Publications

Showing 25 results out of 535 in total.

Wolffsohn,J. S., Morgan,P. B., Barnett,M., Downie,L. E., Jacobs,D. S. Jones,L. W., Richdale, K., Stapleton,F., Vincent,S. J., Willcox,M. Contact Lens Evidence-Based Academic Reports (CLEAR) Contact Lens Anterior Eye 2021;44(2):129-131 [ Show Abstract ]

Since contact lenses were invented in 1887, innovations have included advances in optical design, material, care systems, wear modality, lens size, lens shape and applications. Over 19,000 peer reviewed academic papers on the contact lenses have been published. The Contact Lens Evidence-based Academic Reports (CLEAR) follow the exemplary work of organisations such as the Tear Film and Ocular Surface Society dry eye, meibomian gland disease, contact lens discomfort and dry eye II workshops and the International Myopia Institute white papers on myopia control, in collating and appraising the academic literature in an ocular field of interest. CLEAR represent the work of nearly 100 multidisciplinary experts in the field, who set out to critically review, synthesise and summarise the research evidence on contact lenses to date; this serves to inform both clinical practice, manufacturing innovation and future research directions.

Wolffsohn,J. S., Travé-Huarte,S., Jones,L., Craig,J. P., Wang,M. T. M., the TFOS ambassadors. Clinical practice patterns in the management of dry eye disease: A TFOS international survey Ocular Surface 2021;21(July):78-86 [ Show Abstract ]

Purpose
To examine clinical management and prescribing patterns for dry eye disease (DED), in relation to severity and subtype, by eye care practitioners across the globe.

Methods
An online, anonymous cross-sectional survey (on Qualtrics) translated into 14 languages was distributed to eye care practitioners across the globe. The survey included six questions around the management of DED, in relation to severity and subtype.

Result
The survey was completed by 1139 eyecare professionals (37% ophthalmologists and 58% optometrists) from 51 countries. Management varied significantly by continent and country (p < 0.01). The most commonly recommended management approaches, internationally, included general advice (87%), low (85%) and high (80%) viscosity-enhancing unpreserved lubricants and lid wipes/scrubs (81%). Some treatments were prescribed largely independently of severity (e.g. artificial tears and nutritional supplements) while oral antibiotics, punctal occlusion, topical anti-inflammatory/immunosuppressants, secretagogues, biologics, therapeutic contact lenses and surgical approaches were prescribed by more practitioners as severity increased. Essential fatty acids, lipid sprays/drops, lid hygiene, warm compresses, intense pulsed light therapy and antibiotics (topical or oral) were more commonly recommended for evaporative DED, while punctal occlusion, therapeutic contact lenses, secretagogues and biologics were more commonly recommended for aqueous deficient DED.

Conclusions
DED management differs across continents and countries. A wide range of management strategies are utilised at each severity level and between subtypes. The survey results enable clinicians to benchmark their practice to that of their peers, indicate where further research is required to optimise patient management and inform industry on how best to target product development.

Wong,K. Y., Phan,C.M., Chan,Y.T., Chuy-Ying Yuen,A., Zhao,D., Chan,K. Y., Do,C. W., Chuen Lam,T., Han Qiao,J., Wulff,D., Hui,A., Jones,L., Wong,M. S. A review of using Traditional Chinese Medicine in the management of glaucoma and cataract Clinical and Experimental Optometry 2023;Online ahead of print [ Show Abstract ]

Traditional Chinese Medicine has a long history in ophthalmology in China. Over 250 kinds of Traditional Chinese Medicine have been recorded in ancient books for the management of eye diseases, which may provide an alternative or supplement to current ocular therapies. However, the core holistic philosophy of Traditional Chinese Medicine that makes it attractive can also hinder its understanding from a scientific perspective – in particular, determining true cause and effect. This review focused on how Traditional Chinese Medicine could be applied to two prevalent ocular diseases, glaucoma, and cataract. The literature on preclinical and clinical studies in both English and Chinese on the use of Traditional Chinese Medicine to treat these two diseases was reviewed. The pharmacological effects, safety profile, and drug-herb interaction of selected herbal formulas were also investigated. Finally, key considerations for conducting future Traditional Chinese Medicine studies are discussed.

