## Abstract __J__βcoupled resonances such as lactate exhibit complex behavior in PRESSβlocalized spectroscopy. Polarization transfer effects due to nonideal slice profiles can lead to substantial errors in quantification unless recognized. In this work, it is shown how these effects can be predicte
Calculations and experimental studies of the lineshape of the lactate doublet in PRESS-localized 1H MRS
β Scribed by Ian Marshall; James M. Wild
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 503 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0740-3194
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Accurate quantification of NMR metabolites by spectral modeling requires assumed lineshape functions. For singlet resonances, a combination of Lorentzian and Gaussian lineshapes is sufficient, but for weakly Jβcoupled resonances such as lactate, more complex lineshapes are necessary. In this work, the lactate lineshape is calculated for the PRESS sequence using standard RF pulses, and compared with experimental measurements. A similar comparison is made for PRESSβlocalized spectroscopic imaging, in which the lineshape varies from voxel to voxel across the field of view. These observations have important implications for the quantification of lactate in experimental and human studies.
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Localized 1 H NMR spectroscopy using the 90 β’t 1 -180 β’t 1 + t 2 -180 β’ -t 2 -Acq. PRESS sequence can lead to a signal loss for the lactate doublet compared with signals from uncoupled nuclei which is dependent on the choice of t 1 and t 2 . The most striking signal loss of up to 78% of the total si
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