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

Ngo,W., Srinivasan,S., Jones, L., A comparison of dry eye diagnostic tests between symptomatic and asymptomatic age-matched females Eye and Contact Lens 2018;44(Suppl 1):S110-S114 [ Show Abstract ]

PURPOSE: To quantify the strength of association of dry eye (DE) symptoms to DE diagnostic tests in age-matched females.
METHODS: Twenty females with DE symptoms (Ocular Surface Disease Index, OSDI, ≥13) were age-matched with 20 females without DE symptoms (OSDI<13) in this cross-sectional study. Noninvasive tear breakup time (NIBUT), ocular staining, meibum quality, number of obstructed meibomian glands (MGs), lid wiper epitheliopathy, Marx line placement, eyelid margin score, Schirmer test, meibography, and visual acuity were assessed in both groups.
RESULTS: Twenty participant pairs completed the study. The age (median/interquartile range [IQR]) of the symptomatic group was 60/15 and the asymptomatic group was 62/15. The tests (median/IQR, P value) that were significantly different between the symptomatic group and the asymptomatic group were OSDI (35.4/35.4 vs. 3.1/6.7, P<0.01), NIBUT (2.1/0.7 sec vs. 3.0/3.0 sec, P=0.01), meibum quality (3.0/0.0 grade units vs. 2.0/1.0 grade units, P<0.01), number of obstructed MGs (7.0/2.0 glands vs. 5.0/4.8 glands, P<0.01), and ocular staining (5.5/3.8 grade units vs. 0.5/1.0 grade units, P<0.01). The tests (area under curve, [AUC], odds ratio [OR]) that were most strongly associated with DE symptoms were ocular staining (0.93, 5.0), number of obstructed MGs (0.79, 2.6), meibum quality (0.76, 2.4), and NIBUT (0.74, 3.2) (all P0.05), and similarly, no significant association to DE symptoms (all P>0.05).
CONCLUSION: The diagnostic tests most strongly associated with DE symptoms in older women were ocular staining, meibum quality, number of obstructed MGs, and tear film stability.

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.

Ngo,W., Srinivasan,S., Jones,L. An Eyelid Warming Device for the Management of Meibomian Gland Dysfunction J Optom 2019;12(2):120-130 [ Show Abstract ]

PURPOSE: To determine the effectiveness of the MGDRx EyeBag in managing meibomian gland dysfunction.

METHODS: This was a prospective, randomized, controlled, observer-masked, bilateral eye study that enrolled 29 participants. Participants were randomized into either the EyeBag group or the control group. The EyeBag group used the EyeBag 10minutes 2x/day, and the control group remained on their own dry eye treatment regimen (if applicable). All participants were observed at baseline, 2 weeks (2wk) and 4 weeks (4wk). At 4wk, participants in the EyeBag group were asked to stop using the EyeBag. All participants were seen again at 8 weeks (8wk). Primary outcomes were the Ocular Surface Disease Index (OSDI), Current Symptoms Questionnaire (CSQ), meibomian gland score (MG score), and non-invasive tear breakup time (NIBUT).

RESULTS: Twenty-five participants completed the study (mean age 38±15 years, 7 male). There was a significant change in OSDI over time for the EyeBag group (mean[lower 95% CI, upper 95% CI], baseline: 39.1[31.1,47.0], 2wk: 26.8[19.7,33.9], 4wk: 26.6[16.5,36.7], 8wk: 27.7[18.4,37.0]; p=0.01), but not in the control group (p=0.22), but no significant difference between groups at all time points (all p>0.27). Symptoms immediately improved after conducting the EyeBag based on at-home CSQ scores (Δ=-5.0 points, p<0.01), but not in the control group. For both groups, there was no significant change (p-value EyeBag,p-value control) in MG score (0.21,0.17) and NIBUT (0.49,0.06) over time.

CONCLUSIONS: The EyeBag may relieve symptoms of dry eye, but the effect on meibomian gland function and tear stability when used for only 4 weeks was undetectable.

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., 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.

