title: A theoretical framework for determining cerebral vascular function and heterogeneity from dynamic susceptibility contrast MRI.
abstract: Mapping the complex heterogeneity of vascular tissue in the brain is important for understanding cerebrovascular disease. In this translational study, we build on previous work using vessel architectural imaging (VAI) and present a theoretical framework for determining cerebral vascular function and heterogeneity from dynamic susceptibility contrast magnetic resonance imaging (MRI). Our tissue model covers realistic structural architectures for vessel branching and orientations, as well as a range of hemodynamic scenarios for blood flow, capillary transit times and oxygenation. In a typical image voxel, our findings show that the apparent MRI relaxation rates are independent of the mean vessel orientation and that the vortex area, a VAI-based parameter, is determined by the relative oxygen saturation level and the vessel branching of the tissue. Finally, in both simulated and patient data, we show that the relative distributions of the vortex area parameter as a function of capillary transit times show unique characteristics in normal-appearing white and gray matter tissue, whereas tumour-voxels in comparison display a heterogeneous distribution. Collectively, our study presents a comprehensive framework that may serve as a roadmap for in vivo and per-voxel determination of vascular status and heterogeneity in cerebral tissue.
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Digernes
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.|2 Department of Physics, University of Oslo, Oslo, Norway.
authors.forename: Atle
authors.initials: A
authors.lastname: Bjørnerud
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
authors.forename: Svein Are S
authors.initials: SAS
authors.lastname: Vatnehol
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
authors.forename: Grete
authors.initials: G
authors.lastname: Løvland
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Courivaud
authors.affiliation: 3 Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.
authors.forename: Einar
authors.initials: E
authors.lastname: Vik-Mo
authors.affiliation: 3 Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.|4 Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Torstein R
authors.initials: TR
authors.lastname: Meling
authors.affiliation: 1 Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
authors.forename: Kyrre E
authors.initials: KE
authors.lastname: Emblem
mesh_terms: D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000378:metabolism; D002196:Capillaries / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003287:Contrast Media; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008954:Models, Biological; D009010:Monte Carlo Method; D010100:Oxygen / Q000378:metabolism
chemical_list: D003287:Contrast Media; D010100:Oxygen
keywords: DSC-MRI; glioma; tumour heterogeneity; vascular modelling; vessel architectural imaging