Brain Damage Seen Even With Mild Head Injury
(HealthDay News) — Even mild traumatic brain injury may cause brain damage and affect thinking and memory, according to a study published online July 16 in Neurology.
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.
The researchers found that 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. 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 regressed negatively 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 authors write.