Publications

Showing 25 results out of 100 in total.

Ng AY. CLEAR report summary: Contact Lens Complications https://contactlensupdate.com/2021/06/15/contact-lens-complications/ 2021

Ng AY, Yang M. Why you shouldn’t neglect eye care during the pandemic The Conversation 2021;March 7 [ Show Abstract ]

Since COVID-19 emerged, access to eye care has continued to change. Lockdowns and concerns about virus exposure have caused people of all ages to cancel and delay routine appointments, raising red flags among eye-care professionals. As the pandemic continues into its second year, can ocular health be neglected any longer?

Our team of optometrists and clinical scientists at the Centre for Ocular Research & Education (CORE) hear the confusion and concerns about people’s eyes during COVID-19. Addressing the most common questions — many of which we keep up to date at COVIDeyefacts.org — can help you and your family maintain the best vision while staying safe.

Ng AY, Yumori J. Rethinking Eye Cosmetics and Cosmetic Procedures: What Should We be Telling Our Patients? Best of Boston Academy (Virtual), 2021 [ Show Abstract ]

Cosmetics are used widely to enhance our appearance, clean, and maintain the condition of our skin. With face mask-wearing on the rise many cosmetic users are choosing to accentuate their eyes further with eye cosmetics. However, patients might not have considered the effects that some eye cosmetic products and procedures may have on their eyes. This session will explore the complications that can arise from some common products and procedures, and highlight points of discussion where we should be engaging with our patients.

Ngo W. CLEAR report summary: Anatomy and Physiology of the Anterior Eye https://contactlensupdate.com/2021/06/15/anatomy-and-physiology-of-the-anterior-eye/ 2021

Ngo W.. Face masks, digital screens and winter weather are a triple threat for dry eyes The Conversation 2021;December 16

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., 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., 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.

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) < 8 h and a noticeable reduction in comfort over the course of the day) and asymptomatic (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.

Patel K, Draper M, Bull Z, Walsh K. Contact lenses: So much more than simple correction of refractive error Optician 2021, February: 25-29

Patel K, Walsh K. Soft toric contact lenses: Aligning patient expectations and eye care professional attitudes Optician 2021, March: 32-36 [ Show Abstract ]

In this article Krupa Patel and Karen Walsh examine the expectations around soft toric lenses from both the practitioner and patient’s point of view. It serves as a timely review of current toric fitting practices and how they relate to the prevalence of astigmatism, highlighting a number of opportunities for enhancing patient satisfaction and increasing practice revenue (C77594, one distance learning CET point suitable for optometrists, contact lens opticians and dispensing opticians).
Some simple facts help set the scene for this global review. It has been established that modern soft toric contact lenses are as quick and simple to fit as spherical lenses, with good visual outcomes and rotational stability across many visual tasks. However, when 400 eye care professionals (ECPs) in the US were asked, only around half agreed soft torics are as easy to fit as the equivalent spherical lens (49%), and that they have excellent rotational recovery (55%). How does this disparity between reported product performance and practitioner attitude influence fitting practices? Ultimately, what is the impact on patients, and how close does current practice come to meeting their
expectations?

Phan,C. M., Qiao,H., Yee,A., Jones,L. Deposition of Fluorescently Tagged Lysozyme on Contact Lenses in a Physiological Blink Model Eye & Contact Lens 2021;47(2):127-133 [ Show Abstract ]

PURPOSE: To visualize the deposition of fluorescein isothiocyanate (FITC) lysozyme on daily disposable contact lenses (CLs) using a novel blink model.

METHODS: Three daily disposable conventional hydrogel CLs (etafilcon A, omafilcon A, and nelfilcon A) and three silicone hydrogel CLs (delefilcon A, senofilcon A, and somofilcon A) were evaluated in the study. The CLs were mounted onto a novel blink model and exposed to an artificial tear solution containing FITC lysozyme for 2 and 10 hr. The flow rate and blink speed were set to 1 μL/min and 6 blinks/min, respectively. After the incubation period, a 5-mm-diameter disc was punched out from the center of the lens and mounted on a microscope slide. The slides were imaged using the Zeiss 510 Meta confocal laser scanning microscope, which scanned the lens from the front to the back surface at 5-μm increments.

