Purposes: This meta-analysis aimed to compare and evaluate the morphological and functional outcomes between the inverted internal limiting membrane (ILM) flap and ILM insertion techniques in the treatment of large macular holes (MHs).
Methods: The PubMed, Embase, and Cochrane Library databases were searched for relevant studies comparing the two techniques for the treatment of large MHs. The primary outcome measures included the MH closure rate, preoperative and postoperative best-corrected visual acuity (BCVA), MH closure patterns, and external limiting membrane (ELM) and ellipsoid zone (EZ) recovery. Statistical analyses were performed using RevMan 5.3 software.
Results: Two randomized controlled trials and four retrospective studies were included in this meta-analysis. The MH closure rate did not significantly differ between the two groups (P = .93). Postoperative BCVA was not significantly different between the two groups at 3 months (P = .20) or 6 months (P = .51). ELM and EZ recovery were also similar between the two groups. However, the results for postoperative BCVA and outer retinal structure recovery tended to favor the ILM flap group based on the forest plot. There was no significant difference between the two groups for the U-shape (P = .26), V-shape (P = .65), and W-shape closure types (P = .38).
Conclusions: Our meta-analysis provides evidence that the MH closure rate and visual function outcomes are similar between the ILM flap and ILM insertion techniques in large MHs. However, based on the forest plot, postoperative BCVA and outer retinal layer reconstruction tended to favor the ILM flap technique. Further studies with larger sample sizes are required to confirm the superiority of the ILM flap to the ILM insertion technique.
Keywords: Internal limiting membrane; internal limiting membrane insertion technique; inverted internal limiting membrane flap technique; large macular hole; meta-analysis.