The need of rebubbling in case of small graft detachments after Descemet Membrane Endothelial Keratoplasty (DMEK)

Purpose To investigate the need of rebubbling for small graft detachments after Descemet Membrane Endothelial Keratoplasty (DMEK). Methods In this retrospective study we evaluated 111 eyes from 111 patients that showed graft detachment after DMEK surgery and have achieved graft adherence by injection of air or 20% sulfur hexafluoride (SF6) to the anterior chamber (rebubbling group; n = 57) or by spontaneous adherence without intervention (control group; n = 54) at final examination. Subgroups in terms of the maximum height and in terms of the detachment area in relation to graft area were formed. Outcome measures were the increase in best-corrected visual acuity (BCVA) and the decrease in central corneal thickness (CCT) from the measurement before DMEK to six months after surgery and postoperative endothelial cell density. Results BCVA increased in the rebubbling group and the control group, the difference being 0.22 logMAR, p = 0.048. For eyes with a maximum height less than 500 mu m, the increase of BCVA was 0.39 +/- 0,36 logMAR in the control group and 0.62 +/- 0,53 logMAR in the rebubbling group, p = 0.045. There was no difference of statistical significance of BCVA between both groups regarding the detachment area of less than 20% in relation to graft area. The mean decrease in CCT and postoperative endothelial cell density showed no significant difference between the rebubbling group and the control group. Conclusion Compared to spontaneous graft adherence, a rebubbling shows no beneficial effect on the clinical outcome for small detached DMEK grafts. Rebubbling does not decrease postoperative endothelial cell density.