Hemi-Descemet membrane endothelial keratoplasty transplantation: a potential method for increasing the pool of endothelial graft tissue.

IMPORTANCE This study evaluates the technical feasibility and clinical outcomes of a Descemet membrane endothelial keratoplasty (DMEK) technique that could increase the availability of donor tissue for DMEK. OBJECTIVE To evaluate the clinical outcome of using a semicircular, large-diameter Descemet membrane graft in DMEK (hemi-DMEK), potentially allowing the use of a single donor cornea for 2 DMEK procedures. DESIGN, SETTING, AND PARTICIPANTS A prospective, interventional case series was conducted at a tertiary referral center. Three eyes of 3 patients with Fuchs endothelial dystrophy received a hemi-DMEK. INTERVENTION Transplantation of a semicircular, large-diameter hemi-DMEK graft. MAIN OUTCOMES AND MEASURES Best-corrected visual acuity, endothelial cell density, pachymetry, and intraoperative and postoperative complications. RESULTS The patients' best-corrected visual acuity at 6 months was 0.70 (Snellen equivalent, 20/29), 0.50 (20/40 [amblyopic eye]), and 1.20 (20/17). At 1 month, endothelial cell density decreased by 49%, 31%, and 39%, respectively, and endothelial cell migration appeared to continue for up to 6 months. Central corneal thicknesses decreased from 682, 707, and 681 μm before surgery to 523, 534, and 489 μm, respectively, at 6 months. No intraoperative or postoperative complications were seen. CONCLUSIONS AND RELEVANCE Hemi-DMEK (using half-moon-shaped grafts) is technically feasible and may provide visual outcomes similar to those obtained with routine DMEK (full-moon-shaped graft). If so, this technique may have the potential to double the availability of donor endothelial tissue for DMEK surgery.