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.