In vivo quantification of brain metabolites by 1H-MRS using water as an internal standard

Magn Reson Imaging. 1993;11(1):107-18. doi: 10.1016/0730-725x(93)90418-d.


The reliability of absolute quantification of average metabolite concentrations in the human brain in vivo by 1H-MRS using the fully relaxed water signal as an internal standard was tested in a number of in vitro as well as in vivo measurements. The experiments were carried out on a SIEMENS HELICON SP 63/84 wholebody MR-scanner operating at 1.5 T using a STEAM sequence. In vitro studies indicate a very high correlation between metabolite signals (area under peaks) and concentration, R = 0.99 as well as between metabolite signals and the volume of the selected voxel, R = 1.00. The error in quantification of N-acetyl aspartate (NAA) concentration was about 1-2 mM (6-12%). Also in vivo a good linearity between water signal and selected voxel size was seen. The same was true for the studied metabolites, N-acetyl aspartate (NAA), creatine/phosphocreatine (Cr/PCr), and choline (Cho). Calculated average concentrations of NAA, Cr/PCr, and Cho in the occipital lobe of the brain in five healthy volunteers were (mean +/- 1 SD) 11.6 +/- 1.3 mM, 7.6 +/- 1.4 mM, and 1.7 +/- 0.5 mM. The results indicate that the method presented offers reasonable estimation of metabolite concentrations in the brain in vivo and therefore is useful in clinical research.

MeSH terms

  • Body Water / metabolism*
  • Brain / metabolism*
  • Evaluation Studies as Topic
  • Humans
  • Hydrogen
  • In Vitro Techniques
  • Magnetic Resonance Spectroscopy / instrumentation
  • Magnetic Resonance Spectroscopy / methods*
  • Mathematics
  • Models, Structural
  • Reference Values
  • Time Factors


  • Hydrogen