How to treat endothelial failure after PK or DMEK: is DMEK the way to go?

Abstract

Abstract Background Descemet membrane endothelial keratoplasty (DMEK) may be an elegant solution for endothelial failure after penetrating keratoplasty (PK). However, it is currently unclear whether this approach comes with any long-term drawbacks concerning chronic endothelial cell loss, rebubbling rates, graft survival and severity of immune reactions. We therefore herein compare the outcomes of DMEK to repair failed PK to the outcomes of DMEK to repair failed DMEK grafts. Methods This retrospective study included 117 patients with DMEK after keratoplasty (82 following DMEK and 35 following PK). Postoperative visual acuity, endothelial cell count, rebubbling rates, graft survival and rejection rates were recorded. Kaplan-Meier-analysis was used to assess survival rates. Results Visual acuity improved, but stayed at a lower level in PK patients. Endothelial cell loss was more severe in patients with DMEK as an initial procedure, whereas rebubbling rates, graft failure and immune reactions did not differ significantly between both groups. Ratios of graft diameters of the first and second graft did not influence survival or rejection of the graft. Conclusions Repeat DMEK is an appropriate method of treating endothelial graft failure after both DMEK and PK. The higher endothelial cell loss in the DMEK-DMEK group may be due to a different recipient endothelial reservoir and assimilate in the long term follow-up. These data may encourage treating endothelial graft failure with DMEK even in PK eyes.