group of successful long-term wearers of conventional hydrogel lenses when refitted with DW SiH contact lenses. METHODS. Eighty-seven successful soft lens wearers (8.4 ± 4.7 years of prior lens wear) participated in this study. Bulbar and limbal hyperemia were subjectively graded and digitally photographed for subsequent masked objective evaluation. Subjective symptoms were scored using visual analog scales. In addition, refractive error, corneal curvature, and corneal thickness were measured. All subjects were refitted with Focus Night & Day (lotrafilcon A) SiH lenses; however, to reduce the potential for bias, they were informed that they were being randomly assigned to wear either low oxygen permeability (Dk) lenses or high Dk SiH lenses and were "masked" as to their lens assignment. Subjects returned after 1 week, 1 month, and 2 months of DW, at which time all gradings, photographs, and measurements were repeated. End-of-day subjective symptoms were also graded periodically during the study. RESULTS. Ninety-three percent of subjects were successfully refitted. Both objective and subjective evaluations showed that bulbar and limbal hyperemia decreased significantly in all quadrants during the study (p < 0.001), particularly for those subjects with greater baseline hyperemia (p < 0.001). Subjects reported a concurrent reduction in end-of-day dryness and improved end-of-day comfort compared with their habitual lenses (p < 0.001). No significant changes in refractive error, tarsal papillary response, corneal curvature, or corneal thickness were found during the study. CONCLUSIONS. Hyperemia in contact lens wearers may be attributed to a number of factors, including hypoxia. Refitting existing low Dk lens wearers with SiH lenses on a DW basis can result in a decrease in hyperemia, which may be significant for some subjects and also results in improvements in symptoms of dryness and discomfort. © 2006 American Academy of Optometry.

Haque,S., Simpson,T., Jones,L. Corneal and epithelial thickness in keratoconus: A comparison of ultrasonic pachymetry, Orbscan II, and optical coherence tomography. Journal of Refractive Surgery 2006;22,5:486-493. [ Show Abstract ]

PURPOSE: To compare corneal thickness measurements in individuals with keratoconus using optical coherence tomography (OCT), Orbscan II, and ultrasonic pachymetry and to measure epithelial and stromal thickness in these individuals using OCT. METHODS: Twenty individuals with keratoconus and 20 controls (without keratoconus) were enrolled. The Orbscan II was used to locate the steepest area of the cornea, which was taken to represent the cone apex. Each instrument was used to obtain four total corneal thickness measurements-from the cone apex, corneal center, mid-nasal, and mid-temporal cornea. Optical coherence tomography scans were analyzed to provide epithelial and stromal thickness readings. RESULTS: In individuals with keratoconus, mean central corneal thickness (CCT) measured by ultrasonic pachymetry, Orbscan, and OCT was 494.2±50.0 μm, 438.6±47.7 μm, and 433.5±39.7 μm, respectively. The central keratoconic cornea was 57.7 μm thinner than the normal cornea (post-hoc P.05). CONCLUSIONS: Ultrasonic pachymetry produced the highest corneal thickness readings in the center and apex, compared to Orbscan II and OCT. Centrally, the total cornea, epithelium, and stroma were thinner in individuals with keratoconus than in normal individuals.

Lu,F., Simpson,T., Fonn,D., Sorbara,L., Jones,L. Validity of pachymetric measurements by manipulating the acoustic factor of Orbscan II. Eye and Contact Lens 2006;32,2:78-83. [ Show Abstract ]

PURPOSE. To assess the validity of pachymetric measurements by examining the constancy of the acoustic factor (AF) of the Orbscan II (Orbtek, Bausch & Lomb, Rochester, NY) after overnight rigid gas-permeable (RGP) contact lens wear. METHODS. Twenty participants wore CRT (Paragon Vision Sciences, Mesa, AZ) HDS 100 contact lenses on one eye and control lenses on the contralateral eye for one night while sleeping. Another 24 participants wore CRT lenses on both eyes for one night. Central corneal thickness was measured using optical coherence tomography and Orbscan II on the night before lens use, immediately after lens removal on the following morning, and 1, 3, 6, and 12 hours later. By using optical coherence tomography as a reference, the adjusted AF was calculated by using a least squares method over time. RESULTS. The adjusted AF depended on the corneal thickness in normally hydrated corneas. The adjusted AF and the percentage change of the adjusted AF varied before and after overnight lens wear. There was a strong and significant correlation between the corneal swelling and the percentage change of the adjusted AF (all r at least 0.91, P<0.05). CONCLUSIONS. The adjusted AF is a variable, not a constant. The AF is a function of the corneal thickness and its alteration with, for example, corneal swelling. The validity of the adjusted Orbscan II pachymetric measures using a single AF is untenable. © 2006 Lippincott Williams & Wilkins, Inc.

Subbaraman,L. N., Bayer,S., Glasier,M. -A, Lorentz,H., Senchyna,M., Jones,L. Rewetting drops containing surface active agents improve the clinical performance of silicone hydrogel contact lenses. Optometry and Vision Science 2006;83,3:143-151. [ Show Abstract ]

PURPOSE: The purpose of this study was to investigate the impact of using a rewetting drop (RWD) containing surface active agents (OPTI-FREE RepleniSH; Alcon, Fort Worth, TX) on the clinical performance and protein deposition when using a continuous-wear (CW) silicone hydrogel (SH) contact lens. METHODS: Subjects wore lotrafilcon A SH lenses on a 30-day CW basis for two consecutive 1-month periods while inserting either 0.9% unpreserved unit-dose saline (control) or multidose OPTI-FREE RepleniSH (test RWD). Subjective comfort and symptoms were assessed after 2 and 4 weeks with each product. After 1 month of wear with each product, lenses were collected and analyzed in the laboratory for total protein, total lysozyme, and percentage of denatured lysozyme. RESULTS: Symptoms of dryness and comfort varied across the day regardless of drop type (p < 0.001) with dryness being maximal on waking, least in the middle of the day, and increased towards the evening. The test RWD provided greater comfort on insertion (p = 0.02), better visual quality (p < 0.01), and less mucous discharge on waking (p = 0.02) than the control product. Lysozyme deposition was significantly reduced after the use of the test RWD as compared to saline (0.73 +/- 0.5 microg/lens vs. 1.14 +/- 0.7 microg/lens; p < 0.001) as was total protein deposition (1.17 +/- 0.7 microg/lens vs. 1.86 +/- 0.8 microg/lens; p < 0.001). Lysozyme denaturation was also reduced with the use of the test RWD compared with the control (76 +/- 10% vs. 85 +/- 7%; p < 0.01). CONCLUSIONS: The use of a RWD containing surface active agents provided greater subjective satisfaction, reduced lysozyme and total protein deposition, and reduced denatured lysozyme than a RWD containing saline alone.

Subbaraman,L. N., Glasier,M. -A, Senchyna,M., Sheardown,H., Jones,L. Kinetics of in vitro lysozyme deposition on silicone hydrogel, PMMA, and FDA groups I, II, and IV contact lens materials. Current eye research 2006;31,10:787-796. [ Show Abstract ]

We sought to compare the kinetics of in vitro lysozyme deposition on silicone hydrogel (SH), polymethyl methacrylate (PMMA), and FDA groups I, II, and IV contact lenses. Lenses were incubated in 125I-labeled lysozyme for time periods ranging from 1 hr to 28 days, and radioactive counts were determined. SH lenses and PMMA deposited less lysozyme than conventional hydrogel lenses (p < 0.05). Lysozyme accumulation on group IV lenses reached a maximum on the seventh day and then plateaued, whereas on groups I, II, and SH lenses, deposition continued to increase across all time periods, reiterating that kinetics of lysozyme deposition is highly material dependent.

Teichroeb,J. H., Forrest,J. A., Ngai,V., Jones,L. W. Anomalous thermal denaturing of proteins adsorbed to nanoparticles. European Physical Journal E 2006;21,1:19-24. [ Show Abstract ]

We have used localized surface plasmon resonance (LSPR) to monitor the structural changes that accompany thermal denaturing of bovine serum albumin (BSA) adsorbed onto gold nanospheres of size 5nm-60nm. The effect of the protein on the LSPR was monitored by visible extinction spectroscopy. The position of the resonance is affected by the conformation of the adsorbed protein layer, and as such can be used as a very sensitive probe of thermal denaturing that is specific to the adsorbed protein. The results are compared to detailed calculations and show that full calculations can lead to significant increases in knowledge where gold nanospheres are used as biosensors. Thermal denaturing on spheres with diameter > 20 nm show strong similarity to bulk calorimetric studies of BSA in solution. BSA adsorbed on nanospheres with d ≤ 15nm shows a qualitative difference in behavior, suggesting a sensitivity of denaturing characteristics on local surface curvature. This may have important implications for other protein-nanoparticle interactions. © EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2006.

2005

Srinivasan,S., Joyce,E., Jones,L. W., Senchyna,M. Subconjunctival cyst-like formations following impression cytology. Contact Lens and Anterior Eye 2005;28,4:181-184. [ Show Abstract ]

Purpose: To report a case of an unusual adverse event subsequent to undertaking Conjunctival Impression Cytology (CIC). Methods: CIC was un dertaken on a 54-year-old healthy Caucasian female, using a 10 mm Millipore™ membrane on the bulbar conjunctiva. Prior to the CIC procedure, two drops of topical proparacaine (Alcaine®) were instilled and following the procedure two drops of artificial tears (GenTeal®) were administered. Results: The subject reported excessive bulbar conjunctival hyperaemia in the left eye 5 min postprocedure, with no marked pain or discomfort. Slitlamp biomicroscopic evaluation revealed several "bubbles" or cystic formations trapped underneath the conjunctival tissue, in association with moderate to severe bulbar conjunctival redness. These cysts began to regress fairly rapidly and completely disappeared within 1 h. Conclusion: CIC is a useful tool for studying the ocular surface; however, care should be taken while performing this mildly invasive procedure. This is the first report of bubble formation in the conjunctiva following CIC. Subjects should be advised about the short term redness and discomfort that could occur following CIC. © 2005 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Subbaraman,L. N., Glasier,M. -A, Senchyna,M., Jones,L. Stabilization of lysozyme mass extracted from lotrafilcon silicone hydrogel contact lenses. Optometry and Vision Science 2005;82,3:209-214. [ Show Abstract ]

PURPOSE: Lysozyme deposits extracted from lotrafilcon silicone hydrogel (SH) contact lens materials demonstrate a loss in total mass as a function of storage time when assessed by Western blotting. This loss represents a potential source of error when quantifying total lysozyme deposition on SH lenses. The purpose of this study was to devise a method whereby lysozyme mass would be preserved over time to allow for its accurate quantitation after its removal from SH lenses. METHODS: Lysozyme deposits from 12 human worn lotrafilcon lenses were extracted using a 50:50 mixture of 0.2% trifluoroacetic acid and acetonitrile. Extracts were lyophilized to dryness, then resuspended in either reconstitution buffer (10 mM Tris-HCl, 1 mM EDTA) or modified reconstitution buffer (reconstitution buffer + 0.9% saline). BIOSTAB Biomolecule Storage Solution (Sigma-Aldrich) was added to one half of the samples from each buffer group. One microliter of each of the samples was immediately subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blotting, whereas the remaining volume was aliquoted and stored at -20 degrees C or -70 degrees C and subjected to the same procedures after 48 h of storage. Comparison of lysozyme band intensity in stored vs. fresh samples enabled calculation of percentage mass loss of lysozyme. RESULTS: Samples stored at -20 degrees C in reconstitution buffer with no BIOSTAB demonstrated a 33% loss in mass over 48 h of storage. Identical samples stored at -70 degrees C in modified reconstitution buffer with BIOSTAB added demonstrated <1% loss in mass. Statistical analysis indicated that buffer composition (p < 0.001), storage temperature (p = 0.04), and addition of BIOSTAB (p < 0.001) were all important in controlling loss of mass over time. CONCLUSION: We have optimized a procedure whereby the extracted mass of lysozyme deposits found on lotrafilcon SH lenses can be preserved, thus enabling accurate quantitation after extraction and resuspension.

2004

Haque,S., Fonn,D., Simpson,T., Jones,L. Corneal and epithelial thickness changes after 4 weeks of overnight corneal refractive therapy lens wear, measured with optical coherence tomography. Eye and Contact Lens 2004;30,4:189-193. [ Show Abstract ]

Purpose. To investigate thickness changes of the total cornea and epithelium across the horizontal corneal meridian after 4 weeks of overnight corneal refractive therapy (CRT) rigid contact lens (Paragon Vision Sciences, Mesa, AZ) wear. Methods. Thirty subjects were fitted with CRT contact lenses (Dk/t = 67), which were worn overnight for 4 weeks. Corneal thickness was measured at nine locations along the horizontal meridian by using optical coherence tomography (OCT) before lens insertion in the evening. Corneal thickness was measured the next morning immediately after lens removal and 1, 3, 7, and 14 hours later. This was repeated on days 4, 10, and 28 of the study and then 3 days after discontinuing lens wear. Results. Twenty-three subjects completed the study. At lens removal on day 1, the central and paracentral cornea swelled by 4.9% and 6.2%, respectively (both P = 0.000). The central epithelium thinned by 7.3%, and the mid peripheral epithelium thickened by 13% (both P = 0.000). Corneal swelling recovered throughout the day, with most of the deswelling taking place within the first 3 hours after lens removal. Maximal central epithelial thinning reached 13.5% by day 4. Three days after the study completion, corneal and epithelial thickness had recovered to baseline values. Conclusions. This study shows that CRT lenses induce differential overnight swelling across the cornea, with rapid deswelling during the day. Central epithelial thinning and paracentral thickening occurs, with recovery 3 days after discontinuation of lens wear. © 2004 Contact Lens Association of Ophthalmologists, Inc.

Karlgard,C. C. S., Sarkar,D. K., Jones,L. W., Moresoli,C., Leung,K. T. Drying methods for XPS analysis of PureVision™, Focus® Night&Day™ and conventional hydrogel contact lenses. Applied Surface Science 2004;230,1-4:106-114. [ Show Abstract ]

The surface composition of hydrogel contact lenses that contain silicon-based monomers, PureVision™ (balafilcon A) and Focus® Night&Day™ (lotrafilcon A), were investigated by X-ray photoelectron spectroscopy (XPS). Conventional and daily disposable hydrogel lenses based on hydroxyethyl methacrylate (HEMA) were also studied, with the commonly prescribed 1-day Acuvue® lens (etafilcon A) used as a control. All the lenses were pre-washed and dehydrated by three different methods, including drying in air, drying in nitrogen or freezing with subsequent freeze-drying, before the XPS analysis. The lenses dried in air had more impurities on the surface, and the lenses that were freeze-dried lost transparency, suggesting that drying lenses in nitrogen is the preferred preparation method for XPS analysis. Surface compositions for all lens materials were obtained and this data can be used as a control/base-value for future analysis of the interactions of soft contact lens materials with chemicals such as drugs or tear components. © 2004 Elsevier B.V. All rights reserved.

Sorbara,L., Simpson,T., Vaccari,S., Jones,L., Fonn,D. Tear turnover rate is reduced in patients with symptomatic dry eye. Contact Lens and Anterior Eye 2004;27,1:15-20. [ Show Abstract ]

Purpose: Tear turnover rate (TTR) is defined as the percent decrease of fluorescein concentration in the tears per minute after the instillation of fluorescein. The purpose of this study was to examine differences in TTR in a sample with symptoms of dry eye and an asymptomatic control sample using the Fluorotron Master™ Fluorophotometer. Methods: TTR was measured using the OcuMetrics Fluorotron Master™. It measures the decay of the fluorescence of high molecular weight fluorescein FITC Dextran instilled into the tear film. Twenty participants (post-menopausal women) were enrolled in the study (10 asymptomatic (age 64.7±6.99) and 10 symptomatic (age 61.5±7.98)). Participants were grouped according to either a positive (symptomatic) or negative (asymptomatic) McMonnies Dry Eye Questionnaire, i.e., an indication of self-reported ocular dryness and the use of rewetting/lubricating drops (questions 4 and 5). TTR was measured in the afternoon only. Measurements were made on the right eye with a controlled blink rate (15 blinks/min), for up to 30 min, post-insertion of 2 μl of 2% FITC Dextran (MW 9500). The scan data were used to construct a graph of log fluorescein concentration (ng/ml) as a function of time and the TTR calculated (%/min=(1-ln (slope))×100). Results: There was a significant difference in the TTR between symptomatic and asymptomatic subjects. Mean TTR (symptomatic) was 4.89±2.74%/min (range, 2.04-11.81) and mean TTR (asymptomatic) was 11.85±3.31%/min (range, 5.76-16.45) (P<0.0001). Conclusions: Fluorophotometry may be used to demonstrate differences in the tear turnover rate in this post-menopausal group of women, with patients experiencing symptoms of dry eye having a lower TTR than the normals. © 2003 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

2003

Wang,J., Fonn,D., Simpson,T. L., Jones,L. Precorneal and pre- and postlens tear film thickness measured indirectly with optical coherence tomography. Investigative Ophthalmology and Visual Science 2003;44,6:2524-2528. [ Show Abstract ]

PURPOSE. To demonstrate the feasibility of indirectly measuring the precorneal tear film thickness and pre- and postlens tear film (PLTF) thickness using optical coherence tomography (OCT). METHODS. Central corneal thickness (C1) which includes the tear film (T) of both eyes of 40 non-contact lens wearers was measured using OCT after calibration. The mean age of the 40 subjects was 31.2 ± 9.3 years with a mean horizontal K-reading of 7.87 mm. Rigid contact lenses with base curves 0.3- to 0.5-mm steeper than the flattest K of the eye were fitted to measure real corneal thickness (C2), independently of the postlens tear film. T was calculated by T = C1 - C2. To measure pre- and postlens tear film thickness, Focus Night & Day and Acuvue lenses (Vistakon, Johnson & Johnson Vision Care, Jacksonville, FL) were fitted on both eyes. Central soft lens thickness (L1), which includes the prelens tear film (P), was measured by OCT in situ and in saline in a wet cell (L2). P was calculated by P = L1 - L2. Thickness of the central cornea plus the postlens tear film (C3) was measured during lens wearing. Postlens tear film (PLTF) was calculated by PLTF = C3 - C2. RESULTS. The mean ± SD precorneal tear film thickness was 3.3 ± 1.5 μm (range, 0-6.9) before lens insertion and 4.7 ± 2.3 μm (range, 0.7-11.0) after lens fitting, which was significantly thicker (paired t-test: P < 0.01). The prelens tear film thickness was 3.9 ± 2.6 and 3.6 ± 2.1 μm (mean ± SD; paired t-test: P = 0.52) and the postlens tear film thickness was 4.5 ± 2.3 and 4.7 ± 3.1 μm (paired t-test: P = 0.08) on and under Focus Night & Day and Acuvue lenses, respectively. Post hoc tests showed that precorneal (baseline) and prelens tear films were equivalent, and each was different (thinner; Tukey honestly significant difference P < 0.05) from the postlens tear film. CONCLUSIONS. OCT can noninvasively measure the thickness of the precorneal and prelens tear film as well as the postlens tear film. The thickness of the normal precorneal tear film is approximately 3 μm and becomes thicker after lens fitting. The postlens tear film is thicker than the precorneal and prelens tear films with soft contact lenses. The thickness of both preand postlens tear films appears to be independent of the investigated lens types.

Jones,L., Senchyna,M., Glasier,M. A., Schickler,J., Forbes,I., Louie,D., May,C. Lysozyme and lipid deposition on silicone hydrogel contact lens materials.. Eye Contact Lens 2003;29,1 Suppl:S75-79; discussion S83-84, S192-194. [ Show Abstract ]

PURPOSE: We sought to determine whether there were differences in lysozyme (quantity and conformation) and lipid deposition on in vivo worn conventional (etafilcon) and silicone hydrogel (balafilcon and lotrafilcon) contact lenses. METHODS: After extraction, lysozyme concentration in each extract was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Lysozyme activity was determined by the rate of lysis of Micrococcis lysodeikticus cells. Lipid deposition was determined by high-performance liquid chromatography. RESULTS: Lysozyme deposition on etafilcon lenses was significantly greater than that measured on silicone hydrogel (SH) lenses (985 microg per lens versus 10 and 3 microg per lens for balafilcon and lotrafilcon materials, respectively; P<0.001). The degree to which lysozyme was denatured was influenced by the lens material, with the lowest degree of denaturation (22%) seen on the conventional lens material, as compared with 50% for balafilcon and 80% for lotrafilcon (P<0.001). Lipid deposition was greatest on the SH materials, with up to 600 microg per lens of certain lipid classes being deposited on balafilcon, as compared with 20 microg per lens on etafilcon (P<0.001). CONCLUSION: The quantity and conformation of lysozyme and the quantity of lipid deposited on hydrogel contact lenses is significantly influenced by the composition of the lens material. SH contact lens materials deposit low levels of lysozyme and high levels of lipid deposition compared with ionic contact lens materials. Although SH materials deposit only small amounts of lysozyme, the degree of lysozyme denaturation that occurs is higher relative to that seen on ionic lens materials.

Karlgard,C. C. S., Jones,L. W., Moresoli,C. Ciprofloxacin interaction with silicon-based and conventional hydrogel contact lenses. Eye and Contact Lens 2003;29,2:83-89. [ Show Abstract ]

Purpose. Hydrogel contact lenses can be used as bandage lenses to protect the corneal surface after injury. The use of novel silicon-based hydrogel lens materials as bandage lenses has not gained widespread acceptance. As a first step toward advocating their usefulness as bandage lenses, their interaction with ocular pharmaceuticals must be understood because topical agents are often administered in conjunction with bandage lenses. Methods. The in vitro uptake and release of ciprofloxacin from silicone-based hydrogel (SH) and conventional pHEMA-based (CH) hydrogel contact lenses was examined by spectrophotometric evaluation of the drug concentration in saline solution. Results. The hydrogel contact lenses tested showed similar drug uptake (average 1800 μg/lens) but different levels of drug release. Multiphoton laser microscopy indicated that ciprofloxacin was distributed throughout the lens thickness, with higher levels of drug at the surface owing to drug precipitation. The drug adsorption onto the lenses was partially reversible. The SH lenses released a lower amount of drug than CH lenses (72 vs. 168 μg/lens). Ionic lenses released less drug than non-ionic lenses (127 vs. 151 μg/lens). Conclusions. The differences in ciprofloxacin uptake and release between SH and CH materials may not be clinically significant because the amount of drug released from all lenses would be above the MIC90 of ciprofloxacin for common ocular pathogens. These results indicate that material properties have a significant impact on drug-lens interactions. © 2003 Contact Lens Association of Ophthalmologists, Inc.

Karlgard,C. C. S., Wong,N. S., Jones,L. W., Moresoli,C. In vitro uptake and release studies of ocular pharmaceutical agents by silicon-containing and p-HEMA hydrogel contact lens materials. International journal of pharmaceutics 2003;257,1-2:141-151. [ Show Abstract ]

The in vitro uptake and release behaviour of cromolyn sodium, ketotifen fumarate, ketorolac tromethamine and dexamethasone sodium phosphate with silicon-containing (lotrafilcon and balafilcon) and p-HEMA-containing (etafilcon, alphafilcon, polymacon, vifilcon and omafilcon) hydrogel contact lenses indicated that both drug and material affected the uptake and release behaviour. Rapid uptake and release (within 50min) was observed for all drugs except ketotifen fumarate which was more gradual taking approximately 5h. Furthermore, the maximum uptake differed significantly between drugs and materials. The highest average uptake (7879±684μg/lens) was cromolyn sodium and the lowest average uptake (67±13μg/lens) was dexamethasone sodium phosphate. Partial release of the drug taken up was observed for all drugs except dexamethasone sodium phosphate where no release was detected. Sustained release was demonstrated only by ketotifen fumarate. Drug uptake/release appeared to be a function of lens material ionicity, water and silicon content. The silicon-containing materials released less drug than the p-HEMA-containing materials. The lotrafilcon material demonstrated less interactions with the drugs than the balafilcon material which can be explained by their different bulk composition and surface treatment. © 2003 Elsevier Science B.V. All rights reserved.

2002

Wang,J., Fonn,D., Simpson,T. L., Jones,L. Relation between optical coherence tomography and optical pachymetry measurements of corneal swelling induced by hypoxia. American Journal of Ophthalmology 2002;134,1:93-98. [ Show Abstract ]

PURPOSE: To determine the relation between optical coherence tomography (OCT) and optical pachymetry (OP) measurements of corneal swelling induced by hypoxia. DESIGN: Experimental study. METHODS: One randomly selected eye of 20 noncontact lens wearers (10 males and 10 females, age 35.6 ± 9.6 years) was patched during 3 hours of soft contact lens (SCL) wear while the contralateral eye acted as control. Central corneal thickness of both eyes was measured before and after SCL wear using OCT and OP in randomized order. RESULTS: Baseline central corneal thickness was 523.6 ± 33.0 μm (mean ± standard deviation [SD]) measured with OCT and 490.6 ± 25.5 μm with OP. Immediately after contact lens removal, corneal thickness measured with OCT increased by 13.8 ± 2.3% compared with 12.1 ± 1.8% (paired t test: P < .001) measured with OP. Thereafter, corneal thickness decreased at the rate of 5.6% per hour for OCT and 5.4% per hour for OP. The difference in thickness between instruments before lens insertion, which was 33 μm compared with the difference after lens removal (edematous cornea), which ranged from 46 to 41 μm. The difference between instruments decreased during the corneal deswelling period after lens removal. The correlation coefficient between OCT and OP was 0.914 before lens insertion and 0.932 after lens removal. CONCLUSION: This study has demonstrated the difference of corneal thickness measured with OCT and OP. Although both instruments are correlated highly in all conditions tested, OCT may overestimate corneal thickness in normal and edematous corneas. © 2002 by Elsevier Science Inc. All rights reserved.

