Publications

Showing 25 results out of 93 in total.

Luensmann,D., Omali,N. B., Suko,A., Drolle,E., Heynen,M., Subbaraman,L. S., Scales,C., Fadli,Z., Jones,L. Kinetic Deposition of Polar and Non-polar Lipids on Silicone Hydrogel Contact Lenses Current Eye Research 2020;45(12):1477-1483 [ Show Abstract ]

Purpose: This study investigated kinetic lipid uptake to four silicone hydrogel (SiHy) lenses over a period of four weeks, using an in-vitro radiolabel method.

Methods: Four contemporary monthly replacement SiHy lenses (lotrafilcon B, senofilcon C, comfilcon A, samfilcon A) were incubated in three different solutions: 1) An artificial tear solution (ATS) containing 14C-labeled phosphatidylcholine (PC), 2) an ATS containing 14C-cholesteryl oleate (CO) and 3) an ATS containing four 14C-radiolabeled lipids (PC, phosphatidylethanolamine, CO, and cholesterol (total lipid)). After 16 hours, lipids were extracted twice from the lenses with chloroform:methanol and the radioactive counts determined the lipid quantities to simulate 1 day of wear. OPTI-FREE PureMoist (Alcon) was used to clean and disinfect the remaining lenses daily and the lipid quantities were further determined after 2 weeks and 4 weeks.

Results: The amount of total lipid increased for all lenses over time (p < .01). After four weeks, total lipid accumulated was 20.26 ± 0.15 µg/lens for senofilcon C, which was significantly higher (p < .01) than all other lens materials (samfilcon A - 17.84 ± 0.21; comfilcon A - 16.65 ± 0.12; lotrafilcon B - 7.41 ± 0.56 µg/lens). CO was highest on lotrafilcon B (1.26 ± 0.13 µg/lens) and senofilcon C attracted the most PC (3.95 ± 0.12 µg/lens) compared to the other materials.

Conclusion: The amount of both polar and non-polar lipid deposition on monthly replacement SiHy lenses increased over 4 weeks, with significant differences being seen between lens materials.

Luensmann,D., van Doorn,K., May,C., Srinivasan,S., Jones,L. The Impact of Cosmetics on the Physical Dimension and Optical Performance of Contemporary Silicone Hydrogel Contact Lenses Eye & Contact Lens 2020;46(3):166-173 [ Show Abstract ]

Purpose: Contact lens wearers may inadvertently expose their lenses during the lens insertion and removal process or while wearing their lenses to cosmetic products being used. This study investigated the impact of
various cosmetics on the physical dimension and optical properties of three recently marketed monthly replacement silicone hydrogel contact lenses.

Methods: In this in vitro study, three monthly replacement silicone hydrogel lens types including senofilcon C (ACUVUE VITA, Johnson & Johnson), samfilcon A (Bausch+Lomb ULTRA, Bausch+Lomb), and lotrafilcon
B+EOBO (polyoxyethylene-polyoxybutylene) (AIR OPTIX plus HydraGlyde, ALCON), were individually coated with cosmetic products followed by a 1-hr soak in phosphate-buffered saline. Cosmetic products
included; three hand creams (HC1: Glysomed; HC2: Vaseline Healthy Hand & Nail Conditioning; and HC3: Intense Relieve), three make-up removers (MR1: Lid-Care Towelettes; MR2: Gentle waterproof eye and
Lip Makeup Remover; and MR3: Oil-Free Makeup Remover), and three mascaras (MA1: Great Lash—waterproof; MA2a: Wonder’Lash—waterproof, and MA3: Voluminous Original). The contact lens dimensions were
determined for diameter, sagittal depth, and base curve, using the Chiltern (Optimec Limited), whereas lens power and optical quality were assessed using the Contest Plus II (Rotlex). Six replicates for each lens/cosmetic combination were used. The impact of cosmetics was tested between lenses and compared with uncoated control lenses.

Results: For lens diameter, makeup removers (MR2 & MR3) demonstrated the largest impact, with an increase of up to 0.26 mm (MR2) and 0.35 mm (MR3) for senofilcon C and samfilcon A, respectively (P,0.01 compared to baseline), whereas lotrafilcon B+EOBO showed a decrease of 0.01 mm (P,0.01 between lens types). For sagittal depth, mascara MA1 demonstrated the greatest impact, followed by makeup removers MR2 & MR3. All lenses showed increases in sagittal depth after MA1 exposure (0.1660.06 mm in lotrafilcon B+EOBO, 0.2460.22, and 0.2660.09 mm in samfilcon A and senofilcon C, respectively; P,0.01 for all lenses compared with baseline). For base curve, the makeup removers (MR2 & MR3) caused increases for both senofilcon C (up to 0.36 mm) and samfilcon A (up to 0.35 mm), but lotrafilcon B+EOBO was unaffected. Lens power changes were generally minor (,0.25 D). However, senofilcon C showed a significant change of 21.1860.65 D (more minus) after MA1 exposure (P,0.001). Image quality was most affected by mascaras, although given that all lens types were adversely affected to similar degrees, none of the lenses performed better or worse after mascara application (P.0.05). The parameters of the different lens types were not significantly affected by the hand creams.

Conclusion: Makeup removers and mascaras changed the lens parameters to varying degrees, which may affect the fit and overall performance of the lens, whereas no such effect was noted with hand creams. Lotrafilcon B+EOBO was typically less affected compared with senofilcon C or samfilcon A.

