Repeat Keratoplasty For Failed Descemet Membrane Endothelial Keratoplasty: Potential Risk Factors

To assess the outcomes of repeat Descemet membrane endothelial keratoplasty (Re-DMEK) and determine the risk factors that cause graft failure.

Ankara Bilkent City Hospital, Cornea and External Diseases Unit

Re-DMEK was performed after primary DMEK failure in 28 (32 eyes) of 155 consecutive DMEK patients in Ankara City Hospital Ophthalmology Clinic between 2021 and 2023. Patient data, including demographic properties of patients, indications for DMEK surgery, ocular co-morbidities, preoperative visual acuity, intraocular pressure, rebubbling rates, type of tamponade used, donor age, and follow-up time, were recorded retrospectively. The data were analyzed by SPSS Statistics software (version 22.0; IBM). P≤0.05 was considered significant.

Primary DMEK indications were Fuchs endothelial dystrophy (6 eyes), pseudophakic bullous keratopathy (25 eyes), and ICE Syndrome (1 eye). Ocular co-morbidities in patients underwent Re-DMEK were;  prior vitrectomy (4 eyes), glaucoma (4 eyes) and an anterior chamber lens(1 eye) The mean preoperative best corrected visual acuity(BCVA) was 1.85 ± 0.84  logMAR. Cytomegalovirus (CMV) was detected in the anterior chamber samples of 4 patients. The mean time between the first DMEK and Re-DMEK was 12.4 ± 2.8 months. Postoperative BCVA was 0,79 ± 0.82 logMAR. A second Re-DMEK was performed on four eyes in total. Two of these patients were vitrectomized. In other patients, no graft failure was observed in their follow-up.

Comorbid glaucoma, previous vitrectomy, and the presence of CMV in anterior chamber samples are seemed to increase the risk of graft failure in patients who underwent DMEK. However second procedure may be beneficial, and repeat endothelial keratoplasty should be considered regardless.