Perifoveal Microvascular Changes Following Internal Limiting Membrane Peeling Surgery for Epiretinal Membrane and Macular Hole

Introduction: To evaluate perifoveal microvasculature changes following pars plana vitrectomy with internal limiting membrane (ILM) peeling for epiretinal membrane (ERM) and macular hole (MH).Methods: This retrospective study included 59 eyes from 59 patients. Subjects were divided into two groups: a ERM group (n = 43) and a MH group (n = 16) based on the initial diagnosis. Swept-source optical coherence tomography angiography (SS-OCTA) was performed in the macular area, pre- and postoperatively. Perifoveal microvascular changes were calculated using MATLAB from the 6 x 6 mm SS-OCTA images, excluding the foveal avascular zone. Pre- and postoperative perifoveal vessel density (pfVD) was separately analyzed in six sectors (superior, superiotemporal, inferiotemporal, inferior, inferionasal and superionasal) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). The baseline characteristics and other clinical factors were compared between the ERM and MH groups.Results: The postoperative best corrected visual acuity significantly improved in both groups (p < 0.05). One year after surgery, the pfVD in the SCP of ERM group significantly decreased in the inferotemporal sector (p = 0.049). The postoperative pfVD in the DCP of the MH group significantly decreased in temporal sectors (p < 0.05, respectively). The postoperative mean pfVD in the SCP in the MH group was significantly lower than that in the ERM group (p = 0.003). The presence of a dissociated optic nerve fiber layer (DONFL) was 75% in the MH group and 22% in the ERM group (p = 0.018). The correlation between the pfVD and DONFL was not statistically significant.Conclusion: Postoperative pfVD reduction in the temporal sector, a corresponding area in which DONFL is present after MH surgery, was significantly observed. After vitreoretinal surgery in MH patients, OCTA may serve as a useful tool for monitoring perifoveal microvascular changes, especially in temporal sectors.

Automated summary

This study aimed to evaluate the perifoveal microvascular changes following pars plana vitrectomy with internal limiting membrane (ILM) peeling for epiretinal membrane (ERM) and macular hole (MH) patients. The results showed that there was a significant reduction in perifoveal vessel density (pfVD) in specific sectors after surgery, especially in patients with macular hole.