Relationship between Macular Microvasculature and Visual Function in Idiopathic Macular Epiretinal Membrane by Using OCT Angiography and Multifocal Electroretinogram

Purpose: To investigate the relationship between microvasculature and visual function in idiopathic epiretinal membrane (iERM).

Methods: This retrospective study included 30 iERM eyes. Macular microvasculature was evaluated by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). Visual function was evaluated by best corrected visual acuity (BCVA) and multifocal electroretinogram (mfERG). All parameters were measured in the iERM patients at baseline, 1 month, and 3 months postoperatively. Associations between macular microvasculature and visual function were evaluated.

Results: BCVA, central retinal thickness (CRT) and parafoveal vessel density (PFVD) of the deep capillary plexus (DCP) changed significantly 3 months after surgery. P1 amp density and amplitude of ring 1 decreased significantly 3 months postoperatively. P1 implicit time of ring 1 was shortened after surgery. Baseline PFVD of DCP was negatively correlated with the postoperative BCVA, and baseline BCVA was positively correlated with the postoperative BCVA. Baseline foveal avascular zone (FAZ) and P1 amplitude of ring 1 were positively correlated with the postoperative P1 amplitude of ring 1 (p < 0.05). Multiple linear regression analysis revealed that baseline PFVD of DCP was a predictor of the postoperative BCVA, and baseline FAZ was a predictor of the postoperative P1 amplitude of ring 1 (p < 0.05).

Conclusion: Although visual acuity and CRT improved after iERM surgery, visual function estimated by mfERG had a limited recovery 3 months postoperatively. Baseline PFVD of the DCP and FAZ were predictors of visual function after the iERM surgery.