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

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.

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.

Mean ECD was significantly higher in the DMEK-pD group at all postoperative time points: 2368 ± 224 versus 2024 ± 312 cells/mm2 at 6 months, 1942 ± 284 versus 1698 ± 352 cells/mm2 at 2 years, and 1534 ± 279 versus 1280 ± 394 cells/mm2 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).

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.