Histopathologic Features of Descemet Membrane Endothelial Keratoplasty Graft Remnants, Folds, and Detachments

Purpose: To describe the histologic features of postmortem eyes after Descemet membrane endothelial keratoplasty (DMEK) and their potential clinical implications. Design: Histopathologic study. Participants: Eleven postmortem DMEK corneas of 8 patients who underwent surgery for Fuchs endothelial dystrophy, with an average postoperative time of 4 +/- 1.9 years (range, 7 monthse-6.5 years). Methods: Eleven corneas transplanted with a DMEK graft were procured after death and processed for light microscopy evaluation. Main Outcome Measures: Histologic findings at the donorehost interface and at the host edge. Results: Of the 11 corneas available for analysis, 9 showed normal anatomic features in the corneal center; that is, the donor-host interface resembled that of a virgin eye. One eye also had an anatomically normal periphery, but the remaining 10 eyes showed specific abnormalities in the periphery. Nine demonstrated overlapping of the DMEK graft onto the host edge of the descemetorhexis (and in 6 of these, the overlapping tissue showed a contracted inward fold at its peripheral edge with scar tissue); 1 eye showed a dense, acellular scar overlying a portion of the DMEK graft that clinically had shown a detachment followed by spontaneous adherence; 3 eyes showed subtle graft folds with scar tissue anteriorly; in 2 eyes (of the same patient), the anterior banded layer of the host Descemet membrane (DM) was still in situ across the cornea (both of these eyes had required rebubbling); and 2 eyes showed host DM remnants within the corneolimbal tunnel incision that may have interfered with incisional wound healing. Conclusion: Incomplete host DM removal may relate to postoperative DMEK graft detachment and wound instability. Graft detachments may reattach with interface scarring. Rebubbling procedures may be performed within 4 to 6 weeks, before portions of the detached graft scar. Subtle DMEK graft folds may explain subjective reports of monocular diplopia. (C) 2016 by the American Academy of Ophthalmology