Nichols,J. J., Chalmers,R. L., Dumbleton,K., Jones,L., Lievens,C. W., Merchea,M. M., Szczotka-Flynn,L. The Case for Using Hydrogen Peroxide Contact Lens Care Solutions: A Review Eye & Contact Lens 2019;45(2):69-82 [ Show Abstract ]

Despite their established disinfection and safety benefits, the use of hydrogen peroxide (H2O2) lens care systems among today's wearers of reusable contact lenses remains low in comparison with multipurpose solution (MPS) use. Multipurpose solution systems, however, present several potential drawbacks that may impact patient outcomes, including the use of chemical preservatives for disinfection, biocompatibility issues, and challenges with respect to lens care compliance. Given their unique composition and mechanism of action, one-step H2O2 systems offer the opportunity to avoid many of the challenges associated with MPS use. This article reviews the evolution of H2O2 lens care systems and examines the current scientific and clinical evidence regarding the relative ease of use, lens and tissue compatibility, disinfection efficacy, and ocular surface safety of H2O2 systems. Evaluation of the available data indicates that in comparison with MPS, one-step H2O2 systems tend to promote more favorable compliance, efficacy, comfort, and ocular surface outcomes for a wide range of contact lens–wearing patients. Based on the current published evidence, the authors recommend that eye care practitioners consider making one-step H2O2 systems their first-line contact lens care recommendation for most wearers of reusable lenses.

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., Jones,L., Morgan,P. B., Efron,N. Bibliometric analysis of the meibomian gland literature Ocular Surface 2021;20(April):212-214 [ Show Abstract ]

There is a rich history of interest in the sebaceous glands located posterior to the tarsal plates in the eyelids, to which we refer today as the meibomian glands (MGs). Although there is acknowledgement of the MGs preceding the work of Johann Heinrich Meibom in the 1600's, he is credited with advancing our knowledge and study of these glands.

The MGs produce a distinct lipid secretion (‘meibum’) made up of a variety of lipid classes, mostly composed of nonpolar wax and cholesterol esters, although other nonpolar and polar lipids are certainly known to exist in the meibum. The normal function of meibum is to make its way to the tear film lipid layer, ultimately forming a resistive barrier to evaporation of the aqueous component of the tear film. In disease, the MGs lose their ability to secrete a normal meibum composition and/or are impeded due to factors such as atrophy of the MGs, keratinization of the orifice of the gland from which the meibum is secreted onto the eyelid margin, or bacterial colonization of the eyelid, altering the secretion itself once expressed. These conditions today are known as blepharitis, including anterior and posterior blepharitis (which includes meibomian gland dysfunction).

Given the extensive study of MGs, a bibliometric analysis is warranted to acknowledge and celebrate those contributing to this important part of ophthalmic research.

Nichols,J. J., Jones,L., Morgan,P. B., Efron,N. Bibliometric analysis of the orthokeratology literature Contact Lens Anterior Eye 2021;44(4):101390 [ Show Abstract ]

The wearing of rigid lenses can result in changes to corneal curvature and the planned, temporary reduction of myopia by wearing flat-fitting rigid lenses (termed orthokeratology) was first reported in the 1960’s [1]. In the late 1970’s and early 1980’s, several studies evaluated this concept and concluded that the reduction in myopia was relatively short-lived, unpredictable, inconsistent and limited to only a low degree of myopia; as such, orthokeratology was largely ignored at this time [2, 3, 4].
A renewed interest in orthokeratology occurred in the late 1990’s and early 2000’s due to the simultaneous development of corneal topographers, highly oxygen permeable rigid lens materials and the development of sophisticated reverse geometry lenses that produced more predictable reductions in myopia [5, 6, 7, 8, 9]. This permitted contact lens fitters to adopt the concept of ‘overnight orthokeratology’, where patients wore the lenses during sleep and corneal shape changes occurred that reduced the degree of myopia to the point where the patient could remove the lens on waking and spend several days with no vision correction being required [10,11].
In 2005, Cho and colleagues reported that orthokeratology lenses used in children could slow the progression of myopia and this observation resulted in a resurgence in interest in orthokeratology [12]. Numerous publications since have shown that this myopia control effect is repeatable and many practitioners now adopt this modality on a routine basis to slow the progression of myopia, particularly in Asian countries [9,13, 14, 15, 16, 17].
The purpose of this paper is to report a bibliometric analysis of the literature on orthokeratology lenses so as to determine the most widely cited papers and most prolific authors, institutions, countries and journals related to this topic, and to recognise and celebrate the key stakeholders in this area of contact lens research.