Wang,J., Fonn,D., Simpson,T. L., Jones,L. The measurement of corneal epithelial thickness in response to hypoxia using optical coherence tomography. American Journal of Ophthalmology 2002;133,3:315-319. [ Show Abstract ]

PURPOSE: To determine if corneal epithelial thickness increases in association with corneal edema induced by wearing soft contact lenses during eye closure. DESIGN: Experimental study. METHODS: One eye (randomly selected) of twenty noncontact lens wearers (10 males and 10 females, age 35.6 ± 9.6 years) was patched during 3 hours of soft contact lens (SCL) wear and the contralateral eye acted as a control. Corneal and epithelial thickness of both eyes was measured before and after SCL wear using optical coherence tomography (OCT). RESULTS: Immediately after contact lens removal, total corneal thickness was increased significantly by 13.8 ± 2.3% (mean ± SD) compared with baseline (P .05, paired t test). Immediately after contact lens removal, corneal epithelial thickness was increased by 1.7 ± 4.8%, but this change was not statistically significant (P > .05, paired t test). Following contact lens removal, epithelial thickness changed significantly (Repeated measure analysis of variance [Re-ANOVA]: F(7,133) = 4.91, pH-F < 0.001) over the next 100 minutes with thinning recorded at 60, 80, and 100 minutes (P < .05, paired t test). There was no significant change over time in epithelial thickness of the control eyes (Re-ANOVA: F(4, 76) = 0.91, pH-F = 0.464). CONCLUSION: OCT demonstrated that corneal epithelial thickness does not increase in response to hypoxia from SCL wear and eye closure, in contrast to a significant increase in total corneal thickness. © 2002 by Elsevier Science Inc. All rights reserved.

Jones,L., Macdougall,N., Sorbara,L. G. Asymptomatic corneal staining associated with the use of balafilcon silicone-hydrogel contact lenses disinfected with a polyaminopropyl biguanide-preserved care regimen. Optometry and Vision Science 2002;79,12:753-761. [ Show Abstract ]

PURPOSE: To compare subjective symptoms and signs in a group of individuals who wear silicone-hydrogel lenses on a daily wear basis while they sequentially used two differing care regimens. METHODS: Fifty adapted soft-lens wearers were fitted with a silicone-hydrogel lens material (PureVision, Bausch & Lomb). The lenses were worn on a daily wear basis for two consecutive 1-month periods, during which the subjects used either a Polyquad (polyquaternium-1) -based system or a polyaminopropyl biguanide (PHMB) -based system, using a double-masked, randomized, crossover experimental design. RESULTS: Significant levels of relatively asymptomatic corneal staining were observed when subjects used the PHMB-based system, with 37% of subjects demonstrating a level of staining consistent with a classical solution-based toxicity reaction. Only 2% of the subjects exhibited such staining when using the Polyquad-based system. These results were significantly different (p < 0.001). Significant symptoms were not correlated with the degree of staining, with no differences in lens comfort or overall preference being reported between the regimens (p = NS). The only statistically significant difference in symptoms related to minor differences in stinging after lens insertion being reported, with the Polyquad-based system demonstrating less stinging (p < 0.008). CONCLUSIONS: Practitioners who fit silicone-hydrogel contact lenses on a daily wear basis should be wary of the potential for certain PHMB-containing multipurpose care systems to invoke corneal staining. Switching to non-PHMB based regimens will eliminate this complication in most instances.

Jones,L., May,C., Nazar,L., Simpson,T. In vitro evaluation of the dehydration characteristics of silicone hydrogel and conventional hydrogel contact lens materials. Contact Lens and Anterior Eye 2002;25,3:147-156. [ Show Abstract ]

Purpose: This study investigated the in vitro dehydration performance of silicone hydrogel and conventional hydrogel contact lens materials. Methods: In vitro dehydration was assessed using a gravimetric method. The mass loss over time of Focus Night&Day, PureVision, Optima, Acuvue and Proclear Compatibles was measured as the ambient temperature increased from room temperature to 34°C under varying airflow and humidity conditions. Results: Dehydration data demonstrated a typical ogival form. The results were best fitted with a double exponential, non-linear regression model, which accounted for at least 99% of the variance. Regardless of material, increased airflow had a greater impact on dehydration rate than increased humidity (P < 0.05). Relative dehydration amounts were strongly correlated with initial water content (r2 = 0.92), with higher water content materials dehydrating to a greater extent. Conclusions: In vitro dehydration studies of conventional and novel silicone-containing hydrogel materials indicated that evaporation rates from materials are predominantly water content related, with only subtle differences between materials of similar water contents being seen. Environmental conditions have a significant impact on in vitro dehydration, with increased airflow having a greater impact than reduced humidity on increasing dehydration rates. In vitro dehydration is closely related to bulk water diffusion rates and, as a result of their low water content, silicone-containing hydrogel materials exhibit low levels of dehydration compared with high water content hydrogel contact lens materials. Further, in vivo studies are necessary to see if the in vitro dehydration behaviour of silicone hydrogel materials is predictive of in-eye performance. © 2002 British Contact Lens Association. Published by Elsevier Science Ltd. All rights reserved.

Mann,A. M., Jones,L. W., Tighe,B. J. The application of counter immunoelectrophoresis (CIE) in ocular protein studies. Part I: Time dependent deposition patterns of immunoregulatory proteins on anionic hydrogel contact lenses. Contact Lens and Anterior Eye 2002;25,2:73-80. [ Show Abstract ]

This paper focuses on the effects of wear regime on the deposition pattern of important immunoregulatory proteins on FDA Group IV etafilcon-A lenses. Specifically, the aim was to assess the extent to which the daily disposable wear modality produces a different deposition of proteins from the conventional daily wear regime which is coupled with cleaning and disinfection. Counter immunoelectrophoresis (CIE) was employed to detect individual proteins in lens extracts from individual patients and focused on the analysis of five proteins, IgA, IgG, lactoferrin, albumin and kininogen. Deposition was monitored as a function of time; significantly lower deposition was detected on the daily disposable lenses. cr 2002 British Contact Lens Association. Published by Elsevier Science Ltd. All rights reserved.

2001

Jones,L. W., Jones,D. A. Non-inflammatory corneal complications of contact lens wear. Contact Lens and Anterior Eye 2001;24,2:73-79. [ Show Abstract ]

Contact lenses can induce changes in the epithelium, stroma and endothelium of the cornea, all of which can be observed clinically using the slit-lamp biomicroscope. These complications include epithelial microcysts, vacuoles and staining, stromal oedema and vascularization, and endothelial polymegethism and blebs. Each complication can be attributed to one or more aetiological factors such as hypoxia, hypercapnia, tissue acidosis, trauma, hypersensitivity and toxicity. This review outlines the way in which these complications manifest clinically, and consideration is given to management strategies and likely prognoses. Early detection of these conditions and appropriate action can usually prevent more serious ocular complications.

Tonge,S., Jones,L., Goodall,S., Tighe,B. The ex vivo wettability of soft contact lenses. Current eye research 2001;23,1:51-59. [ Show Abstract ]

Purpose. To investigate the ex vivo wettability of Etafilcon A contact lenses over an eight hour period of wear and observe the influence of surfactant pre-treatment. Methods. Etafilcon A hydrogel lenses, comprising poly[2-hydroxyethyl methacrylate-co-methacrylic acid] and 58% water, were soaked for 12 hours in either 0.9% saline (control) or a 1% aqueous solution of poloxamine 1107 (treated). The advancing and receding contact angles were subsequently determined ex vivo after various periods of wear in six adapted contact lens wearers using a single-blind, randomised protocol. Contact angles were measured with a dynamic contact angle tensiometer, using the Wilhelmy plate technique. Patient comfort scores were recorded and the static surface tensions of the probe fluids assessed. Results. Control lenses exhibited no change in wetting angles over time, indicating a lack of surface modification by components within the tear film. Treated lenses exhibited a significantly reduced advancing angle (p > 0.001) and hysteresis angle (p < 0.001) when compared with control lenses. In addition, treated lenses were consistently rated as being more comfortable than control lenses (p = 0.04). Conclusions. This study has shown clearly that new Etafilcon A lenses do not exhibit significant changes in wettability during the initial four hour wearing period. Pre-treatment of such lenses with a polymeric surfactant results in wetting of the lenses due to the adsorption of surfactant. The surfactant is retained by the lens for at least eight hours of wear, resulting in significant improvements in subjective comfort, especially over the first 30 minutes of wear.

2000

Dumbleton,K., Jones,L., Chalmers,R., Williams-Lyn,D., Fonn,D. Clinical characterization of spherical post-lens debris associated with lotrafilcon high-DK silicone lenses. CLAO Journal 2000;26,4:186-192. [ Show Abstract ]

Purpose: Experience with high Dk silicone hydrogel lenses has revealed post-lens debris, which is characterized by the appearance of spherical, translucent particles referred to as 'mucin balls.' The objectives of this analysis were to characterize the presence of mucin balls, determine whether any ocular characteristic predicts the development of mucin ball debris, and determine whether there is any association between mucin balls and the ocular response to contact lens wear. Methods: Ninety-two subjects wore lotrafilcon A lenses on an extended wear basis for up to 30 nights and were followed for 6 months. Mucin balls were graded on a 0 to 4 scale at three visits. Subjective ratings and biomicroscopic appearance were recorded at all visits. Results: Mucin balls were observed in 70% of subjects at one or more visits, and 29% of subjects at all three visits. There was no change in the mean grade of mucin balls over time. Mucin balls were graded > 1 in 20% of eyes, > 2 in 6% of eyes, and > 3 in 2% of eyes. Subjects who exhibited mucin balls at each clinical visit had significantly steeper keratometry readings along the flatter meridian (44.3 D) than those who never exhibited mucin balls (42.9 D, P<0.0001). The percentage of subjects who 'never' use lubricating drops was higher in the subjects with mucin balls (P=0.0014). No association was found between mucin ball observation and biomicroscopic appearance, inflammatory responses, or subjective responses. Conclusions: The presence of mucin balls does not appear to be detrimental to contact lens wear. Eyes with steeper corneal curvature were significantly more likely to present with mucin ball debris, indicating they may be a function of lens fit. Clinical factors that may be modified in order to menage the more severe presentation of mucin balls are the use of lubricating drops and the number of nights extended wear schedule.

Pritchard,N., Jones,L., Dumbleton,K., Fonn,D. Epithelial inclusions in association with mucin ball development in high-oxygen permeability hydrogel lenses. Optometry and Vision Science 2000;77,2:68-72. [ Show Abstract ]

Debris trapped behind contact lenses may be associated with adverse reactions in extended wear. Although streaks and clumps of cellular material have been reported after overnight wear of conventional materials, recent experience with several high-oxygen permeability (Dk), silicone-containing hydrogel lenses indicates that certain participants are prone to the development of a unique back surface debris. This debris forms as spherical, translucent entities and results in depressions within the ocular surface after lens removal. Little information is known about these spherical bodies, particularly with respect to their composition and development. In this report, we provide photographic evidence of this debris (sometimes termed 'mucin balls' or 'lipid plugs'), discuss its differential diagnosis and describe a case in which material seems to be embedded in the epithelium as a direct consequence of their presence.

1999

Mathur,A., Jones,L., Sorbara,L. Use of reverse geometry rigid gas permeable contact lenses in the management of the postradial keratotomy patient: Review and case report. International Contact Lens Clinic 1999;26,5:121. [ Show Abstract ]

Radial keratotomy (RK) is a well-known procedure for reducing myopia. However, the complications associated with the procedure and the development of newer technologies, such as photorefractive keratectomy and laser-assisted in situ keratomileusis, has resulted in the technique of RK falling out of favor. A number of patients who received RK during the 1980s are now experiencing a shift in their prescription and are presenting to primary care practitioners for contact lens fitting. These patients pose a significant challenge to the contact lens practitioner, and novel methods frequently are required to fit corneas that exhibit such abnormal topography. This article reviews the potential problems associated with fitting patients who have received RK and describes a case in which a novel lens design was used to achieve a successful lens fit.

Abstracts

2016

Phan C, Bajgrowicz M, Subbaraman L, Jones L. Release of moxifloxacin from daily disposable contact lenses using an in vitro eye model: Impact of artificial tear fluid composition and mechanical rubbing. Invest Ophthalmol Vis Sci 2016;57: E-abstract 1474. [ PDF ]

Walther H, Phan C, Subbaraman L, Jones L. Cholesterol Penetration into Daily Disposable Contact Lenses Using a Novel In Vitro Eye-Blink Model. Invest Ophthalmol Vis Sci 2016;57: E-abstract 1476. [ PDF ]

Ngo W, Jones L, Srinivasan S, Bitton E. Discomfort over Time Associated with various Ocular Demodex Treatment Products. Invest Ophthalmol Vis Sci 2016;57: E-abstract 2838. [ PDF ]

Liu S, Dozois M, Chang C, Hileeto D, Liang H, Reyad M, Boyd S, Jones L, Gu F. Mucoadhesive nanoparticle eye drop platform: tracking of ocular retention and treatment of experimental dry eye. Invest Ophthalmol Vis Sci 2016;57: E-abstract 3990.

Muntz A, Subbaraman L, Jones L. Is there an association between lid wiper epitheliopathy, lens type and contact lens discomfort?. Optom Vis Sci 2016;93: E-abstract 160047.

Subbaraman L, Omali N, Lada M, Canavan K, Fadli Z, Jones L. An in-vitro lipid uptake model to predict ex-vivo lipid depostion on worn silicone hydrogel contact lenses. Optom Vis Sci 2016;93: E-abstract 160099.

Qiao H, Phan C-M, Walther H, Subbaraman L, Jones L. Localizing lysozyme deposition on contact lenses using a novel in vitro eye model. Optom Vis Sci 2016;93: E-abstract 160100.

Walther H, Phan C-M, Qiao H, Liu Y, Subbaraman L, Jones L. In vitro eye model to simulate the impact of blinking on contact lens deposition and drug delivery. Optom Vis Sci 2016;93: E-abstract 160101.

Ngo W, Srinivasan S, Jones L. Comparison of dry eye tests between symptomatic and asymptomatic age-matched females. Optom Vis Sci 2016;93: E-abstract 165089. [ PDF ]

Phan C-M, Walther H, Riederer D, Smith R, Subbaraman L, Jones L. Determination of the release of wetting agents from nelfilcon a using a novel in vitro eye model. Optom Vis Sci 2016;93: E-abstract 165114. [ PDF ]

Heynen M, Qiao H, Subbaraman L, Scales C, Riederer D, Fadli Z, Jones L. Location of non-polar lipids in monthly replacement silicone hydrogel contact lens materials. Optom Vis Sci 2016;93: E-abstract 166116. [ PDF ]

Subbaraman L, Suko A, Omali N, Riederer D, Scales C, Fadli Z, Jones L. Polar and non-polar lipid deposition on monthly replacement contact lens materials. Optom Vis Sci 2016;93: E-abstract 165119.

Schulze M, Wong A, Haider S, Ebare K, Fadli Z, Coles-Brennan C, Jones L. Blink rate in silicone hydrogel contact lens wearers during digital device use. Optom Vis Sci 2016;93: E-abstract 165122. [ PDF ]

Moezzi A, Varikooty J, Luensmann D, Ng A, Schulze M, Karkkainen T, Xu J, Jones L. Open-eye clinical performance of etafilcon a multifocal daily disposable hydrogel contact lenses compared to habitual silicone hydrogel lens wear. Optom Vis Sci 2016;93: E-abstract 165259. [ PDF ]

Chamberlain P, Back A, Jones L, Logan N, Peixoto-de-Matos S, Mei Saw S, Young G. Parental perspectives on their child wearing daily disposable soft contact lenses in a multicenter clinical study. Optom Vis Sci 2016;93: E-abstract 165325.

Yang M, Luensmann D, Fonn D, Woods J, Gordon K, Jones L, Jones D. Myopia prevalence in canadian school children. Optom Vis Sci 2016;93: E-abstract 165328. [ PDF ]

Mohammadi S, Jones L, Gorbet M. Ocular drug release models: comparisons between in vitro cell, dynamic release, and fixed volume models. 10th World Biomaterials Congress, Montreal, 2016.

Jones L. Management and therapy of dry eye. TFOS conference, Montpelier, France, 2016.

Jones L. Tear film components and their impact on contact lens wear. Japanese Contact Lens Society conference, Tokyo, 2016.

Jones L, Varikooty J, Schulze M, Keir N. Assessment of contact lens comfort: Single report scores vs cumulative comfort. Asian Cornea and Contact Lens Conference, Hong Kong, 2016.

Stahl U, Keir N, Guthrie S, Jones L. Effect of monocular lens wear on ocular comfort. TFOS conference, Montpelier, France, 2016.

Subbaraman L, Omali N, Lada M, Canavan K, Fadli Z, Jones L. An in-vitro lipid uptake model to predict ex-vivo lipid deposition on worn silicone hydrogel contact lenses. TFOS conference, Montpelier, France, 2016.

Jones L, Guthrie S, Dumbleton K. Is there a relationship between care system and compliance?. Asian Cornea and Contact lens Conference, Hong Kong, 2016. [ PDF ]

2015

Ngo W, Caffery B, Srinivasan S, Jones L. Effect of Lid Debridement-Scaling on Dry Eye Signs and Symptoms in Sjogren’s Syndrome. Invest Ophthalmol Vis Sci 2015;56: E-abstract 2487. [ PDF ]

LeBlanc S, Verma M, Jones L, Gu F. Detecting bacteria colorimetrically on contact lens cases using immobilized gold nanoparticles. Invest Ophthalmol Vis Sci 2015;56: E-abstract 2268.

Phan C, Jones L, Subbaraman L, Bajgrowicz M. Release of fluconazole from daily disposable contact lenses using a novel in vitro eye model. Invest Ophthalmol Vis Sci 2015;56: E-abstract 3085.

McCanna D, Oh S, Seo J, Subbaraman L, Coles-Brennan C, Fadli Z, Jones L. Effect of Denatured Lysozyme on Human Corneal Epithelial Cells. Invest Ophthalmol Vis Sci 2015;56: E-abstract 3511. [ PDF ]

Subbaraman L, Ng A, Coles-Brennan C, Fadli Z, Jones L. Surface versus bulk activity of lysozyme deposited on soft contact lens materials. Invest Ophthalmol Vis Sci 2015;56: E-abstract 3168.

Ng AY, Keech A, Jones L. Detection of Tear Film Osmolarity Changes After Use of a Hydroxypropyl Guar-Based Lubricating Eye Drop. Invest Ophthalmol Vis Sci 2015;56: E-abstract 4429. [ PDF ]

Muntz A, vanDoorn K, Subbaraman L, Jones L. Impression cytology of the lid wiper area. Invest Ophthalmol Vis Sci 2015;56: E-abstract 4432. [ PDF ]

Srinivasan S, Ngo W, Jones L. The Relief of Dry Eye Signs and Symptoms Using a Combination of Lubricants, Lid Hygiene and Ocular Nutraceuticals. Invest Ophthalmol Vis Sci 2015;56: E-abstract 4465. [ PDF ]

Liu S, Dozois M, Ng D, Chang C, Hileeto D, Jones L, Gu F. Weekly dosing regimen of eye drop formulations delivered through mucoadhesive nanoparticles enhances treatment of experimental dry eye. Invest Ophthalmol Vis Sci 2015;56: E-abstract 5036.

Schulze M, Srinivasan S, Hickson-Curran S, Toubouti Y, Cox S, Mirza A, Nichols J, Morgan P, Jones L. Comparisons between Age, Gender, Lens Type and Lid Wiper Epitheliopathy with Soft Contact Lens Comfort. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6069. [ PDF ]

Bajgrowicz M, Phan C, Subbaraman L, Jones L. Release of ciprofloxacin and moxifloxacin from daily disposable contact lenses using an in vitro eye model. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6085. [ PDF ]

Dantam J, Heynen M, Dominici C, Subbaraman L, Coles-Brennan C, Fadli Z, Jones L. Qualitative asymmetric mapping of lysozyme deposited on various contact lens materials using confocal laser scanning microscopy. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6091. [ PDF ]

Walther H, Subbaraman L, Jones L. Novel in vitro method to determine pre-lens tear break up time of hydrogel and silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6105. [ PDF ]

Keir N, Srinivasan S, Ngo W, Chamberlain P, Feng W, Jones L, McNally J. Impact of time of day and length of wear on contact lens discomfort. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6107.

Babaei Omali N, Subbaraman L, Coles-Brennan, Fadli Z, Jones L. Selective uptake of lysozyme by various hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6109. [ PDF ]

vanDoorn K, Subbaraman L, Lemp J, Maissa C, Jones L. A device to model pollen deposition on contact lenses. Invest Ophthalmol Vis Sci 2015;56: E-abstract 6112. [ PDF ]

Guthrie S, Dumbleton K, Jones L. Is there a relationship between care system and compliance?. BCLA Clinical Conference and Exhibition, 2015. [ PDF ]

vanDoorn K, Subbaraman L, Lemp J, Maissa C, Jones L. Design and validation of a device for modeling pollen adhesion to contact lenses. BCLA Clinical Conference and Exhibition, 2015. [ PDF ]

Subbaraman L, McCanna D, Oh S, Ng A, Coles-Brennan C, Fadli Z, Jones L. Lysozyme activity on contact lenses and the impact of denatured lysozyme on human corneal epithelial cells. BCLA Clinical Conference and Exhibition, 2015. [ PDF ]

Jones L, Babaei Omali N, Heynen M, Coles-Brennan C, Fadli Z, Subbaraman L. Determining qualitative and quantitative uptake of lysozyme by various contact lens materials. BCLA Clinical Conference and Exhibition, 2015. [ PDF ]

Schulze M, Luensmann D, Ng AY, Panjwani F, Srinivasan S, Jones L. The relationship between the positioning of multifocal contact lens optics and satisfaction with vision. Optom Vis Sci 2015;92: E-abstract 155256. [ PDF ]

Guthrie S, Woods J, Dumbleton K, Fonn D, Jones L. Contact lens discomfort management strategies of ECPs. Optom Vis Sci 2015;92: E-abstract 155050. [ PDF ]

vanDoorn K, Subbaraman L, Lemp J, Maissa C, Jones L. Reversibility of pollen adhesion to contact lenses. Optom Vis Sci 2015;92: E-abstract 150025.

Panjwani F, Papinski D, Woods J, Jones L. In-vivo dehydration of omafilcon A and delefilcon A. Optom Vis Sci 2015;92: E-abstract 155048. [ PDF ]

Panjwani F, Papinski D, Varikooty J, Woods J, Jones L. In-vivo dehydration of stenfilcon A and delefilcon A silicone hydrogel materials. Optom Vis Sci 2015;92: E-abstract 155262. [ PDF ]

Ngo W, Srinivasan S, Jones L, Bitton E. Enhancement of Clinical Observation of Demodex Folliculorum. Optom Vis Sci 2015;92: E-abstract 155233. [ PDF ]

McCabe K, Piper S, Jones L, Papinski D, Fadli Z. In-vitro bacterial adhesion to silicone hydrogel contact lenses: Does a surface coating inhibit bacterial adhesion?. Optom Vis Sci 2015;92: E-abstract 155249.

Bitton E, Kronish S, Bouchard J-F, Jones L. The impact of hand rinsing time on soap residue left on the surface of silicone hydrogel CL. Optom Vis Sci 2015;92: E-Abstract 155255.

Subbaraman L, Heynen M, McCanna D, Omali N, Jansen M, Fadli Z, Toubouti Y, Coles-Brennan C, Jones L . Impact of pigment presence in etafilcon A on in vitro interaction of lysozyme and impact on inflammatory biomarker release. Optom Vis Sci 2015;92: E-abstract 150097.

McCabe K, Piper S, Jones L, Papinski D, Fadli Z. Bacterial Adhesion to Silicone Hydrogel and Conventional Hydrogel Lenses. Optom Vis Sci 2015;92: E-abstract 150026.

Ngo W, Srinivasan S, Jones L. The impact of an Eyelid Warming Device in the Management of Meibomian Gland Dysfunction. Optom Vis Sci 2015;92: E-abstract 150013.

2014

McCanna D,Liu L, Seo J, Subbaraman L, Jones L. Assessment of the growth of Stenotrophomonas maltophilia, Elizabethkingia meningoseptica and Delftia acidovorans in contact lens cases and on recovery media. Invest Ophthalmol Vis Sci 2014;55: E-abstract 6051.

