Improving the Fit of the Diffusion Kurtosis Tensor by Emphasizing the Directions of Restricted Water Motion

Tristan Anselm Kuder¹, Bram Stieltjes, Amir Moussavi¹, Frederik Bernd Laun¹

The Diffusion Kurtosis Tensor (DKT) describes the directional dependence of the kurtosis which quantifies non-Gaussian diffusion. The aim of this study was to evaluate the quality of the tensor determination under well-defined conditions using diffusion phantoms. The DKT was determined using two methods. While the standard method using a pseudoinverse matrix fails, the new method emphasizing the high kurtosis values allows a reliable fit of the DKT. Comparison of the measurement using 30 directions to that with 256 directions shows the high quality of the tensor model when combined with the improved calculation method.