Comparison of retinal microvascularity in unilateral idiopathic epiretinal membrane cases with eyes without retinal pathology

Comparison of Retinal Microvascularity in Unilateral Idiopathic Epiretinal Membrane Cases with Eyes Without Retinal Pathology Purpose: The aim of this study was to analyze the effects of ERM on macular microvascular circulation in Unilateral Idiopathic Epiretinal Membrane(iERM) cases by comparing the macular microvascularity with OCT-A in the eye with ERM, the fellow eye and the age-matched control group, and to analyze whether there are changes in the vascular structure before clinical findings appear is to evaluate. Materials and Methods: Patients who applied to Karadeniz Technical University ophthalmology department between Ferbruary 2023 and May 2023 and were diagnosed with Unilateral Idıopathic Epiretinal Membrane and without any retinochoroidal disease in the fellow eye were included.Age-matched patients without retinochoroidal disease were included as control group in the study.Forty-six eyes of 23 patients with unilateral idiopathic ERM were included in the study.The right eyes of 23 patients included in the control group were selected for the study.Radial scanning macula SD-OCT and 6*6 mm OCT-Angiography images were obtained on the Solix OCT/OCT-A (Optovue Inc.Freemont ,CA,USA) device of all patients.Superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel densities in macular areas conforming to the ETDRS grid pattern, FAZ area, central foveal thickness(CFT), subfoveal choroidal thickness (SFCT) and the relationship of these parameters with visual acuity were statistically evaluaeted. Results: In the case group, both the eye with ERM and the fellow eye, foveal SCP and DCP vascular density were significantly higher than the control group (respectively; p=0,000, p=0,023, p=0,000, p=0,020). Parafovea SCP vascular density in the control group and eyes with ERM did not differ significiantly(p=0,149).In the eye group with ERM, parafovea superiorhemi SCP vascular density was found to be significiantly higher than control group(p=0,035).Parafoveal temporal SCP vascular density was found to be significiantly higher in the ERM eye and in the fellow eye compared to the control group(p=0,024, p=0,014).In parafoveal areas, DCP did not differ significiantly between the groups.The FAZ area in the eye with ERM was found to be significiantly smaller than the control group(p=0,000).CFT in the eye with ERM was significiantly higher than the control group(p=0,000).Both the ERM eye and the fellow eye had significiantly lower SFCT values compared to the control groups (p=0,009, p=0,003). Conclusion: It has been determined that the epiretinal membrane causes changes in the microvascular structure in SCP and DCP, especially in the fovea, and some of these changes also accur in the fellow eye. This indicates that there may be intrinsic pathologies in the retina before posterior vitreous detachment (PVD), which is often blamed in the etiology of ERM, occurs. The significiantly thinner subfoveal choroidal thickness in the eye with ERM and in the other healthy eye compared to the control group suggests the role of the choroid in the pathogenesis.More studies are needed to reach consistent results in this area. Key Words: Idiopathic Unilateral Epiretinal Membrane, Optical Coherence Tomography Angiography, microvascular circulation