Purpose: Although several donor, recipient, and graft characteristics have been studied in relation to corneal transplantation outcomes, no study to our knowledge has assessed the impact of donor cooling times on postoperative outcomes longitudinally. With only one corneal graft available for every 70 needed worldwide, this study seeks to identify any factors that could alleviate this shortage.
Methods: Patients undergoing corneal transplantation at the Manhattan Eye, Ear & Throat Hospital over a 2-year period were retrospectively studied. Study metrics included age, diabetic history, hypertensive history, endothelial cell density, death-to-preservation time (DTP), death-to-cooling time (DTC), and time-in-preservation (TIP). Postoperative transplantation outcomes, including best corrected visual acuity (BCVA) at 6- and 12-month follow-up visits, need for re-bubbling, and need for re-grafting, were assessed. Unadjusted univariate and adjusted multivariate binary logistic regressions were performed to determine the association of cooling and preservation parameters with corneal transplantation outcomes.
Results: Among 111 transplants, our adjusted model found that DTC ≥4 hours was associated with significantly worse BCVA, but only at 6-month postoperative follow-up (odds ratio [OR]: 0.234; 95% confidence interval [CI]: 0.073-0.747; p = 0.014). By 12-month follow-up, DTC >4 hours was no longer associated with BCVA in a statistically significant manner (OR: 0.472; 95% CI: 0.135-1.653; p = 0.240). A similar trend was found at a DTC cutoff of ≥3 hours. None of the other studied parameters, including DTP, TIP, donor age, or medical history were significantly correlated with transplantation outcomes.
Conclusion: Longer DTC or DTP did not have a statistically significant effect on corneal graft outcomes after one year, though short-term outcomes were improved in donor tissues with DTC below four hours. None of the other studied variables correlated with transplantation outcomes. Given the global shortage of corneal tissue, these findings should be considered when determining suitability for transplantation.
Keywords: cooling; corneal transplant; donor; outcome; recipient; refrigeration.
© 2023 Shah et al.