Luensmann D, Schulze M, Ng AY, Woods J, Jones L. Refitting symptomatic daily disposable contact lens wearers with dry eye disease with delefilcon A lenses Academy at Home, 2020 [ Show Abstract ]

Purpose: To refit symptomatic wearers of daily disposable (DD) contact lenses with a confirmed dry eye diagnosis with Dailies Total1 (delefilcon A, Alcon) to evaluate the performance of the new lenses after one month of wear.
Methods: In this prospective, participant-masked study (over-labelled lenses), symptomatic DD lens wearers were recruited who demonstrated symptoms and signs of dry eye disease according to the TFOS DEWS II criteria. The performance of the lenses after one month was evaluated using subjective ratings and comfort scores, and by determining average wear time and comfortable wear time. Lens wear times as well as subjective symptom scores for comfort, dryness and vision (0-100 scale, with 100 being best) with habitual DD were collected at the screening visit and these results were then compared to delefilcon A after 1 month of wear. The data were not normally distributed, therefore non-parametric analysis (Wilcoxon Matched Pairs Test) was conducted. Data are reported as median (range), with delefilcon A data reported first.
Results: In total, 27 symptomatic DD lens wearers (19 female, 8 male) completed the study. Comfort ratings across all participants were significantly higher (p=0.014) for delefilcon A (80 (40-100)) compared to habitual DD lenses (80 (25-90)). Participants reported less dryness (p=0.007) with delefilcon A compared to their own lenses (80 (40-100) vs 70 (20-95)), and no difference in vision (p>0.05, 90 (50-100) vs (85 (60-100)). There were no statistically significant differences in total hours of lens wear per day (p>0.05, 12.5 hours (6.5-17) vs 11 hours (2.5-16)) or for comfortable wearing time (p>0.05, 8 hours (1-17) vs 6 hours (1-14.8). There were no lens-related ocular findings after one month of delefilcon A wear.
Conclusion: In general, participants had a positive lens wear experience with delefilcon A and rated this lens more comfortable and less dry compared to their habitual DD lenses. This suggests that symptomatic DD lens wearers with dry eye disease may benefit when refit into delefilcon A lenses.

Luensmann D, Woods J, McParland M.. Toric lens fitting success supported by an online fitting App Contact Lens Anterior Eye 2020 [ Show Abstract ][ PDF ]

Purpose: To provide eye care professionals quick access to lens parameter availability and to make soft toric lens fitting easier, online tools are now available to calculate and suggest a first choice prescription based on the patient’s subjective refraction. How close the recommended prescription matches the dispensed lens has been investigated in this study.

Method: In clinical studies, two daily disposable toric lenses, stenfilcon A and somofilcon A, and one monthly replacement toric lens, comfilcon A (all CooperVision, Inc.), were fitted and dispensed to 54, 37 and 47 habitual lens wearers respectively, following the manufacturer’s fitting guides. The final lens prescriptions were determined by the clinician based on over-refraction and lens rotation (Final-Rx). In a secondary analysis the subjective refraction data and back vertex distance were entered in the OptiExpert™ app to determine the recommended initial trial lens (App-Rx). The prescription results from both approaches were compared by calculating the mean differences (Bland-Altman) and the percentages of matching prescriptions following predetermined allowances for sphere, cylinder and axis.

Results: The mean differences between OptiExpert™ and the clinician final prescriptions for sphere, cylinder and axis were within ±0.13DS, ±0.01DC and ±1.38 degrees, respectively. For allowance combination sphere ±0.25D, cylinder ±0.00DC, axis ±10 degrees, the lens prescriptions from both methods matched in 75-82% of eyes (82% stenfilcon A, 75% somofilcon A, 79% comfilcon A). For allowance combination of sph ±0.50D, cyl ±0.00DC, axis ±20 degrees the Final-Rx and the App-Rx matched in 86-92% of eyes (91% stenfilcon A, 92% somofilcon A, 86% comfilcon A).

Conclusions: All three toric lens types showed a predictable on-eye performance, resulting in a close agreement between the initial OptiExpert recommended prescription and the lens prescription dispensed by the clinician. The OptiExpert™ app can therefore confidently be used to assist CooperVision toric lens fitting in order to help optimize patient chair time.

Luensmann D, Woods J, McParland M.. The use of a modern web-application to assist reusable toric lens fitting success Contact Lens Anterior Eye 2020 [ Show Abstract ][ PDF ]

Purpose: Increasing numbers of online tools are available to assist ECPs in fitting contact lenses. In this study, the contact lens prescription of a reusable toric silicone hydrogel lens was determined using a traditional fitting guide and the results were compared to the prescription recommended by the lens fitting app OptiExpert™.

Method: Forty-seven habitual lens wearers were fit with monthly replacement toric silicone hydrogel contact lenses (comfilcon A; CooperVision, Inc.).The manufacturer’s fitting guide was followed and the final lens prescription was determined based on the subjective refraction, the over-refraction and lens rotation (Final-Rx). Following this clinical study, the participant’s subjective refraction data and back vertex distance were entered in the OptiExpert online app to determine the recommended initial trial lens prescription (App-Rx). In this secondary analysis, the fitting results from both approaches were compared using Pearson correlation analysis. Different allowances for sph (±0.25, ±0.50D), cyl (±0.00DC) and axis (±10, ±20degrees) were combined to calculate the percentage of matching fitting results between both methods. Additionally, Bland-Altman graphs were plotted.

