Details

Autor(en) / Beteiligte

• Christiansen, P.
• Henriksen, O.
• Stubgaard, M.
• Gideon, P.
• Larsson, H.B.W.

Titel

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

Ist Teil von

• Magnetic resonance imaging, 1993, Vol.11 (1), p.107-118

Ort / Verlag

New York, NY: Elsevier Inc

Erscheinungsjahr

1993

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• 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.