Association of Microvasculature Changes with Visual Outcomes in Idiopathic Epiretinal Membrane Surgery: A Clinical Trial

<b>Purpose:</b> The purpose of this paper is to evaluate macular microvascular changes and their correlation with visual outcomes after idiopathic epiretinal membrane (iERM) surgery. <b>Methods:</b> Forty-seven eyes operated for iERM were included in this retrospective case series. The foveal avascular zone (FAZ) area, and the vessel density (VD) in the superficial and the deep capillary plexus (SCP and DCP) were evaluated using optical coherence tomography angiography (OCTA). The association between the OCTA parameters and best-corrected visual acuity (BCVA) was examined preoperatively and postoperatively. Regression analyses were conducted to determine the potential predictive factors for visual recovery. <b>Results:</b> At baseline, the FAZ area in iERM eyes was significantly smaller than that in the control eyes (<i>p</i> < 0.001). iERM eyes also had a lower macular VD in both the SCP and the DCP (<i>p</i> < 0.001). Preoperative BCVA was negatively correlated with the FAZ area (r = -0.499, <i>p</i> < 0.001) and macular VD in the DCP (r = -0.422, <i>p</i> = 0.003). A negative correlation was also found between postoperative BCVA and macular VD in both the SCP (r = -0.394, <i>p</i> = 0.006) and the DCP (r = -0.569, <i>p</i> < 0.001). In the bivariate analyses, age, preoperative BCVA, iERM stage, and baseline macular VD in the SCP were significantly associated with BCVA at 6 months post-surgery. Multivariate regression analysis revealed that the preoperative BCVA was the only predictor of visual outcomes in iERM eyes (<i>p</i> < 0.001). <b>Conclusions:</b> Idiopathic epiretinal membrane (iERM) causes microvascular changes, including foveal avascular zone (FAZ) contraction and decreased macular vessel density (VD) in both the superficial capillary plexus (SCP) and the deep capillary plexus (DCP). These changes were significantly correlated with pre- and/or postoperative best-corrected visual acuity (BCVA). However, none of these alterations appeared to have prognostic value for visual outcomes in patients with iERM.