Comparison Between Total CBF Values Measured by ASL and Phase Contrast Over Increased Range of CBF Values

Noam Alperin¹, Murat Bagci, Sang H. Lee, Lara Eftimov², Birgit Ertl-Wagner²

ASL utilizes the water in arterial blood as endogenous contrast agent to assess cerebral blood perfusion and therefore is becoming more commonly used. A perfusion image is generated by subtracting a tagged image from a control image, where the tagged image is acquired following the labeling of the blood upstream. The time delay between the labeling and the image acquisition is the transient time. The choice of this delay can affect the derived CBF values. This project aims to compare between measurements of total CBF obtained with ASL and phase contrast MRI. The comparison was done over a wide range of CBF values by manipulating the subjects end tidal pCO2 level. Results from this comparison suggest that the PC based tCBF values could be used for calibrations of relative ASL derived CBF values.