Results: A high correlation was found in respect to sphere, cylinder and axis between the Final-Rx and the App-Rx (all r ≥0.88). For the allowance combination of sphere ±0.25D / cylinder ±0.00DC / axis ±10, the lens prescriptions from both methods matched in 79% of eyes. For the allowance combination of sphere ±0.50D / cylinder ±0.00DC / axis ±20, the Final-Rx and the App-Rx matched in 86% of eyes. Bland-Altman comparisons between methods determined a mean difference of +0.06D for sph, +0.01D for cyl and 1.38 degrees for axis.

Conclusions: For most participants, the initial trial lens power recommended by the OptiExpert app was in close agreement to the final power dispensed in the clinical setting. The OptiExpert app can confidently be used as a clinical tool to aid comfilcon A toric lens fitting success.

Morgan P, Jones L, Gifford K.. Orthokeratology for myopia control in Covid-19 era Optician 2020, August: 12-14 [ Show Abstract ]

The year 2020 was affectionately termed ‘the year of optometry’ but the new decade has brought numerous challenges to the profession as the ongoing Covid-19 pandemic has seen normal clinical practice greatly disrupted. As the lockdown begins to ease, many aspects of normal optometric and optical functions are being reconsidered.

Due to their application to the ocular surface, the use of contact lenses has faced particular scrutiny and some media reports have advocated the cessation of contact lens use despite the absence of clear evidence for an increased risk of Covid-19 infection or any increase of eye touching during lens wear. Indeed, a recent review of the literature found no relationship between lens use and Covid-19 infection 1 and a separate report indicated that coronaviruses such as SARS-CoV-2 (the virus which causes Covid-19) are unlikely to bind to ocular surface cells to initiate infection.2 Related to this, although there are a number of reports of conjunctivitis occurring prior to symptoms of Covid-19, 3,4 a United Kingdom report of over 20,000 hospital patients with the disease found that only 0.3% presented with conjunctivitis. 5 Although more work is required to fully understand this area and new information is becoming available daily, it appears that the ocular surface is not a major point of ingress for the virus 6 and overall, contact lens wear continues to be safe.

Professional bodies and regulatory agencies including the College of Optometrists, 7 the British Contact Lens Association8 and the United States Centers for Disease Control and Prevention 9 concur that there is no association between contact lens use and Covid-19 infection. However, all these groups stress the need for hygienic contact lens use at this time, a recommendation which in part may relate to the need to minimise the requirement for contact lens wearers to seek clinical advice at a time where optometric services may not be fully operational and other healthcare facilities are also offering a reduced service. Furthermore, contact lens wearers should ideally refrain from attending emergency departments where they may be exposed to the virus.

Morgan P, Woods CA, Tranoudis IG, Efron N, Jones L, Merchan B, Grupcheva CN, Jones D, Beeler-Kaupke M, Krasnanska J, Belova S, Ravn O, Santodomingo-Rubido J, Taste P, Malet F, Plakitsi A, Végh M, Erdinest N, Montani G, Itoi M, Bendoriene J, Ramos Gómez RL, Pintor R, Mulder J, Van Der Worp E, Lam W, Ystenæs AE, Romualdez-Oo J, Abesamis-Dichoso C, González-Méijome J, Gierow P, Pettersson LA, Hsiao J, Nichols JJ . International Contact Lens Prescribing in 2019 Contact Lens Spectrum 2020;35, January: 26-32 [ Show Abstract ]

Since the turn of the century, we have presented annual overviews of contact lens prescribing trends in Contact Lens Spectrum. The work was initiated to help eyecare practitioners who are active in contact lenses to benchmark their fitting habits against their peers as well as to provide context to researchers in the field working on next-generation products. The database of lens fits collected over this period now exceeds 400,000, and the information has been collected across 71 markets.

In each targeted market, we supply survey forms and request that practitioners complete generic information about the first 10 contact lens fits conducted after receipt. This fundamental approach has remained unchanged since the first survey was conducted in the United Kingdom in 1996, with only minor changes to the form to account for new products becoming available on the market. For example, an option for “anti-myopia” (now termed “myopia control”) lenses was introduced in the 2011 survey to allow us to track developments in that area.

The distribution of the survey form varies. Some markets continue to use paper forms with a reply-paid envelope; others distribute and collect the same form via e-mail or a web-based questionnaire. The work is coordinated in each market by national coordinators who are listed as co-authors of this paper.

The survey forms request information about the age and sex of each contact lens patient fitted in addition to data about the material, design, replacement frequency, and wearing modality of the fitted lenses; anticipated weekly usage; and care system type. Each fit is weighted based on the estimated annualized number of fits for each practitioner. The data are finally collated at both the University of Manchester in the United Kingdom and at the University of Waterloo in Canada.

