In-Office Microwave Disinfection of Soft Contact Lenses

Abstract

We evaluated the effectiveness of an in-office microwave disinfection procedure which allowed for the disinfection of up to 40 soft contact lenses at one time. Ciba AOSept cases filled with sterile unpreserved saline were contaminated with one of six FDA test challenge microorganisms at a concentration of approximately 10(3) colony forming units per milliliter (CFU/ml). Twenty cases were placed on the rotating plate of a standard 2450 MHz 650 W microwave oven in a 10-cm diameter circle. The cases were exposed to high intensity microwave irradiation for periods of 0 to 15 min. None of the 6 microorganisms evaluated survived 2 min or longer of microwave exposure. Our findings indicated that microwave irradiation can be a convenient, rapid, and effective method of disinfecting a number of soft contact lenses at one time and thus adaptable as an in-office soft contact lens disinfection procedure.