In vivo 1H NMR spectroscopy of rat brain at 1 ms echo time.

Details

Serval ID
serval:BIB_523E03FE00F1
Type
Article: article from journal or magazin.
Collection
Publications
Title
In vivo 1H NMR spectroscopy of rat brain at 1 ms echo time.
Journal
Magnetic Resonance in Medicine
Author(s)
Tkác I., Starcuk Z., Choi I.Y., Gruetter R.
ISSN
0740-3194 (Print)
ISSN-L
0740-3194
Publication state
Published
Issued date
1999
Volume
41
Number
4
Pages
649-656
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.Publication Status: ppublish
Abstract
Using optimized, asymmetric radiofrequency (RF) pulses for slice selection, the authors demonstrate that stimulated echo acquisition mode (STEAM) localization with ultra-short echo time (1 ms) is possible. Water suppression was designed to minimize sensitivity to B1 inhomogeneity using a combination of 7 variable power RF pulses with optimized relaxation delays (VAPOR). Residual water signal was well below the level of most observable metabolites. Contamination by the signals arising from outside the volume of interest was minimized by outer volume saturation using a series of hyperbolic secant RF pulses, resulting in a sharp volume definition. In conjunction with FASTMAP shimming (Gruetter Magn Reson Med 1993;29: 804-811), the short echo time of 1 msec resulted in highly resolved in vivo 1H nuclear magnetic resonance spectra. In rat brain the water linewidths of 11-13 Hz and metabolite singlet linewidths of 8-10 Hz were measured in 65 microl volumes. Very broad intense signals (delta v(1/2) > 1 kHz), as expected from membranes, for example, were not observed, suggesting that their proton T2 are well below 1 msec. The entire chemical shift range of 1H spectrum was observable, including resolved resonances from alanine, aspartate, choline group, creatine, GABA, glucose, glutamate, glutamine, myo-inositol, lactate, N-acetylaspartate, N-acetylaspartylglutamate, phosphocreatine, and taurine. At 9.4 T, peaks close to the water were observed, including the H-1 of alpha-D-glucose at 5.23 ppm and a tentative H-1 resonance of glycogen at 5.35 ppm.
Keywords
Animals, Brain Chemistry, Glucose/analysis, Glutamates/analysis, Magnetic Resonance Spectroscopy/methods, Rats
Pubmed
Web of science
Create date
04/08/2010 16:28
Last modification date
03/03/2018 17:13
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