Muntz,A., Subbaraman,L.N., Craig,J. P., Jones,L. Cytomorphological assessment of the lid margin in relation to symptoms, contact lens wear and lid wiper epitheliopathy Ocular Surface 2020;18(2):214-220 [ Show Abstract ]

Purpose: Lid wiper epitheliopathy (LWE) is insufficiently understood from a cytological perspective. This study explored the relationship between lid margin cytomorphology, LWE, contact lens wear, and lens-related symptoms. Methods: Habitual, symptomatic (n = 20) and asymptomatic (n = 20) soft, rigid gas permeable (n = 18) and non-contact lens wearers (n = 19) were enrolled. LWE was graded using lissamine green and the Korb scale. Subjective symptoms were assessed using the Ocular Surface Disease Index and the Contact Lens Dryness Evaluation Questionnaire. Impression cytology samples obtained from the central upper and lower lid margins of both eyes stained histologically to highlight keratinization and imaged using high-resolution microscopy. A masked investigator digitally delimited and measured the average sagittal width of the lid wiper conjunctiva and mucocutaneous junction using ImageJ. Results: The upper lid wiper conjunctiva measured 424 ± 171 μm, 404 ± 75, 667 ± 219 and 266 ± 64 in asymptomatic soft, symptomatic soft, rigid and non-contact lens wearers, respectively. The corresponding lower lid wiper conjunctivae measured 141 ± 57 μm, 232 ± 150, 519 ± 212 and 225 ± 102, which was significantly narrower than that of the upper eyelid in most cases (p < 0.05). Symptoms were not associated with lid margin changes; however, rigid lens wear and clinical LWE were associated with histologically enlarged lid wiper conjunctival areas and increased keratinization. Conclusion: A novel, exploratory account of histological measures of LWE and cytomorphological change associated with contact lens wear suggests mechanical or frictional cellular insult is occurring at the lid wiper conjunctiva.

Nagaarudkumaran N, McCanna D, Ngo W, Jones L. In vitro quantification of cytokines adhered to contemporary contact lens materials The Association for Research in Vision and Ophthalmology, 2020 [ Show Abstract ][ PDF ]

Purpose : Contact lenses (CL) may induce a low-level inflammatory response on the ocular surface. Previous studies have quantified the concentration of inflammatory mediators present in the tear film during CL wear. Analyzing the inflammatory mediators loosely adhered to CL materials may provide another perspective on the role that contact lenses play in inflammation. The purpose of this in vitro study was to quantify a variety of cytokines found in the tear film that adhered to various CL materials and to develop a method that could extract them.

Methods : Cytokines IL-1β, IL-6, IL-8, and TNF-α (Meso Scale Diagnostics, Rockville, MD) were combined with 5 mL of Diluent 2 to prepare a cytokine solution with a final concentration of 119.41, 166.05, 101.48 and 40.73 pg/mL, respectively. Contact lenses (etafilcon A, somofilcon A, omafilcon A, delefilcon A) (n=4 each) were each placed into a polypropylene tube containing a volume of 200 μL of the prepared cytokine solution and were incubated at 23°C for 6 hours. The lenses were removed from the tubes using tweezers and placed into a 0.6 mL microcentrifuge tube containing 200 μL of Diluent 2 and were incubated at 23°C for 1 hour. The microcentrifuge tube was then vortexed for 5 seconds and pin sized holes were made at the base of the tube. The tube was then placed into a larger 2.0 mL microcentrifuge tube acting as a carrier and were centrifuged at 604 RCF. The eluent in the 2.0 mL microcentrifuge was then collected and stored at -80°C for cytokine quantification at a later date, using the MESO QuickPlex SQ 120 (Meso Scale Diagnostics, Rockville, MD). Statistical analysis was performed using a one-way ANOVA.

Results : There was no significant difference between cytokine concentrations for all CL materials (p>0.05).

Conclusions : While there were no significant differences between the concentrations of cytokines found loosely adhered to the soft CL materials investigated, the results support this method as a means to quantify such cytokines on soft lens materials. This method may be used to examine human-worn lenses in future studies.

This is a 2020 ARVO Annual Meeting abstract.

Nichols,J. J., Jones,L., Morgan,P. B., Efron,N. Bibliometric analysis of the orthokeratology literature Contact Lens Anterior Eye 2020;Article in Press [ 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.

Phan CM, Shukla M, Heynen M, Walther H, Jones L. Development of an In Vitro Blink Model for Measuring Drug and Comfort Agent Elutes from Soft Contact Lens Polymers Academy at Home, 2020 [ Show Abstract ]

