Ocular Surface Squamous Neoplasia Masquerading as Recalcitrant Epithelial Keratitis

The purpose of this study was to report a unique case of ocular surface squamous neoplasia that masqueraded as a nonresolving toxic epithelial keratitis.

This was a case report and review of the literature.

A 79-year-old man presented with decreased vision, redness, and a foreign body sensation in his right eye that was refractory to treatment with lubrication and topical nonsteroidal antiinflammatory drops. Before presentation, the referring provider believed that he had medicamentosa-related keratitis and placed him on oral methazolamide. Slitlamp biomicroscopy of the right eye revealed diffuse epitheliopathy with punctate fluorescein staining and subtle underlying corneal epithelial opalescence. A mildly thickened and inflamed pinguecula was noted from 2 to 5 o'clock at the limbus of the right eye. An anterior segment high-resolution optical coherence tomography revealed thickened, hyperreflective epithelium with an abrupt transition. An incisional biopsy confirmed conjunctival and corneal intraepithelial neoplasia. The patient improved after 4 cycles of topical chemotherapy with 1% 5-fluorouracil eye drops with complete resolution of the corneal and conjunctival pathology.

Ocular surface squamous neoplasia can rarely masquerade as a recalcitrant medicamentosa and epithelial keratitis. In subtle cases or in cases with combined ocular surface morbidities, anterior segment high-resolution optical coherence tomography can be helpful to diagnose and direct therapy.