Transconjunctival elimination of keratin from an intratarsal meibomian cyst.

An unusual example of an intratarsal meibomian keratinous cyst is described in a 69-year-old man with spontaneous transepithelial (conjunctival) elimination. The lesion created an externally visible lump in the eyelid, which on eversion was found to be accompanied by yellow-whitish protruding material with a surrounding circular mound of reactive tissue. Excision revealed a large mass and smaller fragments of anuclear keratin (trichilemmal-type) embedded and sequestered in fibrous tissue with a granulomatous response. A re-excision was required because of persistent and irritating keratinous material, contrasting with the more indolent course of an uncomplicated epidermoid cyst of the eyelid dermis. This is the first documented instance of spontaneous rupture and extrusion of a meibomian tarsal cyst's keratin contents.