Purpose: To develop an advanced in vitro blink model that could be used to examine release of a wide variety of components (topical drugs; comfort agents etc) from soft contact lenses.
Methods: The model was designed using CAD software and 3D printed using an SLA printer. A UV-curable resin polymer was used to fabricate the main components of the eye model to ensure water-sealed parts. The eyelid and eyeball were synthesized from a polyvinyl alcohol and a silicone material respectively. Simulated tear fluid is delivered through tubing attached to the eyelid. With each blink cycle (1 blink/10s), the eyelid slides and flexes across the eyeball to create an artificial tear film. The flow-through fluid is collected in a specialized trough. Two contact lenses, etafilcon A and senofilcon A, were incubated in 2 mL of a water-soluble red dye for 24 hours and then placed on the eye model. The release of the dye was measured at t= 0.5, 1, 2, 4, 8, 12, and 24 hours (n=3) in phosphate buffered saline (flow rate = 5 µL/min). The dye release from the lenses was also evaluated in a vial containing 2 mL of PBS over 24 hours (n=3). The amount of dye in the samples was determined using a UV/Vis spectrophotometer at 520 nm.
Results: All of the contact lenses were visibly red after the incubation with the dye. After the release studies, the etafilcon A lenses became transparent with a slight red tint, whereas the senofilcon A lenses retained a moderate red colour. For the vial study, the release of the dye from the contact lenses was rapid within the first 4 hours, which was then followed by a slower release phase. In contrast, dye release from the lenses on the eye model was significantly slower and was sustained over the 24-hour period. The total amounts of dye released in the eye model were also significantly lower compared to the vial (p<0.05), which could be attributed to the absorption of the dye into the eyelid. From the total amount of tear fluid (7.2 mL) that was infused into the eye model, approximately 5.2 ± 0.6 mL of flow-through was collected. The loss of fluid can be attributed to fluid absorption into the eyelid and contact lenses, as well as evaporation.
Conclusion: The blink model developed in this study could be used to measure the release of topical ophthalmic drugs or comfort agents from contact lenses. The results showed that the release kinetics of a dye from contact lenses on the eye model was significantly different than that of a vial. The model also simulated non-specific absorption of the dye into the eyelid. Future work will focus on developing polymers to simulate the absorption of drugs on the eye.

Qiao,H., Luensmann,D., Heynen,M., Drolle,E., Subbaraman,L. N., Scales,C., Riederer,D., Fadli,Z., Jones,L. In Vitro Evaluation of the Location of Cholesteryl Ester Deposits on Monthly Replacement Silicone Hydrogel Contact Lens Materials Clinical Ophthalmology 2020;142821-2828 [ Show Abstract ]

Purpose: The deposition profile of cholesteryl ester on the surface and throughout the matrix of silicone hydrogel contact lens (CL) materials was determined under conditions that mimic a daily wear regimen.

Methods: In this in vitro study, four SiHy CL materials (senofilcon C, lotrafilcon B, comfilcon A and samfilcon A) were incubated in an artificial tear solution (ATS) for up to 30 days. CL incubation was alternated between the ATS (16 hours) and a multipurpose care regimen (8 hours). The ATS included fluorescently tagged cholesteryl ester (5-cholesten-3ß-ol 6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]caproate; CE-NBD) and confocal laser scanning microscopy visualized the distribution of the lipid through the CLs.

Results: The distribution of CE-NBD was homogenous from the anterior to posterior surface in senofilcon C and comfilcon A, at all time points. For lotrafilcon B and samfilcon A, CE-NBD localization was heterogeneous, with greater amounts on the surfaces on Day 1 and Day 14 compared to the lens matrix; however, differences in concentration between the surface and bulk diminished by Day 30.

Conclusion: The distribution of the non-polar lipid CE-NBD varied with lens material chemistry. While some lens materials deposited the lipid primarily on the surface after 16 hours of exposure, all materials exhibited a homogenous distribution after one month.

Keywords: lipid distribution, silicone hydrogel contact lenses, cholesteryl ester, artificial tear solution

Rangarajan,R., Ketelson,H. A., Do,R., McCanna,D. J., Suko,A., Enstone,D., Subbaraman,L., Dantam,J., Jones,L. W. Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation Journal of Visualized Experiments 2020 (159):e60812 [ Show Abstract ]

Artificial lipid-containing tear formulations are developed to reduce tear evaporation by the restoration of a deficient tear lipid layer. Artificial tear formulations that prevent cell desiccation will result in ocular surface protection and the maintenance of cell metabolic activity. During dehydration, cells undergo the process of loss of metabolic activity and subsequently cell death. This work describes a method for assessing the efficacy of artificial tear formulations. The metabolic dye (i.e., alamarBlue) changes from a low fluorescent molecule resazurin to a fluorescent molecule resorufin in viable cells. The biological performance of an artificial tear formulation is measured as the ability of the formulation to (a) maintain cell viability and (b) provide cell protection from desiccation. Growth media and saline are used as controls for the cell viability/desiccation tests. Cells are incubated with test solutions for 30 min and then desiccated for 0 or 5 min at 37 °C and 45% relative humidity. Cell metabolic activity after initial exposure and after cell desiccation is then determined. The results show the comparative effects of eye drop formulations on cell metabolic activity and desiccation protection. This method can be used to test dry eye formulations that are designed to treat individuals with evaporative dry eye.

Schulze M. Blink Mechanics: Why it Matters Review of Cornea and Contact Lenses 2020;January/February

Schulze M, Ng AY, Luensmann D, Guthrie S, Woods J, Jones L. The subjective response to verofilcon A daily disposable contact lenses during extensive digital device use Academy at Home, 2020 [ Show Abstract ]

