Five-Year Endothelial Cell Density Outcomes After DMEK Using Peripherally Versus Centrally Trephinated Donor Tissue

Purpose: To compare 5-year endothelial cell density (ECD) outcomes after Descemet membrane endothelial keratoplasty (DMEK) using peripherally trephinated donor tissue (DMEK-pD) versus centrally trephinated donor tissue (DMEK-cD) in eyes with corneal endothelial dysfunction of various etiologies. Methods: This retrospective comparative nonrandomized interventional cohort study included 428 eyes of 383 patients who underwent DMEK-pD (n = 205) or DMEK-cD (n = 223), with assignment based on surgeon preference, performed either alone or combined with cataract surgery using a standardized no-touch technique. All grafts were surgeon-prepared intraoperatively. ECD was measured at 6 months and annually up to 5 years. Corrected distance visual acuity, postoperative complications, and secondary graft failure (SGF) were recorded. Comparative and subgroup analyses were performed according to underlying diagnosis. Results: Mean ECD was significantly higher in the DMEK-pD group at all postoperative time points: 2368 ± 224 versus 2024 ± 312 cells/mm 2 at 6 months, 1942 ± 284 versus 1698 ± 352 cells/mm 2 at 2 years, and 1534 ± 279 versus 1280 ± 394 cells/mm 2 at 5 years (all P < 0.001). Visual acuity improvement was comparable between groups ( P = 0.15). Subgroup analysis demonstrated the greatest long-term ECD preservation in eyes with Fuchs endothelial corneal dystrophy undergoing DMEK-pD ( P < 0.001). Postoperative complication rates were similar in both groups. SGF occurred more frequently in DMEK-cD (10.8%) than DMEK-pD (5.9%), although the difference was not statistically significant ( P = 0.13). Conclusions: DMEK using DMEK-pD demonstrates sustained long-term ECD advantages over centrally trephinated DMEK in heterogeneous endothelial diseases, without compromising visual outcomes or safety. This suggests that a simple donor preparation modification may enhance graft longevity without altering surgical technique.