A Case of Self-Detachment of a Stage 3 Idiopathic Epiretinal Membrane Due to Posterior Vitreous Detachment

We report our findings in a case in which the retinal traction caused by an epiretinal membrane (ERM) was relieved by a spontaneous posterior vitreous detachment (PVD). A 53-year-old woman complained of visual disturbances in both eyes. Her decimal best-corrected visual acuity (BCVA) was 1.2 (about 20/16 in Snellen units) in both eyes with no abnormalities in the anterior chamber, lens, or vitreous. Ophthalmoscopy and optical coherence tomography revealed a Stage 3 ERM in the right eye with a foveal macular thickness (FMT) of 408 μm and an intact posterior hyaloid membrane. The M-chart score was 0° in both the horizontal and vertical directions. She was followed with observation only. Eight months later, the patient returned with a complaint of floaters in the right eye. Her decimal BCVA remained at 1.2 in both eyes with no retinal tears, retinal detachment, or vitreous hemorrhage. However, a PVD was detected with a detachment of the ERM into the vitreous cavity. The FMT had decreased to 389 μm, and the macular traction appeared to be relieved. The detachment of the ERM reduced the retinal traction, and the BCVA was maintained during the 27-month follow-up period. This case shows the long-term stability without decreasing BCVA or recurrence of an ERM. We suggest that the detachment of the ERM was due to the development of a PVD which then led to the release of retinal traction. We recommend that surgery not be performed in cases of idiopathic ERM without a PVD and with good visual acuity and no metamorphopsia. Instead, these cases should be carefully monitored for visual symptoms and a worsening of the traction on the retina.