Abstract:Abstract Objective: To investigate the differences in morphological structure and retinal blood perfusion between the affected eye and the contralateral healthy eye in patients with idiopathic macular epiretinal membrane (IMEM) before and after surgery, and to evaluate the association of these parameters with functional and anatomical outcomes to inform prognostic assessment. Methods: A prospective, observational cohort study was conducted at Zhejiang Provincial People’s Hospital between January 2023 and December 2024. Thirty consecutive patients diagnosed with unilateral IMEM were enrolled; the fellow eye served as an internal control. All participants underwent standardized ophthalmic evaluations, including best-corrected visual acuity (BCVA), optical coherence tomography (OCT), optical coherence tomography angiography (OCTA), and color fundus photography. Key quantitative parameters assessed included central macular thickness (CMT), foveal avascular zone (FAZ) area, vessel density in the inner capillary plexus (ICP), superficial capillary plexus (SCP), deep capillary plexus (DCP), and choroidal capillary perfusion area (CCPA). Measurements were obtained preoperatively and at 1 and 3 months postoperatively. Correlation analyses were performed between baseline and longitudinal imaging/functional metrics and postoperative BCVA and CMT. Results: At baseline, IMEM-affected eyes demonstrated significantly reduced BCVA, DCP density, and FAZ area, alongside significantly increased CMT and CCPA (P< 0.05), compared with contralateral controls. Following vitrectomy with membrane peeling, CMT decreased significantly at both 1 and 3 months (P < 0.05) postoperatively; BCVA improved significantly by 3 months, and DCP density showed partial but statistically significant recovery at 3 months (P < 0.05). No significant change in FAZ area was observed postoperatively (P > 0.05). Correlation analyses revealed that 3-month BCVA was negatively associated with 3-month CMT. Preoperative DCP density and FAZ area were negatively correlated with 1-month CMT, whereas preoperative CMT and 1-month ICP/SCP densities were positively correlated with 1-month CMT. Furthermore, 3-month CMT was negatively associated with preoperative DCP and positively associated with preoperative CMT. Conclusion:In patients with IMEM, the affected eyes exhibit significantly reduced DCP density and FAZ area, alongside increased CMT and CCPA. Following vitrectomy with membrane peeling, foveal thickness decreased progressively, DCP density demonstrated partial restoration, and BCVA improved gradually. Preoperatively, smaller CMT and larger DCP and FAZ were associated with more favorable surgical outcomes; postoperatively, smaller ICP/SCP densities—combined with a larger FAZ—also correlated with better functional recovery.
