Signal loss and absolute quantitation errors in 1H-MRS (localized proton MR spectroscopy) because of physiologic brain motion are analyzed quantitatively. Cardiac and respiratory related motion lead to substantial phase dispersion when using a standard, short echo-time STEAM sequence. The loss in si
Frame-by-frame PRESS 1H-MRS of the brain at 3 T: The effects of physiological motion
✍ Scribed by Rachel Katz-Brull; Robert E. Lenkinski
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 136 KB
- Volume
- 51
- Category
- Article
- ISSN
- 0740-3194
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
^1^H‐MRS at high field has been increasingly utilized to study brain metabolism in healthy and pathological states. The aim of this work was to determine the effects of physiological motion on the results of this exam in the presence of the increased susceptibility differences at high field. Single voxel spectra of various regions in the human brain were acquired using frame‐by‐frame PRESS ^1^H‐MRS at a 0.5 Hz sampling rate. The frame‐by‐frame variations of the FID phase and the frequency and fractional amplitude variations of the residual water‐signal were analyzed. In the human brain the standard deviations of these variations were 3.9 ± 0.5°, 0.83 ± 0.32 Hz, and 0.028 ± 0.013 of the mean amplitude (n = 15). In a motionless phantom, smaller phase and frequency variations were detected in water‐suppressed acquisitions. However, the end effects of physiological motion on PRESS ^1^H‐MRS of the brain at 3 T were negligible. Magn Reson Med 51:184–187, 2004. © 2003 Wiley‐Liss, Inc.
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