Prognostic factors of epiretinal membranes: A systematic review

Epiretinal membranes (ERM) have been increasingly characterized with the advent of new optical coherence tomographies (OCTs). We intended to perform a systematic review regarding prognostic factors (PF) of ERM after surgery.

Systematic review of electronic databases was performed (last date of search was 10 August 2015): Medline, Scopus, Google Scholar, clinicaltrials.gov and current controlled trials. Search queries included: "membrane", "pucker", "prognosis", "prognostic", "epiretinal", "épirétinienne". Inclusion criteria were: (1) primary purpose was to identify a PF of ERM; (2) prospective or retrospective study, case series (more than 10 patients), or clinical trials; (3) follow-up of at least 3 months; (4) complete ophthalmological evaluation in each patient with visual acuity and OCT, preoperative and≥3months after surgery; (5) vitrectomy with ERM peeling performed in each patient. Eligibility criteria verification, data extraction and evaluation of risk of bias were performed according to Cochrane's recommendations.

From 817 studies found, 21 were included (9 prospective, 12 retrospective, 0 trials). In all studies, there was significant visual acuity improvement after surgery. The majority of the studies included pars plana vitrectomy (PPV) combined with phacoemulsification.

PF for visual acuity (VA) improvement after ERM surgery included: shorter duration of symptoms before surgery, lesser central foveal thickness at baseline identified by the OCT, good integrity of the inter segment/outer segment photoreceptor junction at baseline, and thinner ganglion cell inner plexiform layer at baseline. To avoid bias, studies should analyze VA separately if phacoemulsification is also performed. The knowledge of these PF may assist in planning surgery.