RESULTS: There was an increase in deposition of FITC lysozyme for all lens types with increasing incubation time (P<0.05), with the exception of somofilcon A, which did not show statistical significance between 2 and 10 hr (P>0.05). The conventional hydrogel CLs deposited higher amounts of FITC lysozyme than the silicone hydrogel CLs (P<0.001), with etafilcon A depositing the highest at all time points (P<0.05). Interestingly, at the 2-hr incubation time, most CLs showed a higher amount of deposition at the front surface than the back surface of the lens. In particular, etafilcon A showed preferred deposition at the front surface at all time points.

CONCLUSION: The results suggest that there is differential deposition at the front surface of the CL, which is exposed to the prelens tear film, compared with the back surface of the CL, which is exposed to the postlens tear film. Therefore, it may be beneficial to design CL materials with differing surface properties for the front and back surfaces of the CL to enhance interactions with the tear film and ocular surface.

Phan,C. M., Shukla,M., Walther,H., Heynen,M., Suh,D., Jones,L. Development of an In Vitro Blink Model for Ophthalmic Drug Delivery Pharmaceutics 2021;13(Article 300):1-10 [ Show Abstract ]

Purpose: The purpose of this study was to develop an advanced in vitro blink model that
can be used to examine the release of a wide variety of components (for example, topical ophthalmic
drugs, comfort-inducing agents) from soft contact lenses. Methods: The model was designed using
computer-aided design software and printed using a stereolithography 3D printer. The eyelid and
eyeball were synthesized from polyvinyl alcohol and silicone material, respectively. Simulated
tear fluid was infused through tubing attached to the eyelid using a syringe pump. With each
blink cycle, the eyelid slides and flexes across the eyeball to create an artificial tear film layer. The
flow-through fluid was collected using a specialized trough. Two contact lenses, etafilcon A and
senofilcon A, were incubated in 2 mL of a water-soluble red dye for 24 h and then placed on the eye
model (n = 3). The release of the dye was measured over 24 h using a tear flow rate of 5 µL/min.
Results: Approximately 25% of the fluid that flowed over the eye model was lost due to evaporation,
nonspecific absorption, and residual dead volume. Senofilcon A absorbed more dye (47.6 ± 2.7 µL)
than etafilcon A (22.3 ± 2.0 µL). For etafilcon A, the release of the dye followed a burst-plateau
profile in the vial but was sustained in the eye model. For senofilcon A, the release of the dye was
sustained in both the vial and the eye model, though more dye was released in the vial (p < 0.05).
Overall, the release of the dye from the contact lenses was higher in the vial compared with the eye
model (p < 0.05). 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. Simulation of a blink
mechanism, an artificial tear film, and nonspecific absorption in an eye model may provide better
results than a simple, static vial incubation model.

Phan C. CLEAR report summary: Contact Lens Technologies of the Future https://contactlensupdate.com/2021/06/15/contact-lens-technologies-of-the-future/ 2021

Phan C. Can we simulate the anterior eye to further improve contact lenses of the future? BCLA Virtual Clinical Conference & Exhibition, June 13, 2021

Ranch KM, Shukla MR, Maulvi FA, Desai DT. Chapter 7: Carbon-based nanoparticles and dendrimers for delivery of combination drugs In: Nanocarriers for the Delivery of Combination Drugs , ed. Baboota S, Ali J. Elsevier Inc.. 2021.

Rueff,E., Tichenor,A. A., Ngo,W., Pucker,A. D. A review of meibomian gland structure, function, and contact lens wear Contact Lens Anterior Eye 2021;Online ahead of print [ Show Abstract ]

Purpose: To provide a balanced literature review of the studies that have evaluated the effect of contact lenses on meibomian gland (MG) health.

Methods: A PubMed.gov literature search was conducted on or before May 15, 2021. No other time constraints were applied. Search terms included the following: "meibomian gland(s)" plus "contact lens(es)" or "meibography" plus "contact lens(es)". Only full text articles written in English were considered. The reference lists of recovered papers were used to identify articles missed during the primary search. Included articles were required to discuss the impact of contact lenses on MG morphology or function and were graded according to the level of evidence presented.

