Microbiological aspects of extended-wear soft contact lenses.

Corneal ulcers are the most devastating complication associated with extended-wear soft contact lenses. The increasing prevalence of microbial keratitis associated with the wear of these lenses is a major concern for the optometrist. Studies of extended-wear and daily-wear contact lens patients strongly suggest that extended-wear patients face a greater risk of ulcerative keratitis than other cosmetic contact lens wearers. This discussion addresses the potential risks of extended-wear, with emphasis on ulcerative keratitis, the likely causes for these increased risks, and what the optometrist can do to reduce the risk of a microbial infection.