Penetrating keratoplasty in Africa: graft survival and visual outcome.

AIM

To study the survival and visual outcome of penetrating keratoplasty in an African setting.

METHODS

A retrospective analysis of 216 corneal grafts, performed on 203 eyes of 186 patients, at Kikuyu Hospital, Kenya over a 5 year period.

RESULTS

Half of the transplants were carried out for keratoconus with only 5% of the grafts being undertaken for corneal scarring caused by trachoma or measles. The average follow up was 27.3 months. The probability of graft survival at 2 years was 87.4% (95% CI 80.6%-94.3%) for keratoconus and 64.7% (95% CI 54.8%-74.6%) for other corneal pathologies. Forty seven grafts (21.8%) in 36 patients (17.7%) are known to have become opaque. The commonest causes of graft opacification were bacterial keratitis (6.0%), endothelial failure (6.0%), and graft rejection (5.1%). Preoperatively 55% of keratoconus eyes and 75.7% of non-keratoconus eyes were blind. Postoperatively, 5% of keratoconus eyes and 41.7% of the non-keratoconus eyes were blind. Normal vision was achieved in 53.7% of operated eyes. Grafts carried out for keratoconus had a better visual outcome than grafts performed for other corneal pathologies. Preoperatively, 12.4% of keratoconus and 48.5% of non-keratoconus patients were blind in their better eye. Postoperatively, 1.1% of keratoconus patients and 25.7% of non-keratoconus patients were blind. The number of patients with normal vision in the better eye increased from 32 (17.2%) to 106 (57.0%). Sight was restored to 34 blind patients, but two patients with severe visual impairment preoperatively were blind at their last follow up. There was therefore a net reduction of 32 in the number of blind patients after 216 keratoplasties.

CONCLUSIONS

Penetrating keratoplasty can be successful in Africa, particularly for keratoconus and other corneal dystrophies. However, penetrating keratoplasty has a limited role in the treatment of blindness from corneal scarring due to trachoma, measles, and vitamin A deficiency for which community based preventive measures must remain the priority.