Wong,S., Murphy,P.J., Jones,L. Tear evaporation rates: What does the literature tell us? Contact Lens and Anterior Eye 2018;41(3):297-306 [ Show Abstract ]

Purpose: A previous literature review reported tear evaporation rates (TERs) from studies conducted on rabbits and humans between 1941 and 2003. Closer examination of the presented data revealed inaccuracies in the reporting of some values. This paper presents updated tables of TERs using values from the original papers cited in the review, in addition to incorporating new studies published between 2003 and 2016. Methods: A copy of each paper cited in the literature review was obtained and checked against the evaporation rate reported in the review. If the expected value could not be found in the cited paper, other papers by the same author were consulted to see if the value had been reported elsewhere. A PubMed and Scopus database search was conducted to find papers published on tear evaporimetry since 2003. Results: Two new tables of TERs were created, based on the values reported by the original author. To aid in interpretation, the majority of results are expressed in units of x 10−7 g/cm2/sec. Where it was not possible to convert these values, some values are expressed as x 10−7 g/sec, x 10−7 g/sec/eye or W/min. Conclusions: Two new tables of TERs have been compiled to provide an accurate representation of the values reported in the original papers. These tables can be used as a point of reference for other researchers to compare their results.

Wong,S., Srinivasan,S., Murphy,P. J., Jones,L. Comparison of meibomian gland dropout using two infrared imaging devices Cont Lens Anterior Eye 2019;42(3):311-317 [ Show Abstract ]

Purpose: To measure the degree of meibomian gland (MG) dropout in the lower eyelid determined by analysis of images obtained from the LipiView II (LVII) and the Keratograph 5M (K5M).

Methods: The inferior eyelid of each participant was imaged in a random order using both devices. All images were subjectively assessed by a single-masked investigator to determine the extent of MG loss using the Arita 4-point meiboscore grading scale. The images were also semi-objectively analyzed with ImageJ to calculate the percentage of MG dropout, by tracing around the non-glandular area and the total exposed area of the lower lid.

Results: Twenty participants (mean age 37 years, range 23–60, 60% female) completed the study. A significant difference in meiboscore (mean ± SD) was obtained between the LVII and the K5M (1.43 ± 0.78 vs. 1.90 ± 0.81, Z = 3.25, p = 0.001). The meiboscore 95% limit of agreement (LOA) ranged from −1.88 to +0.93. A significant difference was found with mean ImageJ percentage dropout between the LVII and the K5M (31.5% vs 43.4%, t = −4.8, p = 0.00003). The percentage dropout 95% LOA ranged from −42.79% to +19.06%.

Conclusions: LVII images had significantly lower meiboscores and less percentage MG dropout. Varying amounts of dropout were observed between the devices due the amount of eyelid that was typically everted and because of differences in image quality. These results indicate that these devices should not be used interchangeably to evaluate MG dropout.

Woods,C. A. Working better with GPs: Lessons to be learned from a study of health care networks in the management of diabetes Clinical and Experimental Optometry 2005;891-2

Woods,C. A., Cumming,B. The impact of test medium on use of visual analogue scales Eye and Contact Lens 2009;35(1):6-10 [ Show Abstract ]

OBJECTIVES: Visual analog scales are frequently used as a means of allowing participants to rate symptoms during clinical trials. The accuracy and reproducibility of these scales play an important role in determining the experimental value of the data they provide. This study was initiated to compare the data collected using paper- and computer-based (Tablet PC) analog scales to better understand the variability in data provided by a visual analog scale. METHODS: Thirty participants rated ocular comfort, redness, and clarity of vision (right and left eyes) on a nondemarcated horizontal line on both paper and a Tablet PC. Measurements were taken in the morning between the hours of 8:30 and 10:30 am and again the same day between 2:30 and 4:30 pm. RESULTS: The mean difference between the measures recorded in the morning for the 2 media was 2.6 ± 0.9 (confidence intervals, 2 standard errors of the differences) units on a 100 unit scale, with the Tablet PC having the higher mean measure. The limits of agreement (2 standard deviations of the differences) was 9.4 units. Comparing the difference of the differences (1.0 ± 1.3) between the 2 methods of measure (morning vs. afternoon) the visual analog scales on the Tablet PC seemed to have good reproducibility of agreement in comparison with the paper version. CONCLUSIONS: Discrepancy analysis yielded no significant difference and slight bias between paper- and computer-based analog scales. Repeatability of measures using the Tablet PC was also demonstrated. These results suggest that the choice of medium does not significantly influence the outcome for subjective analog scales. © 2009 Lippincott Williams & Wilkins, Inc.

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.

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.

