Abstract
Retrospective analysis of different contact lens wearing groups suggests lens surface lubricity is the main factor influencing contact lens comfort. However, the examined commercially available contact lenses differ in material and design as well as surface properties. Hence this study isolates the contribution of lens surface properties using an ultra-thin coating technology. Nineteen habitual contact lens wearers (21.6±1.7years) wore formofilcon B soft monthly disposable contact lenses with and without coating technology modified surface properties for a month each in a randomised double-masked cross-over study. OBJECTIVE NON-INVASIVE: breakup time (NIKBUT), NIKBUT average and ocular redness (Jenvis grading scale) were evaluated (Keratograph 5M) after 1 week and 1 month of wear. Symptoms were assessed using the Contact Lens Dry Eye Questionnaire (CLDEQ-8); perceived vision quality and subjective lens comfort at insertion, mid-day and end of the day were rated with four Visual Analog Scales. Perceived visual quality (F=5.049,p=0.037), contact lens dry eye symptoms (F=14.408,p=0.001) and subjective lens comfort (F=28.447,p<0.001) were better for coated compared to uncoated lenses. The surface coating postponed the lens dewetting (F=8.518,p=0.009) and increased the pre-lens tear film stability (F=5.626,p=0.029), but bulbar (F=0.340,p=0.567) and limbal (F=0.110,p=0.744) redness were similar for both contact lenses. No parameter changed significantly between a weeks' and months' wear (p>0.05). Lens surface wettability and ocular redness were not correlated to changes in symptoms (p>0.05). As previously hypothesised, enhancing the physical surface properties of a soft contact lens improves subjectively rated wearer comfort, which, in turn, should result in reduced contact lens discontinuation.
Highlights
The management of contact lens discomfort (CLD) remains a challenge in clinical practice [1]
The current investigation is the first to examine the isolated effect of reducing lens surface friction on lens comfort and wettability by adding a thin coating to a standard silicone hydrogel
These differences were low compared to the range of these parameters across currently available commercial soft contact lenses
Summary
The management of contact lens discomfort (CLD) remains a challenge in clinical practice [1]. Ocular dryness decreases after lens removal, [5] and generally reduces during the afternoon and evening when wearing contact lenses [4,5,6,7,8]. Current studies have suggested that the friction between lens surface and lid margin (termed lubricity) is the key contributor to lens comfort [26,27,28,29]; they use commercially available contact lenses which differ in material and design and are generally worn by different cohorts of patients, introducing potential confounding effects. This study applied a nanometer thickness coating technology (without significantly altering lens design or core material properties) to monthly disposable silicone hydrogel lenses to determine whether surface properties alone affect lens comfort and wettability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
