*Correspondence, Lana Fu: L.Fu@nhs.net

Objective To analyse risk factors and long-term outcomes after rebubbling and graft detachment in Descemet membrane endothelial keratoplasty (DMEK).

Methods and Analysis 176 consecutive DMEK grafts of 125 patients performed by 8 surgeons with a standardised technique between January 2015 and January 2022 were analysed. Main outcome measures were graft detachments, rebubbling rate, postoperative outcomes, and risk factors for graft failure and rebubbling.

Results 6 (3.4%) grafts required rebubbling (<1/3 detached). 41 (23%) grafts developed self-resolving partial detachments (<1/3detached). 5-year graft survival were 96%, 87%, and 83% in fully attached, partially detached and rebubbled eyes. Mean best spectacle corrected visual acuity (BSCVA) at last follow-up were 0.00±0.34, 0.14±0.25, and 0.18±0.19 logMAR (p=0.266) in fully attached, partially detached and rebubbled eyes. Percentage endothelial cell loss (ECL) was 57.5±14.1, 57.9±14.2, and 68.8±8.8 (p=0.035) in fully attached, partially detached and rebubbled eyes. Graft failure occurred in 9 (5.1%) eyes: 3 grafts had primary failure, 2 had early failure (<3 months), 2 had late failure (<12 months), and 2 grafts did not fully unfold intraoperatively. Intraoperative trauma (score) was a risk factor for graft failure (HR 1.81; 95% CI: 1.33 – 2.50 (p=0.0229)). Indication for surgery was a risk factor for rebubbling (HR 5.28; 95% CI: 5.11 – 72.4 (p=0.00703)).

Conclusion DMEK grafts had better graft survival if there was no partial detachment or rebubbling up to 5 years postop. There was significant ECL associated with rebubbling. A standardised technique reduces rebubbling and graft failure risk.