Usefulness of Susceptibility-Weighted Imaging (SWI) for Patients with Acute Ischemic Stroke

We analyzed brain perfusion status using the new non-enhanced MR sequence, SWI MR venography, in patients with acute ischemic stroke. Twenty-one patients who had acute cortical infarction within 24 hours after symptom onset were enrolled. Seventeen of these patients showed spontaneous blood oxygen level-dependent (BOLD) signaling by SWI, which indicated abnormal venous flow. In this group, increased BOLD signals disappeared before the phase of vasogenic edema, therefore increased BOLD signals may be related to "misery perfusion" on perfusion imaging in acute stroke. Evidence of embolous signals was seen with SWI in 13 patients, compared with 7 patients by T2* sequence. The SWI technique is a proven noninvasive and powerful MR sequence for evaluating brain perfusion abnormality and embolic signals after acute stroke.