Dynamic Contrast-Enhanced T2*-Weighted Imaging in Acute Cerebral Infarction: Usefulness in Assessment of Cerebral Hemodynamics

ABSTRACT

PURPOSE: To evaluate the usefulness of dynamic contrast-enhanced T2*-weighted MR imaging for assessing cerebral hemodynamics in acute cerebral infarction. MATERIALS AND METHODS: We performed dynamic T2*-weighted imaging(TR/TE/flip angle 40/26/10 degrees, 64 x 128 matrix, 5 sec scan time) in conjunction with conventional T1- andT2-weighted imaging and MR angiography in 20 patients with acute cerebral infarction. The regions of ischemia seenon T2-weighted image(high signal intensity), MR angiogram(vascular stenosis or occlusion) and dynamic contrast-enhanced T2*-weighted image(perfusion defect) were topographically compared with each other. Relative cerebral blood volumes(rCBVs) of the ischemic regions and of contralateral normal regions were calculated fromsignal intensity data measured on dynamic contrast-enhanced T2*-weighted images, and were compared. RESULTS: Regions of ischemia were topographically well correlated on T2-weighted image, MR angiogram and dynamic contrast-enhanced T2*-weighted image in all but two patients, of whom one had recanalization of the occluded artery and the other had a small infarction. rCBVs were asymmetrically reduced in the ischemic regions in all butone patient who had recanalization of the occluded artery. CONCLUSION: Dynamic contrast-enhanced T2*-weighted imaging is a useful method in the qualitative and quantitative assessment of cerebral hemodynamics in acutecerebral infarction. The use of this imaging technique along with conventional MR imaging and MR angiography provides better hemodynamic information in acute cerebral infarction.