To describe a further modification of Descemet membrane endothelial keratoplasty (DMEK), using a quarter of an untrephined full-size donor Descemet membrane (DM) sheet (“Quarter-DMEK”).
A 58-year-old patient underwent Quarter-DMEK for Fuchs endothelial dystrophy in his pseudophakic right eye, with a single quadrant of a full-size, 11.5-mm-diameter DM graft.
Best-corrected visual acuity improved from 20/50 (0.4) before surgery to 20/40 (0.5) at 1 day, 20/30 (0.7) at 1 week, 20/25 (0.8) at 1 month and 20/20 (1.0) at 3 months after surgery. Central endothelial cell density decreased from 2700 cells/mm2 before surgery to 1551 cells/mm2 at 1 week, 1104 cells/mm2 at 1 month, and 846 cells/mm2 at 3 months after surgery. Pachymetry returned to normal values within the first month. No complications were observed.
Quarter-DMEK may give fast visual rehabilitation within the first month similar to visual outcomes after circular DMEK or semicircular DMEK (hemi-DMEK). If long-term endothelial cell density would prove acceptable in a larger number of cases, quarter-DMEK may have the potential to quadruple the availability of donor endothelial tissue for endothelial keratoplasty.