Pars plana vitrectomy with internal limiting membrane flap versus pars plana vitrectomy with conventional internal limiting membrane peeling for large macular hole

BACKGROUND: Macular hole (MH) is a full-thickness defect in the central portion of the retina that causes loss of central vision. According to the usual definition, a large MH has a diameter greater than 400 µm at the narrowest point. For closure of MH, there is evidence that pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling achieves better anatomical outcomes than standard PPV. PPV with ILM peeling is currently the standard of care for MH management; however, the failure rate of this technique is higher for large MHs than for smaller MHs. Some studies have shown that the inverted ILM flap technique is superior to conventional ILM peeling for the management of large MHs. OBJECTIVES: To evaluate the clinical effectiveness and safety of pars plana vitrectomy with the inverted internal limiting membrane flap technique versus pars plana vitrectomy with conventional internal limiting membrane peeling for treating large macular holes, including idiopathic, traumatic, and myopic macular holes. SEARCH METHODS: The Cochrane Eyes and Vision Information Specialist searched CENTRAL, MEDLINE, Embase, two other databases, and two trials registries on 12 December 2022. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that evaluated PPV with ILM peeling versus PPV with inverted ILM flap for treatment of large MHs (with a basal diameter greater than 400 µm at the narrowest point measured by optical coherence tomography) of any type (idiopathic, traumatic, or myopic). DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane and assessed the certainty of the body of evidence using GRADE. MAIN RESULTS: = 0%; 4 studies, 276 eyes; moderate-certainty evidence) and type 1 MH closure (RR 1.31, 95% CI 1.03 to 1.66; P = 0.03, I² = 69%; 4 studies, 276 eyes; moderate-certainty evidence). One study reported that none of the 38 participants experienced postoperative retinal detachment. AUTHORS' CONCLUSIONS: We found low-certainty evidence from four small RCTs that PPV with the inverted ILM flap technique is superior to PPV with ILM peeling with respect to BCVA gains at three or more months after surgery. We also found moderate-certainty evidence that the inverted ILM flap technique achieves more overall and type 1 MH closures. There is a need for high-quality multicenter RCTs to ascertain whether the inverted ILM flap technique is superior to ILM peeling with regard to anatomical and functional outcomes. Investigators should use the standard logMAR charts when measuring BCVA to facilitate comparison across trials.