Heynen M, Trieu D, Lorentz H, Jones L. Comparing and optimizing cholesterol extraction from hydrogel and silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2014;55: E-abstract 6058. [ PDF ]

Berntsen D, Hickson-Curran S, Jones L, Mathew J, Mirza A, Morgan P, Schulze M, Nichols J. Comparison of soft contact lens comfort using three contact lens materials and four contact lens solutions. Invest Ophthalmol Vis Sci 2014;55: E-abstract 863.

Dillehay S, Woods J, Situ P, Guthrie S, Paynor R, Griffin R, Tyson M, Jones L. Comparison of Three Power Levels of A Novel Soft Contact Lens Optical Design to Reduce Suspected Risk Factors for the Progression of Juvenile Onset Myopia. Invest Ophthalmol Vis Sci 2014;55: E-abstract 3637.

Srinivasan S, Schulze M, Hickson-Curran S, Berntsen D, Howarth G, Nichols J, Morgan P, Jones L. Comparison of upper lid margin staining with different soft contact lens materials and care product combinations. Invest Ophthalmol Vis Sci 2014;55: E-abstract 4673. [ PDF ]

Phan C, Subbaraman L, Jones L. Delivery of natamycin using cyclodextrin functionalized contact lenses. Invest Ophthalmol Vis Sci 2014;55: E-abstract 4643. [ PDF ]

Payor R, Woods J, Fonn D, Situ P, Dillehay S, Griffin R, Tyson M, Jones L. Feasibility Testing of a Novel Soft Contact Lens Optical Design to Reduce Suspected Risk Factors for the Progression of Juvenile Onset Myopia. Invest Ophthalmol Vis Sci 2014;55: E-abstract 3638.

Verma M, Chen P, Jones L, Gu F. Gold nanostars for the colorimetric detection of emerging bacterial contaminants that affect contact lens wearers. Invest Ophthalmol Vis Sci 2014;55: E-abstract 2158.

Walther H, Subbaraman L, Wettig S, Jones L. In vitro surface pressure measurements of various tear film lipids. Invest Ophthalmol Vis Sci 2014;55: E-abstract 43. [ PDF ]

Cheung S, Subbaraman L, Schmidt T, Jones L. Localization of full-length recombinant human proteoglycan 4 in commercial contact lenses using confocal microscopy. Invest Ophthalmol Vis Sci 2014;55: E-abstract 6059. [ PDF ]

Hui A, Jones L. Material Properties of Antibiotic Releasing Contact Lenses. Invest Ophthalmol Vis Sci 2014;55: E-abstract 4642. [ PDF ]

Dantam, McCanna D, Subbaraman L, Lakkis C, Morgan P, Nichols J, Jones L. Microbial contamination of contact lens storage cases with the use of different contact lens care solutions and lens materials. Invest Ophthalmol Vis Sci 2014;55: E-abstract 4675. [ PDF ]

Moezzi A, Varikooty J, Schulze M, Ngo W, Lorenz K, Jones L. Open Eye Corneal Swelling with 1-DAY ACUVUE® DEFINE™ and 1-DAY ACUVUE® DEFINE™ with Lacreon® compared to 1-DAY ACUVUE® MOIST®. Invest Ophthalmol Vis Sci 2014;55: E-abstract 4672. [ PDF ]

Liu S, Chang C, Verma M, Hileeto D, Muntz A, Stahl U, Woods J, Jones L, Gu F. Phenylboronic acid modified mucoadhesive nanoparticles facilitate weekly treatment of dry eye syndrome. Invest Ophthalmol Vis Sci 2014;55: E-abstract 2160.

Subbaraman L, McCanna D, Lorentz H, Soong F, Salapatek A, Jones L. Tear Cytokines in Non-Dry Eye and Dry Eye Participants After Exposure to a Low Humidity Environmental Exposure Chamber. Invest Ophthalmol Vis Sci 2014;55: E-abstract 3682.

Soong F, Lorentz H, Subbaraman L, Jones L, Salapatek A. The Controlled Low Humidity Environmental Exposure Chamber (LH-EEC) is a sensitive and specific tool for study of the Signs and Symptoms of Dry Eye (DE) versus Non-Dry Eye (NDE) Participant. Invest Ophthalmol Vis Sci 2014;55: E-abstract 2016.

Hall B, Jones L, Forrest J. The effect of lactoferrin on lysozyme deposition and activity on silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2014;55: E-abstract 6061. [ PDF ]

Jones L, Dantam J, McCanna D, Subbaraman L, Morgan P, Nichols J, Lakkis C. Impact of different contact lens care solutions and lens materials on contact lens storage case contamination. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Hui A, Willcox M, Jones L. Material properties and antimicrobial efficacy of novel antibacterial silicone hydrogel contact lenses. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Subbaraman L, Stahl U, Heynen M, Babaei Omali N, Canavan K, Jones L. Is there a difference in tear film and meibum composition in asymptomatic adapted contact lens and spectacle wearers?. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Varikooty J, Woods J, Jones L. Assessment of pre-lens tear film particle velocity measurements in participants wearing daily disposable silicone hydrogel lenses. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Schulze M, Subbaraman L, Babaei Omali N, Stahl U, Canavan K, Jones L. Is there a difference between clinical signs and symptoms in asymptomatic adapted contact lens and spectacle wearers?. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Schulze M, Srinivasan S, Hickson-Curran S, Bemsten D, Howarth G, Nichols J, Morgan P, Jones L. Upper lid margin staining with different soft contact lenses and lens care solution combinations. BCLA Clinical Conference and Exhibition, 2014. [ PDF ]

Jones L. Tune in or drop out. BCLA Clinical Conference and Exhibition, 2014.

Subbaraman L, Babaei Omali N, Heynen M, Lada M, Canavan K, Jones L. Could lipid deposition on contact lenses be beneficial?. BCLA Clinical Conference and Exhibition, 2014.

Stahl U, Luensmann D, Lemp J, Moezzi A, Schulze M, Varikooty, Dumbleton K, Jones L. Determination of higher order aberrations with two silicone hydrogel toric lenses. Optom Vis Sci 2014;91: E-abstract 145188. [ PDF ]

Luensmann D, Situ P, Fonn D, Jones L. Evaluation of the Performance of a New Silicone Hydrogel Color Contact Lens. Optom Vis Sci 2014;91: E-abstract 145179. [ PDF ]

Babaei Omali N, Subbaraman L, Heynen M, Thangavelu M, Dare E, Canavan K, Fadli Z, Jones L. Protein Deposition on Senofilcon A Contact Lenses in Symptomatic and Asymptomatic Lens Wearers. Optom Vis Sci 2014;91: E-abstract 145186. [ PDF ]

Babaei Omali N, Subbaraman L, Schulze M, Heynen M, Canavan K, Fadli Z, Jones L. Clinical Signs, Symptoms, Tear Film and Meibum Composition in Asymptomatic Senofilcon A Contact Lens and Spectacle Wearers. Optom Vis Sci 2014;91: E-abstract 145185. [ PDF ]

Schulze M, Luensmann D, Hickson-Curran S, Toubouti Y, Cox S, Plowright A, Nichols J, Morgan P, Jones L. Analysis of lid wiper epitheliopathy in habitual soft lens wearers. Optom Vis Sci 2014;91: E-abstract 140104.

Subbaraman L, Babaei Omali N, Heynen M, Lakkis C, Morgan P, Bertsen D, Nichols J, Jones L. Impact of different lens care solutions on protein deposition on various soft contact lenses: A multicenter study. Optom Vis Sci 2014;91: E-abstract 140057.

Hui A, Jones L. Uptake and release of atropine and pirenzepine from commercial hydrogel and silicone hydrogel contact lens materials. Optom Vis Sci 2014;91: E-abstract 140059.

Lorentz H, McCanna D, Subbaraman L, Jones L, Salapatek A, Soong F. Changes in cytokine expression for dry eye and non dry eye subjects exposed to a low humidity environmental exposure chamber. Optom Vis Sci 2014;91: E-abstract 140106.

Srinivasan S, Pucker A, Jones-Jordan L, Li W, Kwan J, Sickenberger W, Marx S, Lin M, Jones L. Meibomian Gland Atrophy Rate in Pre-presbyopic Contact Lens and Non-Contact Lens Wearers. Optom Vis Sci 2014;91: E-abstract 140081.

Cox S, Berntsen D, Chatterjee N, Hickson-Curran S, Jones L, Moezzi A, Morgan P, Nichols J. Eyelid margin characteristics associated with a large cohort of soft contact lens wearers. Optom Vis Sci 2014;91: E-abstract 140080.

Berntsen D, Varikooty J, Nichols J, Mathew J, Jones L, Morgan P, Smith S, Hickson-Curran S, Toubouti Y. Soft contact lens wear time and subjective dryness using different contact lens materials and solutions. Optom Vis Sci 2014;91: E-abstract 140085.

Pucker A, Kwan J, Jones-Jordan L, Jones L, Lin Meng, Marx S, Srinivasan S, Li W, Sickenberger W. Factors Associated with Meibomian Gland Atrophy in Daily Contact Lens Wearers. Optom Vis Sci 2014;91: E-abstract 140082.

2013

Stahl U, Keir N, Varikooty J, Nandakumar K, Keech A, Landers A, Jones L. The effect of recovery periods on end of day comfort. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5462.

Hall B, Phan C, Subbaraman L, Jones L. Forrest J. Direct comparison between in situ versus extraction techniques for measuring absorbed proteins: Application to lysozome deposited onto hydrogel contact lenses. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5467.

Samsom M, Chan A, Jones L, Schmidt T. PRG4 as a natural boundary lubricant for commerical silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5468.

Mohammadi S, Jones L, Gorbet M. Investigation of Latanoprost release from contact lens materials using in vitro cell models. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5472.

Patel P, Soong F, Varikooty J, Keir N, Jones L. Ocular signs and symptoms in contact lens wearers in a controlled low humidity environmental exposure chamber (LH-EEC), a natural provocation research model. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5473.

Jones L, Varikooty J, Keir N, Soong F, Patel P. The evaluation of lid wiper epitheliopathy in contact lens wearers in a controlled low humidity environmental exposure chamber. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5475.

Srinivasan S, Menzies K, Jones L. Infra-red imaging of meibomian glands & evaluation of the lipid layer in Sjogren’s syndrome patients. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 6012.

Dumbleton K, Richter D, Woods C, Aakre B, Plowright A, Jones L. A multi-country assessment of compliance with daily disposable contact lens wear. Contact Lens & Anterior Eye 2013;36,S2:e12.

Subbaraman L, Walther H, Kay L, Jones L. In vitro efficiency of contact lens care solutions in removing cholesterol deposits from silicone hydrogel contact lenses. Contact Lens & Anterior Eye 2013;36,S2:e41.

Jones L, Hui A. Release of ciprofloxacin and dexamethasone from commercial contact lens materials. Contact Lens & Anterior Eye 2013;36,S2:e38.

McCanna D, Jones L. The effect of contact lens solutions on membrane permeability of Staphylococcus aureus aggregates. Contact Lens & Anterior Eye 2013;36,S2:e40-e41.

Subbaraman L, Thangavelu M, McCanna, Jones L. A novel, multiplex electrochemiluminescent technique to quantify tear film inflammatory markers. Contact Lens & Anterior Eye 2013;36,S2:e45.

Srinivasan S, Menzies K, Jones L. Meibography and lipid layer evaluation in sjogern's syndrome patients. Contact Lens & Anterior Eye 2013;36,S2:e45.

Jones L. A report card on hydrogel contact lens materials: Where are we and what's new and novel?. Contact Lens & Anterior Eye 2013;36,S2:e9.

Dare E, Subbaraman L, Jones L. Effects of environmental changes on in vitro corneal epithelial wound healing. Contact Lens & Anterior Eye 2013;36,S2:e20.

Woods J, Subbaraman L, Jones L. In-vitro wettability of four silicone hydrogel lenses with differing surface properties. Contact Lens & Anterior Eye 2013;36,S2:e29.

Subbaraman L, Mistry R, Thangavelu M, Jones L. Quantification of lipocalin-1 in tears and contact lens deposits using a sandwich ELISA technique. Contact Lens & Anterior Eye 2013;36,S2:e45-e46.

Liu S, Jones L, Gu F. Long lasting front-of-the-eye drug delivery system: treatment of experimental dry eye. NSERC 20/20 Meeting, 2013.

Phan C, Subbaraman L, Jones L. Delivery of natamycin using cyclodextrin functionalized contact lenses. NSERC 20/20 Meeting, 2013.

Hui A, Willcox M, Jones L. In vitro evaluation of the antimicrobial properties of a novel silicone hydrogel material designed for the sustained release of the antibiotic ciprofloxacin. NSERC 20/20 Meeting, 2013.

Jones L. Contact lens materials, design, and care. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Verma M, Lehtovaara B, Jones L, Gu F. Beta-glucans for developing multifunctional drug delivery platforms. International Conference on Bioencapsulation, Berlin, Germany, 2013.

Liu S, Verma M, Jones L, Gu F. Long-lasting eye drop delivery platform for targeted ocular delivery applications. International Conference on Bioencapsulation, Berlin, Germany, 2013.

Hui A, Willcox M, Jones L. In vitro evaluation of the antimicrobial properties of a novel silicone hydrogel material designed for the sustained release of the antibiotic ciprofloxacin. ISCLR conference, Kyoto, Japan, 2013.

Phan C, Subbaraman L, Liu S, Gu F, Jones L. Drug delivery of natamycin from contact lens materials using Dex-b-PLA nanoparticles. ISCLR conference, Kyoto, Japan, 2013.

Korogiannaki M, Jones L, Sheardown H. Simultaneous release of a wetting agent and a therapeutic agent from model silicone hydrogel materials used for extended ocular drug delivery. Canadian Biomaterials Society Meeting, Ottawa, Canada, 2013.

Liu S, Jones L, Gu F. Mucoadhesive nanoparticles for topical ocular drug delivery. Canadian Biomaterials Society Meeting, Ottawa, Canada, 2013.

Jones L. A report card for silicone hydrogel contact lens materials: Pass or fail? . Canadian Biomaterials Society Meeting, Ottawa, Canada, 2013.

Jones L, Brennan N, Gonzalez-Meijome, Lally J, Maldonado-Codina C, Schmidt T, Subbaraman L, Young G. Contact lens materials, design and solutions: Relationship to contact lens discomfort. Tear Film & Ocular Surface Society meeting, Seattle, US, 2013.

Lorentz H, Sheardown H, Jones L. Lipid adherence to model contact lens materials. 20/20 NSERC ophthalmic materials conference, Niagara Falls, Canada, 2013.

Jones L, Hui A. Antibiotic drug delivery via contact lenses. 20/20 NSERC ophthalmic materials conference, Niagara Falls, Canada, 2013.

Phan C, Lui S, Gu F, Jones L. In vitro uptake and release of Natamycin dex-b-PLA nanoparticles from silicone hydrogel contact lens materials. 20/20 NSERC ophthalmic materials conference, Niagara Falls, Canada, 2013.

Schulze M, Simpson T, Situ P, Menzies K, Walther H, Jones L. Effects of magnification on tear meniscus parameters using optical coherence tomography (OCT) images. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement using infrared meibography systems. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Woods J, Woods C, Foon D, Jones L. Acceptance of a silicone hydrogel multifocal lens in emmetropic presbyopes. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Cheung S, Lorentz H, Drolle E, Leonenko Z, Jones L. Contact lens solution efficacy at removing in vitro tear film constituents from silicone hydrogel contact lenses: An atomic force microscopy study. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Phan C, Subbaraman L, Liu S, Gu F, Jones L. In vitro uptake and release of natamycin Dex-b-PLA nanoparticles from silicone hydrogel contact lens materials. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Walther H, Subbaraman L, Jones L. Method optimization to quantify oxidative stress in tear film lipids. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

McCanna D, Chang J, Subbaraman L, Jones L. Efficacy of contact lens solutions against Achromobacter xylosoxidans biofilms using confocal microscopy. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

McCanna D, Jones L. Membrane permeability of staphylococcus aureus aggregates exposed to contact lens care solutions. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Subbaraman L, Thangavelu M, McCanna D, Jones L. Tear film cytokine analyses using a novel electrochemiluminescent array technique. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Subbaraman L, Thangavelu M, McCanna D, Jones L. Quantification of lipocalin-1 in tears and contact lens deposits using a sandwich elisa technique. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Hall B, Phan C, Subbaraman L, Jones L, Forrest J. Extraction versus in situ techniques for measuring surface adsorbed lysozyme. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Mohammadi S, Jones L, Gorbet M. In vitro cell models for drug release studies from contact lenses. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Hui A, Jones L. Release of ciprofloxacin and dexamethasone from commercial contact lens materials. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Dare E, Subbaraman L, Jones L. Impact of environmental changes on in vitro corneal epithelial wound healing. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Srinivasan S, Keech A, Keir N, Jones L. Self vs. examiner-guided administration of ocular surface disease index (OSDI). Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Srinivasan S, Menzies K, Jones L. Meibography and lipid layer evaluation in Sjogren’s syndrome. Canadian Optometry Schools Research Conference, Waterloo, Canada, 2013.

Srinivasan S, Menzies K, Jones L. Infra-red imaging of meibomian glands & evaluation of the lipid layer in Sjogren’s syndrome patients. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement and repeatability of imaging the meibomian glands with the Oculus Keratograph 4 and Keratograph 5M. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Subbaraman L, Thangavelu M, McCanna D, Jones L. Quantifying tear film inflammatory markers using a novel, multiplex electrochemiluminescent technique. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

McCanna D, Jones L. Membrane permeability of staphylococcus aureus aggregates exposed to contact lens care solutions. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

McCanna D, Chang J, Subbaraman L, Jones L. Efficacy of contact lens solutions against Achromobacter xylosoxidans biofilms using confocal microscopy. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Dare E, Subbaraman L, Jones L. Impact of environmental changes on in vitro corneal epithelial wound healing. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Subbaraman L, Mistry R, Thangavelu M, Jones L. Quantification of lipocalin-1 in tears and contact lens deposits using a sandwich elisa technique. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Jones L, Varikooty J, Keir N, Soong F, Patel P. The evaluation of lid wiper epitheliopathy in contact lens wearers in a controlled low humidity enivironmental exposure chamber. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Patel P, Soong F, Salapatek AM, Varikooty J, Keir N, Jones L. Ocular signs and symptoms in contact lens wearers in a controlled low humidity environmental exposure chamber (LH-EEC) a natural provocation research model. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Salapatek AM, Soong F, Varikooty J, Keir N, Jones L, Patel P. In-vivo wettability of contact lenses worn in a low humidity environmental exposure chamber (LH-EEC) show comparable changes to traditional field trials. Tear Film & Ocular Surface International Conference, Sicily, Italy, 2013.

Otchere H, Sorbara L, Jones L. Repeatability and accuracy of the Oculus Pentacam HR corneal topographer in measuring radius of curvature and shape factor. Global Specialty Lens Symposium, Las Vegas, USA, 2013.

Hui A, Willcox M, Jones L. In vitro evaluation of antimicrobial activity of novel ciprofloxacin releasing silicone hydrogels. Optom Vis Sci 2013;90: E-Abstract130748.

Otchere H, Sorbara L, Jones L . Fitting semi-scleral contact lenses using corneal sagittal depth measurements and evaluation of visual acuity and comfort ratings. Optom Vis Sci 2013;90: E-Abstract 130968..

Srinivasan S, Keech A, Keir N, Jones L. Self vs. examiner-guided administration of ocular surface disease index (OSDI). Optom Vis Sci 2013;90: E-Abstract 130001.

Subbaraman L, Martell E, Heynen M, Ng A, Jones L. Kinetic activity of lysozyme when exposed to two differing contact lens care systems. Optom Vis Sci 2013;90: E-Abstract 130015.

Cheung S, Lorentz H, Drolle E, Leonenko Z, Jones L. Contact lens solution efficacy at removing in vitro tear film constituents from silicone hydrogel contact lenses: An atomic force microscopy study. Optom Vis Sci 2013;90: E-Abstract 135010.

Dumbleton K, Richter D, Jones L, Fonn D. Eye examination frequency and contact lens purchase patterns. Optom Vis Sci 2013;90: E-Abstract 135126.

Dumbleton K, Richter D, Woods C, Morgan P, Aakre BM, Jones L. Wearing and replacement patterns of patients using daily disposable contact lenses. Optom Vis Sci 2013;90: E-Abstract 135767.

Hui A, Jones L. Uptake and release of ciprofloxacin and dexamethasone from commercial contact lens materials. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 1086.

Gu F, Liu S, Jones L. Long-lasting eye drop delivery platform for targeted ocular delivery applications. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 1074.

McCanna D, Chang J, Subbaraman L, Jones L. Efficacy of contact lens solutions against Achromobacter xylosoxidans biofilms using confocal microscopy. Invest Ophthalmol Vis Sci 2013;54: EAbstract 523.

Walther H, Subbaraman L, Jones L. Efficacy of multi-purpose solutions in removing cholesterol desposits from silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 517.

Lorentz H, Guidi G, Jones L, Sheardown H. Lipid adherence to model contact lens materials. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 512.

Phan C, Subbaraman L, Jones L, Liu S, Gu F. In vitro uptake and release of natamycin dex-b-pla nanoparticles from silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 501.

Soong F, Varikooty J, Keir N, Jones L, Patel P. In-vivo wettability of contact lenses worn in a low humidity environmental exposure chamber (LH-EEC) show comparible changes to traditional field trials. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 499.

Gorbet M, Luensmann D, Jones L. The response of tear film neutrophils to occasional overnight lens wear. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 2069.

Jayakumar V, Hutchings N, Lakshminarayanan V, Jones L. Analysis of interocular surface aberrations using surface aberrometry. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 2608.

Ngo W, Srinivasan S, Schulze M, Jones L. Inter- and intra-observer agreement and repeatability of imaging the meibomian glands with the oculus Keratograph 4 and Keratograph 5M. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 3569. [ PDF ]

Subbaraman L, Thangavelu M, McCanna D, Jones L. Tear film cytokine analyses using a novel electrochemiluminescent array technique. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 4325.

Varikooty J , Lay B, Keir N, Burdin H, Jones L, Simpson T, Lemp J. The relationship between clinical grading and objective image analysis of lid wiper epitheliopathy. Invest Ophthalmol Vis Sci 2013;54: E-Abstract 5460.

2012

Gorbet M, Luensmann D, Luck S, Jones L. Response Of Tear Film Neutrophils To Different Stimuli. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 5271.

Srinivasan S, Menzies K, Sorbara L, Jones L. Infra-red Imaging Of Meibomian Gland Structure Using A Novel Keratograph. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 591.

Dumbleton K, Woods CA, Woods J, Moezzi A, Fonn D, Jones L. An Investigation Into The Role Of Masked Lens Replacement On Subjective Comfort And Vision With Aging Soft Contact Lenses . Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 4722.

Keir N, Richter D, Varikooty J, Jones L, Woods C, Fonn D. End Of Day Comfort Interpreted Using A Novel Cumulative Comfort Score. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 4728.

McCanna D, Jones L. Membrane Permeability Of Staphylococcus Aureus Aggregates Exposed To Contact Lens Care Solutions. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 6089.

Walther H, Subbaraman L, Jones L. In Vitro Dehydration of Daily Disposable and Silicone Hydrogel Contact Lens Materials . Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 6121.

Hall B, Jones L, Forrest J. Measuring The Kinetics and Activity of Adsorbed Proteins: In Vitro Lysozyme Deposited Onto Contact Lenses Over Short Time Periods. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 6125.

Situ P, McCanna D, Gorbet M, Jones L. Confocal Imaging Of Hyper-reflective Corneal Epithelial Cells During And After Contact Lens Wear . Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 4698.

Woods C, Keir N, Woods M, Jones L. The Development Of A New Grading Scale For In Vivo Front Surface Contact Lens Deposits. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 4700.

Soluri A, Hui A, Jones L. Ocular Delivery Of Ketotifen Fumarate By Silicone Hydrogel And Conventional Hydrogel Contact Lens Materials. Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 6101.

Lorentz H, Heynen M, Khan W, Trieu D, Jones L. The Impact of Intermittent Air Exposure on the Deposition of Lipids on Silicone Hydrogel and Conventional Hydrogel Contact Lens Materials . Invest Ophthalmol Vis Sci 2012;53:ARVO E-Abstract 3412.

Caffery B, Joyce E, Heynen M, Ritter R, Jones L, Senchyna M. TNF-Alpha MRNA expression in aqueous deficient dry eye. Optom Vis Sci 2012;89:E-abstract 120007.

Menzies K, Subbaraman L, Jones L. In vitro wettability comparison of hydrogel and silicone hydrogel daily disposable and frequent replacement contact lenses. Optom Vis Sci 2012;89:E-abstract 125032.

Ng A, Heynen M, Subbaraman L, Jones L. Optimization of a novel fluorescent based lysozyme activity assay for contact lens studies. Optom Vis Sci 2012;89:E-abstract 120052.

Dumbleton K, Richter D, Jones L. Compliance with lens replacement and the interval between eye examinations. Optom Vis Sci 2012;89:E-abstract 120059.

Hutchings N, Jayakumar V, Srinivasan S, Trusit D, Keir N, Jones L. Comparison of anterior surface aberrations between subjects with clinically stable and unstable tear films. Optom Vis Sci 2012;89:E-abstract 125122.

