LAUSR

PURPOSE The Eye Drops for Early Morning-Associated Swelling (EDEMAS) trial assessed the efficacy of hyperosmolar eye drops on corneal edema resolution. DESIGN Double-blind randomized-controlled trial of hyperosmolar eye drops vs. placebo. PARTICIPANTS Participants with Fuchs' dystrophy scheduled for Descemet membrane endothelial keratoplasty. METHODS One eye was randomized to hyperosmolar eye drops (treatment); the fellow eye was randomized to artificial tears (placebo). After baseline exam in the afternoon, corneas were examined using Scheimpflug tomography after eye opening in the morning. Participants received eye drops twice. Imaging was repeated every 30 minutes up to four hours. MAIN OUTCOME MEASURES Decrease in central corneal thickness one hour after eye opening (primary endpoint); corneal thickness, subjective visual function, glare, visual acuity, and adverse events (secondary endpoints). RESULTS 68 participants received the allocated intervention (59 eyes treatment, 55 eyes placebo). All eyes had stromal edema; none had epithelial edema. Corneal thickness was 626 μm in the treatment arm and 622 μm in the placebo arm after eye opening, indicating an early-morning edema compared to baseline of +21 μm and +24 μm, respectively. Decrease in corneal thickness after one hour was -10.5 μm in the treatment arm (95% CI, -12.8 to -8.2) and -11.2 μm (95% CI, -13.6 to -8.9) in the placebo arm (between-arm difference, 0.7 μm, 95% CI, -2.0 to 3.5; p = 0.59), indicating no clinically relevant effect of hyperosmolar eye drops on early-morning corneal edema. Results were not compatible with a relevant treatment effect on corneal thickness, visual acuity, and glare over the entire course of the study. Increase in subjective visual function was less rapid in the treatment arm than in the placebo arm. Adverse events, most commonly burning after eye drop application, were more common with treatment (30 eyes) than placebo (1 eye; risk difference, 49 percentage points; 95% CI, 36 to 62). CONCLUSIONS In this double-blind randomized-controlled trial, resolution of early-morning stromal edema was not accelerated by hyperosmolar eye drops, which frequently caused adverse events. These results are not compatible with a clinically relevant effect of hyperosmolar eye drops and do not support their routine use.