BUB ‘N’ ROLL TECHNIQUE A novel approach to harvesting the Descemet-endothelium complex in DMEK surgery

BUB ‘N’ ROLL TECHNIQUE A novel approach to harvesting the Descemet-endothelium complex in DMEK surgery Background: Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal transplantation, often treated with Descemet membrane endothelial keratoplasty (DMEK). Current DMEK techniques require precise harvesting of the Descemet membrane and endothelium complex, and this step can be technically challenging. This study investigates a novel, simplified technique called "Bub 'n' Roll" for preparing donor tissue for DMEK, with the goal of improving reproducibility and minimizing endothelial cell loss. Methods and Materials: Forty-one corneal tissues were prepared using the Bub 'n' Roll technique. This hydrodissection method involves injecting a preservation fluid to create a Type 1 or Type 2 bubble, facilitating separation and spontaneous rolling of the Descemet membrane and endothelium. Surgical dissection time, endothelial cell density (ECD) of the harvested tissue, and post-operative outcomes (rebubbling rates, best corrected visual acuity (BCVA), and central corneal thickness (CCT)) were retrospectively analyzed. Tissues were preserved in EUSOL-C (Alchemy) cold storage fluid at +4°C until the endothelial descemetic 'roll' was set up and then in TISSUE-C (Alchemy) until the DMEK transplantation surgical procedure. The procedure is performed bimanually under an optical biomicroscope at 10x magnification. Results: The study included 41 patients (61% female, mean age 69.2 years). Average donor age was 63.3 years (51% female). Average surgical duration was 318.62 ± 69.94 seconds for Type 1 bubbles and 377 ± 63.95 for Type 2 (p=0.0237). Rebubbling was necessary in 24% and 25% of cases. The Cellular Density significantly reduced over time after Bub'n'roll (p < 0.001). At 3 months the 1 type lost 30.2 + 6% of endothelial cells, at 24 months lost 40 +- 4.5 % compared with the type 2 bubbles 19 +-5% at 3 months and a 33 +-3% at 24 months .There was a correlation between duration and loss of endothelial cells in type 1. At the last follow-up, the average BVCA was 0.17 ± 0.07 with significance (p< 0.001). Conclusion: The Bub 'n' Roll technique appears to offer a viable and simplified approach to DMEK donor tissue preparation. The technique reduces intraoperative manipulation, is readily reproducible and allows excellent control of surgical steps. However, limitations of this single-surgeon, retrospective study include a relatively small sample size and limited follow-up. Further multi-center, longer-term, and controlled studies are warranted to determine the long-term efficacy and benefits of this technique in a broader surgical community and compare its advantages against existing methods.