In vitro comparison of soaking solutions for rigid gas-permeable contact lenses

The comfort of rigid gas-permeable contact lenses is influenced by multiple factors, including the composition of lens material and the presence of surface deposits and/or cleaning solution residues on the lens, as well as the direct effect of lens care solutions on the lens and eye. This study was designed to examine the comparative properties of several soaking solutions with respect to wettability, viscosity, and substantivity, which are essential to maintaining patient comfort. Solutions included in this trial were: OPTI-SOAK Conditioning Solution, Boston Advance Conditioning Solution, Boston Advance Conditioning Solution, Boston Conditioning Solution, Barnes-Hind Wetting and Soaking Solution, Duracare Conditioning, and Total Cleaning, Wetting & Soaking Solution. Wettability, as indicated by mean wetting angle, was determined and OPTI-SOAK Conditioning Solution, followed by Boston Advance and Boston Conditioning solutions, respectively, yielded superior results. For viscosity, OPTI-SOAK Conditioning Solution again provided the most favorable (highest) viscosity, followed by Boston Conditioning and Barnes-Hind solutions. With regard to substantivity, a measure of sustained wettability, Boston Conditioning Solution achieved the highest measurement, followed by OPTI-SOAK and Boston Advance solutions. On the basis of this in vitro evaluation, OPTI-SOAK Conditioning Solution provided the highest potential for patient comfort based on a combination of wettability, viscosity, and substantivity.