title: Diffusion imaging of whole, post-mortem human brains on a clinical MRI scanner.
abstract: Diffusion imaging of post mortem brains has great potential both as a reference for brain specimens that undergo sectioning, and as a link between in vivo diffusion studies and "gold standard" histology/dissection. While there is a relatively mature literature on post mortem diffusion imaging of animals, human brains have proven more challenging due to their incompatibility with high-performance scanners. This study presents a method for post mortem diffusion imaging of whole, human brains using a clinical 3-Tesla scanner with a 3D segmented EPI spin-echo sequence. Results in eleven brains at 0.94 × 0.94 × 0.94 mm resolution are presented, and in a single brain at 0.73 × 0.73 × 0.73 mm resolution. Region-of-interest analysis of diffusion tensor parameters indicate that these properties are altered compared to in vivo (reduced diffusivity and anisotropy), with significant dependence on post mortem interval (time from death to fixation). Despite these alterations, diffusion tractography of several major tracts is successfully demonstrated at both resolutions. We also report novel findings of cortical anisotropy and partial volume effects.
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK. Electronic address: karla@fmrib.ox.ac.uk.
authors.forename: Karla L
authors.initials: KL
authors.lastname: Miller
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Charlotte J
authors.initials: CJ
authors.lastname: Stagg
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Gwenaëlle
authors.initials: G
authors.lastname: Douaud
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Saad
authors.initials: S
authors.lastname: Jbabdi
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Smith
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Timothy E J
authors.initials: TEJ
authors.lastname: Behrens
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Jenkinson
authors.affiliation: Clinical Neurology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Chance
authors.affiliation: Clinical Neurology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Esiri
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Natalie L
authors.initials: NL
authors.lastname: Voets
authors.affiliation: Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK.
authors.forename: Ned
authors.initials: N
authors.lastname: Jenkinson
authors.affiliation: Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK.
authors.forename: Tipu Z
authors.initials: TZ
authors.lastname: Aziz
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Martin R
authors.initials: MR
authors.lastname: Turner
authors.affiliation: FMRIB Centre, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
authors.forename: Heidi
authors.initials: H
authors.lastname: Johansen-Berg
authors.affiliation: A.A.Martinos Centre, Massachusetts General Hospital, Boston, USA.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: McNab
mesh_terms: D016880:Anisotropy; D016477:Artifacts; D001344:Autopsy; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D016707:Tissue Fixation