title: Real-time 3D MRI of contrast agents in whole living mice.
abstract: A specific mouse whole body coil and a dedicated gradient system at 4.7 T were coupled with an ultra-fast 3D gradient echo MRI and keyhole reconstruction technique to obtain 3D whole-body dynamic T(1)-weighted or T(2)*-weighted imaging. The technique was used to visualize the real-time distribution of non-targeting T(1) and T(2)* contrast agent (CA) in a glioma-bearing mouse model. T(1) dynamic contrast-enhancement imaging was performed with a fast imaging with steady-state precession sequence [echo time/repetition time (TE/TR), 1.32/3.7 ms] before and after CA injection (Gd-DOTA and BSA-Gd-DOTA) for 21 min. The temporal resolution was 1 image/6.5 s. T(2)* imaging (TE/TR, 4/8 ms) was performed before and after iron-based (small and ultra-small particles of iron oxide) CA injection for 45 min. The temporal resolution was 1 image/14 s. Signal-to-noise ratio curves were determined in various mouse organs. The whole-body coil and gradient systems made it possible to acquire data with sufficient and homogeneous signal-to-noise ratio on the whole animal. The spatial resolution allowed adequate depiction of the major organs, blood vessels and brain glioma. The distribution and the time-course of T(1) and T(2)* contrasts upon contrast agent injection were also assessed. 3D whole-body mouse MRI is feasible at high spatial resolution in movie mode and can be applied successfully to visualize real-time contrast agent distribution. This method should be effective in future preclinical molecular imaging studies.
authors.affiliation: Centre de Résonance Magnétique des Systèmes biologiques, UMR 5536, CNRS/Université Victor Segalen Bordeaux 2, 146, rue Léo Saignat 33076 Bordeaux Cedex, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Bled
authors.forename: Wadie Ben
authors.initials: WB
authors.lastname: Hassen
authors.forename: Line
authors.initials: L
authors.lastname: Pourtau
authors.forename: Philippe
authors.initials: P
authors.lastname: Mellet
authors.forename: Titus
authors.initials: T
authors.lastname: Lanz
authors.forename: Dorothee
authors.initials: D
authors.lastname: Schüler
authors.forename: Pierre
authors.initials: P
authors.lastname: Voisin
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Franconi
authors.forename: Eric
authors.initials: E
authors.lastname: Thiaudière
authors.forename: Sylvain
authors.initials: S
authors.lastname: Miraux
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005910:Glioma / Q000175:diagnosis; D006571:Heterocyclic Compounds / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008819:Mice, Nude; D009942:Organometallic Compounds / Q000737:chemistry
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C000499:ferric oxide; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate