B0 mapping using rewinding trajectories (BMART)

Magn Reson Med. 2017 Aug;78(2):664-669. doi: 10.1002/mrm.26391. Epub 2016 Aug 24.

Abstract

Purpose: To create a B0 map and correct for off-resonance with minimal scan time increase for two-dimensional (2D) or 3D non-Cartesian acquisitions.

Methods: Rewinding trajectories that bring the zeroth gradient moment to zero every repetition time (TR) were used to estimate the off-resonance with a center-out 3D cones trajectory, which required an increase in the minimum TR by 5%. The off-resonance estimation and correction was implemented using an algorithm based on binning and object-domain phase correction. B0 maps using BMART (B0 mapping using rewinding trajectories) were compared to maps obtained using separate scans with multiple echo time (TE) in a phantom and human brain.

Results: Excellent agreement between BMART and the multiple-TE method were observed, and images corrected with BMART were deblurred.

Conclusion: BMART can correct for off-resonance without requiring an additional scan, and can be easily applied to center-out or projection trajectories (2D or 3D). Magn Reson Med 78:664-669, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Keywords: B0 map; deblurring; non-Cartesian; off-resonance correction.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Algorithms
  • Brain / diagnostic imaging
  • Computer Simulation
  • Humans
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Phantoms, Imaging