The effect of inner limiting membrane peeling on visual fields: Unravelling a source of bias in glaucoma management

Pars plana vitrectomy (PPV) with inner limiting membrane (ILM) peeling aims to improve visual function. Previous studies have focused on visual acuity, often neglecting visual field (VF) changes. This systematic review examines VF changes after PPV with ILM peeling in patients with epiretinal membrane (ERM) or macular hole (MH), including those with glaucoma, who have preexisting VF damage, to identify potential biases in glaucoma management. The inclusion criteria were as follows: (A) Patients undergoing ILM peeling for ERM or MH and (B) VF outcomes assessed through standard automated perimetry (SAP) or Goldmann kinetic perimetry. Exclusions were non-English studies and those with fewer than 30 subjects. Data included retinal disease, demographics, VF outcomes (mean deviation [MD], pattern standard deviation, and central VF sensitivity [CVFS]), study design, and use of stains. Out of 612 studies, 23 met our criteria. Of these, four included glaucoma patients and seven involved concomitant phacoemulsification. In glaucoma patients, two studies showed MD improvement in the central 24°, while one showed deterioration in the central 10°, linked to worse preoperative MD and older age. Among studies without glaucoma patients, three of eight using SAP reported increased VF defects (VFDs); two showed lower outer nasal CVFS postoperatively. Indocyanine green staining was linked to higher VFD incidence while triamcinolone acetonide or tryptane blue staining led to no significant VFDs. The nasal half of the central VF was more affected, possibly due to retinal ganglion cell distribution. Further prospective studies, including randomized controlled trials, are needed to better understand ILM-peeling effects.