Observation of coupled 1H metabolite resonances at long TE.

Published

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

  • 15906305

International Standard Serial Number (ISSN)

  • 0740-3194

Digital Object Identifier (DOI)

  • 10.1002/mrm.20491

Language

  • eng

Conference Location

  • United States