Jacqueline Tan

Impact of Contact Lens Material, Design, and Fitting on Discomfort.

Objective: To review the effect of contact lens (CL) material, design, and fitting characteristics on CL discomfort. Methods: A PubMed search identified publications describing subjective comfort and CL material, fitting, and design parameters. The review included clinical signs associated with discomfort that may be a consequence of these parameters. Results: Reduced lens movement or more CL tightness were associated with improved comfort. Increased lens-induced paralimbal conjunctival staining and indentation, considered as quasi-indicators of CL fitting or edge design, were also associated with better comfort. No recent studies have evaluated varying CL design parameters and subjective comfort. Silicone hydrogel CLs are no different in comfort compared with hydrogel CLs. Lower equilibrium water content is associated with improved comfort in hydrogel CL wear. Coefficient of friction shows promise as a material factor potentially associated with comfort. Lid wiper epitheliopathy and lid-parallel conjunctival folds have been linked with comfort in established wearers. Conclusions: Recent studies have confirmed the association between more mobile CLs and more discomfort, whereas closer conformity of the CL to the bulbar conjunctiva improved subjective comfort. There is no evidence to support the perceived comfort difference between silicone hydrogel and hydrogel CL. There has been limited progress in understanding the impact of varying specific CL design parameters. Although specific clinical signs may be predictive of discomfort, their role in the natural history of discomfort remains unclear. A better understanding of the relationship between coefficient of friction and comfort and strategies to improve lubricity may hold promise for limiting CL discomfort.

Clinical Outcomes and Contact Lens Case Contamination Using a Povidone-iodine Disinfection System.

Objective: To assess the incidence of adverse events during the use of a povidone–iodine disinfecting solution (cleadew) and the microbial contamination in contact lens cases. Methods: A prospective, single-center, open-label, controlled study evaluating the use of cleadew cleaning and disinfecting system in existing daily wear soft contact lens wearers over a 3-month period was conducted. Ocular signs and symptoms during lens wear were assessed at baseline and after 1 and 3 months of using cleadew. Contact lens cases were assessed for the frequency of microbial contamination and the types of microbes, using traditional microbial culture, followed by identification of bacteria using 16S rRNA sequencing. Results: Use of cleadew was well tolerated. There was reduction in corneal staining (0.5±0.5 at 3 months of use) compared with the participants habitual multipurpose disinfecting system (1.1±1.0); all other clinical signs were not significantly different. There were no cases of solution-induced corneal staining. There was a low adverse event rate of 0.8% per 100 participant-months. Contact lens case contamination was low, with 30% of cases having no culturable microbes. Comparison with previously published data showed that use of cleadew resulted in low frequencies of Gram-positive (49%) and fungal (8%) contamination and a low, but higher than some other disinfecting solutions, level of Gram-negative bacteria. Conclusions: Cleadew cleaning and disinfecting system was associated with low levels of adverse events during use. Contact lens cases were significantly less frequently contaminated than for some other types of disinfecting solutions.

Clinical Outcomes of Fixed Versus As-Needed Use of Artificial Tears in Dry Eye Disease: A 6-Week, Observer-Masked Phase 4 Clinical Trial

Purpose To evaluate the clinical effects of using fixed (four times daily [QID]) versus as-needed (PRN) dosing of an artificial tear product (polyethylene glycol/propylene glycol [PEG/PG]; Systane Ultra) in individuals with dry eye disease. Methods In this prospective, multicenter, observer-masked, active-control, parallel-group trial, participants were randomized (1:2 allocation) to receive 1 drop of PEG/PG QID (n = 34) or PRN (n = 63) for 28 days. The primary endpoint was change from baseline in the total ocular surface staining (TOSS) score (according to the Oxford scale) at day 28. Results At day 28, the change from baseline in least squares mean (LSM) TOSS scores for QID and PRN groups were -1.19 and -0.94, respectively (treatment difference [TD]: -0.26; 95% confidence interval [CI]: -∞ to 0.21; P = 0.184); superiority of QID versus PRN dosing was not established, as the upper limit of one-sided 95% CI for TD was not <0 (prespecified limit). At day 28, for QID and PRN groups, the LSM change from baseline in Impact of Dry Eye on Everyday Life (IDEEL) scores was symptom-bother, -7.0 and -2.94 (TD: -4.06, P = 0.037); treatment effectiveness, 2.43 and 0.16 (TD: 2.28, P = 0.278); and treatment-related inconvenience, -11.56 and -2.77 (TD: -8.8, P = 0.996), respectively. Incidence of adverse events was low (≤3.2%) in both the groups; no serious adverse events were reported. Conclusions QID dosing of PEG/PG was not superior to PRN dosing in terms of ocular staining. The IDEEL symptom-bother score favored QID dosing, suggesting that regular use of artificial tears may provide better symptomatic relief than PRN use. (ClinicalTrials.gov number, NCT02446015.).

The effects of a hydrating mask compared to traditional warm compresses on tear film properties in meibomian gland dysfunction

• Bruder Eye Hydrating Compress increases tear film lipid layer thickness after a single treatment.

The eyelids and tear film in contact lens discomfort

PURPOSE To investigate characteristics of the eyelid margins, meibomian glands and the tear film of contact lens wearers, and to determine whether these characteristics were related to symptoms of contact lens discomfort. METHODS A cross sectional study was performed on thirty existing daily wear soft contact lens wearers (6 male; 24 female) with median age of 23 years (range 18-41). Eyelid signs and tear film characteristics were evaluated during a single visit and subjects completed the contact lens and dry eye questionnaire (CLDEQ-8) to evaluate ocular discomfort. RESULTS Based on the CLDEQ-8 responses, subjects were classified as symptomatic (n = 17) or asymptomatic (n = 13). Grades of foam at meibomian gland orifices (3 ± 1), expressibility (2 ± 1) and quality of secretions (2 ± 1), tear evaporation rate with (112 ± 54 g/m2/h) or without (88 ± 45 g/m2/h) contact lens wear, fluorescein tear breakup time (8 ± 2 seconds) and tear lipid layer thickness (45 ± 17 nm) were significantly associated with symptoms of discomfort in symptomatic lens wearers only (r2 > 0.45; p value < 0.05). Upper lid-wiper epitheliopathy, meibomian gland acini reflectivity and tear meniscus height showed significant correlations with comfort scores in both symptomatic and asymptomatic contact lens wearers (p < 0.05). A greater number of Demodex mites was also observed in the upper eyelid of symptomatic lens wearers (2 ± 1) compared to asymptomatic lens wearers (0 ± 0; p value = 0.042). CONCLUSIONS Morphological irregularities of the meibomian glands and alterations to tear film secretions that affect tear evaporative dynamics were associated with symptoms of discomfort amongst the symptomatic lens wearers.