Phillips Jonathan, Charles-Edwards Geoffrey D
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.
Magn Reson Med. 2015 May;73(5):1844-51. doi: 10.1002/mrm.25311. Epub 2014 Jun 10.
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.
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.
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.
Colloidal dispersions provide a suitable and stable test object for the assessment and reproducibility measurements of kurtosis.
创建一个用于评估各向同性扩散峰度的稳健测试对象，并研究屏障浓度与峰度及扩散系数之间的关系。
扩散峰度成像为传统扩散加权磁共振成像的扩展，其提供了一种评估含自旋粒子扩散过程偏离高斯分布程度的方法，该特性由峰度量化。我们展示了一组测试对象，每个对象具有不同浓度的胶体分散体，使得分散胶体颗粒的屏障浓度与水扩散的峰度相关。比较了峰度模型和单指数模型的扩散系数。
发现屏障浓度与峰度之间存在关系，表明随着屏障浓度增加，扩散过程偏离高斯分布的程度增大。研究了两种扩散系数估计值的差异。该测试对象很稳健，结果具有长期可重复性。
胶体分散体为峰度的评估和重复性测量提供了合适且稳定的测试对象。
