Traumatic Brain Injury (TBI) Causes and Complications

A traumatic brain injury (TBI) is an injury that causes harm to the brain. Falling, car accidents, sports injuries, and physical attacks can all cause a TBI.

Some TBIs are mild, causing headaches or dizziness that resolve within days. Other TBIs cause serious, long-term complications like paralysis, tremors, or personality changes.

TBIs are diagnosed with a physical exam, brain imaging, and concussion testing. The treatment varies by the location and severity of the injury but may involve medications, rehabilitation, or surgery.

This article describes the symptoms and causes of a traumatic brain injury, including what is involved in the diagnosis and treatment of TBIs.

What Are the Symptoms of a Traumatic Brain Injury?

A variety of symptoms can occur with a TBI. You might notice symptoms immediately after the trauma or several weeks or months later. There may also be physical signs, like a bump on the head or bleeding, or no external symptoms at all.

The effects of a minor TBI can sometimes resolve within a few hours. Severe TBIs may cause prolonged effects lasting for weeks, months, or even a lifetime.

Symptoms of a TBI may include:

• Headaches
• Neck pain
• Dizziness or vertigo (spinning sensations)
• Loss of balance
• Nausea or vomiting
• Photophobia (light sensitivity)
• Tinnitus (ringing in the ears)
• Vision changes
• Loss of sense of smell
• Drowsiness
• Agitation
• Confusion
• Personality changes
• Memory problems
• Myoclonus (twitches) or tremors
• One-sided body weakness
• Loss of coordination
• Trouble walking
• Loss of consciousness
• Seizures or convulsions
• Paralysis
  

What Are Common Causes of a Traumatic Brain Injury?

The brain is usually well protected by the skull, three layers of tissues called meninges, and the scalp. A powerful impact or a sudden, rapid movement can disrupt nerves, parenchyma (functional tissues), and blood vessels servicing the brain.

These injuries can be broadly classified as:

• Concussive (impact) injuries: This is when the head is hit directly, causing shockwaves to the brain traveling in all directions simultaneously. This can cause brain swelling (edema) and a symptom called a concussion.
• Acceleration-deceleration injuries: This is when your head is moving at a high speed and stops abruptly, causing the brain to slam against the side of the skull. Brain edema and intracranial bleeding are common with these injuries.
• Penetrating injuries: This is when the scalp and skull are breached by a violent blow to the head and the brain is directly injured.

Examples of these injuries include:

• Sudden head jerking, such as in a car accidents
• Falling and hitting your head on a hard surface
• Head impacts from sports like soccer, football, and lacrosse
• Direct blows to the head from sports like boxing
• Physical attacks to the heads
• Repetitive head jerking, as in shaken baby syndrome
• A penetrating would be like a gunshot

TBI does not necessarily involve a skull fracture or skin wound. Closed traumatic brain injuries (also called closed head injuries or CHI) occur when the force of a blow to the head causes a brain injury without notable harm to the brain or scalp.

How Traumatic Brain Injury Is Diagnosed

If you have had a TBI, the healthcare provider will assess the extent and severity of the injury by first taking a detailed medical history and performing a physical exam. The physical exam will include an assessment of your hearing and hearing (including a check of pupil dilation).

A neuropsychological test may also be used to evaluate mental functions like reading, memory, language, attention, learning, processing speed, reasoning, and problem-solving as well as mood and behavior

An assessment tool called concussion testing will commonly be performed to look for "red flags" of a severe brain injury based on the following hallmark signs:

• Severe confusion
• Sustained vomiting
• Prolonged memory loss
• Extended loss of consciousness
• Severe drowsiness
• Worsening or continuous headache
• Trouble walking or talking
• Weakness or numbness on one side of the body
• Seizures or convulsions

If any "red flags" are noted, brain imaging may be ordered to check for problems like subdural hematoma, intracerebral hemorrhage (a "brain bleed"), or epidural hematoma (a pocket of blood between the skull and meninges). Options include:

• Computed tomography (CT), which creates a three-dimensional X-ray of the brain
• Magnetic resonance imaging (MRI), which creates highly detailed images of soft tissues

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How Traumatic Brain Injuries Are Treated

The treatment of TBI depends on the severity and type of brain injury you sustain. You may need a combination of treatments, including medications, surgery, and rehabilitation. Recovery may take days, weeks, or months, or require ongoing care.

Medications

Medical management may be needed to reduce edema and control severe symptoms like head pain and seizures. This may involve intravenous (IV) fluids, corticosteroid (steroid) drugs, anticonvulsants, and other medications.

Surgery

If you have a large bleed in your brain, you will need to have it evacuated (released). This often requires emergency surgery in which a portion of the skull is temporarily removed to ease intracranial pressure.

In some situations, this can be done through a burr hole, which is a small hole drilled into the skull.

Rehabilitation and Recovery

A brain injury may result in the loss of some physical or cognitive (thinking) abilities. Rehabilitation strategies may include physical therapy, occupational therapy, speech therapy, cognitive therapy, and counseling.

Summary

A traumatic brain injury (TBI) is any injury that damages the brain either temporarily or permanently. Symptoms can range from headaches, nausea, and drowsiness to seizures, loss of consciousness, and paralysis.

A TBI may be due to a concussive, acceleration/deceleration, or penetrating injury. The diagnosis may involve a physical exam, neuropsychological testing, concussion testing, and imagining studies. The treatment can vary but may include medications, rehabilitation, or surgery.