General Medical Information

Keratitis

Jean Edwards Holt

Keratitis is inflammation of the cornea. Although often mild, this condition can be dangerous and threaten vision. Disruption of and infiltrates in the cornea always produce pain, photophobia, and decreased vision. The conjunctiva is injected, and iritis may be present. Keratitis caused by the herpes simplex virus is an important ocular condition. The infection typically forms a branching dendritic pattern on the cornea. If recognized before corneal scarring occurs, the infection can be controlled with any of several antiviral medications. Iridocyclitis can be caused by the herpes zoster virus, which affects the ciliary body and the skin of the tip of the nose along the nasociliary nerve. Bacterial, viral, or fungal corneal ulcers are serious conditions that necessitate intense therapy and cause prolonged morbidity. Ulcers caused by Pseudomonas organisms sometimes progress to perforation in 24 to 48 hours despite intense therapy. Because any disruption of the corneal epithelium can allow entrance of organisms, infection must be considered, particularly after trauma and in the treatment of debilitated patients with a poor tear film.