Background: Diffuse axonal injury (DAI) causes neurodegenerative processes in brain which can last weeks and months after traumatic brain injury. Aim of this study was to assess structural changes of corpus callosum and corticospinal tracts in dynamics using diffusion-tensor magnetic resonance imaging (DT-MRI) in severe DAI.
Materials and methods: 14 patients with severe DAI (GCS < or = 8 in acute period) were examined using DT-MRI. In 12 cases 1.5 Tesla device was used, in 2-3 Tesla tomography was applied. Initial studies were performed on 3rd-17th days after injury and control studies were done between 3 weeks and 33 months after injury. Outcomes were assessed using GOS 6 months after injury and later.
Results: MR-tractography demonstrated almost absolutely absent visualization of ascending fibers of corpus callosum 3-20 weeks after brain injury in 5 patients with poor outcomes (severe disability and persistent vegetative state). Raized asymmetry of corticospinal tracts was associated with hemiparesis or quadriparesis in the same patients. In 6 patients with severe disability partial loss and thinning of corpus callosum fibers were observed. In 2 patients with good recovery and moderate disability repeated studies showed no severe changes in structure of corpus callosum.
Conclusion: DT-MRI presents new data about structural changes of white matter tracts in traumatic brain injury.