Varikooty J, Keir N, Jones L. Optimization of assessment and grading for lid wiper epitheliopathy. Optom Vis Sci 2012;89:E-abstract 120241.

Srinivasan S, Luensmann D, Otchere H, Yu M, Yang J, Jones L. The impact of cosmetics on the surface appearance and wettability of silicone hydrogel contact lenses. Optom Vis Sci 2012;89:E-abstract 120317.

Woods J, Keir N, Jones L. Solution-induced-corneal-staining (SICS): symptoms and staining patterns. Optom Vis Sci 2012;89:E-abstract 125625.

Dumbleton K, Woods C, Moezzi A, Fonn D, Jones L. The influence of masked lens replacement on subjective comfort and vision with aging soft contact lenses. Contact Lens & Anterior Eye 2012;35,S1:e38.

Luensmann D, Srinivasan S, Ochtere H, Yu M, Yang G, Jones L. The impact of cosmetics on the physical dimension and optical performance of silicone hydrogel contact lenses. Contact Lens & Anterior Eye 2012;35,S1:e6.

Woods J, Keir N, Jones L. The impact of saline rinsing on solution-induced corneal staining (SICS). Contact Lens & Anterior Eye 2012;35,S1:e36-e37.

Srinivasan S, Menzies K, Sorbara L, Jones L. Non-contact meibography using a novel keratograph. Contact Lens & Anterior Eye 2012;35,S1:e31-e32.

Schulze M, Varikooty J, Keir N, Jones L. The clinical performance of three contact lens solutions in symptomatic and asymptomatic contact lens wearers. Contact Lens & Anterior Eye 2012;35,S1:e8.

Keir N, Richter D, Varikooty J, Jones L, Woods C, Fonn D. End of day comfort interpreted using a novel cumulative comfort score for symptomatic contact lens wearers. Contact Lens & Anterior Eye 2012;35,S1:e37.

Keir N, Varikooty J, Richter D, Jones L, Woods C, Fonn D. Evaluation of lens surface appearance and ocular physiology with three silicone hydrogel daily disposables. Contact Lens & Anterior Eye 2012;35,S1:e6.

Varikooty J, Keir N, Richter D, Jones L, Woods C, Fonn D. Subjective comfort with three silicone hydrogel daily disposables in symptomatic contact lens wearers. Contact Lens & Anterior Eye 2012;35,S1:e7-e8.

Menzies K, Jones L. Sessile drop contact angle analysis of hydrogel and silicone hydrogel daily disposable and frequent replacement contact lenses. Contact Lens & Anterior Eye 2012;35,S1:e12-e13.

Woods C, Keir N, Woods M, Jones L. A new video-based tool for grading clinical observations of soft lens surface deposits. Contact Lens & Anterior Eye 2012;35,S1:e37-e38.

Srinivasan S, Menzies K, Sorbara L, Jones LW. Appearance of meibomian gland structures imaged using a Keratograph. Global Specialty Lens Symposium, 2012.

Jones L, Keir N. Comfort from a different view. Materials Science and Chemistry of Contact Lenses, New Orleans, 2012.

Subbaraman L, Sheardown H, Jones L. 2. Incorporating novel agents to improve the wettability of contact lens materials. Materials Science and Chemistry of Contact Lenses, New Orleans, 2012.

Gorbet M, Mohammadi S, Jones L. Investigation of drug-release materials using in vitro cell models. 2020 NSERC ophthalmic materials conference, Burlington, Canada, 2012.

Phan C, Jacob J, Subbaraman L, Jones L. Visualizing the uptake and release of natamycin from commercial contact lenses using confocal microscopy. 2020 NSERC ophthalmic materials conference, Burlington, Canada, 2012.

2011

Guthrie S, Woods J, Keir N, Dillehay S, Tyson M, Griffin R, Fonn D, Jones L, Irving E. Controlling lens induced myopia in chickens with peripheral lens design. Optom Vis Sci 2011;88:E-Abstract 110421.

Dumbleton K, Woods C, Fonn D, Jones L. An internet based survey to investigate lapsed contact lens wearers in Canada. International Society for Contact Lens Research (Napa Valley, California), 2011.

Jones L, Lorrentz H, Walther H, Heynen M, Kay L. Impact of lipid concentration, exposure time and tear film components on in vitro model lipid deposition to silicone hydrogel and hydrogel contact lens materials. International Society for Contact Lens Research (Napa Valley, California), 2011.

Jones L. Contact lens solutions: What do we really know?. International Society for Contact Lens Research (Napa Valley, California), 2011.

Gorbet M, Tanti N, Jones L. Impact of contact lens solution/material combinations on corneal epithelial cells in vitro. International Society for Contact Lens Research (Napa Valley, California), 2011.

Sheardown H, Wells L, Josephson J, Myers R, Jones L. Self destructive cases for improved patient compliance. International Society for Contact Lens Research (Napa Valley, California), 2011.

Woods J, Guthrie S, Keir N, Choh V, Fonn D, Jones L, Irving E. Myopia development – what can the chicken tell us?. Contact Lens & Anterior Eye 2011;34,Supplement 1:s13.

Muntz A, Lorentz H, Walther H, Heynen M, Joyce E, Sickenberger W, Jones L. Utility of a pulsating contact lens case to aid cholesterol removal from contact lens materials soaked in a no-rub MPS regimen. Contact Lens & Anterior Eye 2011;34,S1:S9.

Jones L. Compliance: Just how bad is it?. Contact Lens & Anterior Eye 2011;34,Supplement 1:S4.

Jones L. The contact lens market today: An overview of trends. 15th symposium on the Materials Science and Chemistry of Contact Lenses (New Orleans, USA), 2011.

Lorrentz H, Khan W, Trieu D, Heynen M, Jones L. The effect of intermittent air exposure on the deposition of lipids on silicone hydrogel and conventional hydrogel contact lens materials. NSERC 2020 Network Meeting (Orllia, Ontario), 2011.

Kao E, McCanna D, Jones L. In vitro model for determining the viability and strength of adhesion of human lens epithelial cells to silicone. NSERC 2020 Network Meeting (Orllia, Ontario), 2011.

Lorrentz H, Khan W, Trieu D, Heynen M, Jones L. The effect of intermittent air exposure on the deposition of lipids on silicone hydrogel and conventional hydrogel contact lens materials. International Society for Contact Lens Research (Napa Valley, California), 2011.

McCanna D, Mikkelsen S, Rahimi M, So F, Zhou Y, Sivak J, Jones L. Determining toxicity thresholds in ocular in vitro test batteries using benzalkonium chloride. International Society for Contact Lens Research (Napa Valley, California), 2011.

Fisher G, Leung T, Luensmann D, Heynen M, Jones L. 3D TOF-SIMS characterisation of drug-loaded silicone hydrogel contact lenses in the frozen hydrated state. 18th SIMS Conference (Trentino, Italy), 2011.

Walther H, Lorrentz H, Kay L, Heynen M, Jones L. The effect of in vitro lipid concentration on lipid deposition on silicone hydrogel and conventional hydrogel contact lens materials. Contact Lens & Anterior Eye 2011;34,S1:S21.

Hui A, Sheardown H, Jones LW. Molecular Imprinted Silicone Hydrogels for Ciprofloxacin Drug Delivery. International Society for Contact Lens Research (ISCLR) Meeting (Napa Valley, California), 2011.

Hui A, Boone A, Jones L. Uptake and Release of Ciprofloxacin and Dexamethasone from Commercially Available Conventional and Silicone Hydrogel Materials. 15th Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans, USA), 2011.

Anderson T, Moezzi A, Varikooty J, Jones L, Woods C, Fonn D. A novel method for measuring contact lens movement and centration using a high speed camera and computer vision. Optom Vis Sci 2011;88:E-abstract 115439.

Dumbleton K, Woods C, Jones L, Fonn D. Comparing contact lens compliance and complications in a university clinic with private optometry offices. Optom Vis Sci 2011;88:E-abstract 110257.

Dumbleton K, Woods C, Jones L, Fonn D. A survey to investigate lapsed contact lens wearers in Canada. Optom Vis Sci 2011;88:E-abstract 110416.

Hui A, Sheardown H, Jones L. Molecular imprinted silicone hydrogel materials for ciprofloxacin drug delivery. Optom Vis Sci 2011;88: E-abstract 110429.

Jadi S, Heynen M, Luensmann D, Jones L. Incubation solution composition impacts in vitro protein uptake to silicone hydrogel contact lenses. Optom Vis Sci 2011;88:E-abstract 110546.

Moezzi A, Situ P, Luensmann D, Fonn D, Woods C, McNally J, Jones L. Does comfort with aging silicone hydrogel lenses relate to changes in lens fit and conjunctival staining?. Optom Vis Sci 2011;88:E-abstract 115708.

Jones L. Uptake and release of preservatives into soft lenses: Clinical implications. Global Contact Lens Care Summit, Seatle, WA, 2011.

Ng A, Heynen M, Jones L. The impact of lactoferrin and lipids on kinetic lysozyme deposition on contact lenses. Optom Vis Sci 2011;88:E-abstract 110771.

Schulze M, Simpson T, Situ P, Menzies K, Walther H, Jones L. Effects of magnification on tear meniscus parameters using optical coherence tomography (OCT) images. Optom Vis Sci 2011;88:E-abstract 115482.

Situ P, Simpson T, Schultze M, Menzies K, Walther H, Jones L. Intra- and inter-operator variability of meridional corneal and epithelial thickness measurements obtained using optical coherence tomography (OCT). Optom Vis Sci 2011;87: E-abstract 115021.

Srinivasan S, Menzies K, Sorbara L, Jones L. Imaging meibomian gland structures using the oculus keratograph. Optom Vis Sci 2011;87:E-abstract 110775.

Woods M, Dumbleton K, Woods C, Jones L, Fonn D. Do contact lens wearers remember what products they are using?. Optom Vis Sci 2011;87:E-abstract 115811.

Woods J, Guthrie S, Keir N, Dillehay S, Tyson M, Griffin R, Jones L, Irving E. The effect of a unique lens designed for myopia progression control (MPC) on the level of induced myopia in chicks. Invest Ophthalmol Vis Sci 2011;51:E-Abstract 6651.

Lorentz H, Walther H, Heynen M, Kay L, Jones L. Radiochemical kinetic uptake of three lipids on silicone hydrogel and conventional hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2011;52:E-Abstract 6479.

Situ P, Simpson T, Jones L, Fonn D, Woods C. The relationship between solution induced corneal staining and ocular surface sensitivity. Invest Ophthalmol Vis Sci 2011;51:E-Abstract 6514.

Hui A, Weeks A, Sheardown H, Jones L. Novel silicone hydrogel contact lens materials for ciprofloxacin drug delivery. Invest Ophthalmol Vis Sci 2011;52:E-Abstract 6531.

2010

Jones L. Contact lens solutions: Where next? Keynote address. Tear Film and Ocular Surface Society (Florence, Italy), 2010.

Jones L. The role of disinfecting solutions on contact lens performance and success. international Society for Eye Research (Montreal, Canada), 2010.

Jones R, Jones L. In vitro bulk dehydration rates of hydrogel and silicone hydrogel daily disposable and frequent replacement contact lens materials. 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Srinivasan S, Martell E, Heynen M, Jones L. Clinical signs, tear lipocalin and lysozyme concentrations in postmenopausal women symptomatic of dry eye . 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Heynen M, Lorentz H, Dumbleton K, Varikooty J, Woods C, Jones L. Lipid deposition on senofilcon A silicone hydrogel contact lenses disinfected with 1-step hydrogen peroxide and polyquad/aldox-preserved care regimens. 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Srinivasan S, Martell E, Heynen M, Luensmann D, Cira D, Gorbet M, Jones L. Ocular surface sampling techniques. 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Hui A, Weeks AK, Sheardown H, Jones L. Novel contact lens materials for ciprofloxacin drug delivery. 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Lorentz H, Heynen M, Jones L. Impact of tear film components on in vitro lipid uptake to silicone hydrogel and hydrogel contact lens materials. 7th Canadian University Conference in Optometry (Montreal, Canada), 2010.

Weeks AK, Jones L, Sheardown H. Imprinted HA as a releasable wetting agent in model contact lenses. 20:20 National Science and Engineering Council Network Meeting (Horseshoe Valley, Ontario, Canada), 2010.

Hui A, Weeks AK, Sheardown H, Jones L. Novel contact lens materials for ciprofloxacin drug delivery. 20:20 National Science and Engineering Council Network Meeting (Horseshoe Valley, Ontario, Canada), 2010.

Srinivasan S, Martell E, Heynen M, Luensmann D, Cira D, Gorbet M, Jones L. Ocular surface sampling techniques. 20:20 National Science and Engineering Council Network meeting (Horseshoe Valley, Ontario, Canada), 2010.

Lorrentz H, Heynen M, Jones L. Impact of tear film components on in vitro lipid uptake to silicone hydrogel and hydrogel contact lens materials. 20:20 National Science and Engineering Council Network Meeting (Horseshoe Valley, Ontario, Canada), 2010.

Dumbleton K, Richter D, Woods C, Jones L, Fonn D. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement in Canada. Ontario Association of Optometrists, 2010.

Jones L, Jones R. In vitro bulk dehydration rates of hydrogel and silicone hydrogel daily disposable and frequent replacement contact lens materials. Optom Vis Sci 2010;87:E-abstract 105217.

Dumbleton K, Richter D, Woods C, Jones L, Fonn D. Relationship between compliance with lens replacement and contact lens related problems in silicone hydrogel wearers. Optom Vis Sci 2010;87:E-abstract 100183.

Woods C, Dumbleton K, Richter D, Jones L, Fonn D. Compliance with lens care and contact lens case care and replacement. Optom Vis Sci 2010;87:E-abstract 100194.

Sorbara L, Richter D, Peterson R, Schneider S, Woods C, Jones L, Fonn D. Comparison between live and digital slit lamp images of corneal staining. Optom Vis Sci 2010;87:E-abstract 100083.

Jones L, Rodriguez Celis E, Tourigny M, Blain A. Elemental analysis of hydrogel contact lenses using laser-induced breakdown spectroscopy (LIBS). Contact Lens & Anterior Eye 2010;33,6:295.

Jones L, Joyce E, Heynen M. Utility of a contact lens case pulsator to aid lysozyme removal from etafilcon A hydrogel lenses soaked in a no rub MPS regimen. Contact Lens & Anterior Eye 2010;33,6:290.

Jones L, Nguyen D, Weeks A, Heynen M, Joyce E, Sheardown H. Uptake and release of ciprofoloxacin by soft contact lens materials loaded with hyaluronic acid. Contact Lens & Anterior Eye 2010;33,6:286.

Peterson R, Fonn D, Woods C, Jones L. How to stop SICS!. Contact Lens & Anterior Eye 2010;33,6:272.

Jones L. Against the motion: With modern silicone hydrogel lenses continuous wear is not a crazy idea. Contact Lens & Anterior Eye 2010;33,6:271.

Lorentz H, Heynen M, Jones L. The impact of tear film components on in vitro lipid uptake to silicone hydrogel and hydrogel contact lens materials. Contact Lens & Anterior Eye 2010;33,6:268.

Jones L. What your patients don’t tell you!. Contact Lens & Anterior Eye 2010;33,6:265.

Dumbleton K, Woods C, Jones L, Richter D, Fonn D. The effect of compliance with replacement frequency on comfort and vision with silicone hydrogel lenses. Contact Lens & Anterior Eye 2010;33,6:263.

Jones L, Menzies K. In vitro analysis of the physical properties of blister pack solutions of silicone hydrogel contact lenses. Contact Lens & Anterior Eye 2010;33,6:262.

Jones L. New specialist lens solutions and care techniques. Contact Lens & Anterior Eye 2010;33,6:260.

Menzies K, Jones L. In vitro analysis of the physical properties of blister pack solutions of silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2010;51:E-Abstract 1526.

Rodriguez Celis E, Tourigny M, Blain A, Jones L. Elemental analysis of hydrogel contact lenses using laser-induced breakdown spectroscopy (LIBS). Invest Ophthalmol Vis Sci 2010;51:E-Abstract 3411.

Jones L, Nguyen D, Weeks AK, Heynen M, Joyce E, Sheardown H. Uptake and release of ciprofloxacin by soft contact lens materials loaded with hyaluronic acid. Invest Ophthalmol Vis Sci 2010;51:ARVO E-Abstract 3412.

Gorbet M, Tanti N, Crockett B, Jones L. Impact of lens material on in vitro cytotoxicity potential of multipurpose solutions on human corneal epithelial cells. Invest Ophthalmol Vis Sci 2010;51:E-Abstract 3415.

Weeks AK, Jones L, Sheardown H. Imprinted HA as a releasable wetting agent in model contact lenses. Invest Ophthalmol Vis Sci 2010;51:E-Abstract 3420.

Keech A, Senchyna M, Sullivan BD, Lemp MA, Jones L, Brubaker MJ. Impact of time between collection on human tear film fluid osmolarity. Invest Ophthalmol Vis Sci 2010;51:E-Abstract 4174.

Forrest J, Kaur K, Ilic K, Hall B, Jones L. In situ measurements of protein structural changes during adsorption. American Physical Society 2010:Abstract #J10.012.

2009

Nguyen D, Weeks A, Heynen M, Joyce E, Sheardown H, Jones L. Uptake and release of ciprofloxacin by soft contact lens materials loaded with hyaluronic acid. 20:20 National Science and Engineering Council (NSERC) Network Meeting (Toronto, Canada), 2009.

Jones L. Contact lens materials update - the rise of siloxane-based materials. 20:20 National Science and Engineering Council (NSERC) Opthalmic Materials Network meeting (Waterloo, Canada), 2009.

Keir N, Srinivasan S, Jones L, Woods C, Fonn D. The performance of a silicone hydrogel daily disposable contact lens in a group of asymptomatic silicone hydrogel lens wearers. Asia Pacific Contact Lens Meeting (Hong Kong), 2009.

Dumbleton K, Woods C, Jones L, Guthrie S, Fonn D. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement. Contact Lens & Anterior Eye 2009;32,5:213.

Jones L, Brodland G, Horst C, McDonald M, Guthrie S. A novel method for measuring contact lens tensile properties. Contact Lens & Anterior Eye 2009;32,5:254.

Jones L, Heynen M, Joyce E, Lorentz H, Dumbleton K, Varikooty J, Woods C. Tear film deposition on silicone hydrogel contact lenses disinfected with hydrogen peroxide and rub or enhanced no-rub care regimens. Contact Lens & Anterior Eye 2009;32,5:249.

Menzies K, Jones L. In vitro analysis of wettability and physical properties of blister pack solutions of daily disposable lenses. Contact Lens & Anterior Eye 2009;32,5:248.

Subbaraman L, Jones L. In vitro wettability of surface modified and non-surface modified silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2009;32,5:240.

Dalton K, Schneider S, Jones L, Sorbara L. OCT and confocal imaging techniques used in the evaluation of two cases of hereditary granular dystrophy. Contact Lens & Anterior Eye 2009;32,5:235.

Subbaraman L, Jones L, Zhao Z, Zhu H, Willcox M. Bacterial adhesion to lysozyme-coated conventional and silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2009;32,5:229.

Luensmann D, Heynen M, Jones L. Penetration profile of lysozyme and albumin in silicone hydrogel and pHEMA-based contact lens materials assessed using confocal microscopy. Contact Lens & Anterior Eye 2009;32,5:224.

Dalton K, Hui A, Jones L, Simpson T. Diurnal variation in tear film osmolality, stability, ocular surface redness and ocular comfort. Contact Lens & Anterior Eye 2009;32,5:220.

Jones L. But we forgot solutions!. Contact Lens & Anterior Eye 2009;32,5:215.

Jones L. Microbial keratitis - I saw it coming!. Contact Lens & Anterior Eye 2009;32,5:212.

Horst CR, McDonald M, Brodland G, Jones L. Extracting properties from variable thickness tensile specimens: A contact lens study. International Conference on Mechanics of Biomateials & Tissues (Clearwater Beach, Florida), 2009.

Peterson R, Woods C, Jones L, Fonn D. The impact of rub and rinse on solution-induced corneal staining. ISCLR Meeting (Crete), 2009.

Subbaraman L, Jones L, Borazjani R, Zhao Z, Zhu H, Willcox M. Bacterial adhesion to lactoferrin-coated conventional and silicone hydrogel contact lens materials. International Society of Contact Lens Research (ISCLR) Meeting (Crete), 2009.

Weeks A, Luensmann D, Jones L, Sheardown H. Crosslinked HA decrease lysozyme sorption and denaturation in model contact lens materials. 20:20 National Science and Engineering Council (NSERC) Network meeting (Toronto, Canada), 2009.

Dumbleton K, Woods C, Jones L, Fonn D. Does compliance with replacement frequency of silicone hydrogel lenses play a role in subjective comfort and vision rating?. ISCLR meeting (Crete, Greece), 2009.

Dumbleton K, Richter D, Guthrie S, Woods C, Jones L, Fonn D. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement. CAO (Charlottetown, PEI), 2009.

Luensmann D, Heynen M, Jones L. Determination of albumin sorption to intraocular lenses by radiolabeling and confocal scanning laser microscopy. Ivey Research Institute Day (London, Canada), 2009.

Subbaraman L, Jones L, Zhao Z, Zhu H, Willcox MDP. Bacterial adhesion to protein-coated conventional and silicone hydrogel contact lens materials. Ivey Institute Research Day (London, Ontario), 2009.

Weeks A, Jones L, Sheardown H. Incorporating HA as an internal wetting agent. Canadian Biomaterials Society annual meeting (Quebec City, Canada), 2009.

Subbaraman LN, Jones L, Borazjani R, Zhao Z, Zhu H, Willcox MDP. Bacterial adhesion to proteincoated conventional and silicone hydrogel contact lens materials. 15th Scientific Meeting of the International Society for Contact Lens Research (Crete, Greece), 2009.

Heynen M, Lorentz H, Dumbleton K, Varikooty J, Woods C, Jones L. Lipid deposition on senofilcon A silicone hydrogel contact lenses disinfected with 1-step hydrogen peroxide and polyquad/aldox-preserved care regimens. Invest Ophthalmol Vis Sci 2009;49:E-abstract 5660.

Situ P, Simpson T, Jones L, Fonn D. Changes in corneal and conjunctival sensitivity with silicone hydrogel lens wear. Invest Ophthalmol Vis Sci 2009;50:E-abstract 6347.

Tanti N, Jones L, Gorbet M. Effect of MPS released from silicone hydrogel lenses on corneal epithelial cell adhesion phenotype and apoptotic pathways in vitro. Invest Ophthalmol Vis Sci 2009;50:E-abstract 4614.

Weeks A, Jones L, Sheardown H. Incorporating HA as an internal wetting agent. Invest Ophthalmol Vis Sci 2009;50:E-abstract 5651.

Brodland G, Jones L, Horst C, McDonald M, Guthrie S. A novel method for measuring contact lens tensile properties. Optom Vis Sci 2009;86:E-abstract 095818.

Dumbleton K, Woods CA, Jones L, Fonn D. The role of compliance with replacement frequency of silicone hydrogel lenses on subjective comfort and vision. Optom Vis Sci 2009;86:E-abstract 090626.

Dumbleton K, Richter D, Woods CA, Jones L, Fonn D. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement in USA and Canada. Optom Vis Sci 2009;86:E-abstract 90615.

Jones L, Heynen M, Joyce E, Lorentz H, Dumbleton K, Varikooty J, Woods C. Tear film deposition on silicone hydrogel contact lenses disinfected with hydrogen peroxide and rub or enhanced no-rub care regimens. Optom Vis Sci 2009;86:E-abstract 095929.

Jones L, Joyce E, Heynen M. Utility of a contact lens case pulsator to aid lysozyme removal from etafilcon A hydrogel lenses soaked in a no rub MPS regimen. Optom Vis Sci 2009;86:E-abstract 090650.

Keech A, Simpson T, Flanagan J, Jones L. Repeatability of pachymetry measures by the RTVue-100 spectral domain optical coherence tomographer. Optom Vis Sci 2009;86:E-abstract 095916.

Luensmann D, Heynen M, Liu L, Sheardown H, Jones L. The impact of rub & no-rub care products on protein removal and localization. Optom Vis Sci 2009;86:E-abstract 090517.

Spurr-Michaud SJ, Senchyna M, Srinivasan S, Ritter III R, Heikkila E, Heynen M, Jones L, Gipson I. Assay of membrane-associated mucins in conjunctiva and tears of postmenopausal women with and without dry eye. Invest Ophthalmol Vis Sci 2009;50: E-Abstract 539.

Stahl U, Jones L, Willcox M, Stapleton F. Tear osmolality measurements - effect of instrumentation and of freezing. Invest Ophthalmol Vis Sci 2009;50: E-abstract 2611.

Ngo W, Heynen M, Joyce E, Jones L. Impact of protein, lipid and lens polymer on neutralization times of hydrogen peroxide care regimens. Optom Vis Sci 2009;86:E-abstract 095631.

Peterson R, Schneider S, Woods CA, Jones L, Fonn D. Optimising fluorescein observations of solution induced corneal staining. Optom Vis Sci 2009;86:E-abstract 95820.

Subbaraman LN, Jones L. In vitro wettability of surface modified and non-surface modified silicone hydrogel contact lens materials. Optom Vis Sci 2009;86:E-abstract 095754.

