Know the types of traumatic brain injury

Traumatic brain injuries vary dramatically in severity and potential outcomes. In fact, the term TBI refers to diverse injuries that affect the head, skull and brain.

Review the common types of TBI so you can seek appropriate help in this situation.

Primary injuries

Injuries that occur at the time of the initial impact or penetration are the primary injuries. These may include:

  • Diffuse axonal injury, a type of trauma that severs nervous cell connections
  • Contusion, or bruising of brain tissue
  • Skull fractures, sometimes causing leakage of cerebral spinal fluid
  • Intracranial hematomas, such as bleeding or blood clot development within the brain, skull and nearby structures

The doctor may further categorize a primary injury as closed or penetrating. A closed injury does not impact the dura, the outer layer of the protective covering surrounding the brain within the skull. A penetrating TBI does involve this layer, typically resulting in more serious injury.

Secondary injuries

These injuries result from the physical and metabolic impact of the primary injuries. Common secondary injuries include:

  • Hydrocephalus, the buildup of fluid in the brain
  • Cerebral edema, which causes increased pressure within the skull
  • Ischemia, a condition that can result in stroke because of limited oxygen to the brain
  • Low blood pressure (hypotension)
  • Limited oxygen to the organs and tissues (hypoxia)

If you suffer a TBI, the doctor will also categorize your injury as mild, moderate or severe. A concussion is an example of a common mild TBI. Low-velocity injuries such as a sports tackle or a short fall may result in minor TBI, while high-velocity injuries such as auto accidents tend to cause more severe symptoms.