Design of k-space channel combination kernels and integration with parallel imaging

Magn Reson Med. 2014 Jun;71(6):2139-54. doi: 10.1002/mrm.24883. Epub 2013 Aug 13.

Abstract

Purpose: In this work, a new method is described for producing local k-space channel combination kernels using a small amount of low-resolution multichannel calibration data. Additionally, this work describes how these channel combination kernels can be combined with local k-space unaliasing kernels produced by the calibration phase of parallel imaging methods such as GRAPPA, PARS and ARC.

Methods: Experiments were conducted to evaluate both the image quality and computational efficiency of the proposed method compared to a channel-by-channel parallel imaging approach with image-space sum-of-squares channel combination.

Results: Results indicate comparable image quality overall, with some very minor differences seen in reduced field-of-view imaging. It was demonstrated that this method enables a speed up in computation time on the order of 3-16X for 32-channel data sets.

Conclusion: The proposed method enables high quality channel combination to occur earlier in the reconstruction pipeline, reducing computational and memory requirements for image reconstruction.

Keywords: channel combination; channel compression; direct virtual coil; k-space kernel; parallel imaging.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Algorithms*
  • Artifacts
  • Brain Mapping / methods
  • Calibration
  • Contrast Media
  • Humans
  • Image Enhancement / methods*
  • Image Processing, Computer-Assisted / methods
  • Magnetic Resonance Imaging / methods*
  • Phantoms, Imaging
  • Reproducibility of Results

Substances

  • Contrast Media