Complications and graft rejection after keratoplasty: clinical outcomes and risk factors in a tertiary ophthalmology service

Abstract

Introduction. Corneal blindness is a major cause of visual impairment, and keratoplasty is often the only option to restore corneal transparency and function. Despite advances in surgical techniques, postoperative complications and graft rejection still limit long-term graft survival. This study aimed to characterise complications after keratoplasty, estimate the incidence and timing of graft rejection, and identify major clinical risk factors in a tertiary ophthalmology centre. Materials and Methods. We performed a retrospective observational study including 76 eyes of 72 patients who underwent penetrating or lamellar keratoplasty at the Ophthalmic Surgery Centre Ovisus, Chișinău, between 2019 and 2024. Demographic data, indication for keratoplasty, surgical technique, pre-existing ocular status, postoperative course and clinical signs of rejection were extracted from medical records. Best corrected visual acuity (BCVA), graft transparency, postoperative complications and episodes of rejection were analysed. Associations between potential risk factors and rejection were assessed using odds ratios (OR) with 95% confidence intervals (95% CI) in univariate and multivariate models, with statistical significance set at p < 0.05. Results. Mean age at surgery was 52.6 ± 14.3 years; 56.9% of patients were male. The main indications were corneal dystrophies (28.9%), ectatic disease including keratoconus (23.7%), post-infectious corneal scars (19.7%) and postsurgical endothelial decompensation (17.1%). Lamellar keratoplasty was performed in 57.9% of eyes (DALK 21.1%, DSAEK 19.7%, DMEK 17.1%), while 42.1% underwent penetrating keratoplasty. At least one postoperative complication occurred in 44.7% of eyes; early events (25.0%) were mainly transient corneal oedema (15.8%), suture-related problems (11.8%), infectious keratitis (3.9%) and ocular hypertension (9.2%). Graft rejection was documented in 18.4% of eyes (14/76), more frequently after penetrating than lamellar keratoplasty (25.0% vs 13.6%). Independent predictors of rejection were postoperative inflammatory or infectious episodes (adjusted OR 4.92; 95% CI 1.48–16.31) and non-adherence or premature tapering of topical corticosteroids (adjusted OR 4.21; 95% CI 1.19–14.87). Conclusions. Keratoplasty provides meaningful visual rehabilitation, but nearly half of grafts experience postoperative complications and almost one fifth develop rejection. Careful preoperative risk assessment, strict control of postoperative inflammation and infection, and reinforcement of adherence to corticosteroid therapy are essential to improve long-term graft survival and visual outcomes.