The present invention has a magnetic resonance spectroscopic imaging
(MRSI) method that allows collecting a complete spectroscopic image with
one spectral dimension and up to three spatial dimensions in a single
signal excitation. The method employs echo-planar spatial-spectral
encoding combined with phase encoding interleaved into the echo-planar
readout train and partial parallel imaging to reconstruct spatially
localized absorption mode spectra. This approach enables flexible
tradeoff between gradient and RF encoding to maximize spectral width and
spatial resolution. Partial parallel imaging (e.g. SENSE or GRAPPA) is
employed with this methodology to accelerate the phase encoding
dimension. A preferred implementation is with the recently developed
superresolution parallel MRI method, which accelerates along both the
readout and phase encoding dimensions and thus enables particularly large
spectral width and spatial resolution. The symmetrical k-space trajectory
of this methodology is designed to compensate phase errors due to
convolution of spatial and spectral encoding. This method is suitable for
hyperpolarized MRSI, spatial mapping of the diffusion coefficients of
biochemicals and functional MRI using quantitative mapping of water
relaxation.