Publications [#132765] of G. Allan Johnson
- XJ Chen, HE Möller, MS Chawla, GP Cofer, B Driehuys, LW Hedlund, JR MacFall, GA Johnson, Spatially resolved measurements of hyperpolarized gas properties in the lung in vivo. Part II: T *(2).,
Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine, UNITED STATES, vol. 42 no. 4
pp. 729-37, ISSN 0740-3194
(last updated on 2005/08/03)
The transverse relaxation time, T *(2), of hyperpolarized (HP) gas in the lung in vivo is an important parameter for pulse sequence optimization and image contrast. We obtained T *(2) maps of HP (3)He and (129)Xe in guinea pig lungs (n = 17) and in human lungs. Eight different sets of (3)He guinea pig studies were acquired, with variation of slice selection, tidal volume, and oxygen level. For example, for a (3)He tidal volume of 3 cm(3) and no slice selection, the average T *(2) in the trachea was 14.7 ms and 8.0 ms in the intrapulmonary airspaces. The equivalent (129)Xe experiment yielded an average T *(2) of 40.8 ms in the trachea and 18.5 ms in the intrapulmonary airspaces. The average (3)He T *(2) in the human intrapulmonary airspaces was 9.4 ms. The relaxation behavior was predicted by treating the lung as a porous medium, resulting in good agreement between estimated and measured T *(2) values in the intrapulmonary airspaces. Magn Reson Med 42:729-737, 1999.
Animals • Guinea Pigs • Helium • Humans • Isotopes • Lung • Magnetic Resonance Imaging • Male • Middle Aged • Pulmonary Diffusing Capacity • Trachea • Xenon Isotopes • anatomy & histology • anatomy & histology* • diagnostic use • methods*