Woods,C., Naroo,S., Zeri,F., Bakkar,M., Barodawala,F., Evans,V., Fadel,D., Kalikivayi,L., Lira,M., Maseedupally,V., Trave Huarte,S., Eperjesi,F. Evidence for commonly used teaching, learning and assessment methods in contact lens clinical skills education Contact Lens Anterior Eye 2023;46(2):101821 [ Show Abstract ]

Introduction
Evidence based practice is now an important part of healthcare education. The aim of this narrative literature review was to determine what evidence exists on the efficacy of commonly used teaching and learning and assessment methods in the realm of contact lens skills education (CLE) in order to provide insights into best practice. A summary of the global regulation and provision of postgraduate learning and continuing professional development in CLE is included.

Method
An expert panel of educators was recruited and completed a literature review of current evidence of teaching and learning and assessment methods in healthcare training, with an emphasis on health care, general optometry and CLE.

Results
No direct evidence of benefit of teaching and learning and assessment methods in CLE were found. There was evidence for the benefit of some teaching and learning and assessment methods in other disciplines that could be transferable to CLE and could help students meet the intended learning outcomes. There was evidence that the following teaching and learning methods helped health-care and general optometry students meet the intended learning outcomes; clinical teaching and learning, flipped classrooms, clinical skills videos and clerkships. For assessment these methods were; essays, case presentations, objective structured clinical examinations, self-assessment and formative assessment. There was no evidence that the following teaching and learning methods helped health-care and general optometry students meet the intended learning outcomes; journal clubs and case discussions. Nor was any evidence found for the following assessment methods; multiple-choice questions, oral examinations, objective structured practical examinations, holistic assessment, and summative assessment.

Conclusion
Investigation into the efficacy of common teaching and learning and assessment methods in CLE are required and would be beneficial for the entire community of contact lens educators, and other disciplines that wish to adapt this approach of evidence-based teaching.

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.

Woods,J., Hutchings,N., Srinivasan,S., Jones,L. Geographic distribution of corneal staining in symptomatic dry eye Ocul Surf 2019;18(2):258-266 [ Show Abstract ]

Purpose
To describe the geographic distribution of corneal fluorescein staining across the five corneal zones, among non contact lens wearers who report symptoms of dry eye and determine which corneal zone most frequently exhibited the worst staining.

Methods
Prior studies conducted at the Centre for Ocular Research & Education, Canada, were reviewed for inclusion in the analysis. Each study assessed dry eye symptoms using OSDI and also assessed corneal fluorescein staining in five corneal zones. For each subject, the corneal zones were ranked 1–5 according to their relative staining grade, Rank-1 representing the highest grade.

Results
Data from 13 studies and 368 subjects were included. The total number of zones assigned Rank-1 (worst) staining was 449 (across 264 subjects). The inferior zone had the most Rank-1 counts of all zones at 193/43%, which involved 52.5% of all subjects. The nasal zone had 77/17% involving 20.9% of subjects, followed by the temporal (69/15.5%, 18.8% subjects) and superior zones (63/14%, 17.1% subjects). The central zone had the lowest count of Rank-1 designations, at only 47/10.5%, involving 12.8% of subjects. Bayesian analysis was used to generate distributions of the credible proportions of subjects likely to present with staining in a single peripheral zone, with or without central zone staining. It illustrated that staining in a peripheral zone without central staining was more credible. The worst single zone staining was most likely to present in the inferior zone (67.9%), followed by the nasal zone (11.3%), the superior zone (9.2%), and the temporal zone (5.6%).

Conclusion
In the presence of dry eye symptoms, the inferior zone typically presents the most severe grade of corneal staining, more likely without central zone staining. This knowledge is valuable when developing a strategy to treat dry eye signs, as the inferior corneal zone has the highest grade of staining thus has the potential to exhibit the greatest reduction in staining post-treatment.

Woods,J., Jones,D., Jones,L., Jones,S., Hunt,C., Chamberlain,P., McNally,J Ocular health of children wearing daily disposable contact lenses over a 6-year period Contact Lens Anterior Eye 2021;44(4):101391 [ Show Abstract ]

Purpose
To report on the ocular health and safety of children fit with soft hydrogel daily-disposable contact lenses, and followed for 6-years in a double-masked clinical trial investigating the performance of a dual-focus contact lens designed to control myopia progression.