Results: The literature indicates that contact lenses impact MG function; however, the data are equivocal regarding contact lenses inducing MG structural changes. The literature likewise indicates that the mechanism(s) by which contact lenses impact the MGs are likely multifactorial. Recent data suggests that MGs may have some plasticity. Detected differences between studies likely stem from varied populations evaluated, study designs, and the duration of the evaluation periods.

Conclusions: With this literature review finding conflicting relationships between MG health and contact lens use, future longitudinal studies with standardized clinical MG assessments are needed to determine the true impact of contact lenses on MG health. Until these data are obtained, contact lens wearers should undergo a full MG evaluation, especially because recent data suggest that MG treatments may restore MG structure and function.

Schulze,M., Ng,A. Y., Yang,M., Panjwani,F., Srinivasan,S., Jones,L., Senchyna,M. Bulbar redness and dry eye disease: comparison of a validated subjective grading scale and an objective automated method Optometry & Vision Science 2021;98(2):113-120 [ Show Abstract ]

SIGNIFICANCE
In this study, assessments of conjunctival redness were performed to evaluate whether patients with or without dry eye disease (DED) could be discriminated based on this measure. Our findings suggest that subjectively grading redness by quadrant, as opposed to automated en face measurements, may be more suitable for this purpose.

PURPOSE
This study aimed to quantify bulbar redness using the validated bulbar redness (VBR) grading scale and an automated objective method (Oculus Keratograph 5M; K5M) in participants with DED and non-DED controls.

METHODS
Participants with DED (Ocular Surface Disease Index score ≥20 and Oxford scale corneal staining ≥2) and controls (Ocular Surface Disease Index score ≤10 and corneal staining ≤1) attended two study visits. In part 1A of visit 1, baseline bulbar redness was graded with the VBR scale in each conjunctival quadrant of both eyes, followed by automated measurements of temporal and nasal redness with the K5M. This was immediately followed by part 1B, during which a topical vasoconstrictor was instilled into both eyes. Redness assessments were repeated 5 and 30 minutes after instillation with both instruments. Participants returned 14 days later for visit 2, where the same assessments as for visit 1A were repeated.

RESULTS
Seventy-four participants (50 DED and 24 controls) completed the study. There were statistically significant differences in redness between the DED and control groups when assessed with the VBR scale (14/16 comparisons; all, P < .05), whereas no significant differences in K5M-derived redness between the DED and non-DED groups were found at any location or time point. Both subjective and objective instruments detected statistically significant reductions in redness 5 and 30 minutes after instillation of the vasoconstrictor (all, P < .01).

CONCLUSIONS
Although both subjective and objective instruments were sensitive to detecting changes in redness induced by vasoconstriction, statistically significant differences in redness between DED and control groups were only found using the VBR scale.

Schulze M. CLEAR report summary: Contact Lens Optics https://contactlensupdate.com/2021/06/15/contact-lens-optics/ 2021

Schulze M, Luensmann D, Woods J, Vega J, Orsborn G.. Comfort and vision with two daily disposable multifocal lenses when worn by habitual multifocal contact lens wearers BCLA Virtual Clinical Conference & Exhibition, 2021 [ Show Abstract ][ PDF ]

Purpose: Practitioners can be reluctant to switch successful multifocal soft contact lens (MF) wearers to different materials or replacement frequencies, fearing the new MF will be less accepted. Subjective responses are highly valued in MF fitting and this study investigated subjective responses from habitual MF (hab-MF) wearers after a refit into daily disposable MF; stenfilcon A (stenA-MF) and delefilcon A (delA-MF).

Method: After optimising the lens powers, subjects wore hab-MF and both study-MFs for 2-weeks each. Study-MF brands were masked and randomised. Throughout the study, subjects answered 13 experience questions per lens type, and 6 preference questions (comfort and vision for distance, intermediate, near, digital-device use, overall vision) to compare between hab-MF and each study MF, and also between study MFs.

