Impact of donor tissue diameter on postoperative central endothelial cell density in Descemet Membrane Endothelial Keratoplasty.

Abstract

To assess the effect of donor tissue diameter in Descemet Membrane Endothelial Keratoplasty (DMEK) on postoperative endothelial cell density (ECD) mainly in Fuchs Endothelial Corneal Dystrophy (FECD) patients. Retrospective review of 693 consecutive DMEK surgeries from the prospective Cologne DMEK database performed between 07/2011 and 07/2016 at the Department of Ophthalmology, University of Cologne. Eight- versus ten-millimetre large donor DMEK grafts of two different surgeons using identical surgical techniques were compared. A total of 693 consecutive DMEK surgeries were included. Two groups (8 versus 10mm DMEK graft diameter) were compared: 23% of eyes received 8-mm grafts (group 1, n=160) and 77% 10-mm grafts (group 2, n=533). Mean preoperative ECD (±SD) of donor tissue was 2736±224 cells/mm2 in group 1 and 2714±232 in group 2. Group 1 showed a mean ECD of 1740±439 cells/mm2 (mean±SD; n=67) 12months after DMEK compared to 1664±404 cells/mm2 (mean±SD; n=344) in group 2. The difference between the 6- and 12-month ECD of both groups was not significant (p=0.675; p=0.161). Total decrease in ECD 6- and 12-months postoperatively was 38±14 (n=128) and 36±16% in group 1 (n=66) versus 37±15% (n=398) and 38±15% in group 2 (n=342; p=0.414; p=0.198, respectively). Our data suggest that postoperative central endothelial cell density is not significantly associated with DMEK graft diameters in the range of 8-10mm in cases with healthy peripheral host endothelium (such as FECD).