Figure 1c. Images in a patient with acute right-sided hemiparesis. (a) Transverse echo-planar T2*-weighted MR image (0.8/29) shows the susceptibility sign (arrow), which indicates arterial occlusion within left MCA. Diameter of the affected vessel is larger than that of contralateral unaffected MCA. (b) Individual section of MR angiography (30/5.4) selected from the entire three-dimensional data set at the corresponding anatomic level shows absence of flow signal within left MCA. (c) Transverse maximum intensity projection displays acute proximal MCA occlusion (arrow).