Abstract
Abstract: :
Purpose: To present a series of patients who developed recurrent ectasia in corneal grafts performed for keratoconus, and to review the outcomes of patients who were re–grafted for recurrent ectasia. Methods: The records of patients of the University of Michigan Kellogg Eye Center who had recurrent ectasia after penetrating keratoplasty for keratoconus were retrospectively reviewed by study ophthalmologists. Results: Twenty–nine eyes of 20 patients were identified with recurrent ectasia in penetrating keratoplasties performed for keratoconus. Eleven patients were male, and 18 patients had bilateral penetrating keratoplasty performed. For the ectatic grafts, age at penetrating keratoplasty was 32.5 ± 6.4 years (mean ± SD, range 22–49 years), pre–operative average keratometry was >60 D in 13 eyes, 55–60 D in 4 eyes, and unknown in 12 eyes. Mean donor size was 8.5 mm (range, 7.0–9.0 mm), and suturing techniques included interrupted only, running only, or a combination. Recurrent ectasia developed 21.4 ± 7.3 years after penetrating keratoplasty (range, 5–36 years, n=29). Astigmatism increased by 4.8 ± 5.3 D (n=22) from the time all sutures were removed to development of recurrent ectasia. Ectasia was often preceded by thinning and typically occurred at the inferior graft–host junction. Ten eyes of 8 patients required a second penetrating keratoplasty (re–graft) for recurrent ectasia to improve vision or contact lens tolerance. Histopathology of the excised grafts revealed changes consistent with keratoconus. Seven of the 10 re–grafts (6 patients) were doing well at last follow–up (6.0 ± 5.5 years, range, 6 months to 15 years), 1 re–graft failed after 7 years (graft rejection), and 2 re–grafts (1 patient) developed ectasia again after 19 and 21 years, the latter requiring a third penetrating keratoplasty to improve vision. Conclusions:This is the largest series of patients with recurrent ectasia in corneal grafts performed for keratoconus. Recurrent ectasia in grafts typically develops after two decades, occurs at the graft–host junction, and histopathology shows changes consistent with keratoconus within the excised button. Recurrent ectasia is frequently bilateral and can recur after re–grafting, suggesting host factors are responsible for the disorder.
Keywords: keratoconus • cornea: clinical science • transplantation