Comparative cytotoxicity potential of soft contact lens care regimens.

Abstract

PURPOSE To determine the cytotoxicity potential of soft contact lens disinfection solutions. METHODS Three modifications of the United States Pharmacopeia (USP) elution test were conducted: trypan blue uptake test; regrowth of cells after exposure; and quantitation of viable cells after exposure test. Cycled lenses were also tested according to the USP direct-contact test. We compared the cytotoxicity profile of neutralized AOSept (CIBA Vision, Duluth, GA) disinfectant, SOLO-care Soft (CIBA Vision, Duluth, GA) brand multipurpose solution, OPTI-FREE Express (Alcon, Ft. Worth, TX) multipurpose disinfecting solution (with ALDOX), ReNu (Bausch & Lomb, Rochester, NY) multipurpose solution, ReNu MultiPlus (Bausch & Lomb, Rochester, NY) multipurpose solution, and COMPLETE Comfort PLUS (Allergan, Irvine, CA) multipurpose solution. Appropriate positive and negative controls were used for each test. RESULTS Neutralized AOSept, SOLO-care soft, and COMPLETE Comfort PLUS solutions were noncytotoxic by all four test methods. ReNu MPS and ReNu MultiPlus both were noncytotoxic by the USP direct contact test and the USP elution-based trypan blue uptake and cell regrowth tests, but both yielded less than 50% of viable cells. In the three USP Elution test methods, OPTI-FREE Express (with ALDOX) exhibited cytotoxicity. CONCLUSIONS These solutions have shown widely varying cytotoxicity potential. Neutralized AOSept, SOLO-Care Soft, and COMPLETE Comfort Plus were noncytotoxic by all four tests. ReNu MultiPlus and ReNu MPS inhibited the growth of cells after exposure. OPTI-FREE Express (with ALDOX) may have a higher potential for ocular irritation correlating to severe cytotoxicity in vitro.