Subbaraman L, Jones L, Borazjani R, Zhao Z, Zhu H, Willcox M. Bacterial adhesion to lactoferrin-coated conventional and silicone hydrogel contact lens materials. Optom Vis Sci 2009;86:E-abstract 090758.

2008

Jones L, Subbaraman L. In vitro wettability of a non surface modified silicone hydrogel contact lens material. Contact Lens & Anterior Eye 2008;31,5:262.

Menzies K, Jones L. In vitro wettability of a novel surface-modified silicone hydrogel material (Asmofilcon A). Contact Lens & Anterior Eye 2008;31,5:261.

Tanti N, Gorbet M, Jones L. In vitro analysis of the potential cytotoxicity of contact lenses soaked in multi-purpose solutions. Contact Lens & Anterior Eye 2008;31,5:250-251.

Jones D, Jones L. The use of O2Optix Custom in a case of pediatric aphakia. Contact Lens & Anterior Eye 2008;31,5:246.

Subbaraman L, Chow L, Sheardown H, Jones L. Lactoferrin uptake kinetics on silicone hydrogel and conventional hydrogel contact lens materials. Optom Vis Sci 2008;85: E-Abstract 085047.

Srinivasan S, Joyce E, Boone A, Simpson T, Jones L, Senchyna M. Clinical characteristics and tear lysozyme concentration in dry eyed postmenopausal women. Optom Vis Sci 2008;85: E-Abstract 070069.

Keir N, Boone A, Dumbleton K, Jones L, Woods C, Fonn D. In vivo and ex vivo wettability and the association with contact lens comfort. Contact Lens & Anterior Eye 2008;31,6:292.

Gorbet M, Jones L, Sheardown H. The adverse effect of borate buffered versus phosphate buffered packaging solutions on corneal cellular viability and integrin expression. Contact Lens & Anterior Eye 2008;31,6:290-291.

Jones L. Allergy vs toxicity – what’s the difference clinically?. Contact Lens & Anterior Eye 2008;31,6:297.

Hui A, Boone A, Jones L. Uptake and release of Ciprofloxacin-HCl from conventional and silicone hydrogel contact lens materials. Rising Stars of Research Conference (Alberta, Canada), 2008.

Bitton E, Jones L, Simpson T. Temporal sequencing of the tear meniscus height. Optom Vis Sci 2008;85: E-abstract 80015.

Dalton K, Jones L, Guthrie S. pH, Osmolality and viscosity of artificial tears. Optom Vis Sci 2008;85: E-abstract 85310.

Dalton K, Senchyna M, Srinivasan S, Jones L. Tear film osmolality in a symtomatic dry eyes population. Optom Vis Sci 2008;85: E-abstract 85314.

Dalton K, Schneider S, Jones L, Sorbara L. Use of digital imaging in sisters with hereditary granular dystrophy. Optom Vis Sci 2008;85:E-abstract 85292.

Luensmann D, Heynen M, Jones L. Albumin penetration into intraocular lenses imaged by confocal microscopy. Optom Vis Sci 2008;85; E-abstract 80029.

Srinivasan S, Simpson T, Senchyna M, Jones L. Assessment of ocular surface dryness in postmenopausal females using dry eye questionnaires. Optom Vis Sci 2008;85: E-abstract 80023.

Subbaraman L, Jones L, Zhao Z, Zhu H, Willcox M. Bacterial adhesion to lysozyme-coated conventional and silicone hydrogel contact lens materials. Optom Vis Sci 2008;85:E-abstract 80108.

Srinivasan S, Simpson T, Senchyn M, Jones L. Use of dry eye questionnaires to assess ocular surface dryness in postmenopausal females with and without dry eye. Invest Ophthalmol Vis Sci 2008;49: E-abstract 5850.

Subbaraman L, Chow L, Sheardown H, Jones L. Kinetics of in vitro lactoferrin deposition on FDA group II, FDA group IV and silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2008;49: E-abstract 2022.

Weeks AK, Sheardown H, Jones L. The effects of crosslinked hyaluronic acid on pHEMA and pHEMA/TRIS hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2008;49: E-abstract 4866.

Dalton K, Jones L, Guthrie S. Physical properties of artificial tears. Contact Lens & Anterior Eye 2008;31,5:272.

Jones L, Subbaraman L, Glasier MA, Dumbleton K. Quantification of protein deposition on five commercially available silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2008;31,5:263.

Jones L, Glasier M, Boone A, Keir N, Dumbleton K. Protein deposition on continuous wear surface modified (balafilcon a) and non-surface modified (comfilcon a) silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2008;31,5:263.

Jones L, Boone A, Heynen M, Joyce E, Varikooty J. Ex vivo protein deposition on two-weekly daily wear silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2008;31,5:262-263.

Jones L, Subbaraman L, Woods J. Protein deposition on a novel lathe-cut silicone hydrogel contact lens material (sifilcon A). Contact Lens & Anterior Eye 2008;31,5:262.

2007

Subbaraman L, Jones L. Activity of lysozyme deposited on conventional and silicone hydrogel contact lenses as a function of time. Invest Ophthalmol Vis Sci 2007;47:E-Abstract 5393.

Dumbleton K, Woods C, Jones L, Fonn D. Comfort and adaptation to silicone hydrogel lenses for daily wear. BCLA, 2007.

Subbaraman L, Jones L. An in vitro comparison of the activity of lysozyme recovered from contact lens materials as a function of time. Optom Vis Sci 2007;84:E-abstract 075141.

Subbaraman L, Jones L. In vitro wettability of a non-surface-modified silicone hydrogel contact lens material. Optom Vis Sci 2007;84:E-abstract 075172.

Subbaraman L, Glasier MA, Dumbleton K, Jones L. Quantification of protein deposition on five commercially available silicone hydrogel contact lens materials. Optom Vis Sci 2007;84:E-abstract 070031.

Subbaraman L, Woods J, Jones L. Protein deposition on a novel lathe-cut silicone hydrogel contact lens material (sifilcon A). Optom Vis Sci 2007;84:E-abstract 070038.

Boone A, Heynen M, Joyce E, Varikooty J, Jones L. Ex vivo protein deposition on two-weekly daily wear silicone hydrogel contact lens materials. Optom Vis Sci 2007;84: E-abstract 075140.

Caffery B, Joyce E, Boone A, Jones L, Simpson T, Slomovic A, Senchyna M. Tear flow and lysozyme concentration in Sjogren’s Syndrome, KCS and normals. Optom Vis Sci 2007;84: E-abstract 075333.

Jones D, Jones L. The use of 02Optix Custom in a case of pediatric aphakia. Optom Vis Sci 2007;84: E-abstract 075149.

Jones L, Glasier MA, Boone A, Keir N, Dumbleton K. Protein deposition on continuous wear surface modified (balafilcon A) and non-surface-modified (comfilcon A) silicone hydrogel contact lens materials. Optom Vis Sci 2007;84: E-abstract 075139.

Keir N, Simpson T, Jones L, Fonn D. The relationship between manifest refraction and higher order aberrations for wavefront-guided LASIK. Optom Vis Sci 2007;84: E-abstract 075084.

Woods J, Schneider S, Woods CA, Jones LW, Fonn D. Short term satisfaction and physiological response in wearers of high power hydrogel lenses refit with a custom silicone hydrogel lens. Optom Vis Sci 2007;84: E-abstract 070034.

Srinivasan S, Joyce E, Jones L, Simpson T, Gamache D, Senchyna M. Clinical characteristics and tear lipocalin concentration in dry eyed postmenopausal women. Optom Vis Sci 2007;84: E-abstract 075330.

Gorbet M, Duan X, Jones L, Sheardown H. Activation of human corneal epithelial cells on collagen gels. Invest Ophthalmol Vis Sci 2007;48: E-abstract 1891.

Luensmann D, Heynen M, Jones L. The use of confocal microscopy to investigate albumin penetration into pHEMA-based and silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2007;48: E-abstract 5377.

Srinivasan S, Joyce E, Jones L, Senchyna M. Comparison of tear lipocalin ratios in asymptomatic and symptomatic dry eyed postmenopausal women. Invest Ophthalmol Vis Sci 2007;48: E-abstract 6024.

Jones L, Subbaraman LN, Varikooty J, Srinivasan S, Glasier M. Activity of lysozyme deposited on oneday etafilcon contact lenses is correlated with subjective comfort. 14th Scientific Meeting of the International Society for Contact Lens Research (Whistler, Canada), 2007.

Srinivasan S, Joyce E, Jones L, Simpson T, Senchyna M. Comparison of tear lipocalin ratios in dry eyed and non dry eyed postmenopausal women. 6th Canadian Optometry Conference on Vision Science (Waterloo, Ontario), 2007.

Dumbleton K, Jones L, Woods CA, Feng Y, Moezzi A and Fonn D. Clinical performance of a hydrogen peroxide care regimen with silicone hydrogel lenses. Contact Lens & Anterior Eye 2007;30,5:301.

Subbaraman L, Jones L. In vitro wettability of a non surface modified silicone hydrogel contact lens material. 6th Canadian Optometry Conference on Vision Science (Waterloo, Ontario), 2007.

Jones L, Subbaraman L. Kinetics of lysozyme activity recovered from conventional and silicone hydrogel lenses. Contact Lens & Anterior Eye 2007;30,5:284-285.

Jones L, Srinivasan S, Joyce E, Senchyna M. Increased tear osmolality and altered tear ferning patterns in postmenopausal women with mild and moderate symptoms of dry eye. Contact Lens & Anterior Eye 2007;30,5:293.

Spurr-Michaud S, Senchyna M, Srinivasan S, Ritter R, Argueso P, Joyce E, Heynen M, Jones L, Gamache D, Gipson I. Assay of MUC16 in conjunctiva and tears of postmenopausal women with and without dry eye. 5th International Conference on the Tear Film and Ocular Surface (Sicily, Italy), 2007.

Jones L, Subbaraman L, Srinivasan S, Varikooty J, Glasier M. Subjective comfort is correlated with the activity of lysozyme recovered from one-day etafilcon lenses. British Contact Lens Association Annual Meeting, Manchester, England, 2007.

Srinivasan S, Joyce E, Heynen M, Jones L, Simpson T, Gamache D, Senchyna M. Expression of soluble and membrane bound MUC16 in dry eyed postmenopausal women. 5th International Conference on the Tear Film and Ocular Surface (Sicily, Italy), 2007.

Caffery B, Joyce E, Heynen M, Ritter R, Jones L, Simpson T, Slomovic A, Gamache D, Senchyna M. Tear flow and MUC16 expression in Sjögren’s Syndrome, KCS and normals. 5th International Conference on the Tear Film and Ocular Surface (Sicily, Italy), 2007.

Varikooty J, Srinivasan S, Chan A, Subbaraman L, Woods C, Simpson T, Jones L, Fonn D. Clinical manifestations of upper lid staining in adapted silicone hydrogel lens wearers. British Contact Lens Association Annual meeting (Manchester, UK), 2007.

Bitton E, Keech A, Simpson T, Jones L. Inter- and intra-observer variability in TMH using the OCT. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Bitton E, Keech A, Jones L. Overnight variation in tear ferning. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Dalton K, Subbaraman L, Rogers R, Jones L. Physical properties of soft contact lens solutions. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Jones L. Ocular biomaterials and their interaction with the human tear film. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Lorentz H, Rogers R, Jones L. The impact of in vitro lipid deposition on contact angle wettability of various contact lens materials. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Luensmann D, Heynen M, Jones L. The use of confocal microscopy to investigate albumin penetration into pHEMA-based and silicone hydrogel contact lens materials. Biomedical Imaging and Computer Vision (BICV) Workshop (University of Waterloo, Canada), 2007.

Lorentz H, Campbell F, Subbaraman L, Jones L. The impact of drop solution on the out of pack wettability of conventional and silicone hydrogel contact lens materials. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Luensmann D, Heynen M, Jones L. The use of confocal microscopy to investigate albumin penetration into pHEMA-based and silicone hydrogel contact lenses. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Srinivasan S, Jones L, Joyce E, Simpson T, Senchyna M. Clinical signs and symptoms in post-menopausal females with dry eye. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Srinivasan S, Jones L, Joyce E, Simpson T, Senchyna M. Comparsion of tear lipocalin ratios in dry eyed and non-dry eyed post-menopausal woman. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Situ P, Simpson T, Jones L, Fonn D. Conjunctival and corneal sensitivity associated with dry eye symptomatology. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Subbaraman L, Jones L. An in vitro comparison of the activity of lysozyme recovered from contact lens materials as a function of time. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Subbaraman L, Jones L. In vitro wettability of a non-surface-modified silicone hydrogel contact lens material. 6th Canadian Optometry Conference on Vision Science, Waterloo, Ontario, 2007.

Caffery B, Joyce E, Slomovic A, Jones L, Simpson T. Tear volume and tear lipocalin ratios in Sjogrens, severe KCS and non-dry eye subjects. ISCLR meeting (Whistler, Canada), 2007.

Gorbet M, Jones L, Sheardown H. Corneal epithelial cell viability and integrin expression is affected by contact lens packaging solutions. ISCLR meeting, (Whistler, Canada), 2007.

Keir N, Subbaraman L, Woods C, Jones L, Fonn D. Clinical impact of pre-soaking a silicone hydrogel lens in a MPS care solution on a group of symptomatic wearers. ISCLR meeting (Whistler, BC, Canada), 2007.

Lorentz H, Rogers R, Jones L. In vitro deposition of lipid onto contact lens materials can lower contact angle wettability of surface-modified silicone hydrogel contact lens materials. ISCLR meeting, Whistler, BC, Canada, 2007.

Subbaraman L, Jones L. Activity of lysozyme deposited on conventional and silicone hydrogel contact lenses as a function of time. ISCLR meeting (Whistler, BC, Canada), 2007.

Luensmann D, Heynen M, Jones L. Confocal microscopy and albumin penetration into contact lenses. Optom Vis Sci 2007;84,9:839-847.

Subbaraman L, Jones L. Determination of lysozyme activity recovered from conventional and silicone hydrogel contact lenses as a function of time. University of Waterloo Graduate Student Research Conference, 2007.

2006

Subbaraman L, Jones L, Srinivasan S, Varikooty J, Glasier MA. Activity of lysozyme deposited on one-day etafilcon contact lenses is correlated with subjective comfort. Optom Vis Sci 2006;83:E-Abstract 060091.

Keir N, Dumbleton K, Jones L, Fonn D. A 12 month clinical comparison of continuous wear surface modified and non-surface modified silicone hydrogel contact lens materials. Optom Vis Sci 2006;83: E-Abstract 060070.

Luensmann D, Glasier MA, Zhang F, Jones L. A novel in vitro method to determine the penetration profile of albumin into silicone hydrogel and conventional hydrogel contact lens materials. Optom Vis Sci 2006;83:E-Abstract 060092.

Dumbleton K, Woods C, Jones L, Feng Y, Moezzi A, Fonn D. Comfort and adaptation to silicone hydrogel lenses for daily wear. Optom Vis Sci 2006;83: E-Abstract 060066.

Dumbleton K, Jones L, Woods C, Feng Y, Moezzi A, Fonn D. Clinical performance of a hydrogen peroxide care regimen with silicone hydrogel lenses. Optom Vis Sci 2006;83: E-Abstract 060069.

Srinivasan S, Joyce E, Jones L, Senchyna M. Tear osmolality and ferning patterns in postmenopausal women with and without symptoms of dry eye. Optom Vis Sci 2006;83: E-Abstract 060011.

Keir N, Feng Y, Dumbleton K, Woods C, Jones L, Simpson T, Fonn D, Cohen S, Potter W. The influence of a lubricant eye drop on ocular discomfort in symptomatic hydrogel contact lens wearers. Optom Vis Sci 2006;83: E-Abstract 065249.

Varikooty J, Srinivasan S, Subbaraman L, Feng Y, Jones L, Simpson T, Fonn D. The influence of pre-soaking single-use etafilcon contact lenses on ocular comfort in symptomatic and asymptomatic contact lens wearers. Optom Vis Sci 2006;83:E-Abstract 065245.

Srinivasan S, Varikooty J, Subbaraman L, Chan A, Woods C, Simpson T, Jones L, Fonn D. Atypical manifestation of upper lid margin staining in silicone hydrogel lens wearers with symptoms of dry eye. Optom Vis Sci 2006;83:E-Abstract 065255.

Keir N, Situ P, Richter D, Jones L, Fonn D. Clinical performance of alexidine-based and polyquad-based multipurpose solutions when used with daily wear etafilcon lenses. Optom Vis Sci 2006;83: E-Abstract 065232.

Subbaraman L, Glasier MA, Senchyna M, Sheardown H, Jones L. Lysozyme uptake kinetics on PMMA, FDA groups I, II, IV and first & second generation silicone hydrogel contact lens materials. Optom Vis Sci 2006;83:E-Abstract 065258.

Srinivasan S, Jones L, Joyce E, Simpson T, Senchyna M. Characterization of clinical signs and symptoms in asymptomatic and symptomatic dry eyed postmenopausal women. Optom Vis Sci 2006;83: E-Abstract 065201.

Jones D, Woods C, Jones L, Morgan P. The use of silicone hydrogel contact lenses by Canadian optometrists: 2000-2006. Optom Vis Sci 2006;83: E-Abstract 065281.

Woods J, Woods C, Varikooty J, Jones L, Simpson T, Fonn D. A novel method of recording corneal staining that facilitates parametric analysis. Optom Vis Sci 2006;83: E-Abstract 065236.

Dalton K, Rogers R, Jones L. Osmolality, pH, viscosity and surface tension of multi-purpose contact lens solutions. Optom Vis Sci 2006;83: E-Abstract 065236.

Suwala M, Glasier MA, Subbaraman L, Jones L. Quantity and conformation of lysozyme deposited on conventional and silicone hydrogel contact lens materials using an in vitro model. Optom Vis Sci 2006;83:E-Abstract 065259.

Bitton E, Keech A, Jones L. Overnight variation in tear ferning. Optom Vis Sci 2006;83: E-Abstract 065200.

Bitton E, Keech A, Simpson T, Jones L. Inter and intra observer variability in tear meniscus determined using OCT. Optom Vis Sci 2006;83: E-Abstract 065191.

Keir NJ, Simpson T, Jones L, Fonn D. Higher order aberration profiles differ for myopes and hyperopes before and 6 months after a CustomCornea LASIK procedure. Invest Ophthalmol Vis Sci 2006;47:E-Abstract 60.

Duench S, Simpson T, Jones L, Fonn D. Corneal staining is not correlated with limbal or bulbar redness in subjects using daily wear silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 87.

Srinivasan S, Jones L, Joyce E, Simpson T, Senchyna M. Clinical signs and symptoms in postmenopausal females with and without symptoms of dry eye. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 249.

Feng Y, Dumbleton K, Keir N, Woods CA, Jones L, Simpson T, Fonn D. The influence of a guar-based lubricant eye drop on ocular discomfort in symptomatic hydrogel contact lens wearers. Invest Ophthalmol Vis Sci 2006;47:ARVO E-Abstract 2381.

Sheardown H, Liu L, Jones L. Chemical characterization of 1-DAY ACUVUE® MOIST and 1-DAY ACUVUE Contact Lenses. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 2388.

Subbaraman LN, Jones L, Srinivasan S, Varikooty J, Glasier MA. Clinical signs & symptoms and protein deposition in one day wear of etafilcon lenses in symptomatic and asymptomatic subjects. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 2400.

Situ P, Simpson T, Jones L, Fonn D. Conjunctival and corneal sensitivity is associated with dry eye symptomatology. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 262.

Harvey KM, Simpson T, Jones L, Fonn D. The effects of silicone hydrogel contact lens wear on the corneal epithelium’s sub-basal nerve fibre layer. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 2393.

Dalton KN, Rogers R, Jones L. Physical properties of multi-purpose contact lens solutions. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 89.

Suwala M, Glasier MA, Jones L. Activity of lysozyme deposited on conventional and silicone hydrogel contact lens materials using an in vitro model. Invest Ophthalmol Vis Sci 2006;47:E-Abstract 108.

van Beek M, Sheardown H, Jones L. The effect of wetting agents on competitive protein adsorption to HEMA and HEMA/MA/PVP hydrogels. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 112.

Keech A, Joyce E, Senchyna M, Jones L. A rapid method for the extraction of mucin from hydrogel contact lenses. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 119.

Jones L. Contact lens solutions: Composition and function. 13th symposium on the Material Science and Chemistry of Contact Lenses (New Orleans, USA), 2006.

Haque S, Jones L, Simpson T. Mapping corneal & epithelial thickness using OCT: comparing neophytes, RGP lens wearers & keratoconics. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 1311.

Lorentz HI, Rogers R, Jones LW. In vitro deposition of lipid onto contact lens materials can lower contact angle wettability of surface-modified silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 2389.

Zhang F, Glasier MA, Sheardown H, Jones L. The use of confocal microscopy to determine the location of lysozyme deposition in conventional hydrogel and silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2006;47: E-Abstract 2405.

Jones L. Prescribing the best care system for the patient. British Contact Lens Association Annual Meeting, Birmingham, England,, 2006.

Jones L. The interface between lens and tears. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Rogers R, Jones L, Dalton K. Physical properties of multi-purpose contact lens solutions. Contact Lens & Anterior Eye 2006;29,4:189-190.

Rogers R, Jones L, Srinivasan S, Varikooty J, Fonn D. The influence of care regimen composition and wear time on ex vivo wettability of etafilcon contact lenses. Contact Lens & Anterior Eye 2006;29,4:189.

Glasier M, Keech A, Sheardown H, Corstorphine L, Jones L. Galyfilcon (Acuvue Advance) silicone hydrogel contact lenses deposit low levels of relatively active lysozyme. Contact Lens & Anterior Eye 2006;29,4:193.

Glasier M, Suwala M, Jones L. Activity of lysozyme deposited on conventional and silicone hydrogel contact lens materials using an in vitro model. Contact Lens & Anterior Eye 2006;29,4:193-194.

Lorentz H, Rogers R, Jones L. In vitro deposition of lipid onto contact lens materials can lower contact angle wettability of surface-modified silicone hydrogel contact lens materials. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Subbaraman L, Jones L, Srinivasan S, Varikooty J. Clinical signs & symptoms and protein deposition in one day wear of etafilcon lenses in symptomatic & asymptomatic subjects. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Keir N, Rogers R, Dumbleton K, Jones L, Fonn D. Comparision of ex-vivo wettability measurements of continuous wear surface treated and non-surface treated silicone hydrogel contact lens materials. Contact Lens & Anterior Eye 2006;29,4:195.

Zhang F, Glasier M, Sheardown H, Corstorphine, Jones L. Efficacy of multi-purpose contact lens solutions on passive lysozyme removal from silicone hydrogel and conventional hydrogel contact lenses. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Jones L, Sheardown H, Liu L, Croll A, Dalnoki-Varess K. A novel daily disposable contact lens with improved in-eye and end of day comfort. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Srinivasan S, Chan C, Jones L, Simpson T, Fonn D. Diurnal variation in interior tear meniscus height that occurs in dry-eyed and non-dry-eyed participants. British Contact Lens Association Annual Meeting, Birmingham, England, 2006.

Dalton K, Jones L. The performance of a novel nanolitre osmometer to investigate diurnal tear-film osmolality. Contact Lens & Anterior Eye 2006;29,4:204.

Subbaraman LN, Jones L, Srinivasan S, Varikooty J, Glasier M. The role of protein deposition and surface wettability in symptoms of contact lens-induced dryness during one day wear of etafilcon lenses in symptomatic and asymptomatic subjects. Contact Lens & Anterior Eye 2006;29,4:194-195.

Subbaraman LN, Glasier M, Senchyna M, Sheardown H, Jones L. Comparison of in vitro lysozyme uptake kinetics on PMMA, Conventional Hydrogel and First & Second generation Silicone Hydrogel contact lens materials. Contact Lens & Anterior Eye 2006;29,4:195.

Subbaraman LN, Glasier MA, Srinivasan S, Varikooty J, Jones L. Correlation between clinical signs & symptoms and protein deposition in one day wear of etafilcon lenses in symptomatic and asymptomatic subjects. University of Waterloo Graduate Student Research Conference, 2006.

Varikooty J, Srinivasan S, Subbaraman L, Chan A, Woods C, Jones L, Simpson T, Fonn D. Clinical manifestations of upper lid staining in adapted silicone hydrogel lens wearers. Optom Vis Sci 2006;83:E-abstract 065256.

Jones L, Keir N, Situ P, Fonn D. The impact of post–insertion time on corneal staining and comfort with Group II hydrogel materials. 13th Symposium on the Materials Science and Chemistry of Contact Lenses (New Orleans, USA), 2006.

Zhang F, Glasier MA, Sheardown H, Jones L. The use of confocal microscopy to determine the location of lysozyme deposition in conventional hydrogel and silicone hydrogel contact lens materials. 13th Symposium on the Materials Science and Chemistry of Contact Lenses (New Orleans, USA), 2006.

Subbaraman LN, Glasier MA, Senchyna M, Sheardown H, Jones L. Comparison of in vitro lysozyme uptake kinetics on PMMA, Conventional Hydrogel and First & Second generation Silicone Hydrogel contact lens materials. Biomaterials meeting (New Orleans, USA), 2006.

