ABSTRACT
PURPOSE: Contact lens-induced peripheral ulcer (CLPU), a sudden-onset adverse event observed with extended wear of hydrogel lenses, is characterized by a single, small, circular, focal anterior stromal infiltrate in the corneal periphery or midperiphery. The condition is always associated with a significant overlying epithelial loss and resolves in a scar. The aim was to determine, by using histopathologic techniques, the nature and type of the corneal infiltrate of these events. METHODS: Three CLPUs observed in three patients using disposable hydrogel lenses on an extended-wear schedule were examined. The eye was topically anesthetized, and a corneal section including all of the infiltrate was taken. A small triangular piece of conjunctiva immediately adjacent to the infiltrate was sectioned. The tissue was immediately fixed, processed, stained using hematoxylin and eosin and periodic acid-Schiff stains, and examined by using light microscopy. RESULTS: The diameter of these three corneal infiltrates varied from 0.3 to 0.6 mm. Histopathology of the corneal sections revealed a focal epithelial loss corresponding to the infiltrated stroma in all three patients. The adjacent epithelium was thinned. Bowman's layer was intact in two patients and had a localized area of loss in the remaining patient. The anterior stroma was densely infiltrated with polymorphonuclear leukocytes and had focal areas of necrosis. The infiltration was most dense in the region immediately underlying Bowman's layer. No other infiltrative cell type was seen in any of the sections. Histopathology of the conjunctiva revealed features consistent with normal conjunctival tissue. CONCLUSIONS: On histopathology of CLPU, distinctive features (i.e., focal corneal epithelial loss, an intact Bowman's membrane, and a localized infiltration of the anterior stroma with polymorphonuclear leukocytes) were seen. These features suggest that the event is an acute inflammatory process and probably noninfective in nature.
