Study On The Structural Changes Of Macular Area Before And After Vitrectomy For Idiopathic Epiretinal Membrane

Objective:To delve into the structural changes of macular area in IMEM patients who accept vitrectomy together with ILM removal and its relevance to visual prognosis.Methods:The clinical data of 30 patients with IMEM who received vitrectomy combined with ILM peeling in the ophthalmology department of Shengjing Hospital affiliated to China Medical University were collected from January 1,2019 to January 1,2021.Best corrected visual acuity,Central foveal thickness,Central macular volume,and macular Ganglion cell-inner plexiform layer thickness of each region were measured several times including 1 week before surgery,1 month after surgery,and 3 months after surgery.Statistical methods such as repeated measures and two-sample t test are applied to analyze the corresponding data.Results:The mean LogMAR BCVA were 0.66±0.21,0.56±0.23 and 0.47±0.22 respectively within 1 week before surgery,1 month after surgery,and 3 months after surgery.The LogMAR BCVA significantly improved 3 months after surgery compared with that data 1 week before surgery(P<0.05).The data of CFT measured at each time point,1 week before surgery and 1 month,3 months after surgery,were 521.06±94.08μm,426.28±57.21 μm and 354.41±59.74μm respectively.At 1 month and 3 months after surgery,CFT dwindled obviously compared with that data before surgery(P<0.05).CV was 15.32±2.41 mm3,12.5±2.09 mm3 and 9.75±2.02 mm3,respectively,within 1 week before,1 month after and 3 months after surgery.A dramatic decline in CV was found in perioperative period(P<0.05).Three months after the operation,the shrinkage of mean mGCIPL thickness and the minimum mGCIPL thickness manifested statistical significance(P<0.05).The thickness of mGCIPL in each part was reduced.The decrease of the inferotemporal mGCIPL thickness was statistically significant(P<0.05).Revealed by correlation analysis,neither CFT nor CV showed significant relationship to LogMAR BCVA.The greater the mean mGCIPL thickness(r=-0.377,P=0.0488)and the lower temporal mGCIPL thickness(r=-0.572,P=0.0003)at 3 months postoperatively could significantly relate to better prognostic visual acuity.The mean thickness of mGCIPL at 1 month postoperatively was of predictive value for the decimal BCVA≥0.4(AUC=0.8326,P=0.0021)and ≥0.2(AUC=0.7896,P=0.0074)at 3 months postoperatively.Conclusions:Vitrectomy combined with ILM peeling was effective in improving postoperative visual acuity and restoring the anatomical structure of macular area.The lower postoperative mGCIPL thickness relate to worse postoperative visual acuity.The mean mGCIPL thickness at 1 month after surgery has predictive value for BCVA at 3 months after surgery.