A 'black cornea' secondary to topical epinephrine.

We report a case of 'black cornea" secondary to topical epinephrine therapy and present the biochemical analysis of the lesion. The formed pigment is a melanin and not the intermediate substance, adrenochrome, as has been previously reported. The pathogenesis of melanin deposition is reviewed and a hypothesis of epinephrine-melanin binding is suggested.