Subbaraman L, Glasier M, Senchyna M, Sheardown H, Jones L. Comparison of the in vitro lysozyme uptake kinetics on PMMA, conventional hydrogel and first and second generation silicone hydrogel contact lens materials. 13th Symposium on the Materials Science and Chemistry of Contact Lenses (New Orlean, USA), 2006.

Suwala M, Glasier M, Subbaraman LN, Jones L. Quantity and conformation of lysozyme deposited on conventional and silicone hydrogel contact lens materials using an in vitro model. Biomaterials meeting (New Orleans, USA), 2006.

Dalton KN, Rogers R, Jones L. Physical properties of multi-purpose contact lens solutions. 13th Symposium on the Materials Science and Chemistry of Contact Lenses (New Orleans, USA), 2006.

Zhang F, Glasier MA, Sheardown H, Corstorphine L, Jones L. Efficacy of multi-purpose contact lens solutions on passive lysozyme removal from silicone hydrogel and conventional hydrogel contact lenses. 13th Symposium on the Materials Science and Chemistry of Contact Lenses (New Orleans, USA), 2006.

Haque S, Jones L, Simpson T. Mapping corneal and epithelial thickness using OCT: Comparing neophytes, RGP lens wearers and keratoconics. Canadian Student Health Research Forum (Winnipeg, Canada), 2006.

Subbaraman L, Jones L, Srinivasan S, Varikooty J, Glasier MA. The relationship between protein deposition and clinical signs and symptoms in one day wear of etafilcon lenses in symptomatic and asymptomatic subjects. Canadian Student Health Research Forum (Winnipeg, Canada), 2006.

Keir N, Rogers R, Dumbleton K, Jones L, Fonn D. Comparison of ex vivo wettability measurements of continuous wear surface treated and non-surface treated silicone hydrogel contact lens materials. British Contact Lens Association Annual Meeting (Birmingham, England), 2006.

Zhang F, Gu Y, Pawliszyn J, McMahon T, Jones L. Bioanalytical analysis of non-polar lipids in human tears using LC/MS. American Society for Mass Spectrometry Conference (Seattle, USA), 2006.

Duench S, Sorbara L, Simpson TL, Jones L, Fonn D. The use of fluorophotometry to measure corneal epithelial permeability to contact lenses and contact lens care regimens. Optom Vis Sci 2006;83:E-Abstract 65238.

2005

Duench S, Simpson T, Jones L, Flanagan J, Fonn D. Assessment of the diurnal relationship between bulbar conjunctival redness, temperature and blood flow. Optom Vis Sci 2005;82: E-Abstract 055003.

Situ P, Simpson T, Jones L, Fonn D, Vehige J, Simmons P. The association between corneal & conjunctival sensitivity, tear film stability & ocular surface appearance in subjects with & without dry eye symptoms. Optom Vis Sci 2005;82: E-Abstract 050066.

Dalton K, Jones L. The performance of a novel nanolitre osmometer to investigate diurnal tear film osmolality. Optom Vis Sci 2005;82: E-abstract 055071.

Glasier MA, Keech A, Sheardown H, Corstorphine L, Jones L. Galyfilcon (Acuvue Advance) silicone hydrogel contact lenses deposit low levels of relatively active lysozyme. Optom Vis Sci 2005;82:E-abstract 055109.

Haque S, Fonn D, Simpson T, Jones L. Corneal, stromal and epithelial thickness changes following overnight CRT, comparing two high-Dk lens materials. Optom Vis Sci 2005;82: E-abstract 050041.

Keir N, Situ P, Richter D, Jones L, Sijpson T, Fonn D. Impact of post-insertion time on corneal staining, sensitivity and comfort with an FDA group II lens disinfected with various care regimens. Optom Vis Sci 2005;82: E-abstract 055103.

Srinivasan S, Chan C, Jones L, Simpson T, Fonn D. Diurnal variation in inferior tear meniscus height that occurs in dry eyed and non-dry eyed participants. Optom Vis Sci 2005;82: E-abstract 050064.

Subbaraman L, Glasier MA, Senchyna M, Jones L. Kinetics of 1251-labelled lysozyme deposition on silicone hydrogel, FDA group II and group IV contact lenses. Optom Vis Sci 2005;82:E-abstract 050046.

Varikooty J, Situ P, Jones L, Fonn D. Clinical performance of alexidine-based and polyquad-based multipurpose solutions when used with daily wear balafilcon lenses. Optom Vis Sci 2005;82: E-abstract 055100.

Vehige J, Simmons P, Feng Y, Situ P, Simpson T, Jones L, Fonn D. Does the subjective evaluation of symptoms of dryness (SESoD) as a single variable predict the severity of signs and symtpoms of dry eye disease?. Optom Vis Sci 2005;82: E-abstract 050067.

Woods C, Jones D, Jones L, Morgan P. Canadian optometrists prescribing habits, a six-year period (2000-05). Optom Vis Sci 2005;82: E-abstract 055128.

Zhang F, Glasier MA, Sheardown H, Corstorphine L, Jones L. Efficacy of multi-purpose contact lens solutions on passive lysozyme removal from silicone hydrogel and conventional hydrogel contact lenses . Optom Vis Sci 2005;82. [ Show Abstract ]

E-abstract 055098

Jones L. Risks and benefits of refractive surgery vs. silicone hydrogels. 2nd Asia Cornea & Contact Lens Conference, Hong Kong Polytechnic University (Hong Kong, China), 2005.

Keir N, Simpson T, Jones L, Fonn D. Factor analysis of postoperative outcome variables for a CustomCornea(R) LASIK clinical trial. Invest Ophthalmol Vis Sci 2005;46: E-abstract 4352.

Jones L, Keir N, Situ P, Fonn D. The impact of post-insertion time on corneal staining and comfort with Group II hydrogel mateials disinfected with various lens care regimens. Invest Ophthalmol Vis Sci 2005;46: E-abstract 917.

Liu L, Jones L, Sheardown H. Wetting agent release from contact lenses. Invest Ophthalmol Vis Sci 2005;46: E-abstract 908.

Princz MA, Jones L, Sheardown H. Release of wetting agents from Nelfilcon contact lenses. Invest Ophthalmol Vis Sci 2005;46: E-abstract 907.

Rogers R, Jones L. In vitro and ex vivo wettability of pHEMA and siloxane-based contact lens polymers . Invest Ophthalmol Vis Sci 2005;46: E-abstract 918.

Situ P, Simpson TL, Jones L, Fonn D. Effect of symptoms of dryness, age, and gender on corneal and conjunctival sensitivity to cooling stimuli. Optom Vis Sci 2005;46: E-abstract 4448.

Srinivasan S, Heikkila E, Kyveris A, Senchyna M, Jones L. Method optimization for the isolation of total protein from human conjunctival epithelial cells collected via impression cytology. Invest Ophthalmol Vis Sci 2005;46: E-abstract 2667.

Subbaraman LN, Glasier MA, Senchyna M, Jones L. Kinetics of in vitro lysozyme deposition on silicone hydrogel, group II and group IV contact lens materials. Invest Ophthalmol Vis Sci 2005;46:E-abstract 910.

Vaccari S, Simpson T, Jones L, Flanagan J, Fonn D. The assessment of diurnal variation of bulbar conjunctival hyperemia, temperature and conjunctival blood flow before and after sleep. Invest Ophthalmol Vis Sci 2005;46; E-abstract 2681.

Jones L, Srinivasan S, Varikooty J, Simpson T. Novel methodologies to investigate patients with symptoms of dry eye. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L. It's all in the surface. British Contact Lens Association Annual Meeting (Brighton, England), 2005.

Jones L. Differential diagnosis of a red eye. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L, Ngai V, Medley J. Measurement of friction associated with lotrafilcon and polyHEMA hydrogel contact lenses. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L. A contact lens fairy tale. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L, Sheardown H. In vitro absorption of radiolabelled albumin and lysozyme from mixed protein solutions to contact lens materials. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L, Keir N, Situ P, Fonn D. The impact of post-insertion time on corneal staining and comfort with group II hydrogel materials disinfected with various lens care regimens. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Jones L, Teichroeb J, Forrest J, Ngai V, Martin J, Medley J. Imaging protein deposits on silicone hydrogel contact lens materials. British Contact Lens Association Annual Meeting, Brighton, England, 2005.

Rogers R, Jones L. In vitro and ex vivo wettability of pHEMA and siloxane-based contact lens polymers . Canadian Biomaterials Society (Waterloo, Ontario), 2005.

Ngai V, Medley JB, Jones L, Forrest J, Teichroeb J. Friction simulation of the anterior surface of hydrogel contact lenses. Canadian Biomaterials Society (Waterloo, Ontario), 2005.

Subbaraman L, Senchyna M, Jones L. Determination of in vitro lysozyme uptake kinetics on silicone hydrogel, FDA group II and FDA group IV hydrogel contact lens materials. 24th Canadian Biomaterials Society Conference (Waterloo, Ontario), 2005.

Teichroeb J, Ngai V, Forrest J, Jones L. Thermal stability of lysozyme adsorbed onto gold nanoparticles. Canadian Biomaterials Society (Waterloo, Ontario), 2005.

Jones L. Surface properties of silicone hydrogels. International Society for Contact Lens Researchers (ISCLR) Conference (Coolum, Australia), 2005.

Subbaraman L, Senchyna M, Jones L. Kinetics of 1251-labelled lysozyme deposition on silicone hydrogel FDA Group II and Group IV contact lenses. 13th Scientific Meeting of the International Society for Contact Lens Research, Coolum, Australia, 2005.

Ngai V, Medley JB, Jones L, Forrest J, Teichroeb J. Friction of contact lenses: silicone hydrogel versus conventional hydrogel. Tribology and Interface Engineering Series 2005;48371-379.

Harvey K, Jones L, Simpson T. Using confocal microscopy to investigate the corneal epithelium. Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Keir N, Simpson T, Jones L, Fonn D. Factor analysis of postoperative outcome variables for a CustmCornea LASIK clinical trial. Graduate Student Research Conference( University of Waterloo, Ontario), 2005.

Rogers R, Jones L. In vitro and ex vivo wettability of pHEMA and siloxane-based contact lens polymers. Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Subbaraman L, Glasier M, Senchyna M, Jones L. Determination of lysozyme deposition on silicone hydrogel, group II and group IV contact lenses as a function of time. Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Situ P, Simpson T, Jones L. Association between corneal and conjunctival sensitivity, tear film stability and ocular surface appearance in subjects with and without dryness symptoms. Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Srinivasan S, Jones L, Senchyna M. Comparison of bulbar conjunctival hyperemia in postmenopausal dry eyed and non-dry eyed subjects. Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Teichroeb J, Forrest J, Jones L. Protein deposition onto implantable biomaterials measured with Quartz Crystal Microblanace (QCM). Graduate Student Research Conference (University of Waterloo, Ontario), 2005.

Subbaraman L, Glasier M, Senchyna M, Jones L. An in vitro comparison of the kinetics of lysozyme deposition on silicone hydrogel, group II and group IV contact lens materials. Graduate Student Research Conference, University of Waterloo, Ontario, 2005.

Subbaraman LN, Jones L, Srinivasan S, Varikooty J, Glasier M. The relationship between protein deposition and clinical signs & symptoms in one day wear of etafilcon lenses in symptomatic and asymptomatic subjects. Canadian Student Health Research Forum, 2005.

Subbaraman LN, Glasier MA, Senchyna M, Jones L. An in vitro comparison of the lysozyme uptake kinetics on first & second generation silicone hydrogel and conventional hydrogel contact lens materials. Institute for Ocular Biomaterials Research Meeting (Hamilton, Ontario), 2005.

Subbaraman L, Glasier M, Senchyna M, Jones L. An in vitro comparison of the kinetics of lysozyme deposition on silicone hydrogel, group II and group IV contact lens materials. British Contact Lens Association Annual Meeting (Brighton, England), 2005.

2004

Dumbleton K, Keir N, Moezzi A, Jones L, Fonn D. Redness, dryness and comfort following refitting long-term low Dk lens wearers with silicone hydrogel lenses. Optom Vis Sci 2004;81,12s:31.

Jones L, Bayer S, Senchyna M, Subbaraman L, Glasier M, Dumbleton K, Fonn D. Rewetting drops influence comfort and protein deposition on silicone hydrogel contact lenses. Optom Vis Sci 2004;81,12s:57.

Haque S, Jones L, Simpson T. Corneal and epithelial thickness in keratoconus: a comparison of ultrasonic pachymetry, orbscan and optical coherence tomography measurements. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 2891.

Jones L, Rahman S, Leech R, Simpson T, Fonn D. Determination of inferior tear meniscus height and inferior tear meniscus volume using optical coherence tomography . Invest Ophthalmol Vis Sci 2004;45: E-Abstract 144.

Bayer S, Jones LW, Senchyna M, Subbaraman L, Glasier M, Dumbleton K, Fonn D. Effect of rewetting drops on comfort and protein deposition of silicone hydrogel (Focus Night&Day) contact lenses. Invest Ophthalmol Vis Sci 2004;45,4:s65.

Srinivasan S, Senchyna M, Heikkila L, Jones L. Method optimization for the isolation of total RNA from human conjunctival epithelial cells collected via impression cytology. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 1500.

Glasier MA, Senchyna M, Jones L, Mahabir N. Method optimization for the quantification of total protein deposited on silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2004;45; E-Abstract 1583.

Teichroeb J, Forrest J, Ngai V, Martin J, Jones L, Medley J. Imaging protein deposits on silicone hydrogel contact lens materials. Optom Vis Sci 2004;81,12s:83.

Lorentz H, Senchyna M, Jones L. Optimized procedure for the extraction of lipid deposits from silicone hydrogel contact lenses. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 1537.

Srinivasan S, Jones L, Senchyna M. Comparison of bulbar conjunctival hyperemia in postmenopausal dry eyed and non dry eyed subjects. Optom Vis Sci 2004;81,12s:213.

Senchyna M, Heikkila E, Vehige J, Simmons P, Jones L, Bornstein M. Relative quantitation of major basic protein species found in the human tear film. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 4831.

Dumbleton K, Jones L, Bayer S, Fonn D. Clinical performance and corneal staining associated with silicone hydrogel materials used on a daily wear basis. Contact Lens & Anterior Eye 2004;27,2:97-98.

Subbaraman LN, Senchyna M, Jones L. Stabilization of lysozyme mass extracted from silicone hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2004;45:ARVO E-Abstract 1556.

Dumbleton K, MacDougall N, Jones L, Moezzi A, Fonn D, McNally J. Changes in hyperemia subsequent to refitting long-term low Dk wearers with silicone hydrogel lenses on a daily wear basis. Contact Lens & Anterior Eye 2004;27,2:102.

Varikooty JP, Simpson TL, Jones LW, Fonn D. Subjective sensations reported during the interblink interval reflect different components of ocular surface sensitivity. Invest Ophthalmol Vis Sci 2004;45: E-abstract 99.

Lu FU, Simpson TL, Sorbara L, Fonn D, Jones LW. The relationship between treatment zone diameter and visual, optical and subjective performance in CRT(TM) wearers. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 1576.

Vaccari S, Simpson T, Jones L, Fonn D. Assessment of diurnal variation of bulbar conjunctival hyperemia using a novel objective method. Invest Ophthalmol Vis Sci 2004;45: E-Abstract 4828.

Jones L, Bayer S, Dumbleton K, Fonn D. Corneal staining associated with silicone hydrogel materials used on a daily wear basis with ReNu and AOSept care regimens. International American Academy Meeting (Hawaii), 2004.

Bayer S, Jones L, Senchyna M, Subbaraman L, Glasier M, Dumbleton K, Fonn D. Effect of rewetting drops on comfort and protein deposition of silicone hydrogel (Focus Night & Day) contact lenses. Invest Ophthalmol Vis Sci 2004;45ARVO E-Abstract 1575.

Subbaraman LN, Senchyna M, Jones L. Stabilization of lysozyme mass extracted from silicone hydrogel contact lens materials. Graduate Student Research Conference (University of Waterloo, Ontario), 2004.

Teichroeb J, Forrest J, Ngai V, Martin J, Jones L, Medley J. In situ imaging of in vitro deposited lysozyme and albumin on silicone hydrogel and Hema contact lens materials. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Sheardown H, Jones L. In vitro adsorption of albumin and lysozyme from mixed protein solutions to commercial contact lenses. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Jones L, Senchyna M, Glasier MA. Quantification and conformational state of lysozyme deposition on daily wear etafilcon, balafilcon and lotrafilcon contact lens materials. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Ngai V, Medley J, Jones L. Measurement of friction associated with lotrafilcon and HEMA hydrogel contact lenses. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Feng Y, Situ P, Jones L, Simpson T. Tear meniscus height is a poor predictor of ocular dryness symptoms. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Srinivasan S, Jones L, Senchyna M. Comparison of non-invasive tear break up time and bulbar conjunctival hyperemia in postmenopausal dry-eyed and non dry-eyed subjects. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Jones L, Rahman S, Leech R, Simpson T, Fonn D. Determination of inferior tear meniscus height and volume using optical coherence tomography. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Fonn D, Jones L, Chan A. Corneal staining does not affect the comfort of soft contact lens wear. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Simpson T, Situ P, Jones L. Association between corneal and conjunctival sensitivity, tear film stability and ocular surface appearance in subjects with and without dryness symptoms. Tear Film and Ocular Surface Society (Puerto Rico), 2004.

Dalton K, Teichroeb J, Chan J, Forrest J, Jones L. Study of protein deposition on hydrogels with QCM technology. Waterloo-Guelph Physics Conference (Guelph, Ontario), 2004.

Jones L, Senchyna M, Glasier MA. Quantification and conformational state of lysozyme deposition on daily wear etafilcon, balafilcon and lotrafilcon contact lens materials. 7th World Biomaterials Conference (Sydney, Australia), 2004.

Jones L, Schickler J, Sorbara L, Dumbleton K, Keir N, Bayer S. Corneal staining with FDA group II and silicone hydrogel contact lens materials used with PHMB-based disinfection systems. 7th World Biomaterials Conference (Sydney, Australia), 2004.

Ngai V, Medley JB, Jones L. Friction of contact lenses: Silicone and conventional hydrogels. 7th World Biomaterials Conference (Sydney, Australia), 2004.

Sheardown H, Jones L. In vitro adsorption of albumin and lysozyme from mixed protein solutions to commercial contact lenses. 7th World Biomaterials Conference (Sydney, Australia), 2004.

2003

MacDougall N, Situ P, Chan A, Simpson T, Jones L, Fonn D, Hakim O. Low contrast acuity, contrast sensitivity and higher order aberration outcomes following Custom LASIK. Invest Ophthalmol Vis Sci 2003;44: E-Abstract 2629.

Sorbara L, MacDougall N, Situ P, Chan A, Hakim O, Fonn D, Jones L, Simpson T. Relationship between corneal shape and refractive power pre- and post-Custom LASIK. Invest Ophthalmol Vis Sci 2003;44: E-Abstract 2615.

Senchyna M, Jones L, Glasier M, Dumbleton K, Bayer S. The influence of peroxide-based versus a polyhexanide-based MPS in controlling the quantity and conformation of deposited lysozyme on silicone-hydrogel contact lenses. Invest Ophthalmol Vis Sci 2003;44: E-Abstract 3688.

Lu F, Sorbara L, Kort RA, Fonn D, Simpson T, Jones L. Topographic keratometric effects of corneal refractive therapy after one night of lens wear. Invest Ophthalmol Vis Sci 2003;44: E-Abstract 3699.

Jones L, Dumbleton K, Woods C, Joseph J. Practitioner perspectives towards recommendation of daily disposable and continuous wear lenses: a global view. Contact Lens & Anterior Eye 2003;26,2:105.

Senchyna M, Glasier M, Jones L, Dumbleton K. Assessing the degree of denatured lysozyme deposited on conventional and silicone hydrogel contact lenses. Contact Lens & Anterior Eye 2003;26,4:206.

Jones L, Rahman S, Leech R, Simpson T, Fonn D, Vehige JG, Simons PA. Determination of tear meniscus height using a novel method based upon Optical Coherence Tomography. Invest Ophthalmol Vis Sci 2003;44: E-Abstract 2461.

Karlgard C, Jones L, Sarkar D, Leung T, Moresoli C. XPS characterization of soft contact lens materials. Contact Lens & Anterior Eye 2003;26,4:206.

Jones L, Rahman S, Leech R, Simpson T, Fonn D. The use of optical coherence tomography to determine tear volume. International Society for Contact Lens Research (Mallorca, Spain), 2003.

Jones L. Ocular compatibility of silicone hydrogel contact lens materials. MMO/EMK Research Day in Biointerfaces (McMaster University, Canada), 2003.

Lu F, Sorbara L, Kort RA, Fonn D, Simpson T, Jones L. Effects of corneal shape after one night of CRT lens wear. University of Waterloo Graduate Research Conference Handbook, 2003.

MacDougall N, Situ P, Chan A, Fonn D, Simpson TL, Jones L, Hakim O. Quality of vision outcomes following custom LASIK. University of Waterloo Graduate Research Conference Handbook, 2003.

Jones L, Leech R, Rahman S, Simpson T, Fonn D. A novel method to determine tear prism height. Contact Lens & Anterior Eye 2003;26,4:206-207.

Jones L, Dumbleton K, Fonn D, Dillehay S. Comfort and compliance with frequent replacement soft contact lenses in North America: a survey. Contact Lens & Anterior Eye 2003;26,4:205-206.

Lu F, Simpson T, Jones L. Repeatability of Orbscan II pachymetry measures. Optom Vis Sci 2003;80,12s:100.

Haque S, Jones L, Fonn D, Simpson T, Sorbara L. Changes in topographical thickness of the total cornea following 4 weeks of overnight CRT RGP lens wear measured with OCT. Optom Vis Sci 2003;80,12s:243.

Jones L, Rahman S, Leech R, Simpson T, Fonn D, Vehige J, Simmons P. Determination of tear meniscus height using a novel method based upon optical coherence tomography. BCLA Conference (Brighton, England), 2003.

2002

Jones L, Senchyna M, Forbes I, May C. The influence of multipurpose care regimens in controlling lysozyme deposition on Etafilcon contact lenses. Contact Lens & Anterior Eye 2002;25,4:211.

Wang J, Fonn D, Simpson T, Jones L. The measurement of corneal epithelial thickness using the OCT in response to hypoxia induced by soft contact lens and eye closure. Contact Lens & Anterior Eye 2002;25,1:36.

Karlgard C, Jones L, Moresoli C. Uptake and release of Acular from silicone-hydrogel and conventional hydrogel contact lens materials. Contact Lens & Anterior Eye 2002;25,1:38.

Karlgard C, Wong N, Jones L, Moresoli C. Uptake and release of topical ocular pharmaceuticals from silicone-hydrogel and conventional hydrogel contact lenses in vitro. Contact Lens & Anterior Eye 2002;25,4:208.

Jones L. Visual acuity and visual performance: an update on its measurement. Contact Lens & Anterior Eye 2002;25,4:182.

Karlgard C, Sarkar DK, Leung KT, Jones L, Moresoli C. Surface characterization of silicone hydrogel contact lens materials. Canadian Biomaterials Society Annual Conference, Toronto, Canada, 2002.

Jones L, Senchyna M, Louie D, May C, Schickler J. A comparative evaluation of lysozyme and lipid deposition on Etafilcon, Balafilcon and Lotrafilcon contact lens materials. Society for Biomaterials, Trans 28th Ann Clin Conf (Tampa, Florida), 2002.

Karlgard C, Jones L, Moresoli C. Ciprofloxacin interaction with silicone hydrogel contact lenses. Society for Biomaterials, Trans 28th Ann Clin Conf, Tampa, Florida, 2002.

Karlgard C, Jones L, Moresoli C. Deposition of ocular pharmaceutical agents onto silicone hydrogel contact lens materials. Society for Biomaterials, Trans 28th Ann Clin Conf, Tampa, Florida, 2002.

Karlgard C, Sarkar DK, Leung KT, Jones L, Moresoli C. Sample preparation of soft contact lenses for surface analysis by XPS. Surface Science Canada 2002, University of Ottawa, Canada, 2002.

Karlgard C, Wong NS, Jones L, Moresoli C. Drug interactions with soft contact lenses. University of Waterloo Graduate Research Conference, Waterloo, Ontario, 2002.

Jones L. Novel contact lens materials: What problems remain?. Contact Lens & Anterior Eye 2002;25,4:179.

Edwards K, Jones L. Torics without tears. Contact Lens & Anterior Eye 2002;25,1:25.

Jones L, Dumbleton K, MacDougall N, Fonn D. Subjective comfort with daily wear of silicone hydrogel contact lenses. CIBA-Vision Educators Meeting abstract book (Atlanta, Georgia), 2002.

Dumbleton K, MacDougall N, Jones L, Simpson T, Fonn D. Patient satisfaction with continuous wear contact lenses versus LASIK. CIBA-Vision Educators Meeting abstract book (Atlanta, Georgia), 2002.

Jones L, Dumbleton K, Fonn D. A survey to determine the patient comfort and compliance with different contact lens replacement schedules. CIBA-Vision Educators Meeting abstract book (Atlanta, Georgia), 2002.

