Outcomes of Descemet Membrane Endothelial Keratoplasty in Eyes With a Previous Descemet Stripping Automated Endothelial Keratoplasty Graft

Purpose: To analyze the outcomes of Descemet membrane endothelial keratoplasty (DMEK) in eyes with previous Descemet stripping automated endothelial keratoplasty (DSAEK). Methods: This retrospective interventional case series included 26 eyes (26 patients) that underwent DMEK to replace a previous DSAEK graft with at least 6 months of follow-up. The outcome measures were indications for surgery, best spectacle-corrected visual acuity (BSCVA), endothelial cell density, rebubbling rate, rejection, and failure. Results: Patient age was 71.9 +/- 12.6 years. The average follow-up time after DMEK was 15.1 +/- 10.6 months. Indications for DMEK were DSAEK graft failure (69%) and a DSAEK suboptimal visual outcome (31%). BSCVA of the entire cohort (n = 26) improved from 1.33 +/- 0.78 logMAR preoperatively to 1.04 +/- 0.78 and 1.06 +/- 0.89 logMAR at 6 months postoperatively and at the last follow-up, respectively (P = 0.019 and P = 0.033). BSCVA among eyes without visual comorbidities (n = 13) improved from 0.84 +/- 0.50 logMAR preoperatively to 0.55 +/- 0.47 and 0.51 +/- 0.49 logMAR at 6 months postoperatively and at final follow-up, respectively (P = 0.023 for both). Of these eyes, 84.6% had improvement in BSCVA at 6 months postoperatively and at last follow-up. In the subgroup of 8 eyes with DMEK for suboptimal visual outcomes after DSAEK, BSCVA improved from 0.81 +/- 0.44 to 0.52 +/- 0.35 logMAR at final follow-up (P = 0.024). When excluding eyes with visual comorbidities, BSCVA of this subgroup (n = 5) improved from 0.54 +/- 0.32 to 0.36 +/- 0.25 logMAR at final follow-up (P = 0.038). BSCVA of this subgroup at 6 months postoperatively was not significantly different from preoperative BSCVA, when including visual comorbidities (n = 8, 0.75 +/- 0.60 logMAR, P = 0.79) and when excluding visual comorbidities (n = 5, 0.40 +/- 0.28 logMAR, P = 0.621). Endothelial cell density decreased from 2753 +/- 307 cells/mm(2) to 1659 +/- 655 cells/mm(2) 6 months after surgery (39.7% loss, P = 0.005). Three eyes (11.5%) required rebubbling, and 5 eyes (19.2%) had secondary graft failure at 2 to 20 months. Conclusions: DMEK is effective for replacing previous DSAEK not only for graft failure but also for suboptimal visual outcomes.