PURPOSE. To present the vitreoretinal interface in diabetic macular edema (DME) associated with both epiretinal membrane (ERM) and incomplete posterior vitreous detachment (PVD), as detected by spectral-domain optical coherence tomography (SD-OCT). METHODS. In a retrospective study, findings were analyzed in one eye in consecutive patients. Excluded were eyes that had undergone vitreoretinal intervention or that had complete PVD or complete vitreous attachment. RESULTS. Of 44 eyes with DME and ERM, incomplete PVD was apparent in 23 (52.2%) eyes. A hyperreflective unified ERM/posterior vitreous cortex (PViC) membrane, or EVi membrane, was apparent in various sizes in 20 (87.0%) of the 23 eyes. This unified membrane (n = 20) was associated with vitreopapillary adherence in 19 (82.6%) of 23 eyes. Two major OCT presentations (n = 23) were encountered: incomplete vitreopapillary detachment (n = 11; 25% of 44), with attachment to the macular ERM, and posterior vitreous detachment from the macula, associated with vitreopapillary adhesion (n = 10; 22.7%), in four different manifestations. In the remaining two eyes, there was no association between the ERM and the PViC. CONCLUSIONS. In eyes with DME, ERM, and incomplete PVD, the posterior cortical vitreous and ERM appeared as one united EVi membrane in various lengths in most eyes, typically associated with vitreopapillary adhesion. These findings may have clinical importance in the context of epimacular membrane characteristics and its removal in DME. (Invest Ophthalmol Vis Sci. 2011; 52: 6414-6420) DOI: 10.1167/iovs.10-6781