title: 3He lung imaging in an open access, very-low-field human magnetic resonance imaging system.
abstract: The human lung and its functions are extremely sensitive to gravity; however, the conventional high-field magnets used for most laser-polarized (3)He MRI of the human lung restrict subjects to lying horizontally. Imaging of human lungs using inhaled laser-polarized (3)He gas is demonstrated in an open-access very-low-magnetic-field (<5 mT) MRI instrument. This prototype device employs a simple, low-cost electromagnet, with an open geometry that allows variation of the orientation of the imaging subject in a two-dimensional plane. As a demonstration, two-dimensional lung images were acquired with 4-mm in-plane resolution from a subject in two orientations: lying supine and sitting in a vertical position with one arm raised. Experience with this prototype device will guide optimization of a second-generation very-low-field imager to enable studies of human pulmonary physiology as a function of subject orientation.
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 59, Cambridge, Massachusetts 02138, USA. rmair@cfa.harvard.edu
authors.forename: R W
authors.initials: RW
authors.lastname: Mair
authors.forename: M I
authors.initials: MI
authors.lastname: Hrovat
authors.forename: S
authors.initials: S
authors.lastname: Patz
authors.forename: M S
authors.initials: MS
authors.lastname: Rosen
authors.forename: I C
authors.initials: IC
authors.lastname: Ruset
authors.forename: G P
authors.initials: GP
authors.lastname: Topulos
authors.forename: L L
authors.initials: LL
authors.lastname: Tsai
authors.forename: J P
authors.initials: JP
authors.lastname: Butler
authors.forename: F W
authors.initials: FW
authors.lastname: Hersman
authors.forename: R L
authors.initials: RL
authors.lastname: Walsworth
mesh_terms: D000280:Administration, Inhalation; D004867:Equipment Design; D006371:Helium; D006801:Humans; D007554:Isotopes; D008168:Lung / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011187:Posture
chemical_list: D007554:Isotopes; D006371:Helium