HealthDay News — Even mild traumatic brain injury may cause brain damage and affect thinking and memory, according to researchers.
Iain D. Croall, from Newcastle University in the United Kingdom, and colleagues scanned 53 patients, an average of six days post-injury. One year later, 23 patients were rescanned. Thirty-three matched control subjects were also assessed. Cognitive testing was completed at the time of scanning.
Increased axial diffusivity drove a fractional anisotropy (FA) increase acutely, while decreased radial diffusivity drove a negative regression between FA and Verbal Letter Fluency across widespread white matter regions, the researchers reported in Neurology. This was particularly seen in the ascending fibers of the corpus callosum.
Astrogliosis and compaction of axonal neurofilament are thought to cause raised FA, which would also affect cognitive functioning. FA was decreased chronically, suggesting myelin sheath disintegration, but remained negatively regressed with Verbal Letter Fluency in the anterior forceps.
“Acute mild/moderate traumatic brain injury is characterized by increased tissue FA, which represents a clear neurobiological link between cognitive dysfunction and white matter injury after mild/moderate injury,” the researchers wrote.