Abstract:
:Using a 32-echo imaging pulse sequence, T2 relaxation decay curves were acquired from five white- and six gray-matter brain structures outlined in 12 normal volunteers. The water contents of white and gray matter were 0.71 (0.01) and 0.83 (0.03) g/ml, respectively. All white-matter structures had significantly higher myelin water percentages (signal percentage with T2 between 10 and 50 ms) than all gray-matter structures. The range in geometric mean T2 of the main peak for both white and gray matter was from 70 to 86 ms. T2 distributions from the posterior internal capsules and splenium of the corpus callosum were significantly wider (width is related to water environment inhomogeneity) than those from any other white- or gray-matter structures. Thus, quantitative measurement and analysis of T2 relaxation reveals differences in brain tissue water environments not discernible on conventional MR images. These differences may make short T2 components reliable markers for normal myelin.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Whittall KP,MacKay AL,Graeb DA,Nugent RA,Li DK,Paty DWdoi
10.1002/mrm.1910370107subject
Has Abstractpub_date
1997-01-01 00:00:00pages
34-43issue
1eissn
0740-3194issn
1522-2594journal_volume
37pub_type
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