Descemet Endothelial Thickness Comparison Trial: A Randomized Trial Comparing Ultrathin Descemet Stripping Automated Endothelial Keratoplasty with Descemet Membrane Endothelial Keratoplasty

To compare clinical outcomes of ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) in the treatment of corneal endothelial dysfunction.Patient and outcome-masked, randomized controlled clinical trial.Patients with damaged or diseased endothelium from Fuchs endothelial dystrophy or pseudophakic bullous keratopathy who were considered good candidates for DMEK or UT-DSAEK.Study eyes were randomized by the eye bank to UT-DSAEK or DMEK 1 to 2 days before surgery.The primary outcome of the trial was best spectacle-corrected visual acuity (BSCVA) at 6 months. Secondary outcomes included 3- and 12-month BSCVA; 3-, 6-, and 12-month endothelial cell counts; intraoperative and postoperative complications; and change in pachymetry.A total of 216 patients with endothelial dysfunction were screened, and 50 eyes of 38 patients were enrolled by 2 surgeons at Casey Eye Institute at Oregon HealthScience University in Portland, Oregon, and at Byers Eye Institute at Stanford University in Palo Alto, California. Overall, we found DMEK to have better visual acuity outcomes compared with UT-DSAEK after correcting for baseline visual acuity: compared with UT-DSAEK, those randomized to DMEK had 1.5 lines better BSCVA at 3 months (95% confidence interval [CI], 2.5-0.6 lines better; P = 0.002), 1.8 lines better BSCVA at 6 months (95% CI, 2.8-1.0 lines better; P0.001), and 1.4 lines better BSCVA at 12 months (95% CI, 2.2-0.7 lines better; P0.001). Average endothelial cell counts were 1963 cells/mmDescemet membrane endothelial keratoplasty had superior visual acuity results compared with UT-DSAEK at 3, 6, and 12 months in patients with isolated endothelial dysfunction with similar complication rates.