Functional and Anatomical Micro-Structural Recovery of Idiopathic Macular Holes Following the Inverted Internal Limiting Membrane Flap Technique: A Long-Term Study

<b>Background</b>: Idiopathic macular holes (MHs) are typically treated with pars plana vitrectomy and internal limiting membrane (ILM) peeling. The inverted ILM flap (ILMF) technique has emerged for MHs, but long-term outcome data remain inadequately established. This study evaluates the long-term functional and anatomical outcomes of the ILMF in idiopathic MHs. <b>Methods</b>: We evaluated 71 consecutive eyes of patients with idiopathic MHs who underwent vitrectomy with the inverted ILMF. Follow-up duration was more than 12 months. Visual acuity was measured, and macular anatomy was monitored with optic coherence tomography (OCT). Long-term visual and anatomical outcomes were defined a priori and analyzed accordingly. <b>Results</b>: Final vision values showed significant improvement compared to preoperative ones, from 1.02 [Snellen Equivalent (SE), 19/200] ± 0.40 logarithm of the minimum angle of resolution (logMAR) to 0.47 (SE, 68/200) ± 0.39 logMAR (<i>p</i> < 0.001). The primary MH closure rates were 94.37% (67/71), while the secondary closure rate reached 97.18% (69/71). Factors associated with better final vision included smaller hole size, favorable hole stage, better preoperative vision, intact postoperative foveal microstructure and contour. The recovery of the external limiting membrane (ELM), inner and outer segment junction (IS/OS), and good foveal contour had improved to 73.4%, 40.3%, and 49.3% at one year and 80%, 71.4%, and 53.3% at three years postoperatively, respectively. <b>Conclusions</b>: In idiopathic MHs, the ILMF approach provides meaningful, long-term visual and microstructural recovery, especially with a favorable functional outcome and intact postoperative microstructure sustaining up to three years.