This document discusses Herpes simplex keratitis, which is caused by the herpes simplex virus (HSV). It outlines the different types of herpetic eye disease including epithelial keratitis, disciform keratitis, necrotizing stromal keratitis, and neurotrophic ulceration. Epithelial keratitis presents with redness, photophobia, and a linear-branching ulcer. Disciform keratitis causes blurred vision and stromal edema. Necrotizing stromal keratitis results in stromal necrosis and melting. Neurotrophic ulceration is caused by corneal anesthesia. Treatment involves antiviral medications like acyclovir as well as steroids. Long term antiviral pro