title: Agents for polarization enhancement in MRI.
abstract: The intrinsic low sensitivity of the NMR phenomenon can be overcome thanks to hyperpolarization procedures that break the limits of the Boltzmann equilibrium and may increase the NMR signal by a factor of 10(5). Hyperpolarization procedures have been applied to enhance the signal from noble gases, such as 3He and 129Xe, and small 13C-containing molecules. For the latter class, attention has been focused on the use of methods based on dynamic nuclear polarization (DNP) and para-hydrogen induced polarization (PHIP). After discussion of the basics of the methods, an overview of the main applications with 13C-containing molecules is presented. This includes pre-clinical MR investigations of vascular imaging, perfusion and catheter tracking as well as molecular imaging protocols that allow the development of highly innovative studies in the field of metabolic imaging.
authors.affiliation: Dipartimento di Chimica I.F.M, Università degli Studi di Torino, V. P. Giuria 7, 10125, Torino, Italy. silvio.aime@unito.it
authors.forename: Silvio
authors.initials: S
authors.lastname: Aime
authors.forename: Walter
authors.initials: W
authors.lastname: Dastrù
authors.forename: Roberto
authors.initials: R
authors.lastname: Gobetto
authors.forename: Daniela
authors.initials: D
authors.lastname: Santelia
authors.forename: Alessandra
authors.initials: A
authors.lastname: Viale
mesh_terms: D000818:Animals; D002247:Carbon Isotopes / Q000737:chemistry; D002404:Catheterization; D003287:Contrast Media / Q000737:chemistry*; D005740:Gases; D006371:Helium / Q000737:chemistry; D006801:Humans; D006859:Hydrogen / Q000737:chemistry; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging / Q000379:methods; D053783:Magnetic Resonance Imaging, Interventional; D008956:Models, Chemical; D015336:Molecular Probe Techniques; D014978:Xenon / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D003287:Contrast Media; D005740:Gases; D006371:Helium; D014978:Xenon; D006859:Hydrogen