• Cornea

Numerous corneal graft studies have demonstrated that the Descemet’s membrane endothelial keratoplasty (DMEK) potentially delivers better patient outcomes than Descemet’s stripping endothelial keratoplasty (DSEK). Performed successfully, DMEK has been shown to deliver better and more rapid recovery of vision, although this difference has narrowed with the introduction of thinner DSEK tissue.1 2 DMEK also has lower rejection rates than DSEK.3 4

However, DMEK is considered a more challenging technique than DSEK with higher rates of early graft failure. One major randomised controlled trial (RCT) reported that surgical failures requiring retransplantation occurred in 7% of DMEK cases, compared with 0% of DSEK cases.5 Early graft failure can be caused by iatrogenic damage due to prolonged donor manipulation or upside-down orientation. Donor grafts may be difficult to unfold due to fibrin or haemorrhage sticking the DMEK scroll together and, in such cases, either the donor is reinserted after the fibrin has been removed or the donor material is lost. DMEK has also been shown to be associated with higher levels of rebubbling, usually performed if more than one third of the graft is detached.6 7 In two recent RCTs comparing EK techniques, 24% of DMEKs were rebubbled compared with only 4% of DSEK cases.5 8 A recent large cohort reported a DMEK rebubbling rate of 32%.6 Rebubbling is inconvenient for the patient and not always successful: in almost a third of rebubbled cases reported …