Abstract:
:Formalin fixation of tissue is a common laboratory practice. A direct comparison of diffusion tensor imaging (DTI) parameters from mouse brains before (in vivo) and after (ex vivo) formalin fixation is reported herein. Five diffusion indices were examined in a cohort of seven mice: relative anisotropy (RA), directional correlation (DC), trace (Tr(D)), trace-normalized axial diffusivity (D(axially)), and radial diffusivity (D(radially)). Seven regions of interest (ROIs), including five in white matter and two in gray matter, were selected for examination. Consistent with previous findings, a significant decrease of Tr(D) was observed for all ROIs after fixation. However, water diffusion anisotropy, as defined by the indices RA, DC, D(axially), and D(radially), remained unchanged after fixation. Thus, fixation does not appear to alter diffusion anisotropy in the mouse brain. This finding supports the utility of diffusion anisotropy analysis of fixed tissue. The combination of DTI measurements and standard histology may shed light on the microstructural determinants of diffusion anisotropy in normal and disease states.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Sun SW,Neil JJ,Song SKdoi
10.1002/mrm.10605subject
Has Abstractpub_date
2003-10-01 00:00:00pages
743-8issue
4eissn
0740-3194issn
1522-2594journal_volume
50pub_type
杂志文章abstract:PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25420
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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abstract::Diffusion tensor imaging (DTI) is a new imaging modality that can provide unique information on brain white matter anatomy. Measurements of water diffusion constant along multiple axes are fitted to a tensor model, from which the diffusion anisotropy and dominant fiber orientation can be estimated. Even though the ten...
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更新日期:2005-04-01 00:00:00
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更新日期:2003-09-01 00:00:00
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更新日期:2012-03-01 00:00:00
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更新日期:2011-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910360311
更新日期:1996-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1999-07-01 00:00:00
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doi:10.1002/mrm.1910300606
更新日期:1993-12-01 00:00:00
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doi:10.1002/mrm.25528
更新日期:2015-11-01 00:00:00
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更新日期:2019-09-01 00:00:00
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更新日期:2001-06-01 00:00:00
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更新日期:2017-09-01 00:00:00
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更新日期:2006-10-01 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:2011-09-01 00:00:00
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更新日期:1991-12-01 00:00:00
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更新日期:2020-11-16 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:2020-11-01 00:00:00