Penetrating keratoplasty for keratoconus: long-term results

PURPOSE: To study central corneal endothelial cell density and morphology and corneal topography in transplanted corneas for keratoconus 10 to 17 years postoperatively. METHODS: Retrospective, noncomparative case series including all keratoconus patients who underwent penetrating keratoplasty by one surgeon, at the same center, between January 1986 and December 1994. Seventeen patients (22 eyes) met the criteria. Four patients (5 eyes) with unchanged visual acuity during the follow-up period did not agree to return for the last follow-up examination, 1 patient (1 eye) had graft failure, and 3 patients (4 eyes) were lost to follow-up. We reviewed the charts of 9 patients (12 eyes), and collected data including manifest refraction, best corrected visual acuity (BCVA), endothelial cell density, cell morphology, and corneal topography. RESULTS: The mean follow-up period for all eyes evaluated was 13.3 +/- 2.4 years (range 10-17 years). At the last follow-up, 91.7% of eyes achieved BCVA of 20/40 or better, and mean endothelial cell density was 695 +/- 113.6 cells/mm(2). Pleomorphism was detected in 5 eyes. Keratoconus pattern, by corneal topography, was not detected in any eye at the final examination. CONCLUSION: Endothelial cell count 10-17 years post-PKP for keratoconus is very low with pleomorphism and viable grafts, indicating continued endothelial instability.