Three-dimensional spectroscopic imaging with time-varying gradients

Magn Reson Med. 1995 Apr;33(4):461-6. doi: 10.1002/mrm.1910330402.

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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Algorithms
  • Brain / metabolism*
  • Fourier Analysis
  • Humans
  • Image Processing, Computer-Assisted*
  • Magnetic Resonance Spectroscopy* / methods
  • Signal Processing, Computer-Assisted*
  • Time Factors