Quick Search:

uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive 

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-56450

Giese, D; Haeberlin, M; Barmet, C; Pruessmann, K P; Schaeffter, T; Kozerke, S (2012). Analysis and correction of background velocity offsets in phase-contrast flow measurements using magnetic field monitoring. Magnetic Resonance in Medicine, 67(5):1294-1302.

[img]Published Version
PDF (Article in press) - Registered users only
1297Kb

Abstract

The value of phase-contrast magnetic resonance imaging for quantifying tissue motion and blood flow has been long recognized. However, the sensitivity of the method to system imperfections can lead to inaccuracies limiting its clinical acceptance. A key source of error relates to eddy current-induced phase fluctuations, which can offset the measured object velocity significantly. A higher-order dynamic field camera was used to study the spatiotemporal evolution of background phases in cine phase-contrast measurements. It is demonstrated that eddy current-induced offsets in phase-difference data are present up to the second spatial order. Oscillatory temporal behaviors of offsets in the kHz range suggest mechanical resonances of the MR system to be non-negligible in phase-contrast imaging. By careful selection of the echo time, their impact can be significantly reduced. When applying field monitoring data for correcting eddy current and mechanically induced velocity offsets, errors decrease to less than 0.5% of the maximum velocity for various sequence settings proving the robustness of the correction approach. In vivo feasibility is demonstrated for aortic and pulmonary flow measurements in five healthy subjects. Using field monitoring data, mean error in stroke volume was reduced from 10% to below 3%. Magn Reson Med, 2011. © 2011 Wiley-Liss, Inc.

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > Institute of Biomedical Engineering
DDC:170 Ethics
610 Medicine & health
Language:English
Date:2012
Deposited On:22 Jan 2012 21:24
Last Modified:08 Dec 2013 12:08
Publisher:Wiley-Blackwell
ISSN:0740-3194
Publisher DOI:10.1002/mrm.23111
PubMed ID:21826731
Citations:Web of Science®. Times Cited: 4
Google Scholar™

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page