Altered Hemodynamics Associated with Pathogenesis of the Vertebral Artery Dissecting Aneurysms
Figure 1
(a) Schematic drawing of a Type I vertebral artery showed no deviation of the running. *: the configuration of the right vertebral artery was a sharp angle less than 90 defined as no deviation. Arrows show retrograde inflow into the pseudolumen from the distal entry of the dissection site. (b) Schematic drawing of a Type II vertebral artery showing mild-to-moderate deviation but not over the midline. **: the configuration of the vertebral artery was an obtuse angle defined as mild-to-moderate deviation. The midline was defined as the line from the septum pellucidum to the anterior median fissure as assessed by basiparallel anatomic scanning (BPAS)—MR imaging. Arrows show retrograde inflow into the pseudolumen. from the distal entry of the dissection. (c): schematic drawing of a Type III vertebral artery deviating remarkably to the contralateral side over the midline. Arrows show retrograde inflow into the pseudolumen. from the distal entry of the dissection.
