Quantification of Wall Shear Stress in Large Blood Vessels Using Lagrangian Interpolation Functions with Cine Phase-Contrast Magnetic Resonance Imaging

Purpose The purpose of the present article was to determine the changes in luminal vessel area, blood flow, and wall shear stress in both the inflow artery and the venous stenosis of arteriovenous polytetrafluoroethylene (PTFE) grafts. Methods and materials Polytetrafluoroethylene grafts were placed from the carotid artery to the ipsilateral jugular vein in 8 castrated juvenile male pigs. Contrast-enhanced magnetic resonance angiography (MRA) with cine phase-contrast magnetic resonance imaging (MRI) was performed 2 weeks after graft placement. Results The mean wall shear stress at the venous stenosis was 4 times higher than the control vein, while the inflow artery was only 2-fold higher. By day 14, venous stenosis had formed, which was characterized by narrowed area and elevated blood flow. Conclusion By day 14, there is venous stenosis formation in porcine arteriovenous PTFE grafts with increased shear stress with decreased area when compared to control vein.

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Measurement of Absolute Epicardial Coronary Artery Flow and Flow Reserve With Breath-Hold Cine Phase-Contrast Magnetic Resonance Imaging

Circulation ◽

10.1161/01.cir.91.10.2627 ◽

1995 ◽

Vol 91 (10) ◽

pp. 2627-2634 ◽

Cited By ~ 64

Author(s):

Geoffrey D. Clarke ◽

Robin Eckels ◽

Curtis Chaney ◽

Dorothy Smith ◽

Jason Dittrich ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Coronary Artery ◽

Magnetic Resonance ◽

Phase Contrast ◽

Breath Hold ◽

Resonance Imaging ◽

Flow Reserve ◽

Contrast Magnetic Resonance ◽

Artery Flow ◽

Cine Phase Contrast

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In Vivo Tracking of the Human Patella Using Cine Phase Contrast Magnetic Resonance Imaging

Journal of Biomechanical Engineering ◽

10.1115/1.2800868 ◽

1999 ◽

Vol 121 (6) ◽

pp. 650-656 ◽

Cited By ~ 86

Author(s):

F. T. Sheehan ◽

F. E. Zajac ◽

J. E. Drace

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Knee Joint ◽

Phase Contrast ◽

Three Dimensional ◽

Resonance Imaging ◽

Contrast Magnetic Resonance ◽

Knee Joint Kinematics ◽

Cine Phase Contrast

Improper patellar tracking is often considered to be the cause of patellar-femoral pain. Unfortunately, our knowledge of patellar-femoral-tibial (knee) joint kinematics is severely limited due to a lack of three-dimensional, noninvasive, in vivo measurement techniques. This study presents the first large-scale, dynamic, three-dimensional, noninvasive, in vivo study of nonimpaired knee joint kinematics during volitional leg extensions. Cine-phase contrast magnetic resonance imaging was used to measure the velocity profiles of the patella, femur, and tibia in 18 unimpaired knees during leg extensions, resisted by a 34 N weight. Bone displacements were calculated through integration and then converted into three-dimensional orientation angles. We found that the patella displaced laterally, superiorly, and anteriorly as the knee extended. Further, patellar flexion lagged knee flexion, patellar tilt was variable, and patellar rotation was fairly constant throughout extension.

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