We aimed to determine if multipurpose contact lens solutions could solely contribute to adverse ocular surface effects. Three specific multipurpose solutions were evaluated: Bausch & Lomb ReNu MultiPlus (ReNu with MoistureLoc was not evaluated in this study), Alcon No Rub Opti-Free Express, and Advanced Medical Optics Complete Moisture Plus. The impact that solutions have on the ocular surface, if negative, could be adverse. Nearly all recent studies examine the effects of solutions through the contact lens as a vehicle for delivery. The lens itself cannot be completely ruled out as a causal factor.
21 subjects were randomized to one of the three solution groups. Subjects self-administered a solution to their treatment eye four times daily, with the fellow eye serving as the control. Solutions and the test eye were masked to the subject and examiner. A battery of ocular surface testing was conducted at the baseline examination and at every week interval by masked examiner.
Non-parametric data was analyzed by Friedman 1-way ANOVA and parametric data by the 1-way repeated measures ANOVA. A reduction in tear breakup time was found to be statistically significant for the ReNu group (P < 0.05).
ReNu has frequently been cited as being more cytotoxic. We propose that when used at a high frequency, ReNu preservatives and additives are adverse. Contact lens dropout and/or clinical signs noted by the examiner may be linked to the use of ReNu.