Part of Advances in Neural Information Processing Systems 18 (NIPS 2005)
Ofer Pasternak, Nathan Intrator, Nir Sochen, Yaniv Assaf
Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) is a non inva- sive method for brain neuronal fibers delineation. Here we show a mod- ification for DT-MRI that allows delineation of neuronal fibers which are infiltrated by edema. We use the Muliple Tensor Variational (MTV) framework which replaces the diffusion model of DT-MRI with a mul- tiple component model and fits it to the signal attenuation with a vari- ational regularization mechanism. In order to reduce free water con- tamination we estimate the free water compartment volume fraction in each voxel, remove it, and then calculate the anisotropy of the remaining compartment. The variational framework was applied on data collected with conventional clinical parameters, containing only six diffusion di- rections. By using the variational framework we were able to overcome the highly ill posed fitting. The results show that we were able to find fibers that were not found by DT-MRI.