We identified 224 patients hospitalized with corneal ulcerations at the University of Michigan Hospitals, Ann Arbor, between May 1975 and September 1981, and performed a chart review on a random sample of these cases. Bimodality in the patients' age distribution was attributed to nonsurgical ocular trauma in the younger group, and predisposing keratitis, surgical trauma, bullous keratopathy, and entropion in the older group. Bacterial and postherpetic causes accounted for 52 (52%) of the sampled cases. Pseudomonas aeruginosa and Staphylococcus aureus were the major isolates. Important predisposing factors included nonsurgical and surgical trauma, herpetic keratitis, contact lens wear, corticosteroid therapy, and bullous keratopathy. Both age and visual acuity on admission had prognostic implications for improvement in visual acuity after treatment.