Computing White Matter Fiber Orientations in High Angular Resolution Diffusion-Weighted MRI

Diffusion tensor magnetic resonance imaging (DTI) can resolve white matter fiber orientations within voxels in which the diffusion is characterized by Gaussian diffusion process. High angular resolution diffusion imaging (HARDI) adds the capability of describing the apparent diffusion coefficient (ADC) profile of voxels that contain kissing, branching and crossing fiber configurations. We present a new method for recovering BiGaussian model from HARDI. This method divides the parameters of biGaussian model into the parameters describing the shape of ADC profile and the parameters defining the orientation of ADC profile. The two types of parameters are recovered in separate steps.