Corneal exhaustion syndrome with long-term wear of contact lenses.

After many years of successful contact lens wear, 3 long-term wearers of polymethyl methacrylate (PMMA) lenses (14, 15, and 18 years) and 1 long-term wearer of thick hydrogel lenses (11 years) suddenly developed intolerance to their lenses. Symptoms included ocular discomfort, reduced vision, and photophobia. All patients exhibited an excessive open-eye edema response with low to moderate Dk lenses. Posterior corneal changes included distortion of the endothelial mosaic and moderate to severe endothelial polymegethism. Patients were successfully refitted with lenses having higher oxygen transmissibility. It is proposed that long-term hypoxia and acidosis accompanying PMMA and thick hydrogel contact lens wear may be responsible for a syndrome characterized by endothelial dysfunction which results in inadequate regulation of corneal hydration and subsequent intolerance to contact lens wear. This condition has been termed Corneal Exhaustion Syndrome (CES).