Abstract #0274

Concha L, Gross D, Beaulieu C

Axonal degeneration of white matter is a key consequence of neuronalor axonal injury. Diffusion parameters were followed using diffusiontensor imaging (DTI) in three patients who underwent surgicalbisection of the corpus callosum. Diffusion anisotropy was reduced ina spatially dependent manner at one week and remained low 2-4 monthsafter the surgery. The lower FA was due to a reduction in paralleldiffusivity (consistent with axonal fragmentation) at 1 week, whereas an increase in perpendicular diffusivity (consistent with myelin degradation) was responsible at 2-4 months. DTI is capable of non-invasively following and staging Wallerian Degeneration in white matter.