Methods
Children aged 8−12 years, naïve to contact lens wear, were enrolled across four international sites. During years 1–3, children were randomised to either MiSight® 1 day or Proclear® 1 day (both omafilcon A, CooperVision, Inc.). The lenses were identical in material and geometry except for the front optical zone design. At the end of year-3, all those wearing Proclear 1 day were switched to MiSight 1 day, therefore all wore MiSight 1 day in years 4−6. Subjects agreed to wear the lenses at least 10-hours/day, 6-days/week. After dispensing, study visits were at 1-week, 1-month, 6-months and every 6-months until 6-years. At each visit, ocular measurements and subjective responses were recorded. Biomicroscopy used 0–4 grading scales; grade 0 represented no findings.

Results
144 children were enrolled: 69F:75M; mean age 10.1 years; mean cycloplegic spherical-equivalent refraction -2.11D; ethnicities included 34 East-Asian, 12 West-Asian, and 79 Caucasian. 92 completed the 6-years. Only three subjects discontinued due to an ocular adverse event (AE). No contact lens related AEs were classified as serious. The incidence rate of infiltrative AEs was 0.61% (6.1/1000 wearing-years; 95%CI: 0.24%–1.57%). The most common biomicroscopy findings were limbal, bulbar and tarsal hyperaemia and tarsal roughness. 99% of all biomicroscopy findings were grade-1 or lower. After 6-years of lens wear, ocular health by biomicroscopy was similar to pre-lens wear.

Conclusions
Across the 6-years, there were no contact lens related serious AEs and biomicroscopy showed no significant changes. Results suggest that children this age can successfully wear daily-disposable hydrogel contact lenses with minimal impact on ocular physiology.

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.

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.

Woods,J., Varikooty,J., Fonn,D., Jones,L. A novel scale for describing corneal staining Clinical Ophthalmology 2018;12:2369-2375 [ Show Abstract ]

The assessment of corneal staining is a commonly conducted procedure in both clinical practice and as part of various research studies. Different grading scales are employed by many clinicians and researchers to undertake this procedure for corneal staining comparisons between eyes, products and over time. This paper describes the development and use of a grading scale for corneal staining undertaken at an academic research site. The scale involves assessment of three factors across five corneal zones: type, area and depth. Staining type and area are graded on a 0–100 scale, and depth is graded on a 0–4 scale. These factors can be combined to create a three- or two-factor staining grade, or the factors may be reported individually. An additional benefit of this scale is that the staining scores may be reported by zone as “zone staining scores” or the scores of zones may be combined to provide an overall corneal “global staining score”.

Woods,J., Woods,C. A., Fonn,D. Early symptomatic presbyopes-What correction modality works best? Eye and Contact Lens 2009;35(5):221-226 [ Show Abstract ]

Purpose: To compare the performance of a low-addition silicone hydrogel multifocal soft lens with other soft lens correction options in a group of habitual soft lens wearers of distance correction who are symptomatic of early presbyopia. METHOD: This clinical study was designed as a prospective, double-masked, randomized, crossover, dispensing trial consisting of four 1-week phases, one for each of the correction modalities: a low-addition silicone hydrogel multifocal soft lens, monovision, habitual correction, and optimized distance visual correction. The prescriptions of all modalities were finalized at a single fitting visit, and the lenses were worn according to a randomized schedule. All lenses were made from lotrafilcon B material. A series of objective vision tests were conducted: high- and low-contrast LogMAR under high- and low-room lighting conditions, stereopsis, and critical print size. A number of other data collection methods used were novel: some data were collected under controlled laboratory-based conditions and others under "real-world" conditions, some of which were completed on a BlackBerry hand-held communication device. RESULTS: All participants were able to be fit with all four correction modalities. Objective vision tests showed no statistical difference between the lens modalities except in the case of low-contrast near LogMAR acuity under low-lighting levels where monovision (+0.29 ± 0.10) performed better than the multifocal (+0.33 ± 0.11, P=0.027) and the habitual (+0.37 ± 0.12, P<0.001) modalities. Subjective ratings indicated a statistically better performance provided by the multifocal correction compared with monovision, particularly for the vision associated with driving tasks such as driving during the daytime (93.3 ± 8.8 vs. 84.2 ± 23.7, P=0.05), at nighttime (88.8 ± 11.7 vs. 74.9 ± 23.6, P=0.001), any associated haloes or glare (92.0 ± 10.6 vs. 78.0 ± 22.8, P=0.003), and observing road signs (90.1 ± 11.8 vs. 79.4 ± 20.2, P=0.027). Preference for the multifocal compared with monovision was also reported when watching television (95.0 ± 6.4 vs. 82.6 ± 20.1, P=0.001) and when changing focus from distance to near (87.0 ± 13.4 vs. 66.1 ± 32.2, P<0.001). CONCLUSIONS: For this group of early presbyopes, the AIR OPTIX AQUA MULTIFOCAL-Low Add provided a successful option for visual correction, which was supported by the results of subjective ratings, many of which were made during or immediately after performing such activities as reading, using a computer, watching television, and driving. These results suggest that making a prediction of "success or not" based on consulting room acuity tests alone is probably unwise. Copyright © Contact Lens Association of Ophthalmologists, Inc.

