title: A simple and robust test object for the assessment of isotropic diffusion kurtosis.
abstract: OBJECTIVE
  To create a robust test object for the assessment of isotropic diffusion kurtosis and to investigate the relationships between barrier concentration and kurtosis and diffusion coefficients.
  
  
  METHODS
  Diffusion kurtosis imaging is an extension of conventional diffusion-weighted magnetic resonance imaging which provides a means of assessing the degree to which diffusion processes of spin-bearing particles are non-Gaussian, a property that is quantified by the kurtosis. We present a set of test objects, each possessing a different concentration of colloidal dispersion, allowing barrier concentration of the dispersed colloidal particles to be related to the kurtosis of the water diffusion. Diffusion coefficients from the kurtosis model and the monoexponential model are compared.
  
  
  RESULTS
  A relationship between barrier concentration and kurtosis is found, demonstrating that the diffusion process becomes less Gaussian as the barrier concentration is increased. Differences in the two estimates for the diffusion coefficients are examined. The test object is robust, displaying long-term reproducibility of results.
  
  
  CONCLUSIONS
  Colloidal dispersions provide a suitable and stable test object for the assessment and reproducibility measurements of kurtosis.
authors.affiliation: Institute of Life Science, College of Medicine, Swansea University, Singleton Park, Swansea, UK; Medical Engineering and Physics, King's College London, Faraday Building, 124-126, Denmark Hill, London, UK; Medical Physics, St. Thomas' Hospital, Westminster Bridge Road, London, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Phillips
authors.forename: Geoffrey D
authors.initials: GD
authors.lastname: Charles-Edwards
mesh_terms: D003102:Colloids; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007554:Isotopes; D016011:Normal Distribution; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D013113:Spin Labels
chemical_list: D003102:Colloids; D007554:Isotopes; D013113:Spin Labels
keywords: diffusion; kurtosis; magnetic resonance imaging