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

doi:10.1016/0730-725X(93)90418-D

Magnetic Resonance Imaging

Volume 11, Issue 1, 1993, Pages 107-118

https://doi.org/10.1016/0730-725X(93)90418-D Get rights and content

Abstract

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 $6384$ 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.

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Citation Excerpt :
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Original contributionIn vivo quantification of brain metabolites by 1H-MRS using water as an internal standard

Abstract

J. Magn. Reson.

Biochem. Biophys. Acta

J. Magn. Reson.

Magn. Reson. Imaging

Localized in vivo proton spectroscopy in the brain of patients with multiple sclerosis

Magn. Reson. Med.

A critical assessment of methods of measuring metabolite concentrations by NMR spectroscopy

NMR Biomed.

Localized proton NMR spectroscopy in different regions of the human brain in vivo. Relaxation times and concentration of cerebral metabolites

Magn. Reson. Med.

Localized high-resolution proton NMR spectroscopy using stimulated echoes: Initial applications to human brain in vivo

Magn. Reson. Med.

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