Nichols,J. J., Morgan,P. B., Jones,L. W., Efron, N Bibliometric Analysis of Ophthalmic Journals JAMA Ophthalmology 2023;141(7):651-657 [ Show Abstract ]

KEY POINTS
Question: What articles, journals, authors, institutions, and countries in the ophthalmic literature are the most highly cited and prolific and have the highest h-index for ophthalmic journal articles?

Findings: In this qualitative study, the h-index for ophthalmic journal articles was determined to be 494, which appeared comparable with the journal literature of other medical disciplines.

Meaning: While these analyses excluded ophthalmology articles in general medical journals, they suggest a strong ophthalmic research base underpins eye care, with ophthalmology having the highest h-index across a range of ophthalmic and vision disciplines contributing to this literature.

ABSTRACT
Importance: The primary vehicle for reporting and testing advances in eye care is refereed ophthalmic journals, which can be characterized using targeted bibliometric analyses.

Objective: To identify all ophthalmic journals and evaluate citation metrics relating to articles, journals, authors, institutions, and countries published therein.

Design and Setting: A bibliometric analysis was undertaken of all ophthalmic journals included in the Scopus database (Elsevier). The search was restricted to all article types published in ophthalmic journals in English from inception through November 18, 2022. After excluding general medical journals, journals published in a language other than English, and spurious titles unrelated to the ophthalmic field, the Scopus database was found to list 335 ophthalmic journal titles that have published 471 184 articles, constituting the data set for this analysis. The 20 most highly cited articles were identified. Rank-order lists by article count were assembled for journals, authors, institutions, and countries.

Main Outcomes and Measures: An h-index for ophthalmic journal articles was derived from citations and article counts for each constituent of each category.

Results: The h-index for ophthalmic journal articles was determined to be 494. The journal with the highest h-index was Ophthalmology (h-index, 297). The journal with the greatest number of articles was American Journal of Ophthalmology (38 441 articles). The most highly cited article was by Quigley and Broman, 2006 (5147 citations), concerning the epidemiology of glaucoma. The author with the highest h-index for ophthalmic journal articles was Ronald Klein, MD (h-index, 126), and the most prolific was Carol L. Shields, MD (1400 articles). Johns Hopkins University (h-index, 215) was the institution with the highest h-index for ophthalmic journal articles, and Harvard University was the most prolific (10 071 articles). The United States was the nation with the highest h-index for ophthalmic journal articles (h-index, 444) and was the most prolific (180 017 articles).

Conclusions and Relevance: In this study, the most highly cited articles published in ophthalmic journals were revealed, as well as the leading journals, authors, institutions, and countries. While excluding ophthalmology articles in general medical journals, this investigation affords a means of identifying highly cited authors, institutions, and countries which individuals or institutions can use as a guide regarding contributions to the field.

Nichols,J. J., Morgan,P. B., Jones,L. W., Efron, N The history of optometry journals from a bibliometric perspective Hindsight 2023;54(2):36-43 [ Show Abstract ]

The rich history of optometric journal publications has been well documented, but the scientific impact of all optometry journals over all time has not been published. This work aims to determine the most impactful papers, authors, institutions and countries publishing in optometry journals. A h-index for “optometry journal publications” (the “hOJP-index”) was derived for each constituent of each category to serve as a measure of impact. The hOJP-index for the 34,565 papers published in all optometry journals is 136; these papers have been cited 294,239 times. Optometry and Vision Science is the most impactful and prolific journal (hOJP=118; n=13,095 papers). The most highly cited paper, by Richard Armstrong, is entitled “When to use the Bonferroni correction” (1,172 citations). Australian optometrist Nathan Efron is the most impactful and prolific author (hOJP=41; n=273). UNSW Sydney and the University of California, Berkeley are the most impactful institutions (both hOJP=58), and UNSW Sydney is the most prolific (n=963). The most impactful and prolific nation is the United States (hOJP=109; n=12,050). This quantitative bibliometric analysis demonstrates an impactful optometric research base enshrined in optometry journals.

