Corneal Graft Rejection: Incidenceand Risk Factors

Purpose: to determine the incidence and risk factors of late corneal graft rejection afterpenetrating keratoplasty (pkp).methods: records of all patients who had undergone pkp from 2002 to 2004 withoutimmunosuppressive therapy other than systemic steroids and with at least one year offollow up were reviewed. the role of possible risk factors such as demographic factors,other host factors, donor factors, indications for pkp as well as type of rejection wereevaluated.results: during the study period, 295 pkps were performed on 286 patients (176 male,110 female). mean age at the time of keratoplasty was 38±20 (range, 40 days to 90) yearsand mean follow up period was 20±10 (range 12-43) months. graft rejection occurred in94 eyes (31.8%) at an average of 7.3±6 months (range, 20 days to 39 months) after pkp.the most common type of rejection was endothelial (20.7%). corneal vascularization,regrafting, anterior synechiae, irritating sutures, active inflammation, additionalanterior segment procedures, history of trauma, uncontrolled glaucoma, prior graftrejection, recurrence of herpetic infection and eccentric grafting increased the rate ofrejection. patient age, donor size and bilateral transplantation had no significantinfluence on graft rejection.conclusion: significant risk factors for corneal graft rejection include corneal vascularization,anterior synechiae, irritating sutures, active inflammation, regrafting,additional surgery, trauma, uncontrolled intraocular pressure, history of graft rejection,recurrent herpetic infection, eccentric grafting and corneal scarring. recipient age anddonor cornea size do not seem to be risk factors for corneal graft rejection.