title: Dynamic radial projection MRI of inhaled hyperpolarized 3He gas.
abstract: A radial projection sliding-window sequence has been developed for imaging the rapid flow of (3)He gas in human lungs. The short echo time (TE) of the radial sequence lends itself to fast repetition times, and thus allows a rapid update in the image when it is reconstructed with a sliding window. Oversampling in the radial direction combined with angular undersampling can further reduce the time needed to acquire a complete image data set, without significantly compromising spatial resolution. Controlled flow phantom experiments using hyperpolarized (3)He gas exemplify the temporal resolution of the method. In vivo studies on three healthy volunteers, one patient with chronic obstructive pulmonary disease (COPD), and one patient with hemiparalysis of the right diaphragm demonstrate that it is possible to accurately resolve the passage of gas down the trachea and bronchi and into the peripheral lung.
authors.affiliation: Unit of Academic Radiology, University of Sheffield, UK. j.m.wild@sheffield.ac.uk
authors.forename: Jim M
authors.initials: JM
authors.lastname: Wild
authors.forename: Martyn N J
authors.initials: MN
authors.lastname: Paley
authors.forename: Larry
authors.initials: L
authors.lastname: Kasuboski
authors.forename: Andrew
authors.initials: A
authors.lastname: Swift
authors.forename: Stan
authors.initials: S
authors.lastname: Fichele
authors.forename: Neil
authors.initials: N
authors.lastname: Woodhouse
authors.forename: Paul D
authors.initials: PD
authors.lastname: Griffiths
authors.forename: Edwin J R
authors.initials: EJ
authors.lastname: van Beek
mesh_terms: D005583:Fourier Analysis; D006371:Helium; D006801:Humans; D007554:Isotopes; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000503:physiopathology; D011659:Pulmonary Gas Exchange
chemical_list: D007554:Isotopes; D006371:Helium