Purpose: To evaluate the 1-year clinical outcome after semi-circular Descemet membrane endothelial keratoplasty (hemi-DMEK) in a first case series.
Methods: In three eyes of three patients with Fuchs endothelial dystrophy, best corrected visual acuity (BCVA), endothelial cell density (ECD), pachymetry, and intra- and postoperative complications were evaluated after transplantation of a semi-circular ~12 mm diameter Descemet graft (hemi-DMEK graft).
Results: All corneas cleared within 6 months and showed a stable pachymetry thereafter (527, 535, and 490 μm, respectively). Compared to preoperative measurements, average central ECDs dropped by 51 % (56, 39, and 59 %, respectively) at 3 months, 53 % (57, 38, and 63 %, respectively) at 6 months, and 59 % (60, 47, and 71 %, respectively) at 12 months. Denuded stromal areas adjacent to the hemi-DMEK graft cleared and at 12 months peripheral ECD counts ranged from 724 to 1051 cells/mm(2). At 12 months, BCVA was 20/22 (0.9), 20/40 (0.5, amblyopic eye) and 20/17 (1.2). No postoperative complications occurred throughout the study period.
Conclusions: Hemi-DMEK may provide visual outcomes similar to those in standard DMEK at the 1-year postoperative mark. If also graft survival and complication rates prove to be similar, hemi-DMEK could become the next step in endothelial keratoplasty, owing to its potential to double the yield of transplants from the same donor pool (two hemi-DMEK grafts can be prepared from one donor cornea).
Keywords: Descemet membrane endothelial keratoplasty; Endothelial cell density; Endothelial cell migration; Fuchs endothelial dystrophy; Hemi-DMEK; Visual acuity.