Woods,J., Woods,C., Fonn,D. Visual performance of a multifocal contact lens versus monovision in established presbyopes Optometry and Vision Science 2015;92(2):175-82 [ Show Abstract ]

PURPOSE: To compare subjective and objective visual performance of the Air Optix Aqua Multifocal lens to monovision in a group of subjects requiring a medium level of reading-addition power.

METHODS: Fifty participants with reading additions between 1.25 and 2.00 diopters (inclusive) were randomized into a prospective, crossover clinical trial. They wore monovision and multifocals for 2 weeks in a randomized order. High- and low-contrast logMAR (logarithm of the minimum angle of resolution) acuity and stereopsis were measured at the beginning and end of each period. During each phase, participants performed specific tasks followed by subjective rating surveys and also completed satisfaction rating surveys on days 3, 7, and 12; all were transferred in real time using BlackBerry smartphones. A general rating survey was completed at the dispensing and 2-week visits.

RESULTS: Forty-nine participants completed the study (mean age, 52 years). Distance and near high- and low-contrast acuities were significantly better (p < 0.05) with monovision at all visits. High-contrast intermediate acuity was only better (p < 0.05) with multifocals after 2 weeks. Stereopsis was equivalent after 2 weeks, but better (p < 0.05) with multifocals at dispensing. Subjective ratings were generally equivalent between modalities although there was a trend for multifocals to be rated higher for focus changing and driving, whereas monovision tended to be rated higher for near tasks. For both corrections, the satisfaction survey showed no significant change between days 3, 7, and 12, and the general survey showed that comfort was maintained but subjective vision ratings decreased significantly over the 2 weeks. Twenty-five participants (51%) preferred multifocals, 18 (37%) preferred monovision, and the remaining 6 (12%) declared both unacceptable.

CONCLUSIONS: In this cohort, distance and near acuities were better with monovision, whereas the subjective ratings tended to favor the Air Optix Aqua Multifocal, with the exception of near performance. Preference was statistically similar between both corrections, with a trend toward preferring the multifocal.

Wu,T.-Y., Huang,C.-C., Tsai,H.C., Lon,T.-K., Chen,P.-Y., Darge,H. F., Hong,Z.-X., Ham,H.-J., Lin,S.-Z., Lai,J.-Y., Chen,Y.-S. Mucin-mediated mucosal retention via end-terminal modified Pluronic F127-based hydrogel to increase drug accumulation in the lungs Biomaterials Advances 2024;Jan(156):213722 [ Show Abstract ]

Noninvasive lung drug delivery is critical for treating respiratory diseases. Pluronic-based copolymers have been used as multifunctional materials for medical and biological applications. However, the Pluronic F127-based hydrogel is rapidly degraded, adversely affecting the mechanical stability for prolonged drug release. Therefore, this study designed two thermosensitive copolymers by modifying the Pluronic F127 terminal groups with carboxyl (ADF127) or amine groups (EDF127) to improve the viscosity and storage modulus of drug formulations. β-alanine and ethylenediamine were conjugated at the terminal of Pluronic F127 using a two-step acetylation process, and the final copolymers were characterized using 1H nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectra. According to the 1H NMR spectra, Pluronic F127 was functionalized to form ADF127 and EDF127 with 85 % and 71 % functionalization degrees, respectively. Rheological studies revealed that the ADF127 (15 wt%) and EDF127 (15 wt%) viscosities increased from 1480 Pa.s (Pluronic F127) to 1700 Pa.s and 1800 Pa.s, respectively. Furthermore, the elastic modulus of ADF127 and EDF127 increased, compared with that of native Pluronic F127 with the addition of 5 % mucin, particularly for ADF127, thereby signifying the stronger adhesive nature of ADF127 and EDF127 with mucin. Additionally, ADF127 and EDF127 exhibited a decreased gelation temperature, decreasing from 33 °C (Pluronic F127 at 15 wt%) to 24 °C. Notably, the in vitro ADF127 and EDF127 drug release was prolonged (95 %; 48 h) by the hydrogel encapsulation of the liposome-Bdph combined with mucin, and the intermolecular hydrogen bonding between the mucin and the hydrogel increased the retention time and stiffness of the hydrogels. Furthermore, ADF127 and EDF127 incubated with NIH-3T3 cells exhibited biocompatibility within 2 mg/mL, compared with Pluronic F127. The nasal administration method was used to examine the biodistribution of the modified hydrogel carrying liposomes or exosomes with fluorescence using the IVIS system. Drug accumulation in the lungs decreased in the following order: ADF127 > EDF127 > liposomes or exosomes alone. These results indicated that the carboxyl group-modified Pluronic F127 enabled well-distributed drug accumulation in the lungs, which is beneficial for intranasal administration routes in treating diseases such as lung fibrosis.

