Flow-Weighted IVASO-DS for Absolute Arterial CBV Quantification

Kathrin Lorenz¹, Toralf Mildner¹, Andre Pampel¹, Harald E. Mller¹

Inflow vascular-space-occupancy with dynamic subtraction (iVASO-DS) is a non-invasive MRI method for absolute arterial cerebral blood volume (aCBV) quantification. In the present study, mild flow-weighting (FW) gradients were added to the imaging readout. Experiments without FW gradients show a significant drop of the measured aCBV from more than 3% at TI=839ms to about 1.5% at TI=1143ms in regions which are dominated by signals from larger-scale arteries. This drop is explained by non-inverted blood reducing the iVASO-DS contrast at longer TI. It is shown that experiments with FW gradients effectively remove this source of error yielding aCBV values of about 1%.