Abstract:
Diseases affecting the cornea are a major cause of blindness worldwide and corneal transplantation remains the primary method of visual rehabilitation in this context. Cornea transplantation is the most commonly performed transplantation procedure in New Zealand. However, no reliable data are available on the medium term outcomes of corneal transplantation in New Zealand and there is a dearth of major studies in the international literature. The aim of this research was to provide a portrait of our unique New Zealand/Aotearoa population and its experience with corneal transplantation. Specifically, data analyses were performed to measure graft survival and visual outcome following corneal transplantation, and to investigate risk factors for corneal graft failure. The New Zealand National Eye Bank records were analysed for the decade 1st January 2000 to 31st December 2009 inclusive. Detailed clinical data were obtained for a total of 941 corneal transplantation procedures; 834 penetrating keratoplasty, 73 deep anterior lamellar keratoplasty, 28 endothelial keratoplasty, and 6 patch grafts. The overall 2-year survival rate (87.9%) identified in this study was comparable to that of other survival rates reported in the literature. The two year graft survival rate was highest (95.6%) in patients with keratoconus. Six independent risk factors were found to be associated with an increased risk of graft failure on multivariate analysis; younger recipient age, preoperative best corrected visual acuity (BCVA), indication for corneal transplantation, previous contralateral graft, number of rejection episodes, and episodes of loose sutures. A BCVA of 6/12 or better was achieved by 58.7% of eyes with penetrating keratoplasty, and 69.6% achieved 6/18 or better. Visual acuity improved by 2 lines or more in 67.0% of eyes with surviving penetrating keratoplasty, with 25.1% improving by 2-4 lines, 33.8% by 5-10 lines, and 8.1% by more than 10 lines. This research, involving a total of 941 procedures, provides new knowledge and new insights into corneal transplantation in the Auckland region.