Spotlight on the Internal Limiting Membrane Technique for Macular Holes: Current Perspectives

Pars plana vitrectomy has become the standard procedure for primary macular holes (MHs) repair, including the removal of the posterior cortical vitreous, the stripping of eventual epiretinal membranes, and finally an intraocular gas tamponade. During this procedure, peeling the internal limiting membrane (ILM) has been proven to increase closure rates and avoid postoperative reopening in several researches. In fact, even in large MHs more than 400 µm, the advantage of peeling off the ILM was highlighted by better anatomical closure rates. Nevertheless, some authors suggested that ILM peeling is not always essential, because it generates various side effects in retinal structure and function. Furthermore, the ideal amount of ILM peeling and the most effective strategies for removing the ILM are still subject of research. Different surgical modifications have been reported as alternatives to traditional peeling in certain clinical settings, including ILM flaps, ILM scraping, and foveal sparing ILM peeling. As regards large MHs, the introduction of ILM inverted flap appeared as a game changer, offering a significantly higher >90% closure rate when compared to traditional ILM peeling. Modifications to inverted ILM flap procedures have been claimed in recent years, in order to define the best area and direction of ILM peeling and its correlation with functional outcomes. Moreover, several innovations saw the light in the setting of recurrenMHs, such as ILM free flap transposition, inverted ILM flap combined autologous blood clot technique, neurosensory retinal flap, and human amniotic membrane (HAM) plug, claiming higher anatomical success rate also in those complex settings. In conclusion, the aim of this review is to report how the success rate of contemporary macular surgery has grown since the turn of the century, especially for big and chronic MHs, analyzing in which way ILM management became a crucial point of this kind of surgery.