[DMEK for endothelial decompensation after penetrating keratoplasty]

In recent years, the Descemet membrane endothelial keratoplasty (DMEK) has become the standard transplantation procedure for endothelial corneal diseases due to faster visual recovery and lower graft rejection rates compared to penetrating keratoplasty (pKPL). Endothelial corneal decompensation after pKPL is also a possible indication for DMEK. The question is which intraoperative and postoperative aspects need to be considered.

We retrospectively reviewed the DMEK surgeries performed in our clinic in 2020 and 2021 after pKPL (n = 10) regarding intraoperative and postoperative characteristics as well as functional and morphological results.

Of the 10 eyes analyzed a repeat pKPL could be avoided by DMEK in 7 cases. The initial situation of the eyes was very different with respect to corneal decompensation, the primary indications for pKPL and number of previous pKPLs. The rate of postoperative gas re-injections (re-bubblings) was 80%, in some cases requiring multiple gas injections. A 20% sulphur hexafluoride (SF6) gas-air mixture was used for gas endotamponade. The improvement in visual acuity was highly variable. Overall, visual acuity in the treated eyes increased by 5.1 ± 1.4 lines after DMEK in the pKPL eyes (p < 0.001, minimum 3 lines, maximum 7 lines; logMAR preoperative 1.48 ± 0.36 to logMAR postoperative 0.57 ± 0.28).

The use of DMEK for endothelial graft failure after pKPL is a possible minimally invasive procedure to avoid repeat pKPL. The postoperative follow-up requires significantly more re-bubblings due to the altered anatomical situation and geometry of the posterior corneal surface after pKPL and the resulting poorer adhesion of Descemet's lamella.