Vernal keratoconjunctivitis with shield ulcer--a case report.

This 9-year-old boy had a three-year history of vernal keratoconjunctivitis. A shield ulcer developed in the superior part of the cornea. The shield ulcer is a rare manifestation of the disease. Although the cause of shield ulcer is unknown, the association of shield ulcer with large papillae suggests a mechanical cause. The symptoms of itching and mucous discharge were relieved after medications with topical steroid and cromolyn sodium, but the large shield ulcer was persistent. The vernal ulcer was treated with a 72 hours collagen shield. The ulcer healed rapidly within 5 days, leaving a corneal opacity about the level of Bowman's layer.