We describe an experimental approach that combines multidimensional NMR experiments with a steadily renewed source of laser-polarized 129 Xe. Using a continuous flow system to circulate the gas mixture, gas phase NMR signals of laser-polarized 129 Xe can be observed with an enhancement of three to f
Brain MRI with laser-polarized 129xe
β Scribed by Scott D. Swanson; Matthew S. Rosen; Bernard W. Agranoff; Kevin P. Coulter; Robert C. Welsh; Timothy E. Chupp
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 444 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0740-3194
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β¦ Synopsis
Abstract
The feasibility of brain MRI with laserβpolarized ^129^Xe in a small animal model is demonstrated. Naturally abundant ^129^Xe is polarized and introduced into the lungs of SpragueβDawley rats. Polarized xenon gas dissolves in the blood and is transported to the brain where it accumulates in brain tissue. Spectroscopic studies reveal a single, dominant, tissueβphase NMR resonance in the head at 194.5 ppm relative to the gas phase resonance. Images of ^129^Xe in the rat head were obtained with 98βΞΌl voxels by 2D chemical shift imaging and show that xenon is localized to the brain. This work establishes that nuclear polarization produced in the gas phases survives transport to the brain where it may be imaged. Increases in polarization and delivered volume of ^129^Xe will allow clinical measurements of regional cerebral blood flow.
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Laser-polarized noble gases such as 3 He or 129 Xe exhibit a nuclear spin polarization exceeding the equilibrium nuclear spin polarization by orders of magnitude, resulting in a corresponding sensitivity gain in NMR experiments. Recent developments in the application of laser-polarized 129 Xe are re
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