All About Traumatic Brain Injury

The term traumatic brain injury (TBI) refers to injuries to the brain that are caused by some form of traumatic impact. Traumatic brain injuries usually are caused by a blow to the head, violent shaking or penetration of the brain tissue. Depending on the cause and severity of the brain injury, brain damage can be mild, moderate or severe.

Initial symptoms of a traumatic brain injury may include:

  • Headache
  • Dizziness
  • Loss of consciousness
  • Blurred vision
  • Confusion
  • Memory loss
  • Seizures
  • Paralysis
  • Coma

In more serious cases of traumatic brain injury, complications can be fatal. While the severity of traumatic brain injuries varies, the long-term effects are often devastating and life-altering.

What is Traumatic Brain Injury?

Traumatic brain injury is sudden, non-congenital physical damage to the brain from an external force that temporarily or permanently disrupts normal brain function. Brain characteristics and functions that can be affected include consciousness, speech and language, memory, mobility, personality and others. Because the brain controls all bodily functions, any damage to the brain, regardless of severity, can impair physical and psychological activity.

Types of Traumatic Brain Injury

Types of traumatic brain injuries are divided into two categories: open head injury and closed head injury. Open head injuries are injuries in which the skull has been fractured or the membranes surrounding the brain (dura mater) have been breached. Open head injuries are very serious and often require surgery to extract pieces of the fractured skull and implant synthetic pieces. Closed head injuries, on the other hand, do not break the skull and are typically caused by blows to the head. Both open and closed head injuries can cause mild to severe brain damage.

Damage from traumatic brain injuries is classified as either focal or diffuse. Focal damage is confined to a small area of the brain where the head has been hit by an object or where an object has penetrated the brain. Diffuse damage is damage to several areas of the brain; it can be caused by lack of oxygen, aneurisms, infection, neurological diseases or violent collisions of the brain with the inside of the skull.

Traumatic Brain Injury Symptoms

Symptoms of traumatic brain injury vary depending on the severity of the injury. Mild traumatic brain injury victims may experience a brief loss of consciousness, temporary memory loss, headache, slurred speech or dilated pupils. Some mild traumatic brain injury victims do not lose consciousness at all. Moderate to severe brain injury victims may lose consciousness for an extended period of time (more than 30 minutes) and have long-term memory loss, seizures or convulsions, nausea or vomiting, limb paralysis, vision loss, hearing loss or bowel control loss. When a person sustains a blow to the head it is imperative that he or she receive immediate medical attention, regardless of the immediate symptoms of the injury.

Causes of Traumatic Brain Injury

Traumatic brain injuries are typically caused by blows to the head, collision between the brain and the inside of the skull, or both. Some of the most common causes of traumatic brain injury include falls, transportation accidents and assaults. Transportation accidents account for more than half of all traumatic brain injuries, including concussions, and are the leading cause of traumatic brain injury in people under 75 years old. Falls are the leading cause of traumatic brain injury in people over 75 years old. In addition, many traumatic brain injuries (about 20 percent) result from violent acts such as firearm assaults or child abuse. Sports-related accidents account for about 3 percent of all traumatic brain injury cases.

Traumatic Brain Injury Complications and Disabilities

Complications of traumatic brain injury vary depending on the cause and the extent of brain damage. Some of the most common traumatic brain injury complications include personality changes, insomnia, headache, cognitive disabilities and sensory changes. More severe traumatic brain injury complications include pooling of blood in the head (hematoma), epilepsy, amnesia, paralysis, coma and death. Additionally, studies have suggested a link between traumatic brain injury and the development of both Parkinson's disease and Alzheimer's disease.

Traumatic Brain Injury Diagnosis

Diagnosing traumatic brain injury often requires doctors to perform a physical examination of the head and a variety of verbal tests. Using either the Glasgow Coma Scale or the Rancho Los Amigos Coma Scale, they ask traumatic brain injury patients several questions to assess their level of consciousness and their ability to speak, move and open their eyes.

To further evaluate brain damage, doctors may order magnetic resonance imaging (MRI) scans, computed tomography (CT) scans or X-rays to identify any skull fractures, brain swelling or bleeding in the brain or skull (hematoma).

Traumatic Brain Injury Treatment

Treating traumatic brain injury occurs when a patient is admitted to the hospital. Doctors work diligently to stabilize his or her condition, which can include unblocking airways, maintaining blood flow to the brain and, in extreme cases, resuscitation. In addition, doctors treat open wounds and administer antibiotics to prevent infection. Once a patient has stabilized, his or her doctors may order MRI scans, CT scans, or X-rays to help assess the level of brain damage. Doctors may also prescribe anti-convulsion medication to prevent seizures.

In some instances, traumatic brain injury can lead to increased intracranial pressure. These cases often require surgery to accommodate brain swelling and excess fluid. Open head injuries may require surgery to remove broken skull fragments and insert synthetic pieces that protect delicate brain tissue.

Traumatic brain injury rehabilitation is an important part of treatment because it helps patients regain or manage impaired brain functions and minimizes long-term traumatic brain injury disabilities. Through rehabilitation, patients are sometimes able to regain important brain functions such as speech, memory and mobility. Rehabilitation can also help a victim's family cope with the tragedy.

Traumatic brain injury has many other causes, complications and treatments. Please read other articles on this site for more information on diagnosis, treatment and prevention of traumatic brain injury.

[Last revision: July 2013]

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