Fast multi-voxel two-dimensional spectroscopic imaging at 3T

Department of Radiology, University of California-San Francisco, San Francisco, CA, USA.
Magnetic Resonance Imaging (Impact Factor: 2.09). 11/2007; 25(8):1155-61. DOI: 10.1016/j.mri.2007.01.118
Source: PubMed


The utility of multivoxel two-dimensional chemical shift imaging in the clinical environment will ultimately be determined by the imaging time and the metabolite peaks that can be detected. Different k-space sampling schemes can be characterized by their minimum required imaging time. The use of spiral-based readout gradients effectively reduces the minimum scan time required due to simultaneous data acquisition in three k-space dimensions (k(x), k(y) and k(f(2))). A 3-T spiral-based multivoxel two-dimensional spectroscopic imaging sequence using the PRESS excitation scheme was implemented. Good performance was demonstrated by acquiring preliminary in vivo data for applications, including brain glutamate imaging, metabolite T(2) quantification and high-spatial-resolution prostate spectroscopic imaging. All protocols were designed to acquire data within a 17-min scan time at a field strength of 3 T.

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Available from: Daniel M Spielman, Oct 01, 2014
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