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Validation of VASO cerebral blood volume measurement with positron emission tomography

Cerebral blood volume (CBV) has been shown to be an important biomarker in a number of neurological disorders and in the quantitative interpretation of functional MRI. One approach to determine CBV in humans is vascular‐space‐occupancy MRI, and this technique has been applied to the studies of brain glioma, Schizophrenia, and Alzheimer's disease. However, validation of this technique with a gold standard method has not been reported. In this study, we compared vascular‐space‐occupancy MRI with a radiotracer‐based positron emission tomography technique in a group of healthy subjects. It was found that regional CBV measured with vascular‐space‐occupancy MRI was highly correlated with that of the positron emission tomography data (R = 0.79 ± 0.10, N = 8). Furthermore, absolute CBV values quantified by vascular‐space‐occupancy were also in excellent agreement with those by positron emission tomography (slope = 1.00 ± 0.15). Because of the differences in the labeling principles between the two modalities, systematic CBV differences were observed in large vessel and ventricle regions. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.