Assessment of Regional Cerebral Blood Volume in Acute Human Stroke by Use of Single-Slice Dynamic Susceptibility Contrast-Enhanced Magnetic Resonance Imaging

Abstract

Background and Purpose The purpose of this study was to evaluate the clinical usefulness of dynamic susceptibility contrast-enhanced MRI (DSC-MRI) in acute cerebral ischemia. Methods During bolus injection of gadolinium-diethylenetriamine pentaacetic acid, a series of rapid T 2 *-weighted images was recorded from one slice. Concentration-time curves and images of regional cerebral blood volume (rCBV) were calculated from this data set. DSC-MRI, MR angiography, conventional spin-echo MRI (SE-MRI), and CT were performed in 11 patients within 6 hours after stroke onset and before thrombolytic or anticoagulant treatment was begun. A follow-up MRI examination was performed 24 to 48 hours after stroke onset. Results In 7 of 11 patients (group 1) with territorial infarcts of the middle (n=6) or posterior cerebral artery (n=1), DSC-MRI showed reduced rCBV in the affected territory before conventional SE-MRI displayed ischemic lesions. DSC-MRI was helpful to differentiate severely ischemic tissue from peri-infarct parenchyma. Partial reperfusion (n=3), unchanged reduction of rCBV (n=2), and progressive reduction of rCBV (n=2) were observed in the follow-up study. Normal DSC-MRI findings were present in 4 of 11 patients (group 2) with lacunar infarcts. Conclusions DSC-MRI accomplished the detection of the ischemic territory in the very early stage (<6 hours) before SE-MRI delivered unequivocal results. DSC-MRI might be helpful to discriminate completely ischemic tissue from potentially salvageable ischemic parenchyma at risk and may play an important role in stroke therapy and evaluation.