A simple method for investigating the effects of non-uniformity of radiofrequency transmission and radiofrequency reception in MRI.
- 1 January 1998
- journal article
- Published by Oxford University Press (OUP) in The British Journal of Radiology
- Vol. 71 (841) , 59-67
- https://doi.org/10.1259/bjr.71.841.9534700
Abstract
Inhomogeneity of the transmitted or received B1 field leads to intensity variations in MR images and spatial dependence in apparent concentration in MR spectra. We describe a simple method for investigating such variations. The transmitted B1 field can be measured both in vivo and in vitro which allows investigation of sample dependent effects that can not be measured on phantoms. For homogeneous regions the method also allows the received B1 field to be measured both in vivo and in vitro. Our method uses only a standard spin echo pulse sequence and simple region of interest analysis and should be implementable on any commercial scanner. The method is demonstrated using a variety of transmission and reception radiofrequency coils both in vivo and in vitro.Keywords
This publication has 7 references indexed in Scilit:
- Sources of intensity nonuniformity in spin echo images at 1.5 TMagnetic Resonance in Medicine, 1994
- Standing Waves in Uniform Water PhantomsJournal of Magnetic Resonance, Series B, 1994
- Mapping of the Radiofrequency FieldJournal of Magnetic Resonance, Series A, 1993
- Stimulated Echoes and Spin Echoes. Simultaneous Determination of T2, Diffusion Coefficient, and RF HomogeneityJournal of Magnetic Resonance, Series B, 1993
- Correction of intensity nonuniformity in MR images of any orientationMagnetic Resonance Imaging, 1993
- Radiofrequency map of an NMR coil by imagingMagnetic Resonance Imaging, 1993
- Image non-uniformity in magnetic resonance imaging: its magnitude and methods for its correctionThe British Journal of Radiology, 1987