Self-navigated interleaved spiral (SNAILS): Application to high-resolution diffusion tensor imaging
Article first published online: 23 NOV 2004
Copyright © 2004 Wiley-Liss, Inc.
Magnetic Resonance in Medicine
Volume 52, Issue 6, pages 1388–1396, December 2004
How to Cite
Liu, C., Bammer, R., Kim, D.-h. and Moseley, M. E. (2004), Self-navigated interleaved spiral (SNAILS): Application to high-resolution diffusion tensor imaging. Magn Reson Med, 52: 1388–1396. doi: 10.1002/mrm.20288
- Issue published online: 23 NOV 2004
- Article first published online: 23 NOV 2004
- Manuscript Accepted: 27 JUL 2004
- Manuscript Revised: 12 JUL 2004
- Manuscript Received: 12 MAY 2004
- National Institute of Health. Grant Numbers: NIH-1R01NS35959, NIH-1R01EB2711
- Center of Advanced MR Technology of Stanford. Grant Number: NCRR P41 RR 09784
- Lucas Foundation
- magnetic resonance imaging;
- high resolution;
- diffusion tensor imaging;
- variable density spiral;
- motion correction
A fat-saturated twice-refocused spin echo sequence was implemented on a GE Signa 1.5-T whole-body system for diffusion-weighted imaging. Data were acquired using an analytically designed interleaved variable-density (VD) spiral readout trajectory. This flexible design algorithm allowed real-time prescription on the scanner. Each interleaf of the VD spiral oversampled the center of k-space. The oversampling provided an inherent motion compensation capability. The resultant diffusion-weighted images showed good quality without any retrospective motion correction. An iterated motion correction algorithm was developed to further reduce the signal cancellation artifact caused by motion-induced phase error. In this algorithm, a low-resolution phase map was estimated using the oversampled data in the center of k-space in order to correct for phase error in image space.
In vivo diffusion tensor imaging (DTI) studies were performed on the brains of healthy volunteers. High-quality isotropic diffusion-weighted images, trace maps, and FA maps from axial, sagittal, and coronal slices were obtained using a VD spiral readout trajectory with matrix size 256 × 256. To our knowledge, this was also the first time in vivo 512 × 512 DTI results were reported. Magn Reson Med 52:1388–1396, 2004. © 2004 Wiley-Liss, Inc.