Macular diseases: epiretinal membrane.

Epiretinal membrane (ERM) is a relatively common macular disease, which forms along the surface of the internal limiting membrane of the retina. Currently, microincision vitrectomy surgery (MIVS) has been confirmed as a minimally invasive and very safe modality of treatment that is useful for improving vision. However, some cases have shown poor visual recovery even after complete removal of the ERM. Since the introduction of spectral domain optical coherence tomography (SD-OCT) was demonstrated to be useful for the noninvasive diagnosis and monitoring of macular diseases, the appearance of the photoreceptor layer on SD-OCT images has been found to be an important prognostic factor for visual recovery and postoperative best-corrected visual acuity after MIVS. Although deciding when to perform a vitrectomy can be difficult, it might be better to schedule vitrectomy surgery while the photoreceptor inner segment/outer segment (IS/OS) junction remains intact. If the preoperative IS/OS junction has already been disrupted, the surgery should be scheduled as early as possible to avoid further disturbances of visual improvement.