PURPOSE: To determine whether nonsupine positioning (NSP) is noninferior to face-down positioning (FDP) in full-thickness macular hole (FTMH) surgery.

METHODS: This is a single-center, open-label, randomized controlled trial. Between October 2013 and October 2014, pseudophakic participants underwent pars plana vitrectomy, internal limiting membrane peeling, and perfluoropropane gas tamponade and were randomly allocated to either FDP or NSP. The primary (noninferior) outcome was FTMH closure. The sample size was based on an estimated 95% closure rate and a -15% noninferiority margin for the NSP group. The secondary outcome was Early Treatment Diabetic Retinopathy Study visual acuity at 3 months. Additionally, intraocular gas fill on postoperative Day 4 was measured.

RESULTS: Eighty-one participants were enrolled. Final analysis of 68 participants demonstrated equal closure rates in both positioning groups: 33/34 (97.1%; 95% confidence interval: 84.7-99.9). Closure rates in the ≥400-μm FTMH subgroup were similar, 93.8% and 100.0% in the FDP and NSP groups, respectively (P = 0.43). Final visual acuity did not differ significantly between the groups (P = 0.60). Median gas fill was 78% (range: 57-86) in the FDP group and 76% (range: 56-85) in the NSP group (P = 0.51). Gas fill in closed FTMHs was significantly higher than in unclosed FTMHs (P = 0.02).

CONCLUSION: Nonsupine positioning is noninferior to FDP in FTMH surgery. Furthermore, results suggest that the degree of gas fill affects FTMH closure.