title: A two-pool model to describe the IVIM cerebral perfusion.
abstract: IntraVoxel Incoherent Motion (IVIM) is a magnetic resonance imaging (MRI) technique capable of measuring perfusion-related parameters. In this manuscript, we show that the mono-exponential model commonly used to process IVIM data might be challenged, especially at short diffusion times. Eleven rat datasets were acquired at 7T using a diffusion-weighted pulsed gradient spin echo sequence with b-values ranging from 7 to 2500 s/mm2at three diffusion times. The IVIM signals, obtained by removing the diffusion component from the raw MR signal, were fitted to the standard mono-exponential model, a bi-exponential model and the Kennan model. The Akaike information criterion used to find the best model to fit the data demonstrates that, at short diffusion times, the bi-exponential IVIM model is most appropriate. The results obtained by comparing the experimental data to a dictionary of numerical simulations of the IVIM signal in microvascular networks support the hypothesis that such a bi-exponential behavior can be explained by considering the contribution of two vascular pools: capillaries and somewhat larger vessels.
authors.affiliation: 1 NeuroSpin, CEA Saclay-Center, Gif-sur-Yvette, France.|2 INRIA Saclay, Palaiseau, France.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Fournet
authors.affiliation: 2 INRIA Saclay, Palaiseau, France.
authors.forename: Jing-Rebecca
authors.initials: JR
authors.lastname: Li
authors.affiliation: 3 Bioengineering Department, Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Alex M
authors.initials: AM
authors.lastname: Cerjanic
authors.affiliation: 3 Bioengineering Department, Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Bradley P
authors.initials: BP
authors.lastname: Sutton
authors.affiliation: 1 NeuroSpin, CEA Saclay-Center, Gif-sur-Yvette, France.
authors.forename: Luisa
authors.initials: L
authors.lastname: Ciobanu
authors.affiliation: 1 NeuroSpin, CEA Saclay-Center, Gif-sur-Yvette, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Le Bihan
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D008954:Models, Biological; D011919:Rats, Inbred Strains
keywords: Cerebral blood flow; intravoxel incoherent motion; magnetic resonance imaging; microcirculation; perfusion