Risk factors for graft failure in penetrating keratoplasty.

We clarified the preoperative risk factors for graft failure in penetrating keratoplasty with fresh donor corneas. This analysis covered 698 consecutive keratoplasty cases in a single center between 1971 and 1992, and was designed to assess the risk factors. The risk factors in penetrating keratoplasty were determined by the Cox multiple regression model which considers the follow-up periods and multiple factors simultaneously. The factors which worsen the prognosis of keratoplasty significantly were found to be preoperative endothelial dysfunction (hazard ratio = 2.3), prior glaucoma/ocular hypertension (hazard ratio = 2.0), preoperative corneal vascularization (hazard ratio for within one quadrant = 1.3, hazard ratio for 2 or more quadrants = 1.6), anterior synechiae of iris (hazard ratio = 1.5), aphakia or pseudophakia (hazard ratio = 1.4), and older donor age (hazard ratio = 1.3 in proportion to the increase of each 10-year period of age). Surgeons must take these risk factors into consideration to obtain a better prognosis for keratoplasty.