title: Transverse relaxivity of particulate MRI contrast media: from theories to experiments.
abstract: Computer simulations and experimental approach have been used to characterize the properties of particulate MRI contrast agents with special attention paid to the influence of particle size. Up to approximately 50 nm, an increase of the particle diameter leads to a strong enhancement of the transverse magnetization decay rate. For larger grains or aggregates, the decay rate measured without spin-echo formation reaches a plateau. When observed through a spin-echo sequence, the transverse magnetization decay rate becomes slower on increasing the particle size or on shortening the echo time. For these large particles, multiexponential decay rates are observed. Definition and measurement of relaxivity in such systems is discussed.
authors.affiliation: Department of Organic Chemistry, University of Mons-Hainaut, Belgium.
authors.forename: R N
authors.initials: RN
authors.lastname: Muller
authors.forename: P
authors.initials: P
authors.lastname: Gillis
authors.forename: F
authors.initials: F
authors.lastname: Moiny
authors.forename: A
authors.initials: A
authors.lastname: Roch
mesh_terms: D003198:Computer Simulation; D003287:Contrast Media; D006801:Humans; D008279:Magnetic Resonance Imaging; D009010:Monte Carlo Method; D010316:Particle Size
chemical_list: D003287:Contrast Media