Abstract:
PURPOSE:High field T2* -weighted MR images of the cerebral cortex are increasingly used to study tissue susceptibility changes related to aging or pathologies. This paper presents a novel automated method for the computation of quantitative cortical measures and group-wise comparison using 7 Tesla T2* -weighted magnitude and phase images. METHODS:The cerebral cortex was segmented using a combination of T2* -weighted magnitude and phase information and subsequently was parcellated based on an anatomical atlas. Local gray matter (GM)/white matter (WM) contrast and cortical profiles, which depict the magnitude or phase variation across the cortex, were computed from the magnitude and phase images in each parcellated region and further used for group-wise comparison. Differences in local GM/WM contrast were assessed using linear regression analysis. Regional cortical profiles were compared both globally and locally using permutation testing. The method was applied to compare a group of 10 young volunteers with a group of 15 older subjects. RESULTS:Using local GM/WM contrast, significant differences were revealed in at least 13 of 17 studied regions. Highly significant differences between cortical profiles were shown in all regions. CONCLUSION:The proposed method can be a useful tool for studying cortical changes in normal aging and potentially in neurodegenerative diseases. Magn Reson Med 74:240-248, 2015. © 2014 Wiley Periodicals, Inc.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Doan NT,van Rooden S,Versluis MJ,Buijs M,Webb AG,van der Grond J,van Buchem MA,Reiber JHC,Milles Jdoi
10.1002/mrm.25397subject
Has Abstractpub_date
2015-07-01 00:00:00pages
240-248issue
1eissn
0740-3194issn
1522-2594journal_volume
74pub_type
杂志文章abstract:PURPOSE:To improve the imaging quality of vessel walls with an endoesophageal Wireless Amplified NMR Detector (WAND). METHODS:A cylindrically shaped double-frequency resonator has been constructed with a single metal wire that is self-connected by a pair of nonlinear capacitors. The double-frequency resonator can conv...
journal_title:Magnetic resonance in medicine
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更新日期:2021-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2004-02-01 00:00:00
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更新日期:2009-10-01 00:00:00
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更新日期:2009-06-01 00:00:00
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更新日期:2015-05-01 00:00:00
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