Three-Dimensional Spectroscopic Imaging with Time-Varying Gradients

Department of Electrical Engineering, Stanford University, California, USA.
Magnetic Resonance in Medicine (Impact Factor: 3.4). 04/1995; 33(4):461-6. DOI: 10.1002/mrm.1910330402
Source: PubMed

ABSTRACT A spectroscopic imaging sequence with a time-varying readout gradient in the slice selection direction is used to image multiple contiguous slices. For a given voxel size, the imaging time and signal-to-noise ratio of the three-dimensional spectroscopic sequence are the same as for a single slice acquisition without the oscillating readout gradient. The data reconstruction employs a gridding algorithm in two dimensions to interpolate the nonuniformly sampled data onto a Cartesian grid, and a fast Fourier transform in four dimensions: three spatial dimensions and the spectral dimension. The method is demonstrated by in vivo imaging of NAA in human brain at 1.5 T with 10 slices of 16 x 16 pixels spectroscopic images acquired in a total scan time of 17 min.

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