Abstract：
:To demonstrate the feasibility of a novel MR elastography (MRE) technique based on a conventional gradient-echo type multi-echo MR sequence which does not need additional bipolar magnetic field gradients (motion encoding gradient: MEG), yet is sensitive to vibration. In a gradient-echo type multi-echo MR sequence, several images are produced from each echo of the train with different echo times (TEs). If these echoes are synchronized with the vibration, each readout's gradient lobes achieve a MEG-like effect, and the later generated echo causes a greater MEG-like effect. The sequence was tested for the tissue-mimicking agarose gel phantoms and the psoas major muscles of healthy volunteers. It was confirmed that the readout gradient lobes caused an MEG-like effect and the later TE images had higher sensitivity to vibrations. The magnitude image of later generated echo suffered the T2 decay and the susceptibility artifacts, but the wave image and elastogram of later generated echo were unaffected by these effects. In in vivo experiments, this method was able to measure the mean shear modulus of the psoas major muscle. From the results of phantom experiments and volunteer studies, it was shown that this method has clinical application potential.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Numano T,Mizuhara K,Hata J,Washio T,Homma Kdoi
10.1016/j.mri.2014.10.002subject
Has Abstractpub_date
2015-01-01 00:00:00pages
31-7issue
1eissn
0730-725Xissn
1873-5894pii
S0730-725X(14)00309-9journal_volume
33pub_type
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journal_title：Magnetic resonance imaging
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更新日期：2011-05-01 00:00:00
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更新日期：2009-11-01 00:00:00
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更新日期：2017-01-01 00:00:00
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更新日期：2007-10-01 00:00:00
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更新日期：2010-06-01 00:00:00
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更新日期：2019-05-01 00:00:00
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pub_type： 杂志文章,随机对照试验
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更新日期：2011-05-01 00:00:00
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journal_title：Magnetic resonance imaging
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更新日期：2016-06-01 00:00:00
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更新日期：2014-04-01 00:00:00
