Three-dimensional phase contrast velocity mapping acquisition improves wall shear stress estimation in vivo

Noninvasive determination of spatial distribution and temporal gradient of wall shear stress at common carotid artery

“…It is partially because there is no widely accepted method for WSS measurement in vivo, and only several subjects were included in previous studies. Mean WSS values in CCAs reported in these studies were about 0.74-1.02 N/m 2 (Hoeks et al, 1995;Oyre et al, 1998a, b;Wu et al, 2004). The results obtained in the present study were within this range.…”

Flow–area relationship in internal carotid and vertebral arteries

“…Flow waveforms have been characterized in common carotid arteries from DUS measurements (Holdsworth et al, 1999) and in internal carotid arteries and vertebral arteries from PC-MR measurements (Ford et al, 2005). Others have calculated WSS from measurements of flow and area in common carotid arteries (Wu et al, 2004;Oshinski et al, 2006), brachial arteries (Dammers et al, 2003) and internal carotid arteries (Box et al, 2007).…”

A Reconstruction Method for Gappy and Noisy Arterial Flow Data

“…Most of these measurements have been restricted to the axial velocity component in a single plane or even in a single location. In [35], WSS derived from the 3-D MR PC velocity mapping measurements did not differ from the 2-D velocity measurements both in vivo or in vitro. Accurate estimation of WSS vectors requires accurate measurement of the near-wall velocity vector field and accurate identification of the vessel wall location.…”

“…8(a) illustrates the number of the (computational) grid lines that have been skipped upon interpolating the true (CFD) field. A typical in-plane spatial resolution for both MRI and CDUS is about 500 m [23] but in-plane resolutions of have recently become available [35]. Mesh 1 is equally-spaced in each direction with resolution m, m, which is somewhat beyond the limit of currently used CDUS devices.…”

“…The computed WSS had errors up to 40%, however, a simple smoothing of the image boundary data reduced the errors to less than 16%. Time-resolved direct measurements of WSS remains a great challenge despite isolated successes using MRI or Doppler US methods (see [18], [25], [26], [31], [32], [35] and [2], [6], [14], respectively). Most of these measurements have been restricted to the axial velocity component in a single plane or even in a single location.…”