title: Information-based ranking of 10 compartment models of diffusion-weighted signal attenuation in fixed prostate tissue.
abstract: This study compares the theoretical information content of single- and multi-compartment models of diffusion-weighted signal attenuation in prostate tissue. Diffusion-weighted imaging (DWI) was performed at 9.4 T with multiple diffusion times and an extended range of b values in four whole formalin-fixed prostates. Ten models, including different combinations of isotropic, anisotropic and restricted components, were tested. Models were ranked using the Akaike information criterion. In all four prostates, two-component models, comprising an anisotropic Gaussian component and an isotropic restricted component, ranked highest in the majority of voxels. Single-component models, whether isotropic (apparent diffusion coefficient, ADC) or anisotropic (diffusion tensor imaging, DTI), consistently ranked lower than multi-component models. Model ranking trends were independent of voxel size and maximum b value in the range tested (1.6-16 mm(3) and 3000-10,000 s/mm(2)). This study characterizes the two major water components previously identified by biexponential models and shows that models incorporating both anisotropic and restricted components provide more information-rich descriptions of DWI signals in prostate tissue than single- or multi-component anisotropic models and models that do not account for restricted diffusion.
authors.affiliation: College of Engineering and Science, Victoria University, Melbourne, Australia.
authors.forename: Sisi
authors.initials: S
authors.lastname: Liang
authors.affiliation: Center for Medical Image Computing, University College London, London, UK.
authors.forename: Eleftheria
authors.initials: E
authors.lastname: Panagiotaki
authors.affiliation: Mark Wainright Analytical Centre, University of New South Wales, Sydney, Australia.
authors.forename: Andre
authors.initials: A
authors.lastname: Bongers
authors.affiliation: College of Engineering and Science, Victoria University, Melbourne, Australia.
authors.forename: Peng
authors.initials: P
authors.lastname: Shi
authors.affiliation: Department of Urology, Royal Prince Alfred Hospital, School of Medicine, University of Sydney, Sydney, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Sved
authors.affiliation: Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Watson
authors.affiliation: Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, Sydney, Australia.
authors.forename: Roger
authors.initials: R
authors.lastname: Bourne
mesh_terms: D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D011467:Prostate / Q000033:anatomy & histology*; D012815:Signal Processing, Computer-Assisted; D016707:Tissue Fixation
keywords: compartment models; diffusion; microstructure imaging; modeling; prostate; restricted diffusion