[A new technique to facilitate donor preparation for DMEK surgery]

Descemet membrane endothelial keratoplasty (DMEK) is becoming more and more the method of choice to treat corneal endothelial diseases in specialized centers. The reasons that prevent this technique from becoming widespread are the delicate donor tissue preparation. By inverting the curvature of the cornea from convex to concave after mounting onto an artificial anterior chamber, we developed a combined manual delamination and hydrodissection technique, which allows a rapid and endothelium-preserving method of separating donor Descemet membranes from the underlying stroma.

Experiments were perfomed with 60 donor corneas that were not suitable for transplantation. Donor age ranged between 42 and 94 years. Two experimental groups were formed: 1 inverse manual delamination (n = 16) and 2 combined manual delamination and hydrodissection (n = 44). All experiments were undertaken by an experienced surgeon who was, however, not experienced with these techniques. We examined the frequency of Descemet membrane rupture as well as the amount of induced endothelial damage (trypan blue staining with quantitative image analysis).

Significant lesions of Descemet's membrane that would have led to a loss of the graft occurred in 25% of the manual delamination cases and in 4.5% using the combined technique. Endothelial damage induced by both techniques was low (6 and 5.2%, respectively).

For DMEK donor preparation, a combination of manual delamination and hydrodissection was shown to be a safe and endothelium-protective technique to separate Descemet membranes from the underlying stroma. A very rapid learning curve for the combination technique is of specific additional interest for beginners in DMEK surgery.