Center-out echo-planar spectroscopic imaging with correction of gradient-echo phase and time shifts
Article first published online: 27 JUL 2012
Copyright © 2012 Wiley Periodicals, Inc.
Magnetic Resonance in Medicine
How to Cite
Labadie, C., Hetzer, S., Schulz, J., Mildner, T., Aubert-Frécon, M. and Möller, H. E. (2012), Center-out echo-planar spectroscopic imaging with correction of gradient-echo phase and time shifts. Magn Reson Med. doi: 10.1002/mrm.24428
- Article first published online: 27 JUL 2012
- Manuscript Accepted: 2 JUL 2012
- Manuscript Revised: 29 JUN 2012
- Manuscript Received: 27 MAR 2012
- EU (fast-mrs.eu MRTN-CT-2006-035801)
- echo-planar spectroscopic imaging;
- center-out trajectory;
- gradient-echo phase correction;
- gradient acoustic frequency
A procedure to prevent the formation of image and spectral Nyquist ghosts in echo-planar spectroscopic imaging is introduced. It is based on a novel Cartesian center-out echo-planar spectroscopic imaging trajectory, referred to as EPSICO, and combined with a correction of the gradient-echo phase and time shifts. Processing of homogenous sets of forward and reflected echoes is no longer necessary, resulting in an optimized spectral width. The proposed center-out trajectory passively prevents the formation of Nyquist ghosts by privileging the acquisition of the center k-space line with forward echoes at the beginning of an echo-planar spectroscopic imaging dwell time and by ensuring that all k-space lines and their respective complex conjugates are acquired at equal time intervals. With the proposed procedure, concentrations of N-acetyl aspartate, creatine, choline, glutamate, and myo-inositol were reliably determined in human white matter at 3 T. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.