Introduction to CNS Imaging, Trauma

Approach to Head Trauma

General Considerations

Epidemiology: Trauma is the most common worldwide cause

of death and disability in children and young adults. In these

patients, neurotrauma is responsible for the vast majority of

cases. In the USA and Canada, emergency departments (ED)

treat more than 8 million patients with head injuries annually,

representing 6-7% of all ED visits.

The vast majority of patients with head trauma are classified

as having minimal or minor injury. Minimal head injury is

defined as no neurologic alteration or loss of consciousness

(LOC). Minor head injury or concussion is epitomized by a

walking, talking patient with a Glasgow Coma Score (GCS) of

13-15, who has experienced LOC, amnesia, or disorientation.

Of all head-injured patients, ~ 10% sustain fatal brain injury,

whereas another 5-10% of neurotrauma survivors have

permanent serious neurologic deficits. A number have more

subtle deficits ("minimal brain trauma"), whereas 20-40% of

patients have moderate disability.

Etiology and Mechanisms of Injury

The etiology of traumatic brain injury (TBI) varies according to

patient age. Falls are the leading cause of TBI in children

younger than 4 years and in elderly patients older than 75

years. Gunshot wounds are most common in adolescent and

young adult male patients but relatively rare in other groups.

Motor vehicle and auto-pedestrian collisions occur at all ages