The magnetic field dependence of the water-proton spin-lattice relaxation rate (1/T(1)) in tissues results from magnetic coupling to the protons of the rotationally immobilized components of the tissue. As a consequence, the magnetic field dependence of the water-proton (1/T(1)) is a scaled report o
The magnetic field dependence of proton spin relaxation in tissues
โ Scribed by Robert G. Bryant; Daniel Ari Mendelson; Cathy Coolbaugh Lester
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 627 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0740-3194
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
The magnetic field dependence of waterโproton relaxation is reported for a simple protein solution, a crossโlinked protein solution, and a series of rat tissues, fresh, dried and rehydrated. The shape of the magnetic field dependence associated with water proton relaxation in tissues is accounted for by magnetic dipoleโdipole interactions between the mobile water spins and the immobile spin populations of the nonrotating components of the tissue coupling the behavior of the immobilized spin system to that of the mobile water spin system. The effect of this coupling is to impart the field dependence of the relaxation associated with the immobilized spin population to that of the mobile water spins that are observed in most relaxation and imaging experiments. ยฉ 1991 Academic Press, Inc.
๐ SIMILAR VOLUMES
## Abstract A molecular theory is presented for the fieldโdependent spinโlattice relaxation time of water in tissue. The theory attributes the large relaxation enhancement observed at low frequencies to intermediary protons in labile groups or internal water molecules that act as relaxation sinks f
The proton spin-spin rebxation time for liquid chloroform has been measured over the temperature range -54" to +9O"C. The values of Ta(H) decrease with increasing temperature contrary to the behavior obsemed for Tr (H). Values of Tz (I-l) calculated from experimental values of Tr (H) and Tz(Cl) repr
The magnetic field dependence of the water proton T, is calculated for aqueous solutions of nitroxides based on a detailed analysis of early T, measurements on nitroxide solutions made as a function of magnetic field. The results parallel those for TI closely and, unlike metal systems, the implicati
## Abstract Since contrast in magnetic resonance imaging (MRI) is so sensitive to the magnetic relaxation rates of tissue protons, the use of paramagnetic ions to alter contrast in a tissueโspecific fashion is an alluring prospect. The influence of these ions on the proton relaxation rates in homog