Objective: To determine the survival rates and causes of secondary graft failure in a large, consecutive series of penetrating keratoplasties.
Design: All eyes undergoing penetrating keratoplasty at a single center were evaluated for factors relating to penetrating keratoplasty preoperatively, surgically, and postoperatively at 1, 3, 6, 9, 12, 18, and 24 months and then at yearly intervals. Since 1986, data analysis has been prospective.
Setting: A large, private practice, tertiary center for corneal disorders and surgery.
Patients: A consecutive series of 1819 penetrating keratoplasties performed from August 1982 through August 1990; 13 eyes with primary graft failure were excluded.
Main outcome measure: Graft failure and causes of failure. Follow-up ranged from 1 to 96 months, with a mean of 26.6 months.
Results: Pseudophakic bullous keratopathy was the most common diagnosis necessitating keratoplasty (38.6%). Secondary failures occurred 111 times (6.1%). The 2- and 5-year survival rates for all grafts in the study were 95% and 91%, respectively. While endothelial failure as a result of immunologic allograft reactions was the most common cause of graft failure (27%), problems with the external surface of the graft caused nearly as many failures (25%). The risk of failure from surface-related problems was highest at 3 months after surgery. There were significantly decreased survival rates for grafts in eyes with regrafts (P < .0001), in eyes left aphakic at keratoplasty (P < .0001), and in eyes with deep stromal vascularization (P < .0001).
Conclusion: Penetrating keratoplasty is a successful form of transplantation, and survival rates are gradually increasing. The risk of graft failure appears highest within the first year after transplantation.