Abstract:
:Myelin water fraction (MWF) images in brain tend to be spatially noisy with unknown or no apparent spatial patterns structure, so values are therefore typically averaged over large white matter (WM) volumes. We investigated the existence of an inherent spatial structure in MWF maps and explored the benefits of examining MWF values along diffusion tensor imaging (DTI)-derived white matter tracts. We compared spatial anisotropy between MWF and the more widely-used fractional anisotropy (FA) measure. Sixteen major white matter fibre bundles were extracted based on DTI data from 41 healthy subjects. MWF coefficients of variation (CoV) were computed in sub-segments along each fibre tract and compared to MWF CoVs from the surrounding "tubes" - i.e. voxels just exterior to the tract - of each segment. We further assessed the consistency of the MWF along fibre bundles across subjects and investigated the benefit of examining MWF values in sections along each fibre bundle rather than integrating over the whole tract. CoVs of MWF and FA were lower in fibre bundles compared to their enclosing tubes in all investigated tracts. Both measures possessed a spatial gradient of CoV that was smaller aligned along, compared to perpendicular to, the fibre bundles. All WM tracts showed MWF profiles along their trajectory that were consistent across subjects and were more accurate than the mean overall fibre MWF value in estimating ages of the subjects. We conclude that, although less obvious visually, the spatial MWF distribution in white matter consistently follows a distinct pattern along underlying fibre bundles across subjects. Assessing MWF in sections along white matter tracts may provide a sensitive and robust way to assess myelin across subjects.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Baumeister TR,Kolind SH,MacKay AL,McKeown MJdoi
10.1016/j.mri.2019.09.012subject
Has Abstractpub_date
2020-04-01 00:00:00pages
33-42eissn
0730-725Xissn
1873-5894pii
S0730-725X(19)30340-6journal_volume
67pub_type
杂志文章abstract::The successful use of magnetic resonance imaging (MRI) of a moldic fossil dicynodont from the Permian aeolian Hopeman Sandstone Formation of Elgin, Scotland, UK, provides paleontologists with a nondestructive technique for examining fossils preserved in this fashion. For large moldic fossils, medical scanners such as ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2003.09.006
更新日期:2004-02-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2007-07-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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doi:10.1016/j.mri.2008.02.006
更新日期:2008-11-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2018-06-01 00:00:00
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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更新日期:2017-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(89)90706-6
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journal_title:Magnetic resonance imaging
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更新日期:1993-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.01.007
更新日期:2004-04-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(96)00021-5
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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更新日期:2014-04-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(91)90429-p
更新日期:1991-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90371-6
更新日期:1992-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.10.006
更新日期:2018-02-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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更新日期:2018-11-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(91)90007-9
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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