Xu,M., Sivak,J. G., McCanna,D. J. Ocular toxicology: synergism of UV radiation and benzalkonium chloride
Cutaneous and Ocular Toxicology 2020;39(4):370-379 [ Show Abstract ]

Purpose: To investigate the combined toxic effect of ultraviolet (UV) radiation and benzalkonium chloride (BAK), a common preservative in ophthalmic eye drops, on human corneal epithelial cells (HCEC).

Methods: Cultured HCEC were exposed to different combined and separate UV (280-400 nm) and BAK solutions at relevant human exposure levels. Human exposure to UV can occur before, during, or after eye drop installation, therefore, three different orders of ocular exposures were investigated: UV and BAK at the same time, UV first followed by BAK, and BAK first followed by UV. Control treatments included testing HCEC exposed to BAK alone and also HCEC exposed to UV alone. In addition, phosphate-buffered saline (PBS) was used as a negative control. After exposure, cell metabolic activity of the cultures was measured with PrestoBlue, and cell viability was determined using confocal microscopy with viability dyes.

Results: BAK alone reduced the metabolic activity and cell viability of HCEC in a dose- and time-dependent manner. UV alone at a low dose (0.17 J/cm2) had little toxicity on HCEC and was not significantly different from PBS control. However, UV plus BAK showed combined effects that were either greater than (synergistic) or equal to (additive) the sum of their individual effects. The synergistic effects occurred between low dose UV radiation (0.17 J/cm2) and low concentrations of BAK (0.001%, 0.002%, 0.003%, and 0.004%).

Conclusions: This investigation determined that at relevant human exposure levels, the combination of UV radiation (280-400 nm) and BAK can cause synergistic and additive toxic effects on human corneal epithelial cells. This finding highlights the importance of considering the combined ocular toxicity of BAK and solar radiation in the risk assessment of BAK-preserved ophthalmic solutions.

Xu,M., Sivak,J. G., McCanna,D. J. Neutralization of the eye and skin irritant benzalkonium chloride using UVC radiation Cutaneous and Ocular Toxicology 2021;40(2):78-84 [ Show Abstract ]

Benzalkonium chloride (BAK) is a widely used disinfectant and preservative which is effective against a wide range of viruses (e.g. SARS-CoV and SARS-CoV-2), bacteria and fungi. However, it is toxic to the eye and skin. This study investigated the neutralization of BAK using ultraviolet C (UVC) radiation as an effort to reduce BAK toxicity potential.

Methods
BAK solutions were irradiated with a germicidal UVC lamp at various doses. Human corneal epithelial cells (HCEC) were then exposed to the UVC-irradiated BAK solutions for 5 minutes. After exposure, the cultures were assessed for metabolic activity using PrestoBlue; for cell viability using confocal microscopy with viability dyes; and for tight junction proteins using immunofluorescence staining for zonula occludens (ZO)-1.

Results
UVC radiation reduced BAK toxicity on cell metabolic activity in a dose-dependent manner. When the solution depth of BAK was 1.7 mm, the UVC doses needed to completely neutralize the toxicity of BAK 0.005% and 0.01% were 2.093 J/cm2 and 8.374 J/cm2, respectively. The cultures treated with UVC-neutralized BAK showed similar cell metabolic activity and cell viability to those treated with phosphate buffered saline (PBS) (p = 0.806 ∼ 1.000). The expression of ZO-1 was greatly disturbed by untreated BAK; in contrast, ZO-1 proteins were well maintained after exposure to UVC-neutralized BAK.

