Visual and ultrastructural analysis after splitting of recipient's Descemet membrane during Descemet membrane endothelial keratoplasty.

BACKGROUND

During Descemetorhexis in Descemet Membrane Endothelial Keratoplasty (DMEK), inadvertent lamellar splitting of the recipient's Descemet membrane (DM) may occur, leaving DM remnants on the posterior corneal surface. This study investigates the influence of lamellar splitting on surgical outcome as well as the histological ultrastructure of split DMs.

METHODS

In this prospective, observational, single-centre cohort study 129 eyes of 102 patients were divided into two groups depending on the occurrence of intraoperative splitting. If splitting of the recipient's DM occurred, the remnants were polished via irrigation/aspiration. The primary outcome was the corrected distance visual acuity (CDVA) four months after DMEK. Secondary outcomes were central corneal thickness (CCT), thinnest corneal thickness (TCT), posterior corneal density (PCD), endothelial cell loss (ECL), and the re-bubbling rate. For histopathological analysis two removed DMs were examined using scanning and transmission electron microscopy.

RESULTS

Intraoperative splitting occurred in 36 eyes (27.9%). The postoperative CDVA in the group with splitting (0.12 ± 0.12 logMAR) did not significantly differ from the group without splitting (0.12 ± 0.12 logMAR; p = 0.96). CCT, TCT, PCD, ECL, and the re-bubbling rate also did not significantly differ between both groups (p > 0.05). In ultrastructural analysis, the split layer had a thickness of 2 µm and showed an irregular splitting interface.

CONCLUSION

Inadvertent lamellar splitting of the recipient's DM during DMEK does not have a significant impact on the visual outcome. Therefore, polishing the DM remnants intraoperatively may address this complication in sufficient manner for optimizing visual outcomes.