Epithelial cyst of the iris following penetrating keratoplasty.

In a 35-year-old patient with keratoconus a cyst of the iris was first observed 22 months after routine penetrating keratoplasty. The lesion was completely excised and shown by light and transmission electron microscopy to be composed of conjunctival epithelium organised as a single large cyst containing serous material and occasional free epithelial cells. The management of epithelial implantation cysts is discussed. When indicated, complete surgical excision without ruputure is preferred to avoid possible intraocular dissemination of viable epithelial cells that might result in further complications.