Normal and abnormal development of the cerebellum and brainstem as depicted by diffusion tensor imaging.

Diffusion tensor imaging (DTI) is an advanced MRI technique that measures the microscopic molecular motion of water to gain information about the brain structure. This modality and its application to fiber tractography have been increasingly used in the last years to study the neuroanatomical background of brain malformations. This article aims to give an overview of the application of DTI and fiber tractography on pediatric posterior fossa including malformations, acquired disorders affecting the white matter, and posterior fossa involvement in phacomatoses. For every disorder, we show the additional information that DTI and fiber tractography are providing compared to conventional MR sequences and discuss their significance. Additionally, we show at the beginning normal DTI and fiber tractography findings of the pediatric posterior fossa. Finally, we briefly discuss potential future uses for DTI and fiber tractography to further understand the pathogenesis of posterior fossa malformations and the neuronal plasticity and connectivity of acquired lesions affecting the posterior fossa.