AIM: To study the effect of vitrectomy combined with macular epiretinal membrane peeling on visual acuity, central macular thickness(CMT)and metamorphopsia degree in patients with idiopathic macular epiretinal membrane(IMEM).

METHODS: Totally 31 cases(31 eyes)of patients with IMEM were treated with vitrectomy combined with macular epiretinal membrane peeling, and the best corrected visual acuity(BCVA), CMT, ellipsoid zone(IS/OS)connectivity and macular morphology were examined before and after operation. The treatment effect was assessed, and the relationship between BCVA, macular structure and morphology before and after operation was studied. All the factors that might affect the surgical outcomes were analyzed.

RESULTS: The mean BCVA and CMT were 0.59±0.14 and 429.35±86.17μm respectively before operation, and were decreased to 0.38±0.09 and 304.87±62.54μm at 6mo after operation(P<0.05). The metamorphopsia degree after operation was gradually decreased, and the metamorphopsia degree at 1, 3 and 6mo after operation was lower than before operation(P<0.008). At 1mo after operation, the IS/OS connectivity ratios were 65%, and there was no significant difference compared with that before operation with 52%(P>0.008). The ratio of IS/OS connectivity was 81% and 90% at 3mo and 6mo after operation, and the difference was statistically significant compared with that before operation(P<0.008). There was significant difference in the macular morphology at different time after operation(P<0.008). The proportions of patients with normal macular morphology at 1, 3 and 6mo after operation were 26%, 52% and 77% respectively, and the differences were statistically significant compared with before operation(P<0.008). Pearson or Spearman correlation analysis showed postoperative BCVA in IMEM patients was positively correlated with preoperative BCVA and postoperative CMT(P<0.05), but that was negatively correlated with preoperative macular morphology, preoperative and postoperative IS/OS connectivity and postoperative macular morphology(P<0.05).

CONCLUSION: Vitrectomy combined with macular epiretinal membrane peeling can significantly reduce the CMT of patients with IMEM, and improve the IS/OS connectivity and macular morphology, so as to improve the visual acuity and reduce the metamorphopsia degree.