Quantitative Evaluation of Mean Transit Times Obtained with Dynamic Susceptibility Contrast-Enhanced MR Imaging and with 133Xe SPECT in Occlusive Cerebrovascular Disease

OBJECTIVE. We report on quantitative mean transit time images obtained using dynamic susceptibility contrast-enhanced MR imaging after an IV bolus injection of a contrast agent. Our study compared cerebral hemodynamics measured using dynamic susceptibility contrast-enhanced MR imaging with the cerebral perfusion reserve obtained using dynamic 133Xe single-photon emission computed tomography (SPECT).SUBJECTS AND METHODS. Seventeen patients with chronic cerebral artery occlusion or stenosis diagnosed by digital subtraction angiography were examined. Dynamic susceptibility contrast-enhanced MR imaging data were acquired using a multishot echoplanar sequence. Our procedure for quantification of mean transit time was based on the indicator dilution theory and deconvolution analysis.RESULTS. The increased mean transit time values obtained with dynamic susceptibility contrast-enhanced MR imaging correlated well (r=-0.789, p < 0.0001) with decreased cerebral perfusion reserve determined by performing dynamic 133X...