Remote neurodegeneration in a rat contusion spinal cord injury model: a combined MRI and histological study

MRI has been widely used to investigate the structural damage after traumatic spinal cord injury (SCI). While most small animal studies have focused on the injury site, remote SCI-related damage along the neuraxis has received less attention. Here, we demonstrate that ex vivo diffusion MRI and cross-sectional area measurements are sensitive to remote neurodegeneration in a rat contusion SCI model, showing gray matter and dorsal column atrophy alongside decreased fractional anisotropy in the dorsal columns several spinal levels rostral to the injury epicenter. Imaging findings were consistent with SMI32 immunohistochemistry with axonal degeneration mostly concentrated in the dorsal column.