title: In vivo MRI using real-time production of hyperpolarized 129Xe.
abstract: MR imaging of hyperpolarized (HP) nuclei is challenging because they are typically delivered in a single dose of nonrenewable magnetization, from which the entire image must be derived. This problem can be overcome with HP (129)Xe, which can be produced sufficiently rapidly to deliver in dilute form (1%) continuously and on-demand. We demonstrate a real-time in vivo delivery of HP (129)Xe mixture to rats, a capability we now routinely use for setting frequency, transmitter gain, shimming, testing pulse sequences, scout imaging, and spectroscopy. Compared to images acquired using conventional fully concentrated (129)Xe, real-time (129)Xe images have 26-fold less signal, but clearly depict ventilation abnormalities. Real-time (129)Xe MRI could be useful for time-course studies involving acute injury or response to treatment. Ultimately, real-time (129)Xe MRI could be done with more highly concentrated (129)Xe, which could increase the signal-to-noise ratio by 100 relative to these results to enable a new class of gas imaging applications.
authors.affiliation: Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA. driehuys@orion.duhs.duke.edu
authors.forename: Bastiaan
authors.initials: B
authors.lastname: Driehuys
authors.forename: Jim
authors.initials: J
authors.lastname: Pollaro
authors.forename: Gary P
authors.initials: GP
authors.lastname: Cofer
mesh_terms: D000818:Animals; D003199:Computer Systems; D008279:Magnetic Resonance Imaging; D051381:Rats; D011916:Rats, Inbred F344; D013057:Spectrum Analysis; D014979:Xenon Isotopes
chemical_list: D014979:Xenon Isotopes