In vivo wall shear stress measurements using phase-contrast MRI

Abstract

There is growing evidence to suggest that endothelial biology and atherosclerosis depend on arterial wall shear stress (WSS). We review the existing literature on in vivo measurements of WSS in healthy individuals using phase-contrast MRI, which is a promising, noninvasive technique for determinating various blood flow characteristics. WSS data exist for the following arteries: carotid, brachial, aorta and femoral. Measured values indicate that WSS is site specific, a finding which opposes the notion that physiological WSS values are maintained at a constant magnitude in all parts of the arterial system. Among the WSS values obtained at the same site by different investigators there is qualitative agreement; however, differences exist in absolute values mainly due to the dependence on the method used to obtain WSS values from velocity data.

Keywords::

• atherosclerosis
• blood flow
• in vivo measurement
• phase-contrast MRI
• wall shear stress

Acknowledgments

This work has been supported by grants from the S. Niarchos Foundation and the D. Contominas Foundation.

Financial disclosure

The authors are members of the Ultimate IVUS project. This work was supported in part by NSF Grant IIS-0431144, UH Texas Learning and Computation Center, and a NSF Graduate Research Fellowship. The patent on vasa vasorum imaging belongs to Boston Scientific. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the NSF.