Quarter-Descemet membrane endothelial keratoplasty (Quarter-DMEK) for Fuchs endothelial corneal dystrophy: 6 months clinical outcome

Background/aim To assess the clinical outcome of the first series of Quarter-Descemet membrane endothelial keratoplasty (Quarter-DMEK), a potential hybrid technique between 'descemetorhexis only' and conventional, circular DMEK. Methods Prospective interventional case series at a tertiary referral centre. Twelve eyes of 12 patients with central Fuchs endothelial corneal dystrophy underwent Quarter-DMEK, that is, transplantation of one quadrant of a full-diameter DMEK graft, and were evaluated for best-corrected visual acuity (BCVA), endothelial cell density (ECD) and complications up to 6 months postoperatively. Results At 6 months postoperatively, all eyes reached a BCVA of >= 20/40 (>= 0.5), 11/12 (92%) of >= 20/25 (>= 0.8) and 6/12 (50%) of >= 20/20 (>= 1.0). Mean central ECD decreased from 2867 (+/- 161) cells/mm(2) before to 1255 (+/- 514) cells/mm(2) at 1 month, 1058 (+/- 455) cells/mm(2) at 3 months and 968 (+/- 427) cells/mm(2) at 6 months after surgery. Rebubbling was performed in 4/12 eyes (33%) within the first two months. Conclusions Quarter-DMEK may be a feasible procedure that allows for visual outcomes similar to conventional, circular DMEK. The relatively large drop in ECD within the first month may have resulted from more extensive endothelial cell migration and/or measurement error (at the graft edges). If longer-term outcomes would resemble those of conventional DMEK, Quarter-DMEK may potentially quadruple the availability of endothelial grafts.