Peak velocity determination using fast Fourier velocity encoding with minimal spatial encoding.

Daniela Galea; M Louis Lauzon; Maria Drangova

doi:10.1118/1.1494829

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PubMed · 12201419

Peak velocity determination using fast Fourier velocity encoding with minimal spatial encoding.

Daniela Galea·M Louis Lauzon·Maria Drangova

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Abstract

For quantitative peak velocity determination, a technique was developed that uses Fourier velocity encoding (FVE) for the fast acquisition of images of velocity with no spatial encoding other than slice selection. The technique produces images of velocity versus temporal frequency. In applications where the quantity of interest is the peak velocity and in-plane spatial localization is not required, high SNR images are produced with reduced sensitivity to errors due to slice thickness and motion. The technique was validated using steady and pulsatile flow in a straight tube, and compared to both phase contrast measurements and numerical models using steady flow in a 50% and a 75% cosinusoidal stenosis phantom. Results show that for slices as large as 2 cm and/or undergoing periodic motion, FVE can accurately measure the peak velocity in cases where a distribution of velocities exist.

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Blood Flow Velocity Blood Vessels Computer Simulation Constriction, Pathologic Echocardiography, Doppler Fourier Analysis Humans Image Enhancement Models, Cardiovascular Phantoms, Imaging Pulsatile Flow Reproducibility of Results Sensitivity and Specificity Signal Processing, Computer-Assisted Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Validation Study

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Daniela Galea, M Louis Lauzon, Maria Drangova. 2002. Peak velocity determination using fast Fourier velocity encoding with minimal spatial encoding.. https://doi.org/10.1118/1.1494829

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