Feasibility of internally referenced brain temperature imaging with a metabolite signal

Magn Reson Med Sci. 2003 Apr 1;2(1):17-22. doi: 10.2463/mrms.2.17.


The feasibility of using a metabolite signal as an internal reference for self-referenced temperature distribution measurement was examined. Line scan echo-planar spectroscopic imaging (LSEPSI) was applied to obtain quick multi-voxel spectroscopic measurements and to avoid possible spectral degradation from motion. Temperature distribution in a rabbit brain in vivo was successfully visualized by means of the chemical shift of water, which was measured by using naturally abundant (up to 10 mM) N-acetyl-aspartate (NAA) as the reference signal. Unlike the phase-mapping approach, this technique does not require a pixel-by-pixel subtraction. Therefore, in theory, it is more resistant to inter-scan motion or changes in susceptibility. The spatial and temporal resolutions of this technique are 1.5 cm3 and 4.5 min. A higher signal-to-noise ratio and optimization of the water and outer-volume suppression capabilities will be required to further enhance the temperature-mapping capabilities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / metabolism
  • Body Temperature*
  • Body Water*
  • Brain / metabolism*
  • Echo-Planar Imaging / methods*
  • Feasibility Studies
  • Magnetic Resonance Spectroscopy / methods*
  • Phantoms, Imaging
  • Protons
  • Rabbits
  • Time Factors


  • Protons
  • Aspartic Acid
  • N-acetylaspartate