Preoperative Posterior Stromal Ripples as Predictive Biomarkers of Visual Recovery After DMEK

Purpose: To investigate the role of preoperative posterior stromal ripples (pre-PSR) on visual acuity recovery after Descemet membrane endothelial keratoplasty (DMEK). Methods: This is a comparative case series retrospectively analyzing patients who underwent DMEK. Electronic records and imaging of DMEK patients were reviewed. The last preoperative and first postoperative available anterior segment optical coherence tomography scans for each eye were analyzed for the presence of pre-PSR. The difference in longitudinal trends of visual acuity recovery after DMEK was assessed in eyes with and without pre-PSR. The frequency of rebubbling and measures of proportional relative risk of rebubbling were analyzed according to the presence of preoperative and postoperative PSR. Results: A total of 66 patients (71 eyes) were included. Pre-PSR were associated with lower preoperative visual acuity [0.6 (0.5) vs. 0.9 (0.6) LogMAR, P = 0.02] and higher central corneal thickness [613 (73.8) vs. 715.7 (129.6) micron, P < 0.001]. Eyes with pre-PSR had a slower visual recovery up to 3.5 months after surgery compared to eyes without pre-PSR and achieved lower final visual acuity [0.1 (0.2) vs. 0.3 (0.3) LogMAR, P = 0.02]. Cox proportional hazard ratios showed that postoperative PSR were associated with a greater risk of rebubbling [hazard ratio (95% CI), 7.1 (1.3, 39.5), P = 0.02] while pre-PSR were not. Conclusions: The presence of pre-PSR is associated with slower visual recovery and lower final visual acuity after DMEK while postoperative PSR confer a higher risk of rebubbling. PSR represent a valuable prognostic biomarker both before and after DMEK.