Dmek Preparation On Tissues Following Hypothermic Storage In Two New Storage Liquids

The purpose of this study was to assess the suitability of two new hypothermic corneal storage media from AL.CHI.MI.A. S.r.l. for preparing Descemet’s Membrane Endothelial Keratoplasty (DMEK) grafts.

Prospective study on human donor corneas unsuitable for transplantation for research purposes at the Fondazione Banca degli Occhi del Veneto (FBOV).

30 human donor corneas were stored in four different media: A and B (AL.CHI.MI.A. Srl, n=10 each) at 2-8°C for up to 14 days, and standard organ culture medium followed by deswelling medium (n=10, controls) at 31°C for up to 14 days. DMEK grafts were prepared using mechanical stripping technique with specific surgical instruments for DMEK (Moria, France) after 5 to 14 days of storage at 2-8°C or 31-35°C (controls only). Endothelial mortality was evaluated before and after DMEK preparation using fluorescence microscopy after Calcein-AM staining and digital image analysis. The time and ease of DMEK graft preparation were assessed using a grading scale from 0 to 3 (0= not executable, 1= difficult, 2= executable, 3= easy).

Endo-out DMEK graft were successfully obtained using the mechanical stripping technique in all three media groups. Similar time of preparation,  % of EC mortality increase after DMEK graft preparation and ease of DMEK graft preparation were observed in all three media groups. Groups A and B did not need an additional corneal deswelling phase of 48h after organculture prior to DMEK graft preparation which was necessary for the control group.

Naturally rolled DMEK endo-out grafts were successfully prepared using mechanical stripping technique on human corneal tissues stored in the new A and B media at at 2-8°C for up to 14 days with optimal preservation of corneal quality. Furthermore, the new media facilitated DMEK graft preparation compared to control organculture and deswelling media, as deswelling phase was not required before DMEK processing.