Purpose: To evaluate the subjective response of habitual lens wearers during extensive digital device use when switched to Precision1 (verofilcon A) daily disposable (DD) contact lenses (CLs).
Methods: Volunteers between 18-40 years of age who used digital devices for at least 6 hours/day while wearing their habitual CLs were recruited for the study. Eligible participants were dispensed with verofilcon A DD CLs for a period of 2 weeks, during which they were required to wear the study CLs for at least 5 days/week and at least 10 hours/day. Participants returned after 142 days for their final visit, where they reported their CL wear time and time spent using digital devices, and rated their typical experience on a 0 to 100 scale, with 100 being best. Comfort, dryness and clarity of vision with verofilcon A were rated directly after insertion, after 6 hours of digital device use, and just before removal, as well as by rating their overall performance. Participants also completed a 4-point (strongly agree, slightly agree, slightly disagree, strongly disagree) Likert scale-based questionnaire. Subjective ratings were not normally distributed, therefore non-parametric analysis was conducted and data are reported as median (range). The Likert scale responses were analyzed using binomial testing.
Results: Twenty participants completed the study (18F:2M), mean age of 25.1 ± 6.0 years (range 19-40). They reported their typical day to include median CL wear time of 13.8 hours (10.5-17), comfortable CL wear time of 12.1 hours (8-16.5) and digital device use of 9 hours (6-12). After 2 weeks of verofilcon A DD CL wear, subjective ratings after 6 hours of digital device use were high, with ratings for a typical day of 93 (68-100) for comfort, 93 (52-100) for dryness and 96 (70-100) for clarity of vision. After 2 weeks of wear, the majority of participants agreed that the study lenses provided good comfort (16/20 subjects; p=0.01) and good vision (18/20; p<0.01) all day long. Similarly, the majority of participants were satisfied with the comfort (16/20; p=0.01), vision (18/20; p<0.01) and overall performance (16/20; p=0.01) they experienced with the study lenses while using digital devices for 6 hours. Additionally, most reported they did not experience any eye strain while using verofilcon A lenses (n=16/20; p=0.01). No significant lens-related ocular findings were observed after 2 weeks of wear.
Conclusions: After 2 weeks of wear, participants rated the performance of verofilcon A DD CLs very highly, with median overall performance ratings for comfort, dryness and vision all 93 on the 0 to 100 scale (with 100 being best). Verofilcon A DD CLs may be a viable alternative for those struggling with their habitual lens performance when spending long hours using digital devices.

Shows,A., Redfern,R. L., Sickenberger,W., Fogt,J. S., Schulze,M., Lievens,C., Szcottka-Flynn,L., Schwarz,S., Tichenor,A. A., Marx,S., Lemp-Hull,J. M. Lipid Analysis on Block Copolymer–containing Packaging Solution and Lens Care Regimens: A Randomized Clinical Trial Optometry & Vision Science 2020;97(8):565-572 [ Show Abstract ]

SIGNIFICANCE: Lotrafilcon B lenses packaged in and cared for with block copolymer–containing (polyoxyethylenepolyoxybutylene; EOBO) lens care solutions resulted in lower cholesterol extraction than each of the habitual silicone hydrogel lens/multipurpose solution (MPS) regimens tested.

PURPOSE: This study aimed to compare the extracted cholesterol of lotrafilcon B lenses packaged in and cared for with EOBO-containing lens care solutions with the extracted cholesterol of habitual silicone hydrogel lenses cared for with MPS not containing EOBO.

METHODS: In this prospective, randomized, observer-masked parallel study, habitual wearers of senofilcon C, senofilcon A, comfilcon A, and samfilcon A contact lenses using a non-EOBO MPS were randomized 1:1 to lotrafilcon B lenses packaged in and cared for with EOBO-containing solutions or to their habitual lenses and MPS. Subjects randomized to lotrafilcon B were further randomized to one of two EOBO-containing lens care solutions, OPTI-FREE PUREMOIST or CLEAR CARE PLUS with HydraGlyde (Alcon Laboratories, Inc., Fort Worth, TX). A subset of right eye lenses was collected after wear, and total cholesterol was extracted and measured using a fluorometric enzymatic assay.

RESULTS: Of 143 lenses analyzed, 95 were from subjects randomized to their habitual lenses/MPS and 48 to lotrafilcon B + EOBO lenses plus CLEAR CARE PLUS with HydraGlyde or OPTI-FREE PUREMOIST. The mean amounts of cholesterol extracted from lotrafilcon B + EOBO lenses cared for with CLEAR CARE PLUS with HydraGlyde (0.28 ± 0.18 μ g/lens) and OPTI-FREE PUREMOIST (0.28 ± 0.48 μ g/lens) were significantly lower than those extracted from senofilcon C (4.18 ± 3.25 μ g/lens), senofilcon A (2.19 ± 2.69 μ g/lens), comfilcon A (2.17 ± 1.47 μ g/lens), and samfilcon A (2.07 ± 1.48 μ g/lens) lenses used with MPS (P < .0001 each).

CONCLUSIONS: Cholesterol sorption was significantly lower in wearers of lotrafilcon B lenses cared for with polyoxyethylene-polyoxybutylene–containing lens care solutions than in users of habitual silicone hydrogel lenses cared for with non–polyoxyethylene-polyoxybutylene MPS.

Silverstein,S., Yeu,E., Tauber,J., Guillon,M., Jones,L., Galarreta,D., Srinivasan,S., Manoj,V. Symptom Relief Following a Single Dose of Propylene Glycol-Hydroxypropyl Guar Nanoemulsion in Patients with Dry Eye Disease: A Phase IV, Multicenter Trial Clinical Ophthalmology 2020;14(October):3167-3177 [ Show Abstract ]

Purpose: To evaluate symptom relief in patients with dry eye disease (DED) following a single drop of propylene glycol-hydroxypropyl guar (PG-HPG) nanoemulsion (Systane® Complete) lubricant eye drops.

