title: Detection of myocardial capillary orientation with intravascular iron-oxide nanoparticles in spin-echo MRI.
abstract: In mammalian hearts the capillaries are closely aligned with the muscle fibers. We report our observation of a main-field direction-dependent contrast in MR spin-echo (SE) images of the heart in the presence of Ferumoxtran-10, an intravascular iron-oxide nanoparticle contrast agent (CA). We describe a novel MRI method for mapping the preferential orientation of capillaries in the myocardial wall. The eigenvector corresponding to the minimum eigen value of the R2 relaxation rate tensor is consistent with the expected orientation of the capillary network. Preliminary results also demonstrate the feasibility of this method for in vivo application to rodent imaging.
authors.affiliation: Laboratory of Cardiac Energetics, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-1061, USA.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Vignaud
authors.forename: Ignacio
authors.initials: I
authors.lastname: Rodriguez
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Ennis
authors.forename: Ranil
authors.initials: R
authors.lastname: DeSilva
authors.forename: Peter
authors.initials: P
authors.lastname: Kellman
authors.forename: Joni
authors.initials: J
authors.lastname: Taylor
authors.forename: Eric
authors.initials: E
authors.lastname: Bennett
authors.forename: Han
authors.initials: H
authors.lastname: Wen
mesh_terms: D000818:Animals; D002196:Capillaries / Q000033:anatomy & histology*; D003287:Contrast Media; D003331:Coronary Vessels / Q000033:anatomy & histology*; D003911:Dextrans; D004285:Dogs; D052203:Ferrosoferric Oxide; D007501:Iron; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D049329:Nanostructures; D010087:Oxides; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; C097921:ferumoxtran-10; D007501:Iron; D052203:Ferrosoferric Oxide