Effect of lens care system on silicone hydrogel contact lens wettability

Abstract

Purpose: The purpose of this study was to compare the effect of the repeated usage of two different care systems (one hydrogen peroxide cleaning and disinfecting system and one PHMB containing multipurpose system) with silicone hydrogel lenses worn on a daily wear basis for a three month period. A specific aspect of interest was the study of effects of the care systems on contact lens wettability.

Methods: Seventy-four symptomatic contact lens wearers, currently wearing either ACUVUE® OASYS® (n=37) or PureVision (n=37), constituted the study population. The investigation was a two-arm prospective, bilateral study of three month duration to evaluate the potential beneficial effects of CLEAR CARE® compared with renu® fresh^TM. The subjects were randomized to use one of the two care systems. The effects on contact lens wettability were assessed with the Tearscope and reported in terms of Pre-lens Tear Film Non Invasive Break Up Time. Baseline assessments were carried out at the dispensing visit with new contact lenses. At the two and three month follow-up visits the contact lenses had been worn for at least six hours prior to the visits, and were at least 11 days old for ACUVUE® OASYS® and 25 days old for PureVision.

Results: The results obtained showed that: i. Whereas no difference in contact lens wettability was observed at dispensing between the two lens care groups (Mean Median NIBUT: 4.5 vs. 4.2s, p=0.518) a significantly more stable pre-lens tear film was observed with CLEAR CARE® than with renu® freshTM at both the two (Mean Median NIBUT: 4.6 vs. 3.7s p=0.005) and three (Mean Median NIBUT: 5.8 vs. 4.2s p=0.028) month visits. ii. With CLEAR CARE® a significant improvement in contact lens wettability was recorded compared with their habitual contact lenses and care system at three months (Mean Median NIBUT 5.8 vs. 4.0s p<0.001). Further, a significant increase in wettability was observed after three months of use compared with dispensing (Mean Median NIBUT 5.8 vs. 4.5s p=0.022). iii. With renu® fresh^TM, no significant differences were observed at the end of three months of use compared with either the subjects’ own care system or the new contact lenses at dispensing (Mean Median NIBUT: 3M 4.2 vs. Disp 4.2 (p=0.420) vs. Enrol 5.1s (p=0.734)).

Conclusions: Significantly better contact lens wettability was achieved for ACUVUE® OASYS® and PureVision with CLEAR CARE® than with renu® fresh^TM at the end of three months of use.

Keywords: 477 contact lens • 486 cornea: tears/tear film/dry eye