Abstract:
:We describe a doubly tuned radiofrequency (RF) local coil probe designed specifically for performing in vivo image-localized spectroscopy. The probe was designed using principles developed in connection with the counter-rotating-current (CRC) and planar-pair loop gap resonators for magnetic resonance imaging (MRI). The probe design satisfies several criteria useful for in vivo 1H/31P experiments at 1.5 T. First, sensitivity on the low-frequency mode is preserved relative to a singly tuned coil. This result was confirmed by bench-test and in vitro MR experimental data. Second, through principles of intrinsic decoupling the probe is isolated from any externally applied uniform excitation field, which is desirable for in vivo 1H imaging and solvent suppression. Third, the regions of sensitivity of the high- and low-frequency modes of the coil are similar, and therefore spectroscopic volumes of interest identified on an image will reflect the same volumes as those selected during spectroscopy. Finally, interface to the MR system is such that the high- or low-frequency circuits may be selected entirely under software control, with no requirement for changing coils or cables or moving the subject.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Grist TM,Jesmanowicz A,Kneeland JB,Froncisz W,Hyde JSdoi
10.1002/mrm.1910060303subject
Has Abstractpub_date
1988-03-01 00:00:00pages
253-64issue
3eissn
0740-3194issn
1522-2594journal_volume
6pub_type
杂志文章abstract::The aim of this study was to detect salvageable peri-infarction myocardium by MRI in rats after infarction, using with a double contrast agent (CA) protocol at 7 Tesla. Intravascular superparamagnetic iron oxide (SPIO) nanoparticles and an extracellular paramagnetic CA (Gd-DOTA) were used to characterize the peri-infa...
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abstract:PURPOSE:To demonstrate the feasibility of imaging a bolus of co-polarized [1-13 C]pyruvate and 13 C-urea to simultaneously assess both metabolism and perfusion in the rodent heart. METHODS:Copolarized [1-13 C]pyruvate and 13 C-urea was imaged using a multi-echo, flow-sensitized spiral pulse sequence. Healthy rats were...
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更新日期:2021-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1991-10-01 00:00:00
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更新日期:2008-10-01 00:00:00
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更新日期:2016-10-01 00:00:00
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更新日期:2010-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2011-04-01 00:00:00
abstract:PURPOSE:To develop and evaluate a method for volumetric contrast-enhanced MRI of the liver, with high spatial and temporal resolutions, for combined dynamic imaging and MR angiography (MRA) using a single injection of contrast agent. METHODS:An interleaved variable density (IVD) undersampling pattern was implemented i...
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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