Evidence regarding the effect of a face-down posture (FDP) for large idiopathic macular hole (IMH) is inconsistent. We conducted a systematic review and meta-analysis to determine whether a postoperative FDP is required for the treatment of large IMH. Eligible randomized controlled trials published before September 2021 were retrieved from the Medline, Embase, and Cochrane Library databases. The efficacy outcome was the IMH closure rate and the visual acuity improvement rate. A meta-analysis was performed using a random effects model. The "Grading of Recommendations Assessment, Development, and Evaluation" approach was implemented, and the numbers needed-to-treat (NNTs) were calculated. Seven studies comprising 640 patients were included. We performed a predefined subgroup analysis of IMH size using a cut-off point of 400 µm. Compared with non-FDP, a significant effect of FDP was found in the IMH > 400 µm group (OR = 3.34; 95% CI = 1.57-7.14; trial sequential analysis-adjusted CI = 1.20-11.58; NNTs = 7.9). After stratifying by the posturing periods, the beneficial effect of FDP lasting at least five days, but not three days was observed for large IMH. Maintaining a FDP for at least five days postoperatively is an effective strategy (certainty of evidence: "moderate") for treating large IMH.
Keywords: face-down posture; idiopathic macular holes; systemic review.