Nichols,J. J., Morgan,P. M., Efron,N, Jones,L. W. Global optometrist research ranking derived from a science-wide author database of standardised citation indicators Clinical and Experimental Optometry 2022;105(1):20-25 [ Show Abstract ]

Clinical relevance
Publications in refereed scientific journals provide a rigorous research base that underpins clinical optometric practice. Leading optometrists who generate this literature can be identified and ranked using standardised citation indicators.

Background
This work seeks to identify and rank all optometrists included in a Science-Wide author database of standardised citation indicators (S-W) and to compare this ranking with the Global Optometrist Top 200 Research Ranking (T200).

Methods
A search was conducted for the names of all optometrists in the T200 who were included in the S-W, which is a world-wide listing of the top 2% of scientists in each of 174 subfield disciplines, ranked according to a composite citation indicator (cns) that excludes self-citations and corrects for multiple authorships and author order.

Results
The names of 66 optometrists are found in the S-W. Of these, 58 are designated as working in the primary sub-field ‘Ophthalmology & Optometry’; this listing, in rank-order of cns, is referred to as the ‘S-W-derived Optometrist Research Ranking’ (S-WORR). Australian optometrist Nathan Efron is ranked #1 in the S-WORR. The number (%) of optometrists in the S-WORR from each country is: the United States – 26 (45%), Australia – 12 (21%), the United Kingdom – 11 (19%), Canada – 5 (9%), Spain – 2 (3%), Hong Kong – 1 (2%) and South Africa – 1 (2%). The universities housing the equal highest number of optometrists in the S-WORR (five each) are the University of California, Berkeley, USA; the University of New South Wales, Australia; and Queensland University of Technology, Australia. There is a moderately strong correlation between T200 and S-WORR rankings (ρ = 0.6017, N = 58, p < 0.0001).

Conclusions
The S-WORR represents an elite cohort of optometrists who ought to be celebrated for their outstanding, leading and impactful contributions to optometric research.

Nichols,J. J., Morgan,P. M., Jones,L. W., Efron,N 21st century bibliometric analysis of the field of dry eye disease Clinical and Experimental Optometry 2021;104(5):639-640 [ Show Abstract ]

In 2012, the lead author of this paper (JJN) conducted a citation analysis of dry eye research to identify the leading papers, authors, institutions, countries and journals in the field. That analysis was essentially an historical overview of publications on this topic extending back over the past century. Because a strong and growing foundation of scientific literature is a fundamental component of evidenced-based clinical care of patients, the current work was conducted to update the research community on trends in the 21st century dry eye literature, and to compare this new literature with the prior analysis in the context of events or trends in the dry eye field.

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

Nichols,K. K., Redfern,R. L., Jacob,J. T., Nelson,J. D., Fonn,D., Forstot,S. L., Huang,J. -F, Holden,B. A., Nichols,J. J. The TFOS International Workshop on Contact Lens Discomfort: Report of the definition and classification subcommittee Investigative Ophthalmology and Visual Science 2013;54(11):TFOS14-TFOS19

Oh,S., McCanna,D., Subbaraman,L.N., Jones,L. Cytotoxic and inflammatory effects of contact lens solutions on human corneal epithelial cells in vitro Contact Lens and Anterior Eye 2018;41(3):282-289 [ Show Abstract ]

