Observation of coupled 1H metabolite resonances at long TE.
Journal Article (Journal Article)
A PRESS localization (1)H MRS acquisition sequence with a Carr-Purcell train of refocusing pulses (CP-PRESS) has been implemented using global refocusing "sandwich" pulses. The CP pulse train minimized the effects of J-coupled dephasing in metabolites with strongly coupled, multiplet resonance groups as demonstrated in both phantom data and in vivo single-voxel spectroscopy in normal volunteers. Metabolites with multiplet resonance patterns were maintained with greater signal to noise and a simpler resonance pattern at long echo times. T(2) decay times for metabolites with singlet and multiplet resonances were similar to published values, except for the NAA multiplet at 2.5 ppm, which had a significantly shorter T(2) value (147 ms) than that typically reported for the singlet at 2.01 ppm. Metabolite-nulled spectra were acquired in normal volunteers to evaluate the effects of CP-PRESS on baseline signal contributions from residual water, lipids, and macromolecules. The T(2) decay times in four baseline regions in data acquired with the CP-PRESS sequence showed longer decays than corresponding regions in metabolite-nulled spectra from a standard PRESS sequence, but were significantly diminished long before the metabolites of interest were gone. The spectral analysis for spectra with longer TE times also showed less variability due the higher metabolite SNR, simpler spectral patterns, and the decreased baseline contributions.
Full Text
Duke Authors
Cited Authors
- Soher, BJ; Pattany, PM; Matson, GB; Maudsley, AA
Published Date
- June 2005
Published In
Volume / Issue
- 53 / 6
Start / End Page
- 1283 - 1287
PubMed ID
- 15906305
Pubmed Central ID
- PMC1361280
International Standard Serial Number (ISSN)
- 0740-3194
Digital Object Identifier (DOI)
- 10.1002/mrm.20491
Language
- eng
Conference Location
- United States