Long-term outcomes of corneal transplantation: a review of 8,378 patients

Purpose: To analyze the outcomes of corneal transplantation procedures over a 13-year period at Farabi Eye Hospital, Tehran, Iran, to identify trends and determinants influencing the frequency and success of primary and re-transplantations. Methods: Utilizing a comprehensive dataset from the hospital’s Hospital Information System, the study reviewed the records of 8,378 patients who underwent corneal transplants between 2009 and 2022. This analysis included demographic information, surgical details, and follow-up data. Statistical methods were applied to assess the impact of variables such as age, gender, surgeon experience, and surgical techniques on the likelihood of re-transplantation. Results: Of the 8,378 transplants, 7,660 (91.4%) were primary procedures while 718 (8.6%) involved re-transplantation. The most common primary transplant was penetrating keratoplasty (PKP, 50.3%), followed by Descemet’s stripping endothelial keratoplasty (DSAEK, 29.3%), and deep anterior lamellar keratoplasty (DALK, 18.5%). Analysis revealed no significant association between re-transplantation rates and patient gender or nationality. Older recipient age correlates with higher re-transplantation rates, likely due to reduced regenerative capacity and increased comorbidities in older patients. Pre-transplant comorbidities (e.g., keratoconus, ulcers), concurrent surgeries (e.g., vitrectomy), and prior procedures (e.g., glaucoma surgeries, IOL implantation) significantly increase re-transplantation risk, likely due to additional ocular stress and inflammation. Conclusion: The study highlights the importance of patient age, surgeon experience, and the choice of surgical technique in the success rates of corneal transplants. These factors are crucial for optimizing patient outcomes and minimizing the necessity for re-transplantations.