Probing Microscopic Cellular Architecture in the Mouse Brain by Oscillating Gradient Diffusion Tensor Imaging

Manisha Aggarwal¹, Susumu Mori¹, Jiangyang Zhang¹

Diffusion measurements with conventional pulsed gradient diffusion MRI experiments reflect the combined effects of restriction barriers to water diffusion at multiple spatial scales, but cannot distinguish between different spatial scales. With oscillating diffusion gradients, it is possible to probe diffusion at separate spatial scales by varying the modulation frequency of the oscillating gradients. In this study, three dimensional diffusion tensor imaging (DTI) of perfusion-fixed mouse brains using oscillating diffusion-sensitizing gradients is presented. The resulting diffusion tensor spectrum D(f) revealed, for the first time, unique frequency-dependent tissue contrasts in the mouse cerebellum and hippocampus.