Conclusions
Our study demonstrates that the cell toxicity of BAK can be neutralized by UVC radiation, which provides a unique way of detoxifying BAK residues. This finding may be of great value in utilizing the antimicrobial efficacy of BAK (e.g. fighting against SARS-CoV-2) while minimizing its potential hazards to human health and the environment.

Yamasaki,K., Dantam,J., Sasanuma,K., Hisamura,R., Mizuno,Y., Hui,A., Jones,L. Impact of in vitro lens deposition and removal on bacterial adhesion to orthokeratology contact lenses Contact Lens Anterior Eye 2023;Online ahead of print [ Show Abstract ]

Purpose
The purpose of this study was to explore the impact of several contact lens (CL) care solutions on the removal of proteins and lipids, and how deposit removal impacts bacterial adhesion and solution disinfection.

Methods
Lysozyme and lipid deposition on three ortho-k (rigid) and two soft CL materials were evaluated using an ELISA kit and gas chromatography respectively. Bacterial adhesion to a fluorosilicone acrylate material using Pseudomonas aeruginosa with various compositions of artificial tear solutions (ATS), including with denatured proteins, was also investigated. The impact of deposition of the different formulations of ATS on biofilm formation was explored using cover slips. Finally, the lysozyme and lipid cleaning efficacy and disinfection efficacy against P. aeruginosa and Staphylococcus aureus of four different contact lens care solutions were studied using qualitative analysis.

Results
While maximum lysozyme deposition was observed with the fluorosilicone acrylate material (327.25 ± 54.25 µg/lens), the highest amount of lipid deposition was recorded with a fluoro-siloxanyl styrene material (134.71 ± 19.87 µg/lens). Adhesion of P. aeruginosa to fluorosilicone acrylate lenses and biofilm formation on cover slips were significantly greater with the addition of denatured proteins and lipids. Of the four contact lens care solutions investigated, the solution based on povidone-iodine removed both denatured lysozyme and lipid deposits and could effectively disinfect against P. aeruginosa and S. aureus when contaminated with denatured proteins and lipids. In contrast, the peroxide-based solution was able to inhibit P. aeruginosa growth only, while the two multipurpose solutions were unable to disinfect lenses contaminated with denatured proteins and lipids.

Conclusion
Bacterial adhesion and biofilm formation is influenced by components within artificial tear solutions depositing on lenses, including denatured proteins and lipids, which also affects disinfection. The ability of different solutions to remove these deposits should be considered when selecting systems to clean and disinfect ortho-k lenses.

Yamasaki,K., Drolle,E., Nakagawa,H., Hisamuare,R., Ngo,W., Jones,L. W. Impact of a low molecular weight hyaluronic acid derivative on contact lens wettability Cont Lens Anterior Eye 2021;44(3):101334 [ Show Abstract ]

Purpose
To investigate the interaction of a novel low molecular weight hyaluronic acid derivative containing hydrophobic groups with soft contact lenses and its effect on lens hydrophilicity compared with a conventional form of hyaluronic acid.

Methods
This investigation studied the uptake of fluorescently-labelled hyaluronic acid and a low molecular weight hyaluronic acid derivative to four types of contact lenses using fluorescent microscopy and confocal laser scanning microscopy. Further, the four lens types were used to compare efficacy in improving hydrophilicity, as well as maintenance of contact angle measurements, in commercially available multipurpose solutions that contained either hyaluronic acid, the low molecular weight hyaluronic acid derivative, or an alternative wetting agent.

Results
The low molecular weight hyaluronic acid derivative was found to sorb more readily to silicone hydrogel lenses and exhibit a greater accumulation over time than conventional hyaluronic acid. Multipurpose solutions containing the low molecular weight hyaluronic acid derivative showed an increase in lens hydrophilicity through decreases in contact angle measurements when compared with those obtained from lenses treated with multipurpose solutions containing conventional hyaluronic acid or alternative wetting agents. This increase in lens hydrophilicity associated with the low molecular weight hyaluronic acid derivative was also maintained over multiple cycles in phosphate buffered saline, while alternative solutions with conventional hyaluronic acid did not.

Conclusion
Overall, lens treatment using a low molecular weight hyaluronic acid derivative-based solution lead to improved in vitro lens hydrophilicity.

