In vivo diffusion spectrum imaging of non-human primate brain: initial experience in transcallosal fiber examination.

In comparison with conventional diffusion tensor imaging (DTI) technique, diffusion spectrum imaging (DSI) allows for delineating crossing and touching fibers in the brain and has been explored in clinical and preclinical studies. Non-human primates (NHPs) resemble most aspects of human and are widely employed in various neuroscience researches and pharmaceutical development. In the present study, a parallel imaging-based DSI protocol was implemented for in vivo fiber tracking of macaque monkey brains on a 3.0 T clinical scanner. Transcallosal fiber tracts of adult macaque brains were examined with DSI and compared with those from a a conventional DTI protocol. The results demonstrate that DSI can reveal the transcallosal fiber bundles much more extensively than the conventional DTI. The preliminary results suggest that DSI may provide a feasible and robust approach for characterizing the fiber pathways in various disease models of NHPs.