THE AUSTRALIAN-CORNEAL-GRAFT-REGISTRY - 1990 TO 1992 REPORT

The aims of the Australian Corneal Graft Registry are to collect and c ollate statistical information on the practice of corneal transplantat ion around Australia, to identify risk factors for corneal graft failu re, and to provide information on graft and visual outcome. The curren t report encompasses analyses performed on 3608 corneal grafts (96% pe netrating and 4% lamellar) entered into the Registry between May 1985 and July 1991. Sixty-four per cent of grafts have undergone one or mor e rounds of follow-up by the 189 contributing surgeons and 110 additio nal referring practitioners: five-year Kaplan-Meier graft survival for penetrating and lamellar grafts is 72% and 84%, respectively. The mai n indications for penetrating keratoplasty were keratoconus (31%), bul lous keratopathy (25%), history of failed previous graft (14%), cornea l scars and opacities (11%), and corneal dystrophies (7%). The most co mmon reasons listed for failure of penetrating grafts were rejection ( 33%), glaucoma (11%), non-viral infections (10%), endothelial cell fai lure (8%) and herpetic infection (7%). In 19% of cases, the reason for graft failure was unclear. The main indications for lamellar keratopl asty were pterygium (32%), thinning, necrosis or ulceration from old b eta-radiation therapy for pterygium (17%), and scleral ulcers, necrosi s, ectasia, perforations or melts (29%). The most common reasons for t he failure of lamellar grafts were corneal melting (43%) and sloughing of the graft (29%). Among the factors that influenced the survival of penetrating corneal grafts to a significant extent (P<0.05) in univar iate analysis were: the centre effect, indication for graft, graft num ber, a history of pregnancy or blood transfusion, inflammation before or at the time of graft, corneal vascularisation at the time of graft, a history of raised intraocular pressure, the donor cornea procuremen t source, the death to donor cornea enucleation time, graft size and l arge degrees of oversizing, lens status and the type of intraocular le ns in situ. In the postoperative period, risk factors for failure incl uded early removal of graft sutures, neovascularisation of the graft, herpetic recurrences in the graft and the occurrence of rejection epis odes. The variables that best predicted penetrating corneal graft fail ure in Cox proportional hazards regression analysis were aphakia or th e presence of an anterior chamber or iris-clip intraocular lens, very small or very large grafts, a history of previous ipsilateral graft, a n indication for graft that was neither keratoconus nor any of the cor neal dystrophies, inflammation at the time of graft, and a postoperati ve rise in intraocular pressure. Among the factors without significant effect on penetrating corneal graft outcome were donor age, donor cor nea storage medium and whether the graft was performed as a triple or staged procedure. Considering all grafts at the time of most recent fo llow-up, 47% of eyes with penetrating grafts achieved a best-corrected Snellen acuity of 6/12, compared with 56% of all eyes with lamellar g rafts. In 70% of eyes with penetrating grafts, vision was corrected wi th spectacles (28%), a contact lens (6%), an intraocular lens (18%) or a combination of one or more devices (18%). Nineteen per cent of the cohort of penetrating grafts with follow-up had five or more dioptres of irregular astigmatism in the grafted eye and 20% had one or more fa ctors, unrelated to the graft, which nonetheless affected visual acuit y.