Purpose: To ascertain the effect that four contact lens (CL) multipurpose solutions (MPS) have on the viability and release of pro-inflammatory cytokines from human corneal epithelial cells (HCEC). Methods: HCEC were exposed to four different MPS at various concentrations for 18 hours. The cells were also exposed to phosphate buffer, borate buffer, and PHMB. The cell viability was evaluated using the alamarBlue assay. The release of pro-inflammatory cytokines was measured using a Multiplex electrochemiluminescent assay. Results: MPS-A, MPS-B and MPS-C all reduced cell metabolic activity p < 0.05 from control with MPS-A showing the greatest cytotoxic effect (maximum reduction, 90.6%). In contrast, MPS-D showed no significant reductions in cytotoxicity except at the highest concentration tested (19% reduction at 20% MPS concentration). Of the four cytokines evaluated MPS-C showed a substantial increase in the release of IL-1β, IL-6, IL-8, and TNF-α at higher concentrations when compared to control p < 0.05. At the 20% concentration of MPS-A and MPS-B the release of IL-1 β increased p 0.05. Exposing the cells to borate buffer and PHMB caused an increase in the release of TNF-α p < 0.05. Conclusions: This investigation demonstrates that at different concentration levels, several of the MPS tested showed a decrease in viability and an increase in the release of inflammatory cytokines from HCEC. The borate buffer component as well as PHMB appears to contribute to this pro-inflammatory reaction.

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. 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.

Omali,N. B., Lada,M., Lakkis,C., Morgan,P. B., Nichols,J. J., Subbaraman,L. N., Jones,L. W. Lipid Deposition on Contact Lenses when Using Contemporary Care Solutions Optometry and Vision Science 2017;94(9):919-927 [ Show Abstract ]

SIGNIFICANCE There remains only a small amount of data from human studies demonstrating the effect of contact lens/lens care solution combinations on the deposition of lipids. Therefore, information on the degree to which modern materials deposit lipids when used with contemporary care solutions would be valuable. PURPOSE The present study aims to determine the effect of lens care system combinations on levels of total lipid, cholesterol, and cholesteryl esters extracted from three different contact lenses (CLs) when used with four contemporary care systems. METHODS Experienced CL wearers were recruited to participate in this study. Combinations of three CLs (etafilcon A [ETA], galyfilcon A [GALY], and senofilcon A [SENO]) and four CL care solutions (Biotrue, ClearCare, OPTI-FREE PureMoist, and RevitaLens Ocutec) were investigated. A total of 791 CLs were analyzed. Subjects were randomized to one lens type and then used all four lens care solutions in random sequence for 10-14 days before the CLs were collected and analyzed for the amount of cholesterol, cholesteryl esters, and total lipids. RESULTS The mean range of cholesterol recovered across the different care solutions was 0.34-2.77 µg/lens, 3.48-4.29 µg/lens, and 4.75-6.20 µg/lens for ETA, SENO, and GALY lenses, respectively. Use of OPTI-FREE PureMoist with ETA lenses led to a significantly greater amount of cholesterol being recovered when compared to the use of the other solutions with ETA lenses (P .05). CONCLUSIONS This study did not demonstrate conclusively that any of the solution/CL combinations were superior to any of the other combinations when the amounts of lipid deposition were compared among the tested lenses. © Lippincott Williams & Wilkins.

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.

Omali,N. B., Subbaraman,L. N., Heynen,M., Fadli,Z., Coles-Brennan,C., Jones,L. W. In Vitro Effect of Lysozyme on Albumin Deposition to Hydrogel Contact Lens Materials Optometry and Vision Science 2017;94(11):1047-1051 [ Show Abstract ]

