Abstract
Purpose: :
Corneal staining induced by contact lens (CL) and multi-purpose solution (MPS) combinations has previously been reported as an indicator of ocular surface cytotoxicity. This study aims to investigate the clinical performance of two CL-MPS combinations by the determination of their corneal staining profiles, defined as corneal staining levels measured as a function of lens wear duration.
Methods: :
An investigational MPS and Opti-Free RepleniSH MPS (Alcon) were evaluated with balafilcon A (PureVision, Bausch & Lomb) silicone hydrogel CLs in a doubled-masked, paired-eye comparison at specific lens wear-times. Thirty subjects were randomized to wear one lens soaked in the investigational MPS in one eye and another lens soaked in Opti-Free RepleniSH MPS in the contralateral eye. Baseline evaluations were conducted after a minimum 12-hour washout period just prior to lens wear on each day of the study. Follow-up visits occurred after 1, 2, 4 and 6 or more hours (end-of-day) of lens wear. Corneal staining severity and extent (assessed on a five-point scale), subjective comfort and visual acuity were assessed at each study visit.
Results: :
No significant differences in corneal staining severity were observed between the mean scores of either CL-MPS combination at any post-insertion time point. The incidence and degree of change from baseline in corneal staining extent were generally observed to be greater in subjects wearing Opti-Free RepleniSH MPS-treated lenses. Subjects wearing Opti-Free RepleniSH MPS-treated lenses demonstrated significantly greater levels of corneal staining extent at the 2-hour time point (p=0.037) and a significantly greater change from baseline corneal staining extent (p=0.046) compared to that with the investigational MPS. A significantly higher number of subjects reported a preference for the investigational MPS over Opti-Free RepleniSH MPS at the 4-hour time point (p=0.021).
Conclusions: :
Results from this study illustrated that comparison of MPS-CL combinations can be well-characterized by corneal staining profiles that present staining as a function of lens wear time. This study also demonstrated that the investigational MPS out-performed Opti-Free RepleniSH MPS in both objective (corneal staining extent) and subjective (solution preference) measures.
Clinical Trial: :
www.clinicaltrials.gov NCT01024855
Keywords: contact lens • cornea: clinical science • clinical research methodology