In three patients (three men, 44, 67, and 83 years old) an unusual keratopathy characterized by white, branching, crystalline stromal opacities produced lesions that were insidious, that increased in size slowly, and that were clinically and histopathologically associated with little corneal inflammation. Intraocular inflammation eventually became evident in two of the patients. The keratopathy developed while the patients were using topical corticosteroids. In two cases, histopathologic studies disclosed accumulations of gram-positive cocci in the corneal stroma; a viridans streptococcus agent was isolated on culture. In one case, the viridans streptococcus was determined to be a dextran producer, which may have contributed to the pathogenesis of the keratopathy. Despite aggressive treatment with a variety of drugs, epithelial healing, and resolution of the corneal infiltrate, residual scarring persisted in two cases and neovascularization and graft edema in one case each.