Traumatic axonal injury despite clinical phenotype of mild traumatic brain injury: a case report.

Objectives: We report on a patient who suffered traumatic axonal injury (TAI) of various neural tracts despite airbag deployment following mild traumatic brain injury (TBI), which was demonstrated by diffusion tensor tractography (DTT).
Case Description: A 58-year-old female patient suffered from head trauma resulting from an in-car traffic accident. At the time of head trauma, her head and face hit the deployed airbag after flexion-hyperextension-rotation injury. The patient's Glasgow Coma Scale score was 15. Since the day of head trauma, she began to feel headache and upper back pain at the mid-thoracic area. At 7 days after onset, she began to feel pain on the left hand, which spread to the right hand and leg: throbbing and cold pain without allodynia or hyperalgesia (visual analogue scale score: 5). She also felt mild weakness of all four extremities and mild memory impairment. On 4-week DTT, the corticospinal tract showed partial tearing at the subcortical white matter level in both hemispheres . The right fornical crus and right anterior cingulum were discontinued, and narrowing and partial tearing were observed in both spinothalamic tracts.
Conclusions: TAI of four kinds of neural tracts was demonstrated in a patient with mild TBI despite airbag deployment, using DTT.