Results: Fifty-eight subjects (50F:8M), mean age 54.4±7.3 years were included. Mean spherical-equivalent OD refraction: -1.10±2.7D [range -6.50D to +3.75D], mean near add +2.00±0.4D. 44% habitually wore daily disposable MF yet all were naïve to the study-MFs. Hab-MF wear resulted in positive responses for all experience questions (p<0.05); for stenA-MF 12 answers were positive (p<0.05), 1 was equivocal (p=0.90); for delA-MF 6 were positive (p<0.05), 7 were equivocal (p>0.05). Preferences between stenA-MF and hab-MF showed no differences (p>0.05). Subjects preferred hab-MF over delA-MF for intermediate vision (p=0.03) but no other preference (p>0.05). Comparing between study MFs, the preference for stenA-MF was stronger than delA-MF for comfort (p=0.03), intermediate vision (p=0.03), digital-device use (p=0.03) and overall vision (p=0.02) with no difference for distance or near vision (p>0.05).

Conclusions: This study showed that even when habitual MF wearers are already successful, refitting with a new design does not necessarily lead to compromised performance; stenA-MF performed comparably to hab-MF, and for some metrics better than delA-MF. These results should give practitioners confidence to recommend newer materials and different replacement frequencies when managing their existing MF wearers.

Spafford,M. M., Jones,D. A., Christian,L. W., Labreche,T., Furtado,N. M., MacIver,S., Irving,E. L. What the Canadian public (mis)understands about eyes and eye care Clinical and Experimental Optometry 2021;Online ahead of print [ Show Abstract ]

Clinical relevance
Inadequate public knowledge about eyes and eye care poses avoidable risks to vision-related quality of life.

Background
This study of eye care knowledge among Canadians extends earlier findings from focus groups.

Methods
Perceptions about eyes and eye care were sought using a 21-item online survey and snowball sampling. Inclusion criteria were living in Canada and being at least 18-years old; eye care professionals and staff were excluded. Response frequencies were converted to percentages, with eye condition items analysed according to ‘expected’ or ‘unexpected’ eye impacts. Proportions selecting these impacts or ‘unsure’ were determined.

Results
There were 424 respondents: 83.0% aged 20-65 years and 69.6% female. Mismatches existed between perceived recommendations and behaviours for booking eye exams: within two years (86.7% vs. 68.4%) and symptom-driven (3.3% vs. 13.0%). First eye exams after age one year were deemed appropriate by 43.6%. Few respondents associated glaucoma with no symptoms (6.0%) or amblyopia with blurred vision (13.5%). A notable proportion incorrectly related tunnel vision with age-related macular degeneration (AMD, 36.8%) and cataract (21.9%). Identifying all ‘expected’ responses was unlikely for glaucoma (1.9%), amblyopia (6.7%), and cataract (12.0%). Most respondents identified no ‘expected’ effects for glaucoma (63.8%) and AMD (46.2%) and some ‘expected’ effects for cataract (59.5%) and amblyopia (72.6%). Selecting ‘unsure’ was 9-10 times more common among respondents choosing no ‘expected’ impacts than those choosing some. Awareness of thyroid-associated eye disease was lowest (32.4%) of seven conditions. Respondents were most likely to consult optometrists for routine eye exams, eye disease, diabetes eye checks and blurred vision but family physicians for red eyes and sore eyes. Respondents typically paid for their eye exams and eyewear but wanted government to pay.

Conclusion
Vision-threatening knowledge gaps and misinformation about eyes and eye care among Canadian respondents highlight the need for accessible, targeted public education.

Stapleton,F., Bakkar,M., Carnt,N., Chalmers,R., Kumar Vijay,A., Marasini,S., Ng,A. Y., Tam,J., Wagner,H., Woods,C., Wolffsohn,J. S. CLEAR - Contact lens complications Contact Lens Anterior Eye 2021;44(2):330-367 [ Show Abstract ]

Contact lens-related complications are common, affecting around one third of wearers, although most are mild and easily managed. Contact lenses have well-defined anatomical and physiological effects on the ocular surface and can result in other consequences due to the presence of a biologically active material. A contact lens interacts with the tear film, ocular surface, skin, endogenous and environmental microorganisms, components of care solutions and other antigens which may result in disease specific to contact lens wear, such as metabolic or hypersensitivity disorders. Contact lens wear may also modify the epidemiology or pathophysiology of recognised conditions, such as papillary conjunctivitis or microbial keratitis. Wearers may also present with intercurrent disease, meaning concomitant or pre-existing conditions unrelated to contact lens wear, such as allergic eye disease or blepharitis, which may complicate the diagnosis and management of contact lens-related disease.

