title: Microstructure Imaging of Crossing (MIX) White Matter Fibers from diffusion MRI.
abstract: Diffusion MRI (dMRI) reveals microstructural features of the brain white matter by quantifying the anisotropic diffusion of water molecules within axonal bundles. Yet, identifying features such as axonal orientation dispersion, density, diameter, etc., in complex white matter fiber configurations (e.g. crossings) has proved challenging. Besides optimized data acquisition and advanced biophysical models, computational procedures to fit such models to the data are critical. However, these procedures have been largely overlooked by the dMRI microstructure community and new, more versatile, approaches are needed to solve complex biophysical model fitting problems. Existing methods are limited to models assuming single fiber orientation, relevant to limited brain areas like the corpus callosum, or multiple orientations but without the ability to extract detailed microstructural features. Here, we introduce a new and versatile optimization technique (MIX), which enables microstructure imaging of crossing white matter fibers. We provide a MATLAB implementation of MIX, and demonstrate its applicability to general microstructure models in fiber crossings using synthetic as well as ex-vivo and in-vivo brain data.
authors.affiliation: Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Hamza
authors.initials: H
authors.lastname: Farooq
authors.affiliation: Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
authors.forename: Junqian
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Jung Who
authors.initials: JW
authors.lastname: Nam
authors.affiliation: Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Keefe
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Essa
authors.initials: E
authors.lastname: Yacoub
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA, USA.
authors.forename: Tryphon
authors.initials: T
authors.lastname: Georgiou
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Christophe
authors.initials: C
authors.lastname: Lenglet
mesh_terms: D001369:Axons; D003337:Corpus Callosum / Q000000981:diagnostic imaging*; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D008959:Models, Neurological; D066127:White Matter / Q000000981:diagnostic imaging*