Methods: This was a Phase IV, multicenter, open-label, interventional study in adult patients with DED of aqueous-deficient, evaporative, and mixed subtypes. Patients instilled one drop of PG-HPG in each eye at Day 1. Endpoints included change from baseline in dry eye symptom and soothing sensation scores on Day 1 at 0, 4, and 8 hours post-dose. Symptom scores were assessed on a 0– 10 scale (0=no symptoms; 10=worst imaginable symptom). Tolerability of the drop was assessed based on assessment score on Day 1 following instillation for overall cohort and by DED subtype.

Results: A total of 134 patients received treatment (mean age: 56.6 years; female: 75.4%). Median changes from baseline at Day 1 in dry eye symptom scores were − 1.0 (95% confidence interval [CI]:-3.0,-1.0), − 2.0 (95% CI:-3.0,-2.0), and − 2.0 (95% CI:-2.0,-1.0) at 0, 4, and 8 hours respectively. Subgroup analysis showed a median change from baseline in dry eye symptom score of − 2 (95% CI:-3.0,-1.0) for aqueous-deficient and evaporative subtypes and − 1 (95% CI:-3.0,-1.0) for mixed subtype at 8 hours. Median soothing sensation scores were 3 at 0 and 4 hours and 3.5 at 8 hours, with a range of 0– 10. Median (range) tolerability assessment scores were 0 (0– 8) for burning sensation, stinging sensation, blurring, and 0 (0– 10) for foreign body sensation. Tolerability assessment scores by DED subtype confirmed that the majority of patients reported scores in the range of 0– 5 for all components and in all subgroups analyzed.

Conclusion: Our study demonstrated that PG-HPG nanoemulsion provided instant/immediate and sustained symptom relief for 8 hours post-single application and was well tolerated in patients with DED, demonstrated by their responses on each of the assessment scales.

Keywords: aqueous-deficient dry eye, dry eye disease, evaporative dry eye, propylene glycol-hydroxypropyl guar nanoemulsion ocular lubricant, mixed dry eye

Srinivasan S, Jones L, Schulze M, Guillon M, Tauber J, Silverstein S, Yeu E, Venkiteshwar M. Efficacy of a propylene glycol/hydroxypropyl guar-based lubricant eye drop The Association for Research in Vision and Ophthalmology, 2020 [ Show Abstract ][ PDF ]

Purpose : SYSTANE® Complete (propylene glycol/hydroxypropyl guar [PG/HPG]) lubricant eye drop formulation developed using advanced nano-droplet technology, helps replenish a deficient tear film. This study evaluated the improvement in tear film break up time (TFBUT) after 14 days of treatment with PG/HPG lubricant eye drops in patients with dry eye disease (DED).

Methods : This was a Phase IV, multicenter, open-label, single-arm, interventional study. Adult patients with a clinical diagnosis of mild to moderate DED (subtyped into aqueous deficient (ADDE), evaporative dry eye (EDE) and mixed dry eye (MDE)) were included. Eligible patients received one drop of PG/HPG, twice daily. The change from baseline in fluorescein stained tear film break-up time (TFBUT) was assessed at Day 14. Data were analyzed for the overall cohort and by DED subtypes.

Results : Of 134 patients who received the study treatment, 131 completed the study. The median age of the study cohort was 59 (range: 18–87) years, and majority of patients were female (75.4%). Number of patients per subtype were similar (ADE=41; EDE=44; MDE=49). Overall, the median TFBUT increased from 2.68s at baseline to 3.32s at Day 14 (change from baseline= 0.81s; CI for the median = 0.52 -1.18). Subtype analysis showed a median change from baseline in TFBUT of 0.72s for ADDE (CI of median = 0.17-1.22), 1.32s for EDE (CI of median = 0.61-2.26), and 0.55s for MDE (CI of median = 0.07-1.03), at Day 14. The change in TFBUT values were significant overall as well as in the subtypes of DE. The maximum increase in tear film stability was noted in the EDE subgroup (59.2%).

Conclusions : PG/HPG lubricant eye drops increased tear film break up time in patients with DED, with an improvement reported in all dry eye subtypes at Day 14 of treatment. These results show that PG-HPG lubricant eye drops provide an increase in tear film stability in patients with DED.

This is a 2020 ARVO Annual Meeting abstract.

Tichenor,A,, Cofield,S., Gann,D., Elder,M., Ng,A. Y., Walsh,K., Jones,L., Nichols,J. Frequency of Contact Lens Complications Between Contact Lens Wearers Using Multipurpose Solutions Versus Hydrogen Peroxide in the United States and Canada Eye & Contact Lens 2020;Online ahead of print [ Show Abstract ]

Objectives: To retrospectively compare frequency of contact lens (CL) complications in soft CL users of hydrogen peroxide (H2O2) and multipurpose solutions (MPS).

Methods: This was a multicenter, retrospective chart review of CL records from each patient's three most recent eye examinations at academic and private practices. Patients must have used the same solution type for at least 3 years. Univariate analyses were conducted using t tests, and chi-square or Fisher's exact test for categorical measures.

Results: There were 1,137 patients included, with 670 (59%) using MPS and 467 (41%) H2O2. In total, 706 (62%) experienced at least one complication; 409 used MPS and 297 used H2O2. There was no difference in the proportion of patients experiencing at least one complication between MPS (61%) and H2O2 (64%) (P=0.38). Multipurpose solutions users were more likely to report discomfort compared with H2O2 users (P=0.04). Presumed microbial keratitis was experienced by 16 MPS and nine H2O2 users (P=0.60).

