Modelling uncertainty in two fibre-orientation estimates within a voxel
Cook P, Alexander D
University College London
The Probabilistic Index of Connectivity tractography method uses Monte-Carlo streamline generation to create maps of connection probability. A probability density function (PDF) is associated with the fibre orientation in each voxel. We present a new model of the fibre-orientation PDF that models the uncertainty of two distinct fibre orientations within a voxel. Unlike previous work, the new model does not assume circular contours of the PDF on the sphere. We show an example of the model where a Gaussian mixture model is used to estimate the two fibre orientations in a simulated fibre crossing.