Long-term Clinical Outcomes of Macular Hole Surgery Using Internal Limiting Membrane Flap or Insertion

Purpose: To evaluate the long-term outcomes of inverted internal limiting membrane (ILM) flap and ILM insertion in idiopathic macular hole (MH) and to compare the outcomes between the two techniques. Methods: We retrospectively reviewed the medical records of 17 eyes that underwent an inverted ILM flap procedure (flap group, n = 9) or ILM insertion procedure (insertion group, n = 8) for idiopathic MH. Within each group, best-corrected visual acuity (BCVA) before surgery was compared with that at the final follow-up. The BCVA at the final follow-up was compared between the two groups. In addition, the incidence of restoration of the external limiting membrane (ELM) and ellipsoid zone was evaluated. Results: The mean follow-up period was 25.1 ± 13.7 months after surgery. All MHs were closed after the surgery. In all 17 eyes, the logarithm of minimal angle of resolution BCVA had improved significantly from a mean value of 0.88 ± 0.23 before surgery to 0.42 ± 0.23 at the final follow-up (p < 0.001). The BCVA was significantly improved in both the flap group (from 0.92 ± 0.25 to 0.37 ± 0.29, p = 0.007) and the insertion group (from 0.83 ± 0.19 to 0.48 ± 0.15, p = 0.018). There was no significant difference in BCVA at the final follow-up between the two groups (p = 0.075). The incidence of restoration of the ELM and ellipsoid zone was significantly higher in the flap group (seven eyes, 77.8%) than in the insertion group (one eye, 12.5%). Conclusions: Both inverted ILM flap and ILM insertion are effective in MH treatment. The restoration of retinal outer layers was better in the flap group. Further studies with a larger study population are needed to evaluate the long-term visual outcomes of the two methods. J Korean Ophthalmol Soc 2021;62(3):329-336