Air-assisted donor preparation for DMEK

Air-assisted donor preparation for DMEK Venzano al. have described a technique of Descemet membrane air-bubble separation. We also use an air-assisted (reverse big bubble) technique to prepare Descemet membrane for Descemet membrane endothelial keratoplasty. In our method, a corneoscleral button is placed endothelial side up on a Barron donor punch and fixed by grasping the outer scleral edge with a 0.12 forceps. A 27-gauge bevel-up needle attached to a 2 mL syringe filled with air is inserted into the posterior stroma with the entry point located just outside Schwalbe line. The needle is advanced to the central cornea. Air is gently injected to make a big bubble, detaching Descemet membrane from the posterior stroma. Injecting into the endothelial side-up corneoscleral button allows us better visualization and makes the procedure more feasible, less instrument dependent, and less traumatic. Venzano et al. reported a high success rate of Descemet membrane detachment with their method. This high rate of success might be related to the older age (mean Z 78 years) of donors. In our experience, we found that air-assisted Descemet membrane dissection is more difficult in young patients (younger than 40 years) and attempts to make a complete detachment may lead to Descemet membrane rupture. In our first 10 cases, with a mean age of 32 years, an incomplete detachment (smaller than 8.0 mm diameter) occurred in 2 cases and Descemet membrane rupture occurred in 1 case. We now prefer older donors with higher endothelial cell counts for this technique.