SIGNIFICANCE: Albumin deposition on contact lenses could be detrimental to contact lens (CL) wear because this may increase the risk of bacterial binding and reduce comfort. Lysozyme deposition on selected lens materials would reduce albumin deposition on lenses. PURPOSE: This study aims to determine if lysozyme deposition on CLs could act as a barrier against subsequent albumin adsorption, using an in vitro model. METHODS: Six hydrogel CL materials (etafilcon A, polymacon, nelfilcon A, omafilcon A, ocufilcon B, and nesofilcon A) were evaluated. Four CLs of each type were soaked in lysozyme solution for 16 hours at 37°C. Lysozyme-coated lenses were then placed in vials with 1.5 mL of artificial tear solution containing 125I-labeled albumin for 16 hours at 37°C with shaking. Four uncoated lenses of each type were used as controls. Lenses soaked in radiolabeled albumin were rinsed in a phosphate-buffered saline solution, and radioactive counts were measured directly on lenses using a gamma counter. Albumin uptake on lenses was measured using a calibration curve by plotting radioactive counts versus protein concentration. RESULTS: Results are reported as mean ± SD. Lysozyme-coated etafilcon A lenses exhibited lower levels of deposited albumin than uncoated etafilcon A lenses (58 ± 12 vs. 84 ± 5 ng/lens; P .05). Uncoated nesofilcon A lenses deposited the highest amount of albumin when compared with other uncoated lenses (P <.05). CONCLUSIONS: This study demonstrates that lysozyme deposited onto etafilcon A resists the deposition of albumin, which may potentially be beneficial to CL wearers. Copyright © 2017 American Academy of Optometry.

Omali,N. B., Subbaraman,L. N., Heynen,M., Lada,M., Canavan,K., Fadli,Z., Ngo,W., Jones,L. Lipid deposition on contact lenses in symptomatic and asymptomatic contact lens wearers Cont Lens Anterior Eye 2021;44(1):56-61 [ Show Abstract ]

Purpose
Lipid deposition on contact lenses (CL) has traditionally been believed to reduce comfort during CL wear. The purpose of this study was to quantify lipid deposition on CL in a group of symptomatic and asymptomatic adapted CL wearers.

Methods
This was a single-masked, randomized clinical trial. Only confirmed symptomatic (comfortable lens wear time (CWT) 10 h and minimal reduction in comfort over the course of the day) participants were recruited to participate in the study. Participants wore senofilcon A lenses in combination with a polyquaternium-based care solution (OPTI-FREE Replenish). Worn CL samples were collected on Day 14. Deposited lipid amounts from the lenses (including cholesteryl ester, cholesterol and triolein) were quantified using a liquid chromatography-mass spectrometry technique.

Results
Lipid deposition was significantly higher in CL extracts of asymptomatic wearers compared to the symptomatic wearers for all lipid types quantified, including cholesteryl ester (2.1 ± 0.6 vs 1.6 ± 0.5 log μg/lens), cholesterol (1.5 ± 0.3 vs 1.1 ± 0.3 log μg/lens) and triolein (0.3 ± 0.2 vs 0.1 ± 0.1 log μg/lens) (all p < 0.002). The amount of cholesteryl ester deposited was greatest (p = 0.0001), followed by cholesterol, then triolein, for both the asymptomatic and symptomatic groups (both p = 0.0001).

Conclusion
This study demonstrated that the asymptomatic group deposited a significantly greater amount of lipid on their CL. Although lipid levels measured are considered low to trigger any observable clinical deposition, they may influence other clinical outcomes, particularly comfort.

Omali,N.B., Subbaraman,L.N., Heynen,M., Ng,A., Coles-Brennan,C., Fadli,Z., Jones,L. Surface versus bulk activity of lysozyme deposited on hydrogel contact lens materials in vitro Contact Lens and Anterior Eye 2018;41(4):329-334 [ Show Abstract ]