Yamasaki,K., Mizuno,Y., Kitamura,Y., McCanna,D. J., Ngo,W., Jones,L. W. The efficacy of povidone-iodine, hydrogen peroxide and a chemical multipurpose contact lens care system against Pseudomonas aeruginosa on various lens case surfaces Cont Lens Anterior Eye 2021;44(1):18-23 [ Show Abstract ]

Purpose
To determine the antimicrobial efficacy of a povidone-iodine system (PVP-I; cleadew, OPHTECS Corporation, Kobe, Japan), a peroxide system (AOSEPT Plus with HydraGlyde, Alcon, Fort Worth, TX), and a chemical multipurpose system (renu fresh, Bausch & Lomb, Rochester, NY) on contact lens case surfaces that are both in contact and not in contact with the solutions during lens disinfection.

Methods
The surfaces of the inner walls, underside of the lid, and lens holder (if applicable) of the cases were inoculated with P. aeruginosa ATCC 27853. The cases were disinfected with the solutions as per their manufacturer instructions. After disinfection, the inoculated surfaces were swabbed and the amount of surviving P. aeruginosa was determined. Following this experiment, separate cases were inoculated and disinfected as before. This time the cases were agitated after recommended disinfection time and the amount of P. aeruginosa in the disinfecting solution was quantified immediately, and again after resting for 7 days. Experiments were conducted in triplicate (n = 3).

Results
Units are expressed in log CFU. All three solutions significantly reduced P. aeruginosa on direct-contact surfaces (all p < 0.039). On non-contact surfaces, the reduction of P. aeruginosa in the PVP-I system (pre-disinfection: 6.8 ± 0.5, post-disinfection: 1.0 ± 0.0; p < 0.001) was significant, but not for the hydrogen peroxide system (pre-disinfection: 6.3 ± 0.6, post: 5.5 ± 0.5; p = 0.194) and the chemical multipurpose system (pre-disinfection: 6.6 ± 0.1, post-disinfection: 5.6 ± 0.8; p = 0.336). After 7 days post-disinfection, no P. aeruginosa regrowth was observed in the PVP-I system (Day 1: 1.0 ± 0.0, Day 7: 1.0 ± 0.0; p = 1) and the chemical multipurpose system (Day 1: 4.2 ± 0.2, Day 7: 1.8 ± 0.9; p = 0.012), however regrowth was observed in the hydrogen peroxide system (Day 1: 3.4 ± 0.6, Day 7: 6.1 ± 0.4; p = 0.003).

Conclusion
The PVP-I system was more effective against P. aeruginosa on non-contact surfaces than the hydrogen peroxide system or the chemical multipurpose system and is capable of inhibiting regrowth of P. aeruginosa for at least 7 days post-disinfection.

Yang,M., Luensmann,D., Fonn,D., Woods,J., Jones,D., Gordon,K., Jones,L. Myopia prevalence in Canadian school children: A pilot study Eye 2018;32(6):1042-1047 [ Show Abstract ]

Purpose: A pilot study to determine the prevalence of myopia, proportion of uncorrected myopia and pertinent environmental factors among children in a suburban region in Canada. Methods: Refraction with cycloplegia and ocular biometry were measured in children of two age groups. Myopia was considered at a spherical equivalent refraction (SER) ≤-0.50 D in at least one eye. Parents completed a questionnaire that captured the child's daily activities. Results: A total of 166 children completed the study (83 aged 6-8 and 83 aged 11-13). Myopia prevalence was 17.5% among the overall group, 6.0% among ages 6-8 and 28.9% among ages 11-13. Mean subjective SER in myopic children was -1.10 D (95% confidence interval (CI), -0.34 to -1.86 D) at ages 6-8 and -2.44 D (95% CI, -1.71 to -3.18 D) at ages 11-13. In this study, 34.5% of the myopic children were uncorrected, which represented 6.0% of the entire group of children. Mean axial length (AL) increased by 1.03 mm from ages 6-8 (mean 22.62 mm; 95% CI, 22.45 to 22.79 mm) to ages 11-13 (mean 23.65 mm; 95% CI, 23.45 to 23.84 mm; p < 0.01). The correlation coefficient between AL and SER was -0.618 (p < 0.01). Binary logistic regression between outdoor time and the prevalence of myopia showed that one additional hour of outdoor time per week lowered the odds of a child having myopia by 14.3% (p = 0.007). Conclusion: Myopia prevalence increased from 6% at ages 6-8 to 29% at ages 11-13. Thirty-five per cent of the myopes in this study were uncorrected. More time outdoors may be beneficial to protect against myopia onset.