In previous studies testing the efficacy of the TOS special tests, Doppler ultrasonography was shown to visualize vascular abnormalities and confirmed the diagnosis in patients with at least five positive provocative (special) tests. (Gillard, Perez-Cousin, Hachulla, Remy et al 2001). Our research team would like to confirm this previous finding and further expand on this topic by examining for the changes in blood flow with Doppler ultrasonography during the performance of these special tests.