Preparation and outcome of swollen versus dextran deswollen grafts in descemet membrane endothelial keratoplasty (DMEK)

Abstract

Aims/Purpose: To evaluate the influence of organ culture medium containing dextran on graft characteristics during preparation as well as the outcome of subsequent Descemet Membrane Endothelial Keratoplasty (DMEK).Methods: 31 corneoscleral rims of the Eye Bank of the University Hospital of Cologne with a donor age between 52 and 74 years were examined between 2018 and 2022 for their intraoperative preparation conditions and the outcome after performing 31 DMEKs. For this purpose, corneoscleral rims were randomized into two organ‐cultured groups, one immersed in culture medium with dextran (group A, n = 16) and the other in medium without dextran (group B, n = 15). The intraoperative graft preparation conditions were noted by using a standardized scoresheet, including splitting and stripping behaviour, central and peripheral attachment as well as graft fragility. The post‐operative outcome parameters were defined as Best Spectacle‐Corrected Visual Acuity (BSCVA), central and peripheral corneal thickness (CCT and PCT), endothelial cell count (ECC) and re‐bubbling rate.Results: In both groups, all 31 DM‐endothelium grafts were usable for DMEK. There was no significant difference in the intraoperative preparation conditions of swollen versus dextran deswollen DM‐endothelium grafts in respect to stripping (p = 0.722) and to Descemet membrane splitting behaviour (p = 0.013). The fragility of the grafts showed no significant difference (p = 0.433), as well as the peripheral scars indicating a pseudophakic donor (p = 1.000) and the tendency for central tearing (p = 0.484) during preparation. No significant difference in the outcome 12 months after DMEK in conditions of swollen versus dextran deswollen DM‐endothelium grafts regrading CCT (p = 0.189), re‐bubbling (p = 0.704), PCT (p = 0.063), could be observed. BSCVA was significantly better in group B 12 months after DMEK with p = 0.032 (group A 0.08 ± 0.38: group B 0.03 ± 0.13).Conclusions: This pilot study does not show relevant and significant differences between swollen versus dextran deswollen grafts in DMEK transplantation. Future prospective studies with higher patient numbers are needed. Our study suggests also non‐deswollen donors as suitable for DMEK surgery.