In Vivo Detection of Axonal Plasticity in Rat Hippocampus Using DTI

Teemu Laitinen¹, Alejandra Sierra¹, Asla Pitknen¹, Olli Grhn¹

The ability of in vivo diffusion tensor imaging to detect axonal plasticity in dentate gyrus sub region of hippocampus was studied in rats after kainic acid induced status epilepticus. Our results show that fractional anisotropy of dorsal dentate gurys is increased 17 months after the brain injury when compared to healthy control animals. Histological evaluation showed significant increase in the density of mossy fiber sprouting and myelinated axons the kainic acid treated animals, consistent with the DTI results. The results of this study suggest that axonal plasticity can be detected using in vivo DTI.