Jones L, Senchyna M, Dumbleton K. Ocular biocompatibility of silicone-hydrogel contact lens materials. 1st World Summit on Silicone-Hydrogel Contact Lenses (San Diego, California), 2002.

Jones L, May C, Nazar L, Simpson T. In vitro evaluation of the dehydration characteristics of silicone-hydrogel and conventional hydrogel contact lens materials. Society of Biomaterials, 28th Annual Conference (Tampa, Florida), 2002.

Dumbleton K, Jones L. Managing Continuous Wear Adverse Events. Night and Day Clinical Council Symposium (Atlanta, Georgia), 2002.

Jones L, Leech R, Rahman S, Simpson T, Fonn D. A novel method to determine tear prism height. Optom Vis Sci 2002;79,12s:252.

Senchyna M, Glasier M, Thorogood N, Jones L, Dumbleton K. Assessing the degree of denatured lysozyme deposited on conventional and silicone-hydrogel contact lenses. Optom Vis Sci 2002;79,12s:135.

Jones L, Dumbleton K, Fonn D, Dillehay S. Comfort and compliance with frequent replacement soft contact lenses. Optom Vis Sci 2002;79,12s:259.

MacDougall N, Situ P, Chan A, Fonn D, Jones L, Simpson T. Comparison between orbscan and ultrasound central corneal thickness measurements. Optom Vis Sci 2002;79,12s:264.

Dumbleton K, Jones L, MacDougall N, Simpson T, Fonn D. Patient satisfaction with silicone hydrogel continuous wear contact lenses. Optom Vis Sci 2002;79,12s:8.

Jones L, Dumbleton K, Woods C, Joseph J. Practitioner perspectives towards recommendation of daily disposable and continuous wear lenses: a global view. Optom Vis Sci 2002;79,12s:6.

MacDougall N, Situ P, Chan A, Fonn D, Jones L, Simpson T. Single site 6-month clinical outcomes for custom LASIK. Optom Vis Sci 2002;79,12s:173.

Jones L, Sarkar D, Leung T, Moresoli C. XPS characterization of soft contact lens materials. Optom Vis Sci 2002;79,12s:134.

Varikooty J, Simpson T, Jones L, Fonn D. Ocular discomfort during tear film drying. Invest Ophthalmol Vis Sci 2002;43: E-abstract 3106.

Senchyna M, Jones L, Louie D, Forbes I, May C. Optimization of methodologies to characterise lysozyme deposition found on balafilcon and etafilcon contact lens materials. Invest Ophthalmol Vis Sci 2002;43: E-abstract 3082.

Wang JH, Fonn D, Simpson TL, Jones L. Pre-corneal and pre- and post-lens tear film thickness measured with optical coherence tomography. Invest Ophthalmol Vis Sci 2002;43: E-abstract 3078.

Jones L, Long J, Chen P. The impact of contact lens care regimens on the in vitro wettability of conventional and silicone-hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2002;43; E-abstract 3097.

Jones L, Senchyna M, Louie D, May C, Schickler J. A comparative evaluation of lysozyme and lipid deposition on Etafilcon, Balafilcon and Lotrafilcon contact lens materials. Contact Lens & Anterior Eye 2002;25,1:38.

Jones L, Cheng A, Woods C, Levitt L. Frequency of follow-up in asymptomatic contact lens wearers: reaching a consensus view. Contact Lens & Anterior Eye 2002;25,1:39.

Jones L. In vitro evaluation of the dehydration characteristics of silicone-hydrogel and conventional hydrogel contact lens materials. Contact Lens & Anterior Eye 2002;25,1:27.

Senchyna M, Louie D, Meadows E, Jones L. Quantification of sIgA concentration in tears of dry eye and non-dry eye individuals. Contact Lens & Anterior Eye 2002;25,1:38.

Jones L, MacDougall N, Sorbara L, Fonn D. The clinical performance of a polyquad-based care regimen with a silicone-hydrogel material used on a daily wear basis. Contact Lens & Anterior Eye 2002;25,4:211.

2001

Sorbara L, Machalitza A, Simpson T, Jones L, Fonn D. Is tear turnover rate measured by fluorophotometry a valuable tool in identifying dry eye patients?. Invest Ophthalmol Vis Sci 2001;42,4:s39 #218.

Jones L. Contact lens materials: A practitioner’s viewpoint. New Zealand Contact Lens Society (Blenheim, New Zealand), 2001.

Karlgard C, Jones L, Moresoli C. Uptake and release of Ciprofloxacin from silicone-hydrogel and conventional hydrogel contact lens materials. 12th Symposium on the Material Science and Chemistry of Contact Lens Materials, New Orleans, 2001.

Varikooty JP, Simpson TL, Jones L, Fonn D. Ocular discomfort during tear drying: A method to simultaneously acquire discomfort ratings, ocular surface video and sensation attributes on a pseudocontinuous scale. Invest Ophthalmol Vis Sci 2001;42,4:s941 #5038.

Karlgard C, Jones L, Moresoli C. Uptake and release of topical ophthalmic pharmaceuticals from silicone-hydrogel and conventional hydrogel contact lens materials. International Society for Contact Lens Research (Sun Valley, Idaho), 2001.

Jones L, May C, Nazar L. In vitro evaluation of the dehydration characteristics of silicone-hydrogel and conventional hydrogel contact lens materials. 12th Symposium on the Material Science and Chemistry of Contact Lens Materials (New Orleans), 2001.

MacDougall N, Sorbara L, Jones L, Fonn D. The clinical performance of a polyquad-based care regimen with a silicone-hydrogel material used on a daily wear basis. Optom Vis Sci 2001;78,12s:309.

Jones L, Senchyna M, Louie D, Schickler J. A comparative evaluation of lysozyme and lipid deposition on Etafilcon, Balafilcon & Lotrafilcon contact lens materials. 12th Symposium on the Material Science and Chemistry of Contact Lens Materials (New Orleans), 2001.

Senchyna M, Jones L, Forbes I, May C, MacDougall N, Sorbara L. The influence of multipurpose care regimens in controlling lysozyme deposition on Etafilcon contact lenses. Optom Vis Sci 2001;78,12s:308.

Karlgard C, Jones L, Moresoli C. Uptake and release of Ciloxan from silicone-hydrogel and conventional hydrogel contact lens materials. Optom Vis Sci 2001;78,12s:202.

Jones L, Senchyna M, Louie D, Schickler J. A comparative evaluation of lysozyme and lipid deposition on Etafilcon, Balafilcon & Lotrafilcon contact lens materials. Invest Ophthalmol Vis Sci 2001;42: E-abstract 3186.

Hartwick A, Oriowo O, Jones L, Sivak J. In vitro ocular Irritancy of multipurpose contact lens solutions. Invest Ophthalmol Vis Sci 2001;42:ARVO Abstract 3184.

Senchyna M, Louie D, Meadows E, Jones L. Quantification of sIgA concentration in tears of dry eye and non-dry eye individuals. Invest Ophthalmol Vis Sci 2001;42,4:s37 #211.

Wang J, Fonn D, Simpson T, Jones L. Tear film thickness measured with optical coherence tomography. International Society for Contact Lens Research, Sun Valley, Idaho, 2001.

Karlgard C, Jones L, Moresoli C. Uptake and release of Ciloxan from silicone-hydrogel and conventional hydrogel contact lens materials. Invest Ophthalmol Vis Sci 2001;42: E-abstract 3179.

Dumbleton K, Fonn D, Jones L, Williams-Lyn D, Richter D. Severity and management of contact lens related complications with continuous wear of high Dk silicone hydrogel lenses. BCLA Conference, Brighton, England, 2001.

Varikooty JP, Simpson TL, Jones L, Fonn D. Ocular discomfort during tear drying. International Society for Contact Lens Research, Sun Valley, Idaho, 2001.

2000

Jones L, Louie D, Senchyna M, Dumbleton K, Sorbara L. A comparative evaluation of lysozyme deposition on Etafilcon & silicone-hydrogel contact lens materials. Optom Vis Sci 2000;77,12s:176.

Jones L, Senchyna M, Louie D, May C, Dumbleton K. A comparative evaluation of IgA and lysozyme deposition on Etafilcon and Lotrafilcon contact lens materials. Contact Lens & Anterior Eye 2000;23,4:175.

Jones L, Senchyna M, Louie D, May C, Schubert N, Dumbleton K. A comparative evaluation of IgA and lysozyme deposition on Etafilcon and Lotrafilcon contact lens materials. Invest Ophthalmol Vis Sci 2000;41: E-abstract 368.

Jones L . Continuous wear contact lenses: Practical considerations. International Symposium on Eye & Vision (Montreal, Canada), 2000.

Jones L. High Dk hydrogel contact lenses: The facts. Danish Opthalmology Meeting (Copenhagen, Denmark), 2000.

Jones L. Extended wear contact lenses: A historical perspective. Danish Opthalmology Meeting (Copenhagen, Denmark), 2000.

Jones L. Mucin ball development in high Dk hydrogel contact lenses. BCLA Conference (Birmingham, UK), 2000.

Chan M, Louie D, Senchyna M, Jones L. Inter- and intra-subject variability in IgA levels within the tear film of non-contact lens wearers. Optom Vis Sci 2000;77,12s:265.

Jones L, Cheng A, Woods C, Levitt L. Frequency of follow-up in asymptomatic contact lens wearers: reaching a consensus view. Optom Vis Sci 2000;77,12s:119.

May C, Jones L, Nazar L, Simpson T. In vitro evaluation of the dehydration characteristics of silicone-hydrogel and conventional hydrogel contact lens materials. Optom Vis Sci 2000;77,12s:215.

Louie D, Senchyna M, Jones LW, May C, Dumbleton K. Lysozyme deposition and removal from a high Dk silicone hydrogel contact lens material: a comparison of 7 day vs 30 day wear. Optom Vis Sci 2000;77,12s:177.

Dumbleton K, Fonn D, Jones L, Williams-Lyn D, Richter D. Severity and management of contact lens related complications with continuous wear of high Dk silicone hydrogel lenses. Optom Vis Sci 2000;77,12s:216.

Wang J, Fonn D, Simpson T, Jones L. The measurement of corneal epithelial thickness using the OCT in response to hypoxia induced by soft contact lens and eye closure. Optom Vis Sci 2000;77,12s:170.

Morgan P, Efron N, Helland M, Jones L, van der Worp E, Woods C. Trends in international contact lens prescribing 2000. Optom Vis Sci 2000;77,12s:258.

Karlgard C, Jones L, Moresoli C. Uptake and release of Acular from silicone-hydrogel and conventional hydrogel contact lens materials. Optom Vis Sci 2000;77,12s:179.

Simpson T, Lau J, Jones L, Fonn D. Chemical properties predict the dimensions of ocular discomfort of ophthalmic drops. Invest Ophthalmol Vis Sci 2000;41: E-abstract 1440.

Louie D, Senchyna M, Jones LW, May C, Schubert N, Dumbleton K. Lysozyme deposition and removal from a high Dk silicone hydrogel contact lens material: a comparison of 7-day vs. 30-day wear. Invest Ophthalmol Vis Sci 2000;41,4:s71 #369.

Jones L, Dumbleton K, Simpson T, Fonn D. Direct vs off-line grading of bulbar and limbal hyperemia: a comparison of high Dk vs low Dk extended wear lenses. Contact Lens & Anterior Eye 2000;23,4:175.

Louie D, Senchyna M, Jones L, May C, Schubert N, Dumbleton K. Lysozyme deposition and removal from a high Dk silicone-hydrogel contact lens material: a comparison of 7 day vs 30 day wear. Contact Lens & Anterior Eye 2000;23,4:176.

Jones L. Mucin ball post lens debris in high Dk silicone hydrogel wearers. Contact Lens & Anterior Eye 2000;23,4:150-151.

Simpson T, Lau J, Jones L, Richter D, Dumbleton K, Fonn D. Physical chemistry predicts the dimensions of ocular discomfort of ophthalmic drops. Contact Lens & Anterior Eye 2000;23,4:172.

Jones L, Lau J. Physical properties of multi-purpose contact lens solutions. Contact Lens & Anterior Eye 2000;23,4:172.

Jones D, Jones L, Dumbleton K, Pritchard N. Recording of contact lens complications using digital image technology. Contact Lens & Anterior Eye 2000;23,4:160.

Jones L, Evans K, Mann A, Tighe B. The impact of contact lens polymer water content and charge on the deposition of tear-derived proteins and lipids. Institute for Polymer Research Symposium, University of Waterloo, 2000.

Jones L, Cheng A, Woods C, Levitt L. Frequency of follow-up in asymptomatic contact lens wearers: Reaching a consensus view. B&L ERS (Berlin, Germany), 2000.

Jones L, Lau J. Physical properties of multi-purpose contact lens solutions. B&L ERS (Berlin, Germany), 2000.

Jones L, Louie D, Senchyna M, Dumbleton K, Sorbara L. A comparative evaluation of lysozyme deposition on Etafilcon & silicone-hydrogel contact lens materials. B&L ERS (Berlin, Germany), 2000.

Louie D, Senchyna M, Jones L, May C, Schubert N, Dumbleton K. Lysozyme deposition and removal from a high Dk silicone-hydrogel contact lens material: A comparison of 7-day vs 30-day wear. B&L ERS (Berlin, Germany), 2000.

Simpson T, Lau J, Jones L, Fonn D. Chemical properties predict the dimensions of ocular discomfort of ophthalmic drops. BCLA Conference (Birmingham, UK), 2000.

1999

Dumbleton K, Jones L, Williams-Lyn D, Fonn D, Chalmers R. Mucin ball post lens debris in high Dk silicone hydrogel wearers. Optom Vis Sci 1999;76,12s:226.

Jones L. The impact of material composition and replacement frequency on contact lens deposition. Peter-Abel Contact Lens Award Presentation, VDC Congress (Fulda, Germany), 1999.

Jones L, Dumbleton K, Simpson T, Fonn D. Direct vs off-line grading of bulbar and limbal hyperemia: a comparison of high Dk vs low Dk extended wear lenses. Optom Vis Sci 1999;76,12s:14.

Hutchings N, Jones L. Evaluation of the measurement of ocular rotation by a computerised Hess screen. Optom Vis Sci 1999;76,12s:131.

Dumbleton K, Jones L, Williams-Lyn D, Fonn D, Chalmers R. Mucin ball post-lens debris in high-Dk silicone hydrogel wearers. Optom Vis Sci 1999;76,12s:226.

Lau J, Jones L. Physical properties of multi-purpose contact lens solutions. Optom Vis Sci 1999;76,12s:161.

Simpson T, Lau J, Jones L, Richter D, Dumbleton K, Fonn D. Physical properties predict the dimensions of ocular discomfort of ophthalmic drops. Optom Vis Sci 1999;76,12s:237.

Sehizadeh M, Simpson T, Jones L. The accuracy and repeatability of two autorefractor-keratometers (Nikon NRK-8000 and Canon RK-1) using a dioptric power matrix method. Optom Vis Sci 1999;76,12s:185.

Jones L, Jones D, Simpson T. The impact of replacement frequency and care regimen on subjective satisfaction with disposable/frequent replacement lenses. Optom Vis Sci 1999;76,12s:172.

Jones D, Jones L, Simpson T. The subjective satisfaction of presbyopes wearing disposable/frequent replacement lenses: a comparison of monovision versus reading over-spectacles. Optom Vis Sci 1999;76,12s:174.

Jones L, Evans K, Mann A, Tighe B. Inter- and intra-subject variability in the subjective performance and deposition of single-use daily disposable contact lenses. Invest Ophthalmol Vis Sci 1999;40,4:s907.

Jones L, Evans K, Mann A, Tighe B. Inter- and intra-subject variability in the deposition of group II and group IV single-use daily disposable lenses. Contact Lens & Anterior Eye 1999;22,4:162.

Jones L, Jones D, Franklin V, Tonge S, Tighe B. Multi-purpose solution effects on the clinical performance and spoilation of daily wear monthly planned-replacement contact lenses. Contact Lens & Anterior Eye 1999;22,4:155.

Jones L, Jones D, Simpson T. The influence of replacement frequency and care regimens on subjective satisfaction with disposable/frequent replacement lenses. Contact Lens & Anterior Eye 1999;22,4:147.

Jones D, Jones L, Simpson T. The subjective satisfaction of presbyopes wearing disposable/frequent replacement lenses: a comparison of monovision versus reading over-spectacles. Contact Lens & Anterior Eye 1999;22,4:162.

Jones L, Evans K, Mann A, Tighe B. Inter and intra-subject variability in the subjective performance and deposition of single-use daily disposable contact lenses. BCLA Conference (Birmingham, UK), 1999.

1998

Jones L, Evans K, Mann A, Tighe B. Inter- and intra-subject variability in the deposition of group II and group IV single-use daily disposable contact lenses. Optom Vis Sci 1998;75,12s:164.

Jones L, Franklin V, Evans K, Mann A, Tighe BJ. The influence of NVP on the deposition performance of Group IV hydrogel materials. Optom Vis Sci 1998;75,12s:163.

Mann A, Jones L, Tighe B. The impact of daily disposability on the deposition of immuno-regulatory proteins. Tenth Symposium on the Material Science and Chemistry of Contact Lenses, New Orleans, 1998.

Jones L, Norris A. Continuous wear vs single-use daily disposables: Practitioner and patient perspectives in the UK. Optom Vis Sci 1998;75,12s:186.

Jones D, Jones L, Franklin V, Tonge S, Tighe B. Multi-purpose solution effects on the clinical performance and spoilation of daily-wear monthly planned replacement contact lenses. Optom Vis Sci 1998;75,12s:276.

Jones L, Tonge S, Goodall S, Tighe B. The influence of tear and non-tear derived surface active components on the wettability of group IV hydrogel lenses. Optom Vis Sci 1998;75,12s:274.

Jones L. Contact lens materials - same or different?. Contact Lens & Anterior Eye 1998;21,4:125.

Jones L. Continuous wear vs single-use daily disposables: Practitioner & patient perspectives. Contact Lens & Anterior Eye 1998;21,4:128.

Tonge S, Goodall S, Rai H, Jones L, Tighe B. Validation of an in vitro model for studying the persistence of surfactants on the surface of group II and IV hydrogel contact lenses. Contact Lens & Anterior Eye 1998;21,4:138.

Jones L . The influence of tear and non-tear derived surface active components on the wettability of group IV hydrogel lenses. B&L European Conference (Prague), 1998.

Jones D, Jones L, Franklin V, Tonge S, Tighe B. Multi-purpose solution effects on the clinical performance and spoilation of daily-wear monthly planned replacement contact lenses. B&L ERS Symposium (Prague), 1998.

Jones D, Jones L, Franklin V, Tonge S, Tighe B. Multi-purpose solution effects on the clinical performance and spoilation of daily-wear monthly planned replacement contact lenses. Tenth Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans), 1998.

Jones L, Tonge S, Goodall S, Tighe B. The influence of tear and non-tear derived surface active components on the wettability of group IV hydrogel lenses. Tenth Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans), 1998.

Jones L, Norris A. Continuous wear vs single-use daily disposables: Practitioner and patient perspectives in the UK. B&L ERS (Prague), 1998.

Jones L, Norris A. Continuous wear vs single-use daily disposables: Practitioner and patient perspectives in the UK. Tenth Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans), 1998.

Jones L, Franklin V, Evans K, Mann A, Tighe BJ. The influence of NVP on the deposition performance of Group IV hydrogel materials. B&L ERS (Prague), 1998.

Jones L, Franklin V, Evans K, Mann A, Tighe BJ. The influence of NVP on the deposition performance of Group IV hydrogel materials. Tenth Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans), 1998.

1997

Tonge S, Goodall S, Jones L, Tighe B. The influence of non-tear derived surface-active components on the wettability of hydrogel lenses. Contact Lens & Anterior Eye 1997;20173.

Jones L, Jones D, Langley C, Houlford M. The influence of solution regimes on the in vivo wettability of Group II and Group IV frequent replacement lenses. Contact Lens & Anterior Eye 1997;20171.

Jones L, Franklin V, Tighe BJ. The relationship between physical and mechanical properties and handling performance of commercially available contact lens materials. Contact Lens & Anterior Eye 1997;20,4:166.

Jones L, Mann A, Evans K, Franklin V, Tighe BJ. The influence of replacement period on the deposition of FDA group II and group IV hydrogel contact lenses. Invest Ophthalmol Vis Sci 1997;38,4:50.

Jones L. Contact lens deposition: Myths vs reality. New Zealand Contact Lens Society Conference (Auckland), 1997.

Jones L. Contact lens materials - clinical implications of choice. New Zealand Contact Lens Society Conference (Auckland), 1997.

Tonge S, Goodall S, Jones L, Tighe B. The persistence of surfactants used on multipurpose solutions on the surface of hydrogel contact lens materials. An in vitro vs in vivo comparison. Ninth Symposium on the Material Science and Chemistry of Contact Lenses (New Orleans), 1997.

1996

Jones L, Jones D, Houlford M. A clinical comparison of three polyhexanide-preserved multi-purpose contact lens solutions. Optom Vis Sci 1996;73,12s:95.

Jones L, Mann A, Evans K, Franklin V, Tighe BJ. The effect of wearing time on the deposition of group II and group IV disposable contact lenses. Optom Vis Sci 1996;73,12s:162.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. An in vivo comparison of the spoilation performance of NVP and PVA containing high water content hydrogel contact lenses. Optom Vis Sci 1996;73,12s:95.

Franklin V, Evans K, Jones L, Tighe BJ. White spots and lipid profile variations. J BCLA 1996;19,4:152.

Jones L, Evans K, Franklin V, Mann A, Tighe BJ. The effect of wearing time on the deposition of group II & group IV contact lenses. J BCLA 1996;19,4:145.

Jones L, Evans K, Franklin V, Mann A, Tighe BJ. The influence of replacement frequency on the deposition of group II & group IV disposable contact lenses. B&L ERS Symposium (Seville), 1996.

Jones L. The influence of care regimens on the deposition of FDA group II & group IV disposable contact lenses. B&L Research Symposium (Seville, Spain), 1996.

Jones L, Franklin V, Evans K, Mann A, Tighe BJ. The influence of NVP on the deposition performance of Group IV hydrogel materials. BCLA Conference (Bournemouth), 1996.

Jones L, Jones D, Houlford M. A clinical comparison of three polyhexanide-preserved multi-purpose contact lens solutions. BCLA Conference (Birmingham, UK), 1996.

Jones L, Jones D, Houlford M. A clinical comparison of three polyhexanide-preserved multi-purpose contact lens solutions. B&L ERS Symposium (Seville), 1996.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. An in vivo comparison of the spoilation performance of NVP and PVA containing high water content hydrogel contact lenses. BCLA Conference (Birmingham, UK), 1996.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. An in vivo comparison of the spoilation performance of NVP and PVA containing high water content hydrogel contact lenses. B&L ERS Symposium (Seville), 1996.

Jones L, Jones D, Langley C, Houlford M. Reactive or proactive contact lens fitting - does it make a difference?. B&L Symposium (Seville), 1996.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. The spoilation and clinical performance of monthly versus three monthly group II disposable contact lenses. B&L Symposium (Seville), 1996.

1995

Franklin V, Sariri R, Evans K, Jones L, Ma J, Mann A, Singh-Gill U, Tighe BJ. The interaction of care solutions with tear components deposited on soft contact lenses. Optom Vis Sci 1995;72,12s:152.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. The spoilation and clinical performance of monthly versus three monthly group II disposable contact lenses. Optom Vis Sci 1995;72,12s:147.

Jones L, Jones D, Langley C, Houlford M. Reactive or proactive contact lens fitting - does it make a difference?. Optom Vis Sci 1995;72,12s:146.

Franklin V, Evans K, Jones L, Singh-Gill U, Tighe BJ. Interaction of tear lipids with soft contact lenses. Optom Vis Sci 1995;72,12s:145.

Franklin V, Evans K, Jones L, Sariri, Singh-Gill U, Tighe BJ. Further studies on the interaction of the biochemical species of the ocular environment and soft contact lenses. Optom Vis Sci 1995;72,12s:145.

Tonge SR, Ma J, Jones L, Tighe BJ. Studies of in vivo versus in vitro wettability of soft contact lenses. J BCLA 1995;18,4:139.

Jones D, Jones L. Problems, problems, problems. J BCLA 1995;18,4:139.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. A multi-solution comparison of group II v group IV disposable contact lenses. J BCLA 1995;18,4:136.

Jones L. A multi-solution comparison of group II vs group IV disposable contact lenses. 7th Symposium on Material Science & Chemistry of Contact Lenses (New Orleans), 1995.

Franklin V, Evans K, Jones L, Singh-Gill U, Tighe BJ. 299.Interaction of tear lipids with soft contact lenses. BCLA Conference (London), 1995.

Franklin V, Sariri R, Evans K, Jones L, Ma J, Mann A, Singh-Gill U, Tighe BJ. The interaction of care solutions with tear components deposited on soft contact lenses. BCLA Conference (London), 1995.

Franklin V, Evans K, Jones L, Sariri R, Singh-Gill U, Tighe BJ. Further studies on the interaction of the biochemical species of the ocular environment and soft contact lenses. BCLA Conference (London), 1995.

