2007/07/23 by Leo L. Tsai, R. W. Mair, Tsai, L. L. +9
Chemistry · Physics and Astronomy · #Advanced NMR Techniques and Applications #Atomic and Subatomic Physics Research #FOS: Physical sciences #Medical Physics (physics.med-ph) #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.0707.3455
openalex publication_date 2007/07/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The human lung and its functions are extremely sensitive to orientation and posture, and debate continues as to the role of gravity and the surrounding anatomy in determining lung function and heterogeneity of perfusion and ventilation. However, study of these effects is difficult. The conventional high-field magnets used for most hyperpolarized 3He MRI of the human lung, and most other common radiological imaging modalities including PET and CT, restrict subjects to lying horizontally, minimizing most gravitational effects. In this paper, we briefly review the motivation for posture-dependent studies of human lung function, and present initial imaging results of human lungs in the supine and vertical body orientations using inhaled hyperpolarized 3He gas and an open-access MRI instrument. The open geometry of this MRI system features a "walk-in" capability that permits subjects to be imaged in vertical and horizontal positions, and potentially allows for complete rotation of the orientation of the imaging subject in a two-dimensional plane. Initial results include two-dimensional lung images acquired with ~ 4 mm in-plane resolution and three-dimensional images with ~ 1.5 cm slice thickness. Effects of posture variation are observed.