Purpose: To determine and compare the levels of surface versus bulk active lysozyme deposited on several commercially available hydrogel contact lens materials. Methods: Hydrogel contact lens materials [polymacon, omafilcon A, nelfilcon A, nesofilcon A, ocufilcon and etafilcon A with polyvinylpyrrolidone (PVP)] were incubated in an artificial tear solution for 16 h. Total activity was determined using a standard turbidity assay. The surface activity of the deposited lysozyme was determined using a modified turbidity assay. The amount of active lysozyme present within the bulk of the lens material was calculated by determining the difference between the total and surface active lysozyme. Results: The etafilcon A materials showed the highest amount of total lysozyme activity (519 ± 8 μg/lens, average of Moist and Define), followed by the ocufilcon material (200 ± 5 μg/lens) and these two were significantly different from each other (p < 0.05). The amount of surface active lysozyme on etafilcon and ocufilcon lens materials was significantly higher than that found on all other lenses (p < 0.05). There was no active lysozyme quantified in the bulk of the nelfilcon material, as all of the active lysozyme was found on the surface (1.7 ± 0.3 μg/lens). In contrast, no active lysozyme was quantified on the surface of polymacon, with all of the active lysozyme found in the bulk of the lens material (0.6 ± 0.6 μg/lens). Conclusions: The surface and bulk activity of lysozyme deposited on contact lenses is material dependent. Lysozyme deposited on ionic, high water content lens materials such as etafilcon A show significantly higher surface and bulk activity than many other hydrogel lens materials.

Osae,E. A., Jones,L., Nichols,J. J. The impact of contact lenses on meibomian gland morphology Ocular Surface 2022;24(April):148-155 [ Show Abstract ]

Despite years of experience with contact lenses, controversy remains as to whether contact lenses adversely impact the meibomian glands (MG). This review summarizes the present body of evidence, showing that contact lens wear is associated with alterations in MG morphology (up to 80% higher gland atrophy compared to non-wearers) and qualitative changes in MG secretion. Key factors such as duration of contact lens wear, contact lens type (e.g., soft vs. rigid), edge design, and material modulus of elasticity are discussed in relation to the extent of MG morphological changes, the quality of MG secretion and other ocular surface parameters. Longitudinal studies of sufficient statistical power are needed to better understand how contact lens wear affects the MG, risk factors, and the clinical sequelae of these changes.

Otchere,H., Jones,L. W., Sorbara,L. Effect of Time on Scleral Lens Settling and Change in Corneal Clearance Optometry and Vision Science 2017;94(9):908-913 [ Show Abstract ]

SIGNIFICANCE With the increase in the use of scleral contact lenses among practitioners, questions regarding lens settling are gradually gaining attention. This is because current studies support the notion that scleral lenses settle back over time. More research is needed to understand the exact cause and the factors that underpin such phenomenon. PURPOSE The present study aims to assess the effect of time on topographic corneal clearance of three scleral contact lenses of varying sagittal depths. METHODS Three scleral contact lenses were fitted to 20 subjects with previous diagnosis of keratoconus (n = 18) or pellucid marginal degeneration (n = 2). The fit was based on corneal sagittal height measured with the Visante optical coherence tomographer (OCT) at 15 mm along the horizontal meridian. To select an appropriate lens from the diagnostic lens set, values of 325 μm (lens 1), 375 μm (lens 2), and 425 μm (lens 3) were randomly added in sequence to the corneal sagittal height. Subjects wore each lens for 1 hour. Corneal clearance was measured at 10-minute intervals for 1 hour using a custom ultra-long OCT. To assess change in clearance, central point and two mid-peripheral points (+3 mm and -3 mm) along an 8-mm chord were measured by taking differences at each time point up to 1 hour. Measurements were repeated for the two other lenses. RESULTS Mean central corneal clearance loss for all three lenses was 33.83 ± 48.40 μm. This was 26 ± 27 μm (13 ± 14 μm, +3 mm; 34 ± 37 μm, -3 mm), lens 1; 35 ± 59 μm (38 ± 61 μm, +3 mm; 52 ± 69 μm, -3 mm), lens 2; and 41 ± 54 μm (33 ± 26 μm, +3 mm; 52 ± 48 μm, -3 mm), lens 3, respectively. There was no significant difference (P = 0.06) at central and other locations for lens 1 (location and over time). There were significant differences for both lenses 2 and 3 (P <.001, P =.01, respectively) for all three locations and over time. CONCLUSIONS There is a likelihood of clearance loss after 1 hour of lens wear. This varies between subjects, initial lens-fit relationship, and over time.