Quantification of complex flow using MR phase imaging—A study of parameters influencing the phase/velocity relation

doi:10.1016/0730-725X(92)90368-A

Magnetic Resonance Imaging

Volume 10, Issue 1, 1992, Pages 13-23

https://doi.org/10.1016/0730-725X(92)90368-A Get rights and content

Abstract

In this study, we describe how motion-induced phase angle is affected by different flow models and imaging parameters when using the MR flow phase mapping technique. In a phantom with straight as well as constricted tubes, simulating healthy and stenotic vessels, nonpulsatile flow in the velocity range 0–1 m/sec was maintained. The phase/velocity relation was studied for various degrees of complex flow caused by the constriction, and regions with a breakdown in linearity were determined. Further studies in these regions were made regarding the influence of pulse sequence parameters on the phase/velocity relation. The results showed that in poststenotic areas characterized by so-called separated flow, the phase/velocity relation became nonlinear due to dephasing effects. In regions with fully developed turbulent flow in straight tubes, however, no breakdown in linearity was observed. Parameters seen to have a substantial influence on the phase/velocity relation were first- and second-order velocity encoding and voxel size. Finally, a pilot in vivo demonstration of complex flow was done using a sequence designed to be robust with respect to linearity of the phase/velocity relation. The results indicate that the MR phase mapping technique can be used to measure flow quantitatively in regions with complex flow. This opens possibilities for future clinical use of the technique in the study of areas of complex flow such as valvular heart disease.

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^☆: This study was supported by grants from the Danish Heart Foundation, The Danish and Swedish Medical Research Councils, and the Swedish Society of Medicine.

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Original contributionQuantification of complex flow using MR phase imaging—A study of parameters influencing the phase/velocity relation☆

Abstract

Magn. Reson. Imaging

Magn. Reson. Imaging

Am. Heart J.

Magn. Reson. Imaging

NMR diffusion and flow measurements and an introduction to spin phase graphing

J. Phys. E.: Sci. Instrum.

Blood flow effects in magnetic resonance imaging

AJR

MR angiography with gradient motion refocusing

J. Comput. Assist. Tomogr.

Three-dimensional phase contrast angiography

Magn. Reson. Med.

Blood flow imaging by cine magnetic resonance

J. Comput. Assist. Tomogr.

Visualization of moving fluid. Quantitative analysis of blood flow velocity using MR imaging

Radiology

Human abdominal aorta: Comparative measurements of blood flow with MR imaging and multigated Doppler US

Radiology

MR angiography and dynamic flow evaluation of the portal venous system

AJR

Static zones in the internal carotid artery: Correlation with boundary layer separation and stasis in model flows

Br. J. Radiol.

A model for acute haemodynamic studies in the ascending aorta of the pig

Cardiovasc. Res.

Blood flow imaging with MR: Spin-phase phenomenon

Radiology

Original contribution
Quantification of complex flow using MR phase imaging—A study of parameters influencing the phase/velocity relation☆