Three-dimensional diffusion tensor microimaging for anatomical characterization of the mouse brain

Diffusion tensor imaging is gaining increasing importance for anatomical imaging of the developing mouse brain. However, the application of diffusion tensor imaging to mouse brain imaging at microscopic levels is hindered by the limitation on achievable spatial resolution. In this study, fast diffusion tensor microimaging of the mouse brain, based on a diffusionweighted gradient and spin echo technique with twin-navigator echo phase correction, is presented. Compared to echo planar and spin echo acquisition, the diffusion-weighted gradient and spin echo acquisition resulted in significant reduction in scan time and had minimal image distortion, thereby allowing acquisition at higher spatial resolution. In this study, three-dimensional diffusion tensor microimaging of the mouse brains at spatial resolutions of 50-60 μm revealed unprecedented anatomical details. Thin fiber bundles in the adult striatum and white matter tracts in the embryonic day 12 mouse brains were visualized for the first time. The study demonstrated that data acquired using the diffusion tensor microimaging technique allow three-dimensional mapping of gene expression data and can serve as a platform to study gene expression patterns in the context of neuroanatomy in the developing mouse brain.