Long-term graft survival after penetrating keratoplasty

Abstract

Purpose: To determine long-term graft survival rates and causes of secondary graft failures for a large series of penetrating keratoplasties (PKPs).

Design: Retrospective, noncomparative case series.

Participants: Longitudinal review of 3992 consecutive eyes that underwent PKP at a large tertiary care referral center from 1982 through 1996. Data were collected retrospectively from August 1982 through December 1988 and prospectively thereafter.

Intervention: Three thousand six hundred forty primary grafts and 352 regrafts.

Main outcome measures: Corneal graft survival and etiology of graft failures. Patients were evaluated preoperatively and at 1, 3, 6, 9, 12, 18, and 24 months after transplant, then at yearly intervals.

Results: Mean recipient age was 67 years (range, 1-98 years). The predominant indications for PKP were pseudophakic bullous keratopathy (32%) and Fuchs' dystrophy (23%). Graft failure occurred in 10% (385) of the eyes. The most common causes of secondary graft failure were endothelial failure (29%) or immunologic endothelial rejection (27%). Survival of first time grafts was 90% at 5 years and 82% at 10 years. Initial regrafts had significantly lower 5-year and 10-year survival rates, 53% and 41%, respectively. The highest 5-year and 10-year survival rates were noted in primary grafts for eyes with a preoperative diagnosis of keratoconus (97% and 92%, respectively), or Fuchs' dystrophy (97% and 90%, respectively). Primary grafts for aphakic bullous keratopathy without intraocular lens placement had the lowest 5-year survival rate, 70%.

Conclusions: The 5-year and 10-year survival rates in this series demonstrate that PKP is a safe and effective treatment for the corneal diseases commonly transplanted in the United States. However, endothelial failure and immunologic graft rejection were persistent risks over the long term, supporting the need for continued patient follow-up. Regrafts, aphakic eyes without intraocular lens placement at the time of transplant, and corneas with deep stromal vascularization had reduced graft survival rates. Pseudophakic bullous keratopathy grafts with a retained posterior chamber intraocular lens were at increased risk of endothelial failure compared with primary grafts done for other causes or compared with pseudophakic bullous keratopathy grafts done with intraocular lens exchange.