Biomarkers in the pathogenesis of epiretinal membrane and myopic traction maculopathy: Effects of internal limiting membrane incompliance and posterior staphyloma

Background: This study compared the structural and vascular intraretinal changes between epiretinal membrane and myopic traction maculopathy eyes. Methods: An observational retrospective study of treatment-naïve epiretinal membrane and myopic traction maculopathy eyes was conducted to identify biomarkers of a 3 × 3 mm macular region centered on the fovea, using optical coherence tomography angiography. Results: The myopic traction maculopathy and epiretinal membrane groups comprised 27 and 32 eyes, respectively. In the myopic traction maculopathy group, the spherical equivalent was more myopic and the axial length was longer than in the epiretinal membrane group. Myopic traction maculopathy eyes had larger outer and smaller inner retinal volumes, larger area and perimeter of foveal avascular zones, greater circularity of foveal avascular zones, and smaller foveal vessel density in the superficial layer than epiretinal membrane eyes. Internal limiting membrane incompliance and staphyloma were significantly more in the myopic traction maculopathy group than in the epiretinal membrane group. Conclusions: The intraretinal changes in myopic traction maculopathy eyes compared with epiretinal membrane eyes showed larger avascular zones, which may have been caused by tangential internal limiting membrane incompliance. Anteroposterior traction forces from staphyloma in myopic traction maculopathy eyes may lead to larger outer retinal volumes. In epiretinal membrane eyes, traction forces confined to the superficial retina caused large inner retinal volumes and foveal acircularity.