Flow-induced disturbances In balanced steady-state free precession images: Means to reduce or exploit them

Abstract

In this work computer simulations and phantom measurements are presented that show the effect of flow on in-plane balanced steady-state free precession images. The images were studied for various flow velocities, excitation regions, relaxation times, RF-pulse angles, and off-resonance frequencies. The work shows that flow-induced disturbances are present in the images, but can be reduced by the application of inhomogeneous excitation regions. Also, a velocity quantification method that utilizes the disturbances was developed and proved to quantify flow velocities accurately. The work concluded that the flowinduced disturbances can be reduced to improve image quality, but can also be exploited to quantify the flow velocity. Magn Reson Med 61:893-898, 2009. © 2009 Wiley-Liss, Inc.