Resolution improvements in in vivo 1H NMR spectra with increased magnetic field strength.
Détails
ID Serval
serval:BIB_246B15679972
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Resolution improvements in in vivo 1H NMR spectra with increased magnetic field strength.
Périodique
Journal of Magnetic Resonance
ISSN
1090-7807 (Print)
ISSN-L
1090-7807
Statut éditorial
Publié
Date de publication
1998
Volume
135
Numéro
1
Pages
260-264
Langue
anglais
Notes
Publication types: Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.Publication Status: ppublish
Résumé
The measurement of cerebral metabolites using highly homologous localization techniques and similar shimming methods was performed in the human brain at 1.5 and 4 T as well as in the dog and rat brain at 9.4 T. In rat brain, improved resolution was achieved by shimming all first- and second-order shim coils using a fully adiabatic FASTMAP sequence. The spectra showed a clear improvement in spectral resolution for all metabolite resonances with increased field strength. Changes in cerebral glutamine content were clearly observed at 4 T compared to 1.5 T in patients with hepatic encephalopathy. At 9.4 T, glutamine H4 at 2.46 ppm was fully resolved from glutamate H4 at 2.37 ppm, as was the potential resonance from gamma-amino-butyric acid at 2.30 ppm and N-acetyl-aspartyl-glutamate at 2.05 ppm. Singlet linewidths were found to be as low as 6 Hz (0.015 ppm) at 9.4 T, indicating a substantial decrease in ppm linewidth with field strength. Furthermore, the methylene peak of creatine was partially resolved from phosphocreatine, indicating a close to 1:1 relationship in gray matter. We conclude that increasing the magnetic field strength increases spectral resolution also for 1H NMR, which can lead to more than linear sensitivity gains.
Mots-clé
Adult, Amino Acids/analysis, Animals, Brain Chemistry, Dogs, Hepatic Encephalopathy/metabolism, Humans, Image Processing, Computer-Assisted, Inositol/analysis, Lactic Acid/analysis, Magnetic Resonance Spectroscopy, Protons, Rats, Reproducibility of Results, Stereoisomerism
Pubmed
Web of science
Création de la notice
04/08/2010 16:28
Dernière modification de la notice
20/08/2019 14:02