Longitudinal changes in gray and white matter microstructure during epileptogenesis in pilocarpine-induced epileptic rats

Diffusion-weighted magnetic resonance imaging (MRI) has provided a noninvasive insight into the microstructural characteristics of tissue and anatomical connectivity without exogenous contrast agents. In particular, the tensor model [1] has been extensively used in the field of epilepsy for assessing hippocampal cell death, gliosis, and even axonal plasticity in humans [2,3] and experimental animals [4–8]. One of the most commonly derived diffusion tensor imaging (DTI) measures is fractional anisotropy (FA), which may be interpreted as a marker to identify subtly disturbed white matter microstructure.