Conclusions: No significant differences were found in the frequency of CL complications between MPS and H2O2. H2O2 users were less likely to report discomfort and thus switching to a H2O2 system may be an alternative in CL users with discomfort.

Tse,J., Rizwan,M., Rasmussen,J., Jones,L., Yim,E. K. F. Gelatin Methacrylate as an Enzyme-Controlled Release Vehicle of Hyaluronic Acid for the Treatment of Recurrent Corneal Erosion Applied Bio Materials 2020;3(9):6214-6223 [ Show Abstract ]

Recurrent corneal erosion (RCE) is a condition where the superficial corneal epithelial cells sporadically shed because of poor attachment to the underlying basement membrane, resulting in pain and discomfort. RCE-afflicted corneas exhibit elevated biological factors and enzymes, such as matrix metalloproteinase (MMP)-9. Soft bandage contact lenses (BCLs) are a commonly recommended treatment as they permit continued vision during recovery. However, they do not outperform alternative treatments as they currently lack active ingredients for ocular surface repair. Development of BCLs with a sustained release of active ingredients to promote RCE wound healing over an extended period of time would be clinically valuable. We fabricated gelatin methacrylate (GelMA) hydrogels with MMP-9-triggered controlled release for further BCL development. GelMA disks were characterized to determine the optimal concentration and methacrylation degree for sustained release in the presence of MMP-9. The chosen active ingredient, 60 kDa hyaluronic acid (HA), was verified to promote wound healing in rabbit corneal epithelial cell and human corneal epithelial cell wound assays. The active ingredient was loaded into GelMA hydrogels, and the bioavailability of the vehicle was determined. The GelMA hydrogels revealed a tunable profile for diffusion and enzyme-mediated controlled release of a model molecule. The 60 kDa HA-loaded GelMA disks showed improvement in wound healing at HA loadings of 150 and 250 μg by improving the wound healing rates by 28% (68.7% wound closure) and 26% (67.9% wound closure), respectively, compared to the control (50.5% wound closure) at 24 h. The HA-loaded GelMA disks with 150 and 250 μg HA also exhibited shortened wound closure time of 75 h compared to >147 h with a bolus daily delivery of HA for wound closure. Overall, we demonstrated that the fabricated GelMA hydrogels offered an enzyme-triggered option as a sustained release material for future RCE treatments.

Ulkuseven,E., McCanna,D. J., Subbaraman,L. N., Jones,L. W. The Effect of Antimicrobial Peptides on the Viability of Human Corneal Epithelial Cells Probiotics and Antimicrobial Proteins 2020;Online ahead of print [ Show Abstract ]

Antimicrobial peptides are polypeptides composed of less than 100 amino acids and are a class of antibiotics with strong activity against some infectious bacteria. This study examined the safety of four chosen antimicrobial peptides using primary human corneal epithelial cells (HCEC) and explored their potential therapeutic use. The efficacy of the peptides was also studied by evaluating the minimum inhibitory concentrations (MIC) against Gram-negative and Gram-positive bacteria. One of the peptides (polymyxin E) was found to have antibacterial efficacy against a common Gram-negative bacterium (MIC 1.56 μg/mL for Pseudomonas aeruginosa), and another one (nisin) was found to have antibacterial efficacy against a common Gram-positive bacterium (MIC 125 μg/mL for Staphylococcus aureus). Metabolic activity and live/dead/apoptotic effects were measured with fluorescent dyes after HCEC were exposed to the peptides for 30 min. Three of the peptides exhibited lower toxicity against HCEC than a currently marketed eye drop product. Regarding both efficacy and safety, two of the peptides (polymyxin E and nisin) were found to have potential use for treating ocular infections.

van der Worp,E., Wolffsohn,J., Jones,L. When was the last time you fitted a soft lens? Cont Lens Anterior Eye 2020;43415-417 [ Show Abstract ]

A recent webinar “discussing the topic of soft lenses, examining dropout rates and putting forward suggestions for how eye care practitioners can ‘get control’ over their fitting” was hosted by the British Contact Lens Association (BCLA). However, the webinar and this editorial addresses much more than merely’ lens fitting’ and ‘dropouts.’ It seems that the profession is almost at a crossroads in which its future is defined by whether the profession stands as contact lens fitters and specialists or whether contact lenses are simply a commodity that can be sold over the internet.

van der Worp E, Jones L, Wolffsohn J. A clear vision on dropouts Global Specialty Lens Symposium, Las Vegas, USA, 2020

van der Worp E, Wolffsohn J, Jones L. Dropping the dropout rate Contact Lens Spectrum 2020;35, May: 36-43 [ Show Abstract ]

A review of soft lens types and fitting strategies that can help reduce the dropout rate among soft lens wearers.

At the 2020 Global Specialty Lens Symposium (GSLS), specialty lens topics from A to Z naturally dominated the program. However, soft lens fitting relating to all of its aspects is also one of the topics that the meeting covers, because the vast majority of contact lenses fitted worldwide are standard soft lenses, as confirmed by the annual Eurolens Research Survey published each year in the January issue of Contact Lens Spectrum.

Walsh K. Sharing the unique perspective of a practitioner, a patient, and a parent Global Myopia Symposium, Virtual Conference, September, 2020