Yogurt Technique for Descemet Membrane Endothelial Keratoplasty Graft Preparation: Early Clinical Outcomes

Purpose: The aim of this study was to evaluate the efficacy and safety of the Yogurt technique for Descemet membrane endothelial keratoplasty (DMEK) graft preparation. Methods: This study included patients who underwent DMEK combined or not with phacoemulsification surgery using donor tissues prepared by a surgeon with the DMEK Tzamalis disposable punch at 2 referral hospitals between October 2019 and June 2021. Primary outcomes were duration of graft preparation, surgeon grading of graft quality, and endothelial cell density measured at 1 and 6 months after surgery. Secondary outcomes were best-corrected visual acuity (BCVA) measured at 1 and 6 months postoperatively and DMEK intraoperative and postoperative complications. Results: Forty-nine patients were included in this study. The mean DMEK graft preparation time was 7.2 ± 1.4 minutes. Donor grafts were rated good in 67.3% of cases (33 of 49), sufficient in 24.5% (12 of 49), and poor in 8.2% (4 of 49). Donor mean endothelial cell density was 2580 ± 155 preoperatively, which were reduced to 2269 ± 191 ( P < 0.000) and 1697 ± 142 ( P < 0.0001) at 1 and 6 months, respectively. No significant difference was found in graft preparation outcome ( P = 0.543). The preoperative BCVA was 0.65 ± 0.44 logMAR, which improved to 0.31 ± 0.43 logMAR ( P < 0.0001) and 0.12 ± 0.14 logMAR ( P < 0.0001) at 1 and 6 months after surgery, respectively. Conclusions: This study shows that the DMEK Tzamalis punch can be used as an effective and safe method for DMEK graft preparation with a shallow learning curve that allows it to be successfully performed by relatively inexperienced surgeons.