Punching a Graft for Descemet Membrane Endothelial Keratoplasty Onto a Contact Lens Reduces Endothelial Cell Loss at the Graft's Margin.

PURPOSE: To evaluate whether punching Descemet membrane endothelial keratoplasty (DMEK) corneal grafts onto a contact lens scaffold reduces endothelial cell loss at the graft margin in comparison to punching the graft directly onto the donor stroma. METHODS: DMEK grafts were prepared using 2 different methods after peeling the graft from the stroma: punching onto a contact lens and punching onto the donor stroma. The grafts were then evaluated for the width of Descemet membrane devoid of endothelial cells in the peripheral ring, measured at 4 points at the graft margin. RESULTS: Our study included 6 grafts, harvested from 3 donors aged 66.3 ± 5.1 years. Grafts prepared on a contact lens scaffolding had more of their Descemet membrane margin populated by endothelial cells than did grafts that were punched directly onto the donor stroma (total denuded area: 0.06 ± 0.08 mm vs. 1.17 ± 0.02 mm, P = 0.018; maximal width of denuded area: 59.6 ± 28.4 µm vs. 100.2 ± 59.7 µm, P = 0.07). Donor grafts on contact lens had approximately 2.5% more endothelial cells available for transplantation (2425 cells/mm vs. 2367 cells/mm). Graft preparation time did not significantly differ between the methods (6.4 ± 0.49 vs. 9.8 ± 3.7 minutes, P = 0.46). CONCLUSIONS: Punching DMEK grafts onto a contact lens reduces endothelial loss at the grafts' margins and may prolong their survival.