Cystoid macular edema after epiretinal membrane surgery: Incidence, risk factors and evolution with treatments

Abstract

Purpose To report the incidence, the risk factors and the evolution after treatment of cystoid macular edema (CME) complicating epiretinal membrane (ERM) surgery. Methods This study included 647 consecutive patients with ERM operated by 23‐gauge parsplana vitrectomy between January 2011 and July 2013. Combined phacoemulsification of the lens was performed in 71% of cases. Patients were considered as having a CME if they presented augmentation of central macular thickness with presence of cysts on OCT scans in the first year after surgery. Patients with history of retinal detachment, vein occlusion, uveitis, diabetic macular edema or neovascular AMD were excluded. Results The incidence of CME was 2.6% (16/605) occurring within an average time of 129 ± 101 days. Predictive factors were the presence of preoperative CME on OCT scans (p=0.04) and preoperative prostaglandin use (p=0.02). Combined phacoemulsification was not identified as a risk factor. Treatment consisted in topical applications of non‐steroidal anti‐inflammatory drugs (NSAIDs) associated with dexamethasone and/or acetazolamide for a mean duration of 4 months. Intravitreal or subconjonctival corticoids injections were performed in 6 patients. A two‐line or more improvement in visual acuity was achieved respectively in 6 of 14 (43%) and 4 of 6 patients (67%). A dissipation of cysts on OCT scans was observed respectively in 4 of 14 (29%) and in 5 of 6 patients (83%). Conclusion The incidence of CME after ERM surgery was 2.6%. Preoperative prostaglandin use and preoperative CME were associated with an increased risk of postoperative CME. Treatment with NSAIDs was effective in about one third of patients, corticoids injections in 5 of 6 patients.