Multiple lines of evidence suggest that schizophrenia is associated with abnormalities in neural circuitry and impaired structural connectivity. Although largely investigated by imaging studies, very few results have been published on in-vivo image-based connectivity investigations, and those published report often contradictory findings. In this study, we propose to conduct a group study to evaluate the differences in structural connectivity between schizophrenic patients and control subjects using Diffusion MRI. The proposed methodology is based on Tractography, a technique inferring the main neural fiber tracks from Diffusion MRI data. We study mainly the thalamo-frontal fiber-tracts, supposed to be involved in schizophrenia.