T2 relaxation makes an important contribution to tissue contrast in magnetic resonance (MR) imaging. Many tissues are known to exhibit multicomponent T2 relaxation that suggests some compartmental segregation of mobile protons on a T2 timescale. Magnetization transfer (MT) is another relaxation mech
Magnetization transfer contrast (MTC) and tissue water proton relaxation in vivo
β Scribed by Steven D. Wolff; Robert S. Balaban
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 547 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0740-3194
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β¦ Synopsis
In this study the exchange between 'H magnetization in "free" water ( 'Hf) and that in a pool with restricted motion (' H,) was observed in tissues in vivo using NMR saturation transfer methods. Exchange between these two pools was demonstrated by a decrease in the steady-state magnetization and relaxation times of 'Hf with radiofrequency irradiation of 'H,. The pseudo-first-order rate constant for the movement of magnetization from 'Hfto 'H, was -I s-' in kidney and -3 s-' in skeletal muscle in vivo. Proton NMR imaging demonstrated that this exchange was tissue specific and generated a novel form of NMR image contrast. The extent of exchange between 'Hf and 'H, as well as the topological correlation ofthe exchange with relaxation weighted images suggests that this pathway is a major determinant of the observed relaxation properties of water 'H in ViVO.
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