Descemet Membrane Endothelial Keratoplasty for Graft Failure After Descemet Stripping Endothelial Keratoplasty: Clinical Results and Histopathologic Findings.

IMPORTANCE: The management of graft failure is increasingly relevant with the spread and growing acceptance of endothelial keratoplasty.

OBJECTIVES: To investigate the functional and anatomical results of secondary Descemet membrane endothelial keratoplasty (DMEK) for graft failure after Descemet stripping endothelial keratoplasty (DSEK) and to histologically analyze the stroma-to-stroma interface with respect to clinical implications.

DESIGN, SETTING, AND PARTICIPANTS: In a single-surgeon prospective comparative case series at the Department of Ophthalmology, Charité-University Medicine Berlin, Berlin, Germany, 8 eyes (3.8%) of 210 consecutively performed DMEK procedures underwent a secondary DMEK for graft failure after DSEK from March 1, 2012, through February 28, 2013. Those cases were compared with the eyes of a reference collective (n = 30) and matched-pairs group (n = 8) after primary DMEK for Fuchs endothelial dystrophy.

INTERVENTION: Descemet membrane endothelial keratoplasty.

MAIN OUTCOMES AND MEASURES: Postoperative best-corrected visual acuity (BCVA) and central corneal thickness at 1, 3, 6, and 12 months. Intraoperatively obtained DSEK graft lenticels were investigated immunohistochemically.

RESULTS: Patients with graft failure after DSEK had a mean (SD) age of 79.4 (7.2) years (range, 70-90 years). Preoperatively, the mean (SD) BCVA was 1.13 (0.50) logMAR (20/250 Snellen equivalents), and the mean (SD) central corneal thickness measured 704 (161) µm. Twelve months postoperatively, the mean (SD) corneal thickness decreased to 524 (27) µm after secondary and 516 (27) µm after primary DMEK (P = .57). A mean (SD) BCVA of 0.38 (0.36) logMAR (20/50 Snellen equivalents) was achieved after secondary DMEK compared with 0.15 (0.15) logMAR (20/28 Snellen equivalents) after primary DMEK. Histologically, failed DSEK graft lenticels presented condensations of collagen layers. Fibronectin and cytokeratin were accumulated along the stroma-to-stroma interface; vimentin was found in loosened graft stroma.

CONCLUSIONS AND RELEVANCE: These data suggest that DMEK might be considered a feasible choice in patients with graft failure after DSEK. However, the visual restitution might be impeded because of preceded depositions of matrix proteins within the corneal stroma and the stroma-to-stroma interface, which are associated with corneal fibrosis. Thereby, fibrotic processes might be avoided by performing a secondary DMEK in an early phase of graft failure.