๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Effects of acceleration on the accuracy of MR phase velocity measurements

โœ Scribed by John N. Oshinski; David N. Ku; Daryl E. Bohning; Roderic I. Pettigrew

Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
610 KB
Volume
2
Category
Article
ISSN
1053-1807

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โœฆ Synopsis

Abstract

Acceleration in blood flow can affect the accuracy of phase velocity measurements. Convective acceleration is due to changes in flow geometry and is independent of the timeโ€varying acceleration caused by flow pulsatility. To analyze the effects of convective acceleration on flow velocity measurements, phase velocity measurements were obtained in steady laminar flow in the convergent segment of a 90%, hourglassโ€shaped stenosis phantom at a Reynolds number of 1,500. Measurements at the stenosis indicated that convective acceleration caused the measured values of average crossโ€sectional velocity to deviate as much as 37% from the theoretical values. The magnitude of the error could be accounted for by including the convective acceleration term in the phase shift equation. Convective acceleration effects should not be ignored in flow velocity measurements through stenoses, even when timeโ€dependent acceleration due to flow pulsatility can be neglected.

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