2D axial moving table acquisitions with dynamic slice adaptation

Magn Reson Med. 2006 Feb;55(2):423-30. doi: 10.1002/mrm.20779.

Abstract

A method for axial multi-slice imaging during continuous table motion has been developed and implemented on a clinical scanner. Multiple axial slice packages are acquired consecutively and combined to cover an extended longitudinal FOV. To account for the table motion during the acquisition, the RF pulse frequencies are continuously updated according to the actual table velocity and slice position. Different strategies for the spatial-temporal acquisition sequence with extended FOV are proposed. They cover different regimes of scan requirements regarding table velocity, used scan range, and slice resolution. The method is easy to implement and compatible with most kinds of sequences. The robustness of the proposed approach has been tested in phantom studies and healthy volunteers using T1-, T2-, and STIR-weighted multi-slice techniques that are based on gradient and turbo spin echo sequences and compared to a stationary approach usually used in clinical routine. The method provides artifact free gradient echo based images during continuous table motion, while for turbo spin echo sequences limitations in choosing table translations occur due to gradient non-linearity effects.

MeSH terms

  • Algorithms
  • Artifacts
  • Feasibility Studies
  • Humans
  • Image Enhancement / methods*
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging / instrumentation
  • Magnetic Resonance Imaging / methods*
  • Motion
  • Phantoms, Imaging