Traumatic Brain Injury

A concussion is a minor brain injury that is caused by an impact to the head, shaking, or a sudden change in movement, like whiplash. Oftentimes, concussions cannot be seen through an imaging test, but they should still be considered serious and should be treated as so.

Concussions can cause headaches, problems with concentration, memory loss, and disorientation. Concussions are especially dangerous if more than one is sustained over time, or if a second one occurs before the first one heals (“second impact syndrome”).

Second Impact Syndrome: A second impact is more likely to cause severe brain damage than a first, even if the victim does not lose consciousness. If you suffer a blow to the head in the months following a brain injury, seek prompt medical care, even if you feel fine. Often, second concussions are a silent killer, since both impacts can appear minor at the time.

A brain contusion is a bruise of the brain tissue, just like one might have a bruise on their skin. And like any other bruise, they are caused by the breaking and leaking of small blood vessels. On the skin level, this leaking blood under the skin is what causes the blue coloring; on the brain, the leaking causes a plethora of issues that mostly relate to a building of pressure.

Brain contusions can be caused by any impact to the head. For example, a contusion may occur in a car accident when the head hits the steering wheel, a slip, and fall when the head hits the ground, or in a sports-related accident in which the brain takes a significant impact.

During the impact that causes a brain contusion, it’s possible for the brain to be damaged directly under the site of impact, on the opposite side from the point of impact as the brain is slammed into the opposing side of the skull, or both.

Contusions, like concussions, can range dramatically from minor to extremely severe. Severe contusions may cause a loss of consciousness, confusion, tiredness, emotional distress, or agitation. More severe contusions may cause the brain to swell, could prevent proper oxygenation, and other serious consequences.

Penetrating brain injuries occur when some type of object pierces through the skull. This may cause the object, or hair, skin, or fragments of the skull, to make contact with the brain. This contact with and force on the brain can cause serious injury to a concentrated, or large, part of the brain.

Penetrating brain injuries may be caused by any external force or object that is strong enough to break through the skull, such as:

• A slip-and-fall that causes the skull to crack
• A motor vehicle accident in which something penetrates or breaks the skull A gunshot wound to the head, which is the leading cause of death by TBI
• A sports-related injury due to excessive force

An anoxic brain injury occurs when the brain does not receive enough oxygen to operate properly. After just four to five minutes without a proper amount of oxygen, brain cells will begin to die and brain injury will occur. Since oxygen is carried to the brain by blood, anoxic brain damage most often occurs because of a blockage of this blood flow.

A diffuse axonal injury (DAI) is similar to a concussion in that it results from the brain moving, but it is often much more serious. With a DAI, the head so violently moves that the brain stem cannot keep up with the rate of movement, causing tears in the connections of the brain to the spinal cord. These tears can be microscopic, producing varying degrees of brain damage, or they can be quite large.

Tears that are sufficient may cause extremely serious, life-long effects or they can even be fatal. The severity of symptoms with this type of injury is largely dependent on the brain areas affected, the severity of the tears, and whether any other injuries — such as a contusion or concussion — were also sustained.

One type of traumatic brain injury is a hypoxic brain injury, which occurs when the brain receives some but not enough oxygen and suffers damage as a result. This is usually achieved by incomplete reduction of oxygen to the lungs or blood to the brain via some form of inefficient suffocation like:

• Near-drowning
• Near-hanging
• Cardiac arrest
• Carbon monoxide
• Exposure to poisonous gasses

One version of hypoxic brain injury is a hypoxic-ischemic brain injury, also called stagnant hypoxia or ischemic insult.