Abstract:
PURPOSE:To test the efficacy of 7T MRS for in vivo detection of 2-hydroxyglutarate (2HG) in brain tumors. METHODS:The subecho times of point-resolved spectroscopy (PRESS) were optimized at 7T with density-matrix simulations and phantom validation to improve the 2HG signal selectivity with respect to the neighboring resonances of γ-aminobutyric acid (GABA), glutamate (Glu), and glutamine (Gln). MRS data were acquired from 12 subjects with gliomas in vivo and analyzed with LCModel using calculated basis spectra. Metabolite levels were quantified using unsuppressed short echo time (TE) water as a reference. RESULTS:The PRESS TE was optimized as TE = 78 ms (TE1 = 58 ms and TE2 = 20 ms), at which the 2HG 2.25 ppm resonance appeared as a temporally maximum inverted narrow peak and the GABA, Glu, and Gln resonances between 2.2 and 2.5 ppm were all positive peaks. The PRESS TE = 78 ms method offered improved discrimination of 2HG from Glu, Gln, and GABA when compared with short-TE MRS. 2HG was detected in all patients enrolled in the study, the estimated 2HG concentrations ranging from 1.0 to 6.2 mM, with percentage standard deviation of 2%-7%. CONCLUSION:Data indicate that the optimized MRS provides good selectivity of 2HG from other metabolite signals and may confer reliable in vivo detection of 2HG at relatively low concentrations. Magn Reson Med 77:936-944, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Ganji SK,An Z,Tiwari V,McNeil S,Pinho MC,Pan E,Mickey BE,Maher EA,Choi Cdoi
10.1002/mrm.26190subject
Has Abstractpub_date
2017-03-01 00:00:00pages
936-944issue
3eissn
0740-3194issn
1522-2594journal_volume
77pub_type
杂志文章abstract:PURPOSE:To test octafluorocyclobutane (OFCB) as an inhalation contrast agent for fluorine-19 MRI of the lung, and to compare the image quality of OFCB scans with perfluoropropane (PFP) scans THEORY AND METHODS: After normalizing for the number of signal averages, a theoretical comparison between the OFCB signal-to-nois...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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abstract::Functional magnetic resonance imaging (fMRI) has become the most widely used modality for visualizing regional brain activation in response to sensorimotor or cognitive tasks. While the majority of fMRI studies have used blood oxygenation level-dependent (BOLD) contrast as a marker for neural activation, baseline drif...
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更新日期:2007-10-01 00:00:00
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更新日期:2011-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2010-02-01 00:00:00
abstract::The effects of macroscopic background field gradients upon 2D gradient echo images of inhaled (3)He in the human lung were investigated at 1.5 T. Effective compensation of in-slice signal loss in (3)He gradient echo images was then demonstrated using a multiple acquisition interleaved single gradient echo sequence. Th...
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更新日期:2003-08-01 00:00:00
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更新日期:2019-06-01 00:00:00
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更新日期:2014-07-01 00:00:00
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更新日期:2016-03-01 00:00:00
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更新日期:1993-03-01 00:00:00
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更新日期:2001-08-01 00:00:00
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更新日期:1991-12-01 00:00:00
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更新日期:2017-05-01 00:00:00
abstract:PURPOSE:To test and implement a motion-robust and respiratory-resolved 3D Radial Flow framework that addresses the need for rapid, high resolution imaging in neonatal patients with congenital heart disease. METHODS:A 4-point velocity encoding and 3D radial trajectory with double-golden angle ordering was combined with...
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更新日期:2020-02-01 00:00:00
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更新日期:2015-12-01 00:00:00