Abstract:
:An automated retrospective image registration based on mutual information is adapted to a multislice functional magnetic resonance imaging (fMRI) acquisition protocol to provide accurate motion correction. Motion correction is performed by mapping each slice to an anatomic volume data set acquired in the same fMRI session to accommodate inter-slice head motion. Accuracy of the registration parameters was assessed by registration of simulated MR data of the known truth. The widely used rigid body volume registration approach based on stacked slices from the time series data may hinder statistical accuracy by introducing inaccurate assumptions of no motion between slices for multislice fMRI data. Improved sensitivity and specificity of the fMRI signal from mapping-each-slice-to-volume method is demonstrated in comparison with a stacked-slice correction method by examining functional data from two normal volunteers. The data presented in a standard anatomical coordinate system suggest the reliability of the mapping-each-slice-to-volume method to detect the activation signals consistent between the two subjects.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kim B,Boes JL,Bland PH,Chenevert TL,Meyer CRdoi
10.1002/(sici)1522-2594(199905)41:5<964::aid-mrm16subject
Has Abstractpub_date
1999-05-01 00:00:00pages
964-72issue
5eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(199905)41:5<964::AID-MRM16journal_volume
41pub_type
杂志文章abstract:PURPOSE:To develop a three-dimensional, free-breathing, late gadolinium enhancement (3D FB-LGE) cardiovascular magnetic resonance (CMR) technique, and to compare it with clinically used two-dimensional breath-hold LGE (2D BH-LGE). METHODS:The proposed 3D FB-LGE method consisted of inversion preparation, inversion dela...
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:1997-09-01 00:00:00
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更新日期:2018-11-01 00:00:00
abstract::Measurements of the volume magnetic susceptibility of solids using the classical Gouy balance approach are hampered by variations in apparent density of the packed powder. In this paper a quantitative NMR measurement of the volume magnetic susceptibility of powdered solids is described and the volume susceptibility of...
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更新日期:1997-04-01 00:00:00
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更新日期:2007-11-01 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:2014-02-01 00:00:00
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更新日期:2016-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:2015-01-01 00:00:00
abstract:PURPOSE:To test the hypothesis that a noninvasive dynamic contrast enhanced MRI (DCE-MRI) derived interstitial volume fraction (ve ) and/or distribution volume (VD ) were correlated with tumor cellularity in cerebral tumor. METHODS:T1 -weighted DCE-MRI studies were performed in 18 athymic rats implanted with U251 xeno...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.24873
更新日期:2014-06-01 00:00:00
abstract::A receive-only phased-array coil was designed to image the lower extremities. The array consists of four volume coils placed on two cylindrical formers. The coil array has the ability to image both legs simultaneously over a 40 cm longitudinal field of view (FOV). Experiments using phantoms show an increase in signal-...
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更新日期:2004-03-01 00:00:00
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更新日期:2018-03-01 00:00:00
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更新日期:2011-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1990-08-01 00:00:00
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更新日期:1987-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2014-09-01 00:00:00
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更新日期:2013-05-01 00:00:00
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更新日期:2021-01-01 00:00:00
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更新日期:2017-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199909)42:3<461::aid-mrm8>
更新日期:1999-09-01 00:00:00