Jones L, Jones D, Langley C, Houlford M. Reactive or proactive contact lens fitting - does it make a difference?. BCLA Conference (London), 1995.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. The spoilation and clinical performance of monthly versus three monthly group II disposable contact lenses. 7th Symposium on Material Science & Chemistry of Contact Lenses (New Orleans), 1995.

Jones L, Franklin V, Evans K, Sariri R, Tighe BJ. The spoilation and clinical performance of monthly versus three monthly group II disposable contact lenses. BCLA Conference (London), 1995.

Tighe BJ, Fitton JH, Jones L, Guillon M. Vitronectin as an inflammatory marker in contact lens wear monitored by a novel on-lens assay. 7th Symposium on Material Science & Chemistry of Contact Lenses (New Orleans), 1995.

1994

Grant R, Jones L, Grant T. A new high water content hydrogel lens vs a low water content benchmark: a comparative study. Optom Vis Sci 1994;71,12s:54.

Jones L, Jones D, Langley C. A comparative evaluation of two high Dk aspheric RGP contact lenses. J BCLA 1994;17,4:154.

Jones D, Jones L. Every picture tells a story. J BCLA 1994;17,4:154.

Franklin V, Jones L, Ma J, Sariri R, Singh-Gill U, Evans K, Tighe BJ. Studies on the interaction of ocular deposition on spoilation resistant materials. J BCLA 1994;17,4:153.

Franklin V, Goodwin C, Jones L, Ma J, Sariri R, Singh-Gill U, Evans K, Goodwin C, Tighe BJ. The effect of currently available disinfection regimes on ocular spoilation processes. J BCLA 1994;17,4:153.

Jones L, Ma J, Franklin V, Tighe BJ. In vivo versus in vitro wettability of hydrogel materials. J BCLA 1994;17,4:154.

Jones L, Franklin V, Tighe BJ. The spoilation and clinical performance of a new biomimetic contact lens material. J BCLA 1994;17,4:145.

Tighe BJ, Fitton JH, Jones L, Guillon M. Vitronectin as an inflammatory marker in contact lens wear monitored by a novel on-lens assay. Optom Vis Sci 1994;70,12s:67.

Jones L, Davies I, Jones D. The time dependent effect of hydrogen peroxide neutralisation on the fitting characteristics of group IV disposable lenses. B&L ERS (Lisbon), 1994.

Jones L, Jones D, Langley C. A comparative evaluation of two high Dk aspheric RGP contact lenses. B&L ERS (Lisbon), 1994.

Franklin V, Jones L, Tighe BJ. It's a dirty business.... BCLA Conference (Torquay), 1994.

Tighe BJ, Fitton JH, Jones L, Guillon M. Vitronectin as an inflammatory marker in contact lens wear monitored by a novel on-lens assay. BCLA Conference (Torquay), 1994.

1993

Jones L, Davies I, Jones D. Effect of hydrogen peroxide neutralisation times on the fitting characteristics of group IV disposable contact lenses. Opthal Physiol Opt 1993;14,1:108.

Jones L. Effect of hydrogen peroxide neutralisation times on the fitting characteristics of group iv disposable Page 47 lenses. Society for Experimental Optometry Meeting (Birmingham, England), 1993.

Jones L. The comparative surface spoilation and clinical performance of two daily-wear disposable lens systems. BCLA Annual Clinical Conference (London), 1993.

Jones L. Daily disposable lenses. 25th Anniversary Conference Barraquer Clinic (Bogota, Columbia), 1993.

Jones L. The effect of neutralisation times on parameter stability of group IV disposable lenses. 25th Anniversary Conference Barraquer Clinic (Bogota, Columbia), 1993.

1992

Jones L, Horne A, Franklin V, Tighe BJ. The comparative surface spoilation and clinical performance of two daily-wear disposable lens systems. Optom Vis Sci 1992;69,12s:23.

1991

Jones L, Franklin V, Horne A, Tighe BJ. Deposition trends of daily-wear Acuvue disposable lenses - preliminary findings. Optom Vis Sci 1991;68,12s:72.

Jones L. Deposition and ionic Lenses. B&L ERS (Geneva, Switzerland), 1991.

Jones L. Ionic lenses - What are they?. Scottish Contact Lens Society Conference (Turnberry), 1991.

Jones L. Whose profile is it?. Scottish Contact Lens Society Conference (Turnberry), 1991.

Jones L. Deposition trends of daily-wear Acuvue disposable lenses. CLAO Meeting (Las Vegas, Nevada), 1991.

Franklin V, Horne A, Jones L, Tighe BJ. Early deposition trends of group 1 (polymacon & tetrafilcon A) and group 3 (bufilcon A) materials and the efficacy of surfactant cleaning. CLAO Meeting (Las Vegas, Nevada), 1991.

Jones L, Tonge S, Goodall S, Tighe BJ. The influence of tear and non-tear derived surface active components on the wettability of hydrogel lenses. Contact Lens & Anterior Eye ;20,4:163-1997.

Walther H, Lorentz H, Heynen M, Kay L, Jones L. The effect of concentration the in vitro radiochemical uptake of three lipids on silicone hydrogel and conventional hydrogel contact lens materials. Contact Lens & Anterior Eye ;34,s21:.

Professional Publications

2016

Guthrie S, Dumbleton K, Jones L. Is There a Relationship Between Care System and Compliance?. Contact Lens Spectrum 2016;31,April:40-43.

Subbaraman L, Pruitt J, Jones L. Measuring Contact Lens Friction. Contact Lens Spectrum 2016;31,January:40-43.

Jones L, Ng A, Thompson B. Keeping up with ocular fatigue in the digital era. Contact Lens Spectrum 2016;31(6):Supplement.

Jones L. Avoiding contact lens discomfort and dropout. EyeCare Update 2016;1(2):2-3.

Morgan P, Woods C, Tranoudis I, Helland M, Efron N, Jones L, Teufl M, Grupcheva C, Lemos R, Jones D, Beeler-Kaupke M, Qi P, Tan K-O, Belikova J, Pult H, Ravn O, Santodomingo-Rubido J, Malet F, Plakitsi A, Vegh M, Erdinest N, Jafari A, Montani G, Itoi M, Sun B, Bendoriene J, van der Worp E, Pintor R, Monroy J, Chia J, Awasthi S, Lam W, Romualdex-Oo J, Abesamis-Dichoso C, Gonzalez-Meijome J, Gierow P, Stabuc Silih M, Hsiao J, Nichols J. International contact lens prescribing in 2015. Contact Lens Spectrum 2016;31(1):24-29.

2014

Ng AY, Bitton E, Jones L. How to diagnose and manage blepharitis caused by Demodex overpopulation. Contact Lens Spectrum 2014;29,December:36-38,40,41.

Guthrie S, Dumbleton K, Jones L. Financial Implications of Patient Compliance. Contact Lens Spectrum 2014;29,December:42-45.

Morgan P, Bright F, Cavet M, Dobson C, Efron N, Jones L, Papas E. A closer look at fluorescein. Global Contact Lens Care symposium supplement.. Supplement to Optician 2014;March; 247,(6440):.

2013

Morgan P, Bright F, Cavet M, Dobson C, Efron N, Jones L, Papas E. A closer look at fluorescein. Contact 2013;Dec1-16.

Jones L. Hydrogel contact lens materials: Dead and buried or about to rise again?. ContactLensUpdate.com 2013.

Jones L. Measuring friction and lubricity of soft contact lenses: A review.. Contact Lens Spectrum 2013;28(13).

Woods J, Woods C, Fonn D, Jones L. Potential acceptance of a daily disposable silicone hydrogel multifocal lens in emmetropic presbyopes. Optom Vis Sci 2013;88: E-Abstract 135100.

2012

Nguyen D, Hui A, Weeks A, Heynen M, Martell E, Sheardown H, Jones L. Release of Ciprofloxacin-HCl and Dexamethasone phosphate by soft contact lens materials loaded with Hyaluronic Acid. Materials 2012;5684-698.

Djalal Y, Bitton E, Jones L. Tearing the tears apart. Contact Lens Spectrum 2012;27,5:46-50.

2011

Jones L. The University of Waterloo’s Centre for Contact Lens Research. The Ocular Surface 2011;9,4:242-244.

Srinivasan S, Menzies K, Sorbara L, Jones L. Meibography of the upper lid. Optician 2011;242,6318:12-15.

Srinivasan S, Sorbara L, Jones L, Sickenberger W. Imaging the structure of the meibomian glands . Contact Lens Spectrum 2011;26,7:52-53.

Jones L, Papas E. The next 25 years: The future of contact lenses. Contact Lens Spectrum 2011;26,6:14-15.

Bitton E, Jones L. Don’t flip over lens inversion markers. Contact Lens Spectrum 2011;26,2:51-52.

2010

Hall B, Jones L. Countering noncompliance with lens care and case technology. Contact Lens Spectrum 2010;25,12:50-51.

Jones L, Menzies K, Subbaraman L. Comfortable contact lenses: A case of Mission Impossible?. Contact Lens Spectrum 2010;25,7:45-48.

Srinivasan S, Jones L. Tear osmolarity measurements using novel osmometers. Optician 2010;240,6270:50-52.

Jones L, Epstein A, Holden B, Szczotka-Flynn L. The current realities of silicone hydrogel lenses. Contact Lens Spectrum 2010,Oct:1-15.

Hui A, Jones L. Contact lenses offer effective drug delivery. Optometry Pharma 2010,Sept:26-27.

Jones L. New options for enhancing contact lens wetting. Refractive Eyecare 2010,August:9-11.

Dumbleton K, Woods C, Jones L, Fonn D. How compliant are today’s lens wearers?. Contact Lens Spectrum 2010;25,6:34-37.

Richter D, Dumbleton K, Guthrie S, Woods C, Jones L, Fonn D. Patient and practitioner compliance with silicone hydrogel and daily disposable lens replacement in Canada. Canadian Journal of Optometry 2010;72,1:10-19.

Dumbleton K, Jones L. Why wouldn’t you fit your astigmatic patients with toric silicone hydrogel lenses?. Silicone Hydrogels Website 2010,March :.

2009

Dalton K, Subbaraman L, Rogers R, Jones L. Physikalische eigenschaften von pflegelosungen fur weiche kontaklinsen. Die Kontaklinse 2009;415-20.

Dumbleton K, Jones L. Silicone hydrogels – no longer for just a select few. Contact Lens Spectrum 2009;24,4:20.

Dumbleton K, Jones L. The evolution of contact lens wetting agents. Contact Lens Spectrum 2009;24,10:20.

Dumbleton K, Jones L. What contact lens materials are patients wearing?. Contact Lens Spectrum 2009;24,8:21.

Dumbleton K, Jones L. Don’t compromise with your teenagers. Contact Lens Spectrum 2009;24,2:24.

Epstein A, Andrasko G, Jones L, Kading D, Lebow K, Schachet J, Townsend W. New perspectives on patient satisfaction: The science of comfort, part 3. Ensuring wettability and comfort. Contact Lens Spectrum 2009,July:3-6.

Epstein A, Andrasko G, Jones L, Kading D, Lebow K, Schachet J, Townsend W. New perspectives on patient satisfaction: The science of comfort, part 2. Keeping lenses clean. Contact Lens Spectrum 2009,April:3-7.

Epstein A, Andrasko G, Jones L, Kading D, Lebow K, Schachet J, Townsend W. New perspectives on patient satisfaction: The science of comfort, part 1. Biocompatible disinfection. Contact Lens Spectrum 2009,January:3-10.

French K, Jones L. Zehn jahre silikon-hydrogellinsen. Die Kontaklinse 2009;320-27.

Jones L. Silicone hydrogel deposition. Contact Lens Spectrum 2009;24,11:14-15.

Jones L. Solution-induced corneal staining does matter. Contact Lens Spectrum 2009;24,2:18.

Jones L. Essential fatty acids and dry eye: What do we know?. Contact Lens Spectrum 2009;24,7:14-15.

Jones L, Dumbleton K. Contact lens deposits - patient or material driven?. Contact Lens Spectrum 2009;24,6:19.

Jones L. Drug delivering contact lenses: A dream worth chasing?. Contact Lens Spectrum 2009;24,3:18-19.

Luensmann D, Jones L. Albuminablagerungen auf kontaklinsen-materialien: Ein uberblick. Die Kontaklinse 2009;518-23.

Sulley A, Jones L, French K. Silicone hydrogels - ten years on. Dispensing Optics 2009;24,8:4-12.

Subbaraman L, Jones L. What influences contact lens related dry eye?. Contact Lens Spectrum 2009;24,7:39-43.

Dumbleton K, Jones L. The quest for all-day comfort. Contact Lens Spectrum 2009;24,12:17.

2008

French K, Jones L. A decade with silicone hydrogels: part 1. Optometry Today 2008;48,16:42-46.

French K, Jones L. A decade with silicone hydrogels: part 2. Optometry Today 2008;48,18:38-43.

Jones L, Christie C. Soft contact lens solutions review part 2: Modern generation care systems. Optometry in Practice (UK) 2008;943-62.

Jones L, Lorentz H. The new comfilcon A material. Review of Optometry 2008,April:2-5.

Jones L, Woods C. An eye on the world's first silicone hydrogel daily disposable contact lens. The Optician 2008;236,6172:33-34.

Jones L. The past present and future of soft contact lenses. Eye-Zone 2008,21:41-42.

Jones L, Woods C. Compromises’ end? The introduction of a silicone hydrogel daily disposable lens . Silicone Hydrogels Website 2008.

2007

Jones L, Dumbleton K. Comfilcon A: a new silicone hydrogel material. Contact Lens Spectrum 2007;22,8:23.

Jones L, Dumbleton K. A silicone hydrogel material gets an upgrade. Contact Lens Spectrum 2007;22,12:18.

Jones L. Understanding the link between wettability and lens comfort: Improving ocular health and comfort with silicone hydrogel contact lenses. Contact Lens Spectrum 2007;22s4-s6.

Jones L, Dumbleton K, Woods J. A made-to-ofer silicone hydrogel lens. Optician 2007;233,6104:45-47.

Jones L, Senchyna M. Soft contact lens solutions review part 1: Components of modern care regimens. Optometry in Practice 2007;845-56.

Jones L, Dumbleton K, Woods J. Fitting a challenging case with a custom silicone hydrogel. Contact Lens Spectrum 2007;22,6:17.

Jones L, Dumbleton K, Woods J. Fitting and evaluating a custom silicone hydrogel lens. Contact Lens Spectrum 2007;22,4:19.

Jones L, Dumbleton K, Woods J. Introducing a made-to-order silicone hydrogel lens. Contact Lens Spectrum 2007;22,2:23.

Jones L, Dumbleton K, Woods J. A made to order silicone hydrogel lens. Optician 2007;233,6104:45-47.

2006

Ghormley R, Jones L. Managing lipid deposition on silicone hydrogel lenses. Contact Lens Spectrum 2006;21,1:21.

Fonn D, Kerby K, Simpson T, Bitton E, Rajani N, Jones L, Berthiaume L, Miranda T, Caffrey B, Lutzi D, Maroun F, Leinweber G. Round table discussion on dry eye. Can J Optom 2006;68,5:189-200.

Jones L, Subbaraman L, Rogers R, Dumbleton K. Surface treatment, wetting and modulus of silicone hydrogels. Optician 2006;232,6067:28-34.

Jones L. Hidrogeles de silicona y eleccion de la pauta de mantenimiento. Journal of the Spanish College of Optometrists 2006;40666-68.

2005

Jones L, Dumbleton K. Silicone hydrogels, part one: Technological developments. Optometry Today 2005;2823-29.

2004

Cullen A, Jones L. Diseases of the ocular adnexa and anterior segment: Diseases of the cornea. Institute of Optometry web-based course 2004,Sept:.

Cullen A, Jones L. Diseases of the ocular adnexa and anterior segment: Diseases of the lacrimal system. Institute of Optometry web-based course 2004,Sept:.

Cullen A, Jones L. Diseases of the ocular adnexa and anterior segment: Diseases of the conjunctiva. Institute of Optometry web-based course 2004,Aug:.

Cullen A, Jones L. Diseases of the ocular adnexa and anterior segment: Diseases of the lids and lashes. Institute of Optometry web-based course 2004,Aug:.

Jones L, Tighe B. Silicone hydrogel contact lens materials update – Part 2. Silicone Hydrogel Web-Site 2004,July:.

Jones L, Dumbleton K. Silicone hydrogels: Will they displace conventional lenses?. Optometry Today 2004,Aug:34-41.

Jones L. Understanding incompatibilities. Contact Lens Spectrum 2004,July:4-7.

Jones L, Tighe B. Silicone hydrogel contact lens materials update – Part 1. Silicone Hydrogel Web-Site 2004,July:.

2003

Jones L. Contact lens materials update: part one. Optician 2003;225,5891:24-31.

Jones L. Contact lens materials update: part two. Optician 2003;225,5895:30-32.

2002

Jones L. How to equip your contact lens practice . Optician 2002;223,5854:24-27.

Dumbleton K, Jones L. Introducing silicone-hydrogel contact lenses: part 1 - Material properties and patient selection. Optician 2002;223,5836:16-22.

Jones L, Dumbleton K. Introducing silicone-hydrogel contact lenses: part 2 - fitting procedures and in-practice protocols. Optician 2002;223,5840:37-45.

Dumbleton K, Jones L. Introducing silicone-hydrogel contact lenses: part 3 - Follow-up and management. Optician 2002;223,5845:34-43.

Jones L. Modern contact lens materials: A clinical performance update. Contact Lens Spectrum 2002;17,9:24-35.

Jones L, Dumbleton K. Practitioner attitudes to continuous wear and daily disposable CLs . Optician 2002;223,5485:30-32.

Jones L, Senchyna M. Protein and lipid deposition of silicone-hydrogel contact lens materials. Silicone Hydrogel Web-Site 2002,Oct:.

Fonn D, Dumbleton K, Jones L, du Toit R, Sweeney D. Silicone hydrogel material and surface properties. Contact Lens Spectrum 2002;17,3:24-28.

Jones L, Dumbleton K. Silicone-hydrogel contact lenses. part 1: Evolution and current status. Optometry Today (UK) 2002;42,18:26-32.

van der Worp E, Morgan P, Efron N, Helland M, Jones L, Tranoudis Y, Woods CA. A survey of contact lens fitting: an international perspective (Enquete contactlensaanpassingen International 2001). Visus 2002;115-19.

2001

Jones L, Christie C. Contact lens care: part 9 - rigid lens care systems: an overview. Optician 2001;222,5830:22-27.

Morgan P, Efron N, Helland M, Jones L, Woods CA, van der Worp E. How does the UK market compare with other countries? . Optician 2001;222,5799:26-32.

Jones L. Management and diagnosis of the red eye in clinical practice . 2001. [ Show Abstract ]

Distance continuing education article for Vision Express (UK Optical Chain)

Jones L, Christie C. Rigid lens care systems: An overview. Optician 2001;222,5830:22-27.

van der Worp E, Morgan P, Efron N, Helland M, Jones L, Woods CA. Contactlens aanpassingen International. Visus 2001;1151-157.

2000

Jones L. Acquired strabismus. Optician 2000;220,5778:16-25.

Jones L, Cullen A. Diagnosis and management of common corneal complications - part 1. Optician 2000;220,5767:22-28.

Jones L, Cullen A. Diagnosis and management of common corneal complications - part 2. Opticia 2000;220,5772:26-31.

Cullen A, Jones L. Flare, cells & KP. Optician 2000;219,5756:28-31.

Jones L. Ocular therapeutics: is it really worth the effort?. Optician 2000;219,5745:40-42.

Cullen A, Jones L. Secrets of the sclera. Optician 2000;219,5756:26-28.

1999

Jones L, Cullen A. Anterior segment eye disease: part 1 - disorders of the lids and ocular adnexa. Optician 1999;217,5693:23-32.

Jones L, Eperjesi F, Evans B. Binocular vision evaluation in practice . Optometry Today (UK) 1999;39,4:33-36.

Jones L. Persistent corneal infiltrates. Practical Optometry 1999;10,2:83-85.

Jones L. "TRUE" extended wear hydrogel lenses: practical considerations . Contactologia 1999;21104.

Cullen A, Jones L. Disorders of the conjunctiva. Optician 1999;217,5698:19-26.

1998

McMillan R, Stevenson L, Ferguson L, Jones L. CL record cards: their use with clinical grading scales. Optician 1998;216,5667:36-38.

1997

Hickson-Curran S, Nason R, Dubow B, Jones L, Lofstrom T, Pace P. Enhanced Acuvue under trial. Optician 1997;214,5626:36-42.

1995

Jones L, Jones D, Langley C, Houlford M. The subjective response of 100 consecutive patients to 1-day disposable lenses. Optician 1995;211,5536:28-32.

Jones L, Jones D, Langley C. The comparative performance of two aspheric rigid gas permeable lens designs. Optician 1995;210,5526:28-36.

Jones L, Jones D. Three and nine O'clock corneal staining. Optician 1995;210,5526:20-22.

Jones L, Jones D. Blepharitis. Optician 1995;210,5522:32-33.

Jones L, Jones D. RGP lens binding (adherence). Optician 1995;210,5517:28-29.

Jones L, Jones D. SMILE staining and dehydration. Optician 1995;210,5513:24-25.

Jones L, Jones D. Dimple-veil staining. Optician 1995;210,5509:32.

Jones L, Jones D. Superior epithelial arcuate lesions. Optician 1995;209,5500:32-33.

Jones L, Jones D. Corneal staining assessment. Optician 1995;209,5496:30-32.

Jones L, Jones D. Meibomian gland dysfunction. Optician 1995;209,5491:30-31.

1992

Jones L, Woods C. Contact lens fitting and design. Optician 1992;203,5354:16-22.

Broughton R, Jones L. Clinical investigation of the young. DOCET module for a distance learning package in "Children's Visual Problems" for the British College of Optometrists 1992.

1991

Jones L, Jones D. Persecon 92E: design and clinical performance. Optician 1991;203,5333:16-23.

1988

Jones L. High water content lenses used daily. J Brit Contact Lens Assoc 1988;Scientific Meetings26-31.

Jones L. Silicone hydrogels and care regimen choice. Contacto ;214-7.

Jones L. A new silicone hydrogel lens comes to market. Contact Lens Spectrum ;22,10:23.

Books

2017

Jones L, Sorbara L, Stahl U, Thom M, Guthrie S. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 43. 2017.

2016

Jones L, Sorbara L, Stahl U, Thom M, Guthrie S. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 42. 2016.

Liu S, Jones L, Gu F. Nanotechnology and Nanomaterials in Ophthalmic Drug Delivery. In: Nano-Biomaterials for Ophthalmic Drug Delivery, ed. Pathak Y, Sutariya V, Hirani A. Springer International Publishing. 2016.

2015

Jones L, Sorbara L, Stahl U, Thom M, Guthrie S. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 41. 2015.

2014

Jones L, Sorbara L, Stahl U, Thom M, Guthrie S. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 40. 2014.

2013

Verma M, Liu S, Jones L, Gu F. Dextran-based nanoparticles for sustained drug delivery: applications in dry eye treatment and cancer therapy. In: Dextran: Chemical Structure, Applications and Potential Side Effects, ed. GP Figgs. 2013.

Srinivasan S, Jones L. Contemporary dry eye tests. In: Dry Eye Syndrome: Basic and Clinical Perspectives.. Future Medicine Ltd. 2013.

Jones L, Sorbara L, Stahl U, Guthrie S, Menzies K, Rossy J, Thom M. Contact Lens Compendium: Contact Lenses and Solutions Available in Canada. Vol 39. 2013.

2010

Jones L, Srinivasan S. Clinical Instruments. In: Contact Lens Practice 2nd Edition. Butterworth-Heinemann. 2010.

2009

Jones L, Dumbleton K. Contact Lenses. In: Optometry: Science, Techniques and Clinical Management. Elsevier. 2009.

2008

Jones L, Dumbleton K. Extended and Continuous Wear. In: Clinical Manual of Contact Lenses. Lippincott Williams and Wilkens. 2008.

2007

Jones L, Jones D. Common Contact Lens Complications: Recognition and Management. Elsevier. 2007.

2006

Jones L, Dumbleton K. Soft contact lens fitting. In: Contact Lenses 5th Edition, ed. Speedwell L, Phillips A. Butterworth-Heinemann. 2006.

Jones L, Dumbleton K. Soft Extended Wear and Complications. In: Manual of Contact Lens Prescribing and Fitting, ed. Hom M, Bruce A. Butterworth-Heinemann. 2006.

2005

Jones L, Dumbleton K. Soft Contact Lens Extended Wear and Continuous Wear. In: Manual of Contact Lens Prescribing and Fitting, ed. Milton H. Hom. Butterworth Heinemann. 2005.

2002

Jones L. Clinical Instruments. In: Contact Lens Practice, ed. Nathan Efron. Butterworth-Heinemann. 2002.

2001

Jones L, Jones D. Slit Lamp Biomicroscopy. In: The Cornea, ed. Nathan Efron. Butterworth-Heinemann. 2001.

2000

Jones L, Jones D. Common Contact Lens Complications: Recognition and Management. Butterworth-Heinemann. 2000.

1990

Morris J, Jones L. Soft lens fitting techniques and design. In: Contact Lens Yearbook. 1990.