Abstract:AIM: To investigate the differences in morphological structure and retinal blood perfusion between the affected eye and the contralateral healthy eye using optical coherence tomography angiography(OCTA)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 study was conducted at Zhejiang Provincial People's Hospital between January 2023 and December 2024. Consecutive patients diagnosed with unilateral IMEM were enrolled; the fellow eye served as an internal control. All participants underwent standardized ophthalmic evaluations, including optical coherence tomography(OCT), OCTA, and color fundus photography. Key quantitative parameters assessed included best-corrected visual acuity(BCVA), 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 mo postoperatively. Correlation analyses were performed between the above parameters and postoperative BCVA and CMT.
RESULTS: This study enrolled 30 patients(60 eyes)diagnosed with IMEM, comprising 14 males and 16 females, with a mean age of 65.4±10.8 y.At baseline, IMEM-affected eyes demonstrated significantly reduced BCVA, DCP density, and FAZ area, alongside significantly increased CMT and CCPA, compared with contralateral controls. Following vitrectomy with membrane peeling, CMT decreased significantly at both 1 and 3 mo(both P<0.05)postoperatively; DCP density and BCVA showed significant improvement(both P<0.05). No significant change in FAZ area was observed postoperatively(P>0.05). At 3 mo postoperatively, BCVA of the affected eye was negatively correlated with CMT(r=-0.549, P=0.022). At 1 mo postoperatively, CMT was negatively correlated with preoperative DCP and FAZ, positively correlated with preoperative CMT, and positively correlated with ICP and SCP at 1 mo postoperatively, and negatively correlated with FAZ at 1 mo postoperatively(all P<0.05). Furthermore, CMT at 3 mo postoperatively was negatively correlated with preoperative DCP(r=-0.498,P=0.042).
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, CMT decreased progressively, DCP density demonstrated partial restoration, and vision improved gradually. Preoperatively, smaller CMT larger DCP, and FAZ were associated with more favorable surgical outcomes; postoperatively, smaller ICP and SCP densities—combined with a larger FAZ—also correlated with better functional recovery.
