Abstract:
:Advances in modern magnetic resonance imaging (MRI) pulse sequences have enabled clinically practical cortical bone imaging. Human cortical bone is known to contain a distribution of T(1) and T(2) components attributed to bound and pore water, although clinical imaging approaches have yet to discriminate bound from pore water based on their relaxation properties. Herein, two clinically compatible MRI strategies are proposed for selectively imaging either bound or pore water by utilizing differences in their T(1)s and T(2)s. The strategies are validated in a population of ex vivo human cortical bones, and estimates obtained for bound and pore water are compared to bone mechanical properties. Results show that the two MRI strategies provide good estimates of bound and pore water that correlate to bone mechanical properties. As such, the strategies for bound and pore water discrimination shown herein should provide diagnostically useful tools for assessing bone fracture risk, once applied to clinical MRI.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Horch RA,Gochberg DF,Nyman JS,Does MDdoi
10.1002/mrm.24186subject
Has Abstractpub_date
2012-12-01 00:00:00pages
1774-84issue
6eissn
0740-3194issn
1522-2594journal_volume
68pub_type
杂志文章abstract::Electron Spin Echo Envelope Modulation (ESEEM) data are reported for three gadolinium (III) chelates, Gd-EDTA, Gd-DTPA, and Gd-TTHA, in frozen D2O/CH3OD glasses. This series includes Gd-DTPA, an MRI contrast agent that is in clinical use. Three-pulse electron spin echo modulation patterns can be modeled to yield geome...
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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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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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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2015-11-01 00:00:00
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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:2008-09-01 00:00:00
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更新日期:2006-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2020-12-08 00:00:00
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