Diffuse Axonal Brain Injury - Causes, Symptomatic Complications, Diagnosis, and Treatment

What Is Diffuse Axonal Brain Injury?

It is a type of traumatic brain injury caused by a rapid shifting of the brain inside the skull due to sudden jerky movements. It is one of the most common and devastating types of traumatic brain injury. It is also one of the major causes of unconsciousness and persistent vegetative state after severe head trauma. Diffuse axonal injury occurs in about half of all cases of severe head trauma, and it is the reason for primary damage in concussion cases. Unlike brain trauma, which occurs due to direct injury and deformation of the brain, diffuse axonal injury is a result of the traumatic shearing force that occurs when the head is rapidly accelerated or decelerated.

What Are the Causes of a Diffuse Axonal Injury?

Vehicle accidents are the most frequent cause of diffuse axonal injury. It can also occur as a result of child abuse, such as shaken baby syndrome. The major cause of damage in diffuse axonal injury is the disruption of axons, which are the long extensions of nerve cells through which they communicate with each other. With severe acceleration, deceleration, or rotation movements at the time of trauma, the nerve tissues tend to slide over each other, stretching the axons apart.

The damages are microscopic and mostly occur at the junction of white and gray matter inside the brain. When axons are harmed, the nerves will not be able to communicate with each other or function as a unit. This leaves the affected individual functionally disabled or in a state of coma. Hence, the swift backward and forward movement of the brain inside the skull is what triggers a diffuse axonal injury. This can occur due to the following:

• High-speed car accidents and motorcycle accidents.

• Falls, especially those that cause rapid whipping motion of the head.

• Violent physical attacks.

• Sporting injuries.

• Shaken baby syndrome, or child abuse.

What Are the Predicted Outcomes Following a Diffuse Axonal Injury?

The most frequent outcome of a diffuse axonal injury is a coma, and over ninety percent of patients with severe damage never regain consciousness. Those who do wake up afterward often remain significantly disabled. It can occur in every degree of severity, from very mild to moderate to very severe. A concussion may be a milder type of diffuse axonal injury. But a person suffering a diffuse axonal injury may have mental and physical limitations and may often depend on others to perform basic tasks. Based on severity, the injuries are grouped into three as:

1. Grade One - Mild diffuse axonal injury with microscopic changes in the brain.

2. Grade Two - Moderate diffuse axonal injury with gross lesions (involving corpus callosum).

3. Grade Three - Severe diffuse axonal injury (involving corpus callosum and brainstem).

What Are the Chief Symptoms of Diffuse Axonal Injury?

Loss of consciousness is the prevailing symptom in individuals with severe injury. In mild diffuse axonal injury, the patient may have a concussion disorder associated with other signs such as:

• Headache.

• Dizziness or loss of balance.

• Drowsiness or fatigue.

• Disorientation or confusion.

• Nausea and vomiting.

• Show trouble with sleeping or sleeping for longer than normal.

How Is a Diffuse Axonal Injury Diagnosed at the Hospital?

Like every other head injury event, individuals affected by diffuse axonal injury should be brought to the hospital for immediate care. Informing the doctor about the event of trauma helps assume the level of impact and severity of trauma. To assess the brain damage and functional status of the patient, one may conduct the following studies:

• Glasgow Coma Scale (GCS) Evaluation - A study to measure the severity of brain injury involving eye-opening, verbal response, and motor response (response to touch, pressure pain, and more). Where a score of thirteen to fifteen indicates mild injury, nine to twelve is moderate injury, and below eight shows severe traumatic brain injury.

• Imaging Studies - Because damage to the brain is microscopic, diagnosis of diffuse axonal injury with computed tomography (CT) scan may be difficult. However, a well-established magnetic resonance imaging (MRI) method called diffusor tensor imaging is used. This procedure provides a detailed view of the brain and more.

What Is the Treatment for a Diffuse Axonal Injury?

The affected individual should be put under a basic life support system if the trauma is severe. Reducing any swelling in the brain is the first course of action needed in the case of diffuse axonal injury. If this is delayed, it may cause further brain damage. Severe diffuse axonal injury has a likelihood of a vegetative state or death in the majority of cases. One may choose:

1. Surgery to stop bleeding inside the brain and remove large blood clots.

2. Steroids or anti-inflammatory drugs may help reduce swelling in some individuals.

3. Lab tests and spinal tapping may help identify signs of bleeding and chemical changes indicating nerve injury.

In mild to moderate cases, rehabilitation is possible. Depending on the individual, a recovery program may include the following:

1. Physical therapy.

2. Occupational therapy.

3. Speech therapy.

4. Recreational therapy.

5. Counseling.

6. Adaptive equipment training.

What Are the Initial Steps to Take With a Closed Head Brain Injury?

Immediate medical attention is the first priority. Seek medical help without delay. And till help arrives, do not try to move the injured individual, as this may aggravate the existing damages. When paramedics arrive, inform them about the details of the accidents and the possibility of sustaining a brain injury. Stabilizing the injuries in the best possible manner is the first step, followed by means of rehabilitation. The affected individual may need elaborate lifestyle modifications and support for their dear ones to recover to the maximum possible potential.

Conclusion:

Among the injuries reported from car accidents, falls, and assaults, a significant percentage of individuals belong to the diffuse axonal injury category. The reason is that such accidents always involve rotational forces or severe deceleration. Though a great number of affected individuals may not regain consciousness, those who wake up require rehabilitation. The traumatic brain recovery program involves a team of doctors, nurses, and specialists, including physical, speech, occupational and recreational therapists. Complete recovery may be possible in very mild cases.