Abstract:
:An in vitro study was performed to investigate the effects of B(o) inhomogeneity on magnetic resonance images of flow. Controlled inhomogeneity gradients (Gi) were applied and the magnitude of the artifacts produced was quantified for different echo delay times (TE). Both steady and pulsatile flows were examined. In the presence of an inhomogeneity gradient, signal loss is apparent if the flow is pulsatile and/or if the slice thickness is large. The signal loss increases with increasing TE and Gi. With pulsatile flow, ghosting artifacts are also generated. These increase in intensity with increasing TE and Gi. In vivo, field inhomogeneity due to susceptibility variations is large enough to produce these effects. Representative time-of-flight images obtained of a normal volunteer with two different TEs demonstrate the effect in vivo. Flow-related signal loss and artifacts, therefore, increase with increasing TE independent of the moments of the applied gradients.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Drangova M,Pelc NJdoi
10.1002/mrm.1910350116subject
Has Abstractpub_date
1996-01-01 00:00:00pages
126-30issue
1eissn
0740-3194issn
1522-2594journal_volume
35pub_type
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2017-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2004-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2017-02-01 00:00:00
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更新日期:2004-06-01 00:00:00
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更新日期:2007-06-01 00:00:00
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更新日期:1993-09-01 00:00:00
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更新日期:2014-02-01 00:00:00
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更新日期:2019-04-01 00:00:00
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更新日期:2003-08-01 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2012-11-01 00:00:00
abstract::An arterial spin labeling technique using separate RF labeling and imaging coils was used to obtain multislice perfusion images of the human brain at 3 T. Continuous RF irradiation at a peak power of 0.3 W was applied to the carotid arteries to adiabatically invert spins. Labeling was achieved without producing magnet...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199906)41:6<1093::aid-mrm4
更新日期:1999-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2018-02-01 00:00:00
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doi:10.1002/mrm.21585
更新日期:2008-06-01 00:00:00
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更新日期:2014-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910200218
更新日期:1991-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21010
更新日期:2006-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910390506
更新日期:1998-05-01 00:00:00
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更新日期:2002-02-01 00:00:00
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更新日期:2001-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1993-02-01 00:00:00
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更新日期:2002-06-01 00:00:00
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更新日期:2018-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:2002-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25799
更新日期:2016-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2001-03-01 00:00:00
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pub_type: 杂志文章
doi:10.1002/mrm.21683
更新日期:2008-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
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更新日期:2005-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1002/mrm.25713
更新日期:2016-04-01 00:00:00