## Abstract We present an analysis of how flow oblique to the frequencyβencoding direction generates displacement artifacts in MR imaging and show that for flow which has constant velocity between the start of the phase encoding and the center of the echo it is possible to eliminate these artifacts
Pulsatile flow artifacts in 3D magnetic resonance imaging
β Scribed by Lawrence R. Frank; Richard B. Buxton; Charles W; Kerber
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 954 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0740-3194
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β¦ Synopsis
Abstract
Some of the important features of how pulsatile flow generates artifacts in threeβdimensional magnetic resonance imaging are analyzed and demonstrated. Time variations in the magnetic resonance signal during the heart cycle lead to more complex patterns of artifacts in 3D imaging than in 2D imaging. The appearance and location of these artifacts within the image volume are shown to be describable as displacements along a line in a plane parallel to that defined by the phase and volume encode directions. The angle of the line in the plane depends solely upon the imaging parameters while the ghost displacement along the line is proportional to the signal modulation frequency. Aliasing of these ghosts leads to a variety of artifact patterns which are sensitive to the pulsation period and repetition time of the pulse sequence. Numerical simulations of these effects were found to be in good agreement with experimental images of an elastic model of a human carotid artery under simulated physiological conditions and with images of two human subjects.
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