Histopathology of a case of epikeratophakia (aphakic epikeratoplasty).

An epikeratoplasty button was removed by penetrating keratoplasty 31 months following an aphakic epikeratoplasty. The epithelium over the donor cap was thickened with numerous surface abnormalities. Bends and fractures in the donor Bowman's membrane were found throughout the length of the specimen. A significantly decreased number of keratocytes were found in the anterior half of the donor lenticule; the posterior half of the lenticule was acellular. The interfibrillar collagen distance of the donor lenticule was significantly increased compared with that of the recipient host cornea. The central thickness of the lenticule increased the total corneal thickness by 56%. Abnormal keratocytes were found in the underlying recipient corneal stroma. Based on this study, the histopathologic features of epikeratoplasty appear to be similar to those documented in the other lamellar refractive surgical procedures of keratophakia and keratomileusis.