Traumatic Brain Injuries: Diagnosis and Severity Classifications

Diagnosis and Severity Classifications

The usual mechanism of injury causing a traumatic brain injury involves an impact to the head, a rapid movement or displacement of the brain within the skull, or both. Significant sudden acceleration/deceleration forces sustained in some high-impact car accidents can cause not only a whiplash neck injury but also brain trauma. The trauma nature usually is referred to either as being open head (some degree of skull penetration) or closed head (no actual skull penetration).

Traumatic brain injuries are classified by assessment systems either as being mild, moderate or severe. [See: Diagnostic Criteria for Major or Mild Neurocognitive Disorder Due to Traumatic Brain Injury, DSM-5™ (2013), published by the American Psychiatric Association, as well as the Glasgow Coma Scale and Ranchos Los Amigos Scale.] Such diagnostic criteria typically consider key factors such as: relative loss of consciousness periods; presence of posttraumatic amnesia; disorientation or confusion at initial assessment; neurological deficits; and trauma evidence on brain imaging. Clinically speaking, at least one of the foregoing or similar findings must be present in order for a traumatic brain injury diagnosis to be made.

The well-known term concussion, which refers to some impact to the head which affects normal brain function, if even subtly, is encompassed by the term mild traumatic brain injury (MTBI). In fact, the medical community has suggested that use of the latter term would potentially foster a better appreciation of the real concerns that a concussion poses, especially when such occurs multiple times over a person’s life.   This movement has been bolstered by recent medical studies that have documented the existence of what is referred to as chronic traumatic encephalopathy (CTE), a degenerative brain disease believed caused by repetitive head trauma (concussions), especially those sustained by athletes in contact sports.

Ultimately, traumatic brain injuries may cause significant neurological and neurophysiological impairments and disabilities, including paralysis and seizure disorders, as well as deficits involving cognitive (i.e., related to awareness, perception, reasoning, judgment and memory), behavioral and emotional functions. Medical specialists typically refer to these last three areas more precisely as neurocognitive, neurobehavioral, and psychiatric/psychological symptoms and conditions.

Next: Traumatic Brain Injuries: Patient Outcomes