DMEK graft preparation techniques - liquid bubble technique compared to Melles technique.

PURPOSE: The aim of the study was to compare two Descemet membrane endothelial keratoplasty (DMEK) graft preparation techniques, the liquid bubble technique and the Melles technique. METHODS: In this prospective study, a total of 20 corneas from 10 donors were included. For each donor, one cornea was prepared using the liquid bubble technique, and the contralateral cornea using the Melles technique. Outcome measures included endothelial cell count, the occurrence of tears and defects in the graft, preparation time, and histological findings. RESULTS: Mean endothelial cell density (ECD) before preparation was 2330 ± 210 cells/mm² in the liquid bubble group (LB) and 2380 ± 157 cells/mm² in the Melles group (M). Mean ECD after preparation was 2170 ± 264 cells/mm² (LB) and 2287 ± 237 cells/mm² (M). This corresponds to an average cell loss during the preparation process of 160 ± 316,1 cells/mm² (6.87%, LB), and of 93 ± 147,1 cells/mm² (3,92%, M), which was not statistically significantly different (p = 0.05). Preparation time was statistically significantly different (p = 0.002) with a mean of 5.74 ± 2.43 min (LB) and 23.60 ± 1.81 min (M). In the liquid bubble group, collagen fibrils on the Descemet membrane after preparation were observed in 4 cases (40%), whereas in the Melles group, this was seen in only one case (10%). CONCLUSION: DMEK grafts prepared via the liquid bubble technique and via the Melles technique exhibit comparable ECD, graft quality, and surgical suitability. The liquid bubble technique offers a significant advantage in preparation time for donors without previous cataract surgery.