Fat quantification using multiecho sequences with bipolar gradients: Investigation of accuracy and noise performance
Article first published online: 14 FEB 2013
Copyright © 2013 Wiley Periodicals, Inc.
Magnetic Resonance in Medicine
Volume 71, Issue 1, pages 219–229, January 2014
How to Cite
Peterson, P. and Månsson, S. (2014), Fat quantification using multiecho sequences with bipolar gradients: Investigation of accuracy and noise performance. Magn Reson Med, 71: 219–229. doi: 10.1002/mrm.24657
- Issue published online: 17 DEC 2013
- Article first published online: 14 FEB 2013
- Manuscript Accepted: 3 JAN 2013
- Manuscript Revised: 20 DEC 2012
- Manuscript Received: 5 OCT 2012
- Magnus Bergvalls stiftelse, Direktör Albert Påhlssons stiftelse
- fat quantification;
- magnetic resonance imaging;
- bipolar gradient;
- eddy currents;
- chemical shift
To investigate the accuracy and noise performance of fat quantification with multiple gradient-echo images acquired using bipolar read-out gradients and compare them with those of the well-established unipolar technique.
The bipolar read-out technique induces phase and amplitude errors caused by gradient delays, eddy currents, and frequency-dependent coil sensitivity. In this study, these errors were corrected for jointly with the fat/water separation by modeling the impact of these effects on the signal. This approach did not require acquisition of reference data or modification of the pulse sequence.
Simulations and a phantom experiment were used to investigate the accuracy and noise performance of the technique and compare them with those of a well-established technique using unipolar read-out gradients. Also, the in vivo feasibility was demonstrated for abdominal applications.
The phantom experiment demonstrated similar accuracy of the bipolar and unipolar fat quantification techniques. In addition, the noise performance was shown not to be affected by the added estimations of the phase and amplitude errors for most inter-echo times.
The bipolar technique was found to provide accurate fat quantification with noise performance similar to the unipolar technique given an appropriate choice of inter-echo time. Magn Reson Med 71:219–229, 2014. © 2013 Wiley Periodicals, Inc.