Voxel-wise Parametric Mapping of Cerebrovascular Hemodynamics using 4D Flow MRI: A Scan-Rescan Reproducibility Study at 3T

Cerebrovascular dual-venc 4D flow MRI enables measurement of global and local intracranial 3D hemodynamics with full volumetric coverage of the circle of Willis. Hemodynamic analysis was completed using a semi-automated voxel-wise parametric mapping tool, enabling assessment of velocity-based parameters, including mean velocity, peak velocity, kinetic energy and time-to-peak velocity. The workflow reproducibility was evaluated with scan-rescan analysis for 10 subjects who underwent two MRI scans within 30 days. Global circle of Willis and hemispheric analysis regions showed good to excellent reproducibility for all parameters except for time-to-peak velocity. Regional analysis showed better reproducibility for parameters derived from systolic cardiac timepoints.