Ultrasound Vector Flow Imaging-Based Wall Shear Stress Measurement and Validation by Phase-Contrast Magnetic Resonance Imaging

Wall shear stress (WSS) is associated with arterial diseases including atherosclerosis, plaque development, and arterial stenosis, etc. Previous WSS measurements were based on magnetic resonance imaging (MRI) and computational fluid dynamics (CFD), which were time consuming with high cost. Previously, high-frame-rate vector flow imaging (HiFR-VFI) has been implemented on a clinical ultrasound scanner. Based on the HiFR-VFI, the WSS can be measured for turbulent flow in the complex shaped arteries. This paper introduced the HiFR-VFI based WSS calculation using the general equation based on vector velocities, and validated its accuracy by comparing in vivo results of 47 common carotid arteries (CCA) with the phase-contrast magnetic resonance imaging (PC-MRI) measurements. The PC-MRI based WSS was calculated using another equation based on the volume flow measurement. The WSS results from the HiFR-VFI and PC-MRI measurements were comparable, with a Pearson correlation coefficient of 0.60 and a mean absolute error of 27.6%. The clinical studies with the HiFR-VFI-based WSS and other related vascular parameters were reviewed in the end.