Correlation of Regional Cerebral Blood Flow Measured by Stable Xenon CT and Perfusion MRI

Abstract
The purpose of this work was to investigate the validity of perfusion MRI in comparison with stable xenon CT for evaluating regional cerebral blood flow (rCBF). The rCBF was measured by xenon CT and perfusion MRI within a 24 h interval in 10 patients (mean ± SD age 63 ± 10 years). For perfusion MRI, absolute values of rCBF were calculated based on the indicator dilution theory after injection of 0.1 mmol/kg of Gd-DTPA. Eight to 10 regions of interest (37 mm2) were located in the white and gray matter on the rCBF images for each of the 10 patients. The mean ± SD values of rCBF in gray matter were 48.5 ± 14.1 ml/100 g/min measured by xenon CT and 52.2 ± 16.4 ml/100 g/min measured by perfusion MRI. In the white matter, the rCBF was 22.6 ± 9.1 ml/100 g/min by xenon CT and 27.4 ± 6.8 ml/100 g/min by perfusion MRI. There was a good correlation of rCBF values between perfusion MRI and xenon CT (Pearson correlation coefficient 0.83; p < 0.0001). Comparable to xenon CT, perfusion MRI provides relatively high resolution, quantitative local rCBF information coupled to MR anatomy.