Evaluation of inner segment/outer segment junctions in different types of epiretinal membranes

ABSTRACT Purpose: This study was conducted to evaluate the relationships of inner/outer segment (IS/OS) junction disruption, macular thickness, and epiretinal membrane (ERM) grade with best-corrected visual acuity (BCVA), as well as the relationship between IS/OS junction disruption and ERM grade. Methods: Fifty-four eyes of 54 patients with different grades of ERM were retrospectively reviewed. Patients were classified into three groups by ERM grade according to retinal striae and vessel distortion: grade/group 1, visible membranes without retinal striae or vessel distortion; grade/group 2, mild to moderate macular striae or vessel straightening; and grade/group 3, moderate to severe striae and vascular straightening. Correlations of BCVA with age, central retinal thickness, ERM grade, and IS/OS disruption as well as of IS/OS disruption, central macular thickness, and BCVA with ERM grade were evaluated. Results: Twenty-nine (53.7%) eyes exhibited IS/OS junction disruption. Groups 1 and 2 differed significantly with respect to BCVA (p=0.038), but groups 2 and 3 did not (p=0.070). Central macular thickness was significantly greater in group 2 than in group 1 (p=0.031) and in group 3 than in group 2 (p=0.033). Groups 1 and 2 differed significantly in terms of IS/OS disruption (p=0.000), but groups 2 and 3 did not (p=0.310). Conclusions: The IS/OS junction appears to be disrupted during the early stages of ERM. Grade 3 ERM is associated with a significantly higher incidence of IS/OS disruption.

摘要 目的：本研究旨在评估视网膜内外节（inner/outer segment, IS/OS）连接中断、黄斑厚度及视网膜前膜（epiretinal membrane, ERM）分级与最佳矫正视力（best-corrected visual acuity, BCVA）的相关性，同时探讨IS/OS连接中断与ERM分级之间的关联。方法：回顾性分析54例不同ERM分级患者的54只患眼。根据视网膜条纹及血管扭曲程度，将患者按ERM分级分为3组：1级/组：可见膜样结构，无视网膜条纹或血管扭曲；2级/组：轻至中度黄斑条纹或血管拉直；3级/组：中至重度条纹及血管拉直。评估BCVA与年龄、视网膜中央厚度、ERM分级、IS/OS中断的相关性，以及IS/OS中断、黄斑中央厚度、BCVA与ERM分级的相关性。结果：53.7%（29只）患眼存在IS/OS连接中断。1组与2组的BCVA差异具有统计学意义（p=0.038），但2组与3组差异无统计学意义（p=0.070）。2组的黄斑中央厚度显著高于1组（p=0.031），3组黄斑中央厚度亦显著高于2组（p=0.033）。1组与2组的IS/OS中断情况差异具有统计学意义（p=0.000），但2组与3组差异无统计学意义（p=0.310）。结论：ERM早期阶段即可出现IS/OS连接中断。3级ERM患者的IS/OS中断发生率显著升高。