This article was published online on 19 Jan 2011. Errors were subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 14 Feb 2011.
Combining phase images from multi-channel RF coils using 3D phase offset maps derived from a dual-echo scan†
Article first published online: 19 JAN 2011
Copyright © 2011 Wiley-Liss, Inc.
Magnetic Resonance in Medicine
Volume 65, Issue 6, pages 1638–1648, June 2011
How to Cite
Robinson, S., Grabner, G., Witoszynskyj, S. and Trattnig, S. (2011), Combining phase images from multi-channel RF coils using 3D phase offset maps derived from a dual-echo scan. Magn Reson Med, 65: 1638–1648. doi: 10.1002/mrm.22753
- Issue published online: 17 MAY 2011
- Article first published online: 19 JAN 2011
- Manuscript Accepted: 17 NOV 2010
- Manuscript Revised: 5 OCT 2010
- Manuscript Received: 29 JAN 2010
- Vienna Spots of Excellence Program of the Center of Innovation and Technology, City of Vienna (ZIT)
- phase imaging;
- multi-channel coils;
- phase offsets;
A method is presented for the combination of phase images from multi-channel RF coils in the absence of a volume reference coil. It is based on the subtraction of 3D phase offset maps from the phase data from each coil. Phase offset maps are weighted combinations of phase measurements at two echo times. Multi-Channel Phase Combination using measured 3D phase offsets (MCPC-3D) offers a conceptually and computationally simple solution to the calculation of combined phase images. The dual-echo data required for the phase maps can be intrinsic to the high-resorlution gradient-echo scan to be reconstructed (MCPC-3D-I). Alternatively, a separate, fast, low-resolution dual-echo scan can be used (MCPC-3D-II). Both variants are shown to give near perfect phase matching, yielding images with high SNR throughout and high GM-WM contrast. MCPC-3D is compared with other reference-free phase image crombination methods; high-pass phase filtering, phase difference imaging, and matching using constant offsets (MCPC-C). Multi-Channel Phase Combination using measured 3D phase offsets method does not need an overlap between the signals from individual coils and can be used with parallel imaging, making it ideally suited to multi-channel coils with a large number of elements, and to high and ultra-high field systems. Magn Reson Med, 2011. © 2011 Wiley-Liss, Inc.