title: MRI quantification of non-Gaussian water diffusion by kurtosis analysis.
abstract: Quantification of non-Gaussianity for water diffusion in brain by means of diffusional kurtosis imaging (DKI) is reviewed. Diffusional non-Gaussianity is a consequence of tissue structure that creates diffusion barriers and compartments. The degree of non-Gaussianity is conveniently quantified by the diffusional kurtosis and derivative metrics, such as the mean, axial, and radial kurtoses. DKI is a diffusion-weighted MRI technique that allows the diffusional kurtosis to be estimated with clinical scanners using standard diffusion-weighted pulse sequences and relatively modest acquisition times. DKI is an extension of the widely used diffusion tensor imaging method, but requires the use of at least 3 b-values and 15 diffusion directions. This review discusses the underlying theory of DKI as well as practical considerations related to data acquisition and post-processing. It is argued that the diffusional kurtosis is sensitive to diffusional heterogeneity and suggested that DKI may be useful for investigating ischemic stroke and neuropathologies, such as Alzheimer's disease and schizophrenia.
authors.affiliation: Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York 10016-3295, USA. jj33@nyu.edu
authors.forename: Jens H
authors.initials: JH
authors.lastname: Jensen
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Helpern
mesh_terms: D004058:Diffusion; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008962:Models, Theoretical; D014867:Water / Q000378:metabolism*
chemical_list: D014867:Water