Using fourier velocity encoded MRI data to guide CFD simulations

Fourier velocity encoding (FVE) is a promising magnetic resonance imaging (MRI) method for assessment of cardiovascular blood flow. FVE provides considerably higher signal-to-noise ratio than phase contrast (PC) imaging, is robust to partial-volume effects and can be acquired rapidly using spiral readouts. On the other hand, FVE data do not directly provide a velocity map. These maps are useful for calculating the actual blood flow through a vessel, or for guiding computational fluid dynamics simulations (CFD). In this paper, FVE data were simulated from PC velocity maps from a pulsatile carotid flow phantom; velocity maps were then reconstructed from these FVE data, and used to guide CFD simulations. FVE-guided CFD velocity fields were qualitatively and quantitatively compared with the PC-measured velocity field, with the pure CFD solution, and with PC-guided CFD. The results show that FVE-guided CFD achieves better agreement with the PC-measured velocity field than pure CFD. Compared with PC-guided CFD, FVE provides considerably better results than PC with similar scan time, and equivalent results when compared with PC with 9 times longer scan time.