Longitudinal Changes of Diffusion Tensor Imaging in Acute Stages of Post-Mortem Animal Brain Tissue Decomposition

Luis Concha¹, Oscar Mndez², Fernando Barrios-Alvarez¹

DTI is often used in post-mortem animal studies. Although it is recognized that tissue processing may alter diffusion characteristics, it is unclear how the normal decomposition of the brain tissue modifies DTI parameters. We performed brain DTI on a 3T scanner on three adult rabbits before death and following euthanasia for a period of 12-14 hours. Fractional anisotropy changed very little over the time studied, while mean diffusivity declined progressively over time, to an extent that cannot be explained by temperature changes alone, but rather by tissue degeneration such as vacuolization and cell autolysis.