Visual acuity changes after epiretinal membrane peeling

Abstract

Purpose: To review functional and anatomical outcomes after idiopathic epiretinal membrane (ERM) peeling focusing on the visual gain between 1 month and 3 months postoperatively and to compare visual recovery depending on lens status and ERM peeling combined or not with cataract surgery. The secondary outcome was to review the rate and causes of visual loss after ERM peeling.

Methods: A retrospective analysis was performed on 160 eyes from 160 consecutive patients who had undergone vitrectomy and ERM peeling in 2012. Cases were classified into 3 groups, according to the lens status: pseudophakic patients, phakic patients who underwent ERM peeling alone and phakic patients who underwent ERM peeling combined with phacoemulsification and intraocular lens implantation. Best-corrected visual acuity (BCVA) and central macular thickness as measured on optical coherence tomography were reviewed at baseline, 1 month and 3 months after surgery. In case of VA decline, OCT and all information in chart were also reviewed to identify the cause.

Results: Mean BCVA improved significantly in all groups at 1 month (p < 0,0001) and 3 months (p < 0,0001) after surgery. The visual gain at 1 month and 3 months post-operatively was significantly higher in the combined surgery group compared to ERM peeling alone, in phakic and pseudophakic eyes (p = 0.02). BCVA did not significantly improved between 1 month and 3 months postoperatively (p = 0,1863). In phakic eyes, a slight decrease of mean BCVA was even found between months 1 and 3. Fourteen eyes (8.75%) had a visual loss 3 months after surgery compared to preoperative BCVA. The main cause was Irvine Gass syndrome, diagnosed in 4 of these patients (2.5%): 2 were phakic, 1 pseudophakic and 1 underwent combined surgery.

Conclusions: In modern ERM surgery, improvement in BCVA occurs mainly during the first month after surgery. The visual gain was significantly higher in the combined surgery group due to the benefit of cataract removal. Visual gain increased very little between month 1 and 3 and even decreased slightly in phakic patients, suggesting a mild effect of post-vitrectomy cataract.

Keywords: 762 vitreoretinal surgery • 585 macula/fovea • 754 visual acuity