Effects of diffusion on magnetic resonance imaging of laser-polarized xenon gas
| Autor: | Bhima Sheridan, Thomas M. de Swiet, Boyd M. Goodson, Alexander Pines, Yi-Qiao Song |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Boundary detection
Physics Molecular diffusion Condensed matter physics medicine.diagnostic_test General Physics and Astronomy chemistry.chemical_element Magnetic resonance imaging Magnetic field gradient Polarization (waves) Laser Molecular physics law.invention Xenon chemistry law medicine Physical and Theoretical Chemistry |
| Zdroj: | The Journal of Chemical Physics. 108:6233-6239 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.476030 |
| Popis: | Molecular diffusion during the application of magnetic field gradients can distort magnetic resonance images. A systematic characterization of these distortions in one dimension was performed using highly spin-polarized xenon gas. By varying the strength of the applied gradient and the geometric dimension of the sample, the evolution of these image distortions between the regimes of strong and weak diffusion was observed. These results are compared with numerical simulations. By directly measuring the displacement distribution of the polarized xenon atoms, it is shown that in the weak-diffusion regime the image distortions originate from the restricted diffusive motion near the sample boundaries, in agreement with previous theoretical work. Additionally, it is shown that the effects of diffusion can be utilized to enhance the contrast between the boundaries and bulk in the images of polarized gas samples, and thus may be exploited as a means of boundary detection in such systems. |
| Databáze: | OpenAIRE |
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