Fig. 3
From: Neurovascular 4DFlow MRI (Phase Contrast MRA): emerging clinical applications
Source magnitude and phase slice taken from a 4D flow acquisition with velocity encoding as in Fig. 2. The subtraction of these phases results in images which are proportional to velocity. Post-processing tools generate a 4D velocity field which allows the extraction of features of the flow field such as wall shear stress, and flow rates, relative pressures and also enables visualization of complex velocity patterns
