Signal enhancement through heteronuclear polarisation transfer in in-vivo 31P MR spectroscopy of the human brain

Weber-Fahr, W., Bachert, P., Henn, F. A., Braus, D. F., Ende, G. (July 2003) Signal enhancement through heteronuclear polarisation transfer in in-vivo 31P MR spectroscopy of the human brain. MAGMA, 16 (2). pp. 68-76. ISSN 0968-5243 (Print)0968-5243 (Linking)

Abstract

Significant (31)P NMR signal enhancement through heteronuclear polarisation transfer was obtained in model solutions and in vivo on a 1.5-T whole-body MR scanner equipped with two RF channels. The much higher population differences involved in proton Zeeman energy levels can be transferred to the (31)P levels with the refocused INEPT (insensitive nucleus enhancement by polarisation transfer) double-resonance experiment by means of a series of simultaneously applied broadband RF pulses. INEPT achieves a polarisation transfer from (1)H to (31)P spin states by directly reordering the populations in spin systems with heteronuclear scalar coupling. Thus, only the (31)P NMR signal of metabolites with scalar (1)H-(31)P coupling is amplified, while the other metabolite signals in the spectra are suppressed. Compared to Ernst-angle excitation, a repetition-time-dependent signal enhancement of eta=(29+/-3)% for methylene diphosphonic acid (MDPA) and eta=(56+/-1)% for phosphorylethanolamine (PE) was obtained on model solutions through optimisation of the temporal parameters of the pulse experiment. The results are in good agreement with numerical calculations of the theoretical model for the studied spin systems. With optimised echo times, in-vivo (31)P signal enhancement of the same order was obtained in studies of the human brain.

Item Type: Paper
Uncontrolled Keywords: Brain/ metabolism Diphosphonates/analysis Ethanolamines/analysis Humans Nuclear Magnetic Resonance, Biomolecular/ methods Phosphorus/ diagnostic use/ metabolism Reproducibility of Results Sensitivity and Specificity Signal Processing, Computer-Assisted
Subjects: Investigative techniques and equipment
organs, tissues, organelles, cell types and functions > organs types and functions > brain
Investigative techniques and equipment > spectroscopy > magnetic resonance spectroscopy
Investigative techniques and equipment > spectroscopy
CSHL Authors:
Communities: CSHL labs > Henn lab
Depositing User: Matt Covey
Date: July 2003
Date Deposited: 11 Jun 2013 19:51
Last Modified: 11 Jun 2013 19:51
Related URLs:
URI: https://repository.cshl.edu/id/eprint/27964

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