Inverted internal limiting membrane flap technique for large macular holes: a systematic review and single-arm meta-analysis

The aim of this systematic review was to determine the anatomical outcome—macular hole (MH) closure rate—and functional outcome—visual acuity (VA) improvement rate—of the inverted internal limiting membrane (ILM) flap technique for large MH. We searched for articles on large MH (> 400 μm) treated with inverted ILM flap technique in databases as of December 1, 2017. And single-arm meta-analysis was performed for the primary outcome of MH closure rate and the secondary outcome of VA improvement rate. In addition, we searched and pooled studies treating large MH with indocyanine green (ICG)-assisted ILM peeling as the reference. R software (version 2.15.2) was used for analysis. This review includes eight studies that used inverted ILM flap technique to treat large MH (> 400 μm). Based on the single-arm meta-analysis performed in R 2.15.2, the pooled MH closure rate and VA improvement rate following inverted ILM flap technique were 95% (95% CI, 88 to 98%) and 75% (95% CI, 62 to 85%), respectively, in fixed-effect models. There was no substantial methodological heterogeneity. In addition, we selected four studies on large MH treated with ICG-assisted ILM peeling as the reference. The fixed-model pooled MH closure rate and VA improvement rate were 87% (95% CI, 79 to 92%) and 57% (95% CI, 46 to 68%), respectively. Inverted ILM flap technique should be an effective and safe method for treating large MH, with high closure rates and good VA improvement. However, further studies in large randomized controlled trials on minimizing surgical complications and understanding the mechanism of this technique are necessary.