In patients with MS undergoing pelvic venography as part of a CCSVI evaluation, there was a 17% incidence of May-Thurner syndrome. Historically, there is a reported incidence of MTS in 6.3–24% of an asymptomatic population [1, 2]. This data therefore suggests that MS patients do not have an increased incidence of MTS. Given these findings, and the fluoroscopic exposure time and contrast dose required to evaluate the pelvic vasculature for MTS as part of a CCSVI venogram, we do not support the routine performance of pelvic venography during these procedures, unless the patient has a history of DVT or leg swelling. http://www.jvir.org/article/S1051-0443%2811%2900039-X/fulltext