Minimizing graft preparation failure in descemet membrane endothelial keratoplasty

Purpose: To report the failure rate of 2 graft preparation techniques for Descemet membrane endothelial keratoplasty (DMEK) and to evaluate how to minimize graft preparation failure. Methods: Retrospective, nonrandomized study at an eye bank specialized in graft preparation for lamellar keratoplasty. For 1416 donor corneas, the DMEK graft preparation failure rate was evaluated for 2 different techniques, technique I: "Standardized traditional technique" (n = 341) and technique II: "Standardized notouch technique" (n = 933), and for grafts that were converted from technique II to technique I during preparation (n = 142). Results: The overall failure rate averaged 3.9% (55/1416): 7.0% (24/ 341) for technique I and 2.9% (31/1075) for technique II (P , 0.05). Tissue preparations which were converted from technique II to technique I failed in 13.4% (19/142), whereas for grafts that were entirely prepared by technique II, the failure rate was only 1.3% (12/933). The endothelial cell density decrease (before compared with after preparation) did not differ for both techniques (1.1% vs. 0.2%, P . 0.05). Conclusions: Various DMEK graft preparation techniques may provide failure rates of ,4%. A "no-touch preparation" approach (technique II) may combine good graft quality (completely intact endothelial cell layer, ie, negligible preparation-induced endothelial cell density decrease) with low risk of dissection failure, leaving the possibility of conversion to "traditional preparation" (technique I) as a backup method.