Evaluation of Rinsing Options for Rigid Gas Permeable Contact Lenses

Abstract

Objectives: This study assessed the efficacy of various saline solutions as alternative methods to rinsing rigid gas permeable (RGP) lenses with tap water. Methods: The exiting fluid pressure of five commercially available saline solutions was measured using a venous pressure transducer system. Rigid gas permeable lenses were cleaned with one of two commercially available cleaners and then rinsed with one of five saline solutions or with tap water. High-resolution imaging was performed after each rinse, and light transmission through the lens surface was determined by measuring the mean pixel count within a 1 mm by 1 mm square. Results: The mean pixels/mm2 and the rinsing method were correlated (Spearman rank order correlation, P<0.0001), that is, high pixel counts represented more lens surface deposits and residue, and as fluid pressure of the rinsing methods increased, mean pixels/mm2 decreased. Conclusions: Measured fluid pressure relates to lens surface opacity suggesting that some products leave less residue than others. In addition, tap water, with its high exiting fluid pressure, seems to be the most effective option for removal of RGP cleaners from the contact lens surface. Despite these findings, tap water rinse is not encouraged because of its potential to lead to corneal inflammation and infection; therefore, the development of alternative procedures and products is needed.