Complications can be grouped into corneal infection (microbial keratitis), corneal inflammation (sterile keratitis), metabolic conditions (epithelial: microcysts, vacuoles, bullae, tight lens syndrome, epithelial oedema; stromal: superficial and deep neovascularisation, stromal oedema [striae/folds], endothelial: blebs, polymegethism/ pleomorphism), mechanical (corneal abrasion, corneal erosion, lens binding, warpage/refractive error changes; superior epithelial arcuate lesion, mucin balls, conjunctival epithelial flaps, ptosis, discomfort), toxic and allergic disorders (papillary conjunctivitis, solution-induced corneal staining, incomplete neutralisation of peroxide, Limbal Stem Cell Deficiency), tear resurfacing disorders/dry eye (contact lens-induced dry eye, Meibomian gland dysfunction, lid wiper epitheliopathy, lid parallel conjunctival folds, inferior closure stain, 3 and 9 o'clock stain, dellen, dimple veil) or contact lens discomfort. This report summarises the best available evidence for the classification, epidemiology, pathophysiology, management and prevention of contact lens-related complications in addition to presenting strategies for optimising contact lens wear.

Thite,N., Desiato,A., Shinde,L., Wolffsohn,J. S., Naroo,S. A., Santodomingo-Rubido,J., Cho,P., Jones,D., Villar-Collar,C., Carillo,G., Chan,O., Wang,H., Iomdina,E., Tattura,E., Proskurina,O., Shing Fan,C., Zeri,F., Bakkar,M. M., Barodawala,F., Dabral,N., Lafosse,E., Lee,C., Nichols,J. J., Chan,J., Park,K., Nair,V., van der Worp,E., Vankudre,G., Maseedupalli,V., Bhattarai,Y., Nagzarkar,D., Brauer,P., Gil-Cazorla,R. Opportunities and threats to contact lens practice: A global survey perspective Contact Lens Anterior Eye 2021;44(6):101496 [ Show Abstract ]

Aim
To understand the views of contact lens (CL) practitioners across the globe regarding what they perceive as opportunities and threats in CL practice.

Methods
A self-administered anonymised questionnaire, constructed in English and translated in six more languages, was distributed through reputed international professional bodies and academic institutions worldwide. The questionnaire included items on demographic characteristics, type of practice, and questions designed to explore practitioners’ perspective on the future of their CL practice over the next five years.

Results
A total of 2408 valid responses were analysed. Multifocal CLs for presbyopia, CLs for myopia control, use of daily disposable (DD) CLs for occasional wear, and biocompatible materials to improve comfort were identified as promising areas of opportunities by practitioners (all 8/10). Respondents from North America, and Europe valued DDCLs for occasional wear moderately more favourable (Median: 9/10 for all) as compared to colleagues in Asia (Median: 8/10, p < 0.001), South America (Median: 8/10, p < 0.01), and Africa (Median: 8/10p < 0.01). Multifocal CLs for presbyopia was perceived as a better opportunity by practitioners in North America and Europe (Median: 9/10 for both), as well as in Australasia (Median: 8/10), in comparison to Asia, Africa, and Middle East (for all Median: 6/10, p < 0.001). Practitioners expressed concerns about the availability of CLs and CL prescriptions online without direct professional involvement (both 9/10).

Conclusions
Overall, the most appealing opportunities for CL practice growth were identified in occasional use of DD CLs, biocompatible materials to reduce CL discomfort, multifocal CLs for presbyopia correction and management of myopia control with CLs. Lack of regulation in CL sales, especially online, seemed to be a constant threat. The insights from this study can be used to design targeted strategies to enhance CL practice across the globe and in specific geographical areas.

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 2021;47(5):277-282 [ 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.

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 2021;13(2):518-526 [ 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.