There are two categories used nowadays to describe brain injury: The first is “mild traumatic brain injury,” and the second, simply, “traumatic brain injury.”
It is important to understand both terms because each have very specific meanings and are often misused. A mild traumatic brain injury is what we used to call a “concussion.” It means that there is disruption to the brain but not due to intrusion into the brain. In other words, a mild traumatic brain injury is not caused by something like a bullet entering the brain, bone or skull entering the brain, or blood pooling in the brain. This can be from bumping your head, or can be from your brain sort of sloshing within your skull, which is a terrible word to use but accurate, and that’s what the word mild refers to. It refers to the mechanism of injury to the brain. However, mild traumatic brain injury does not refer to the true severity of the injury. This is where the term is frequently abused, and insurance companies will often say, “Well, it was only mild traumatic brain injury, therefore, it could not have caused these symptoms,” which is entirely wrong. Mild traumatic brain injury can, in fact, cause devastating cognitive symptoms even though there has not been any physical intrusion into the brain matter such as a bullet.
In contrast, a “traumatic brain injury” is generally considered one where there is an injury to the brain which is caused by some sort of physical insult to the brain, specifically with objects like projectiles, pieces of bone, blood, other things that have intruded on the brain itself. Traumatic brain injuries are the ones that show up on CT scans and are sometimes seen even on X-rays.
Again, what we know about that is that there has been significant physical intrusion into the brain, and that it is traumatic in nature, but the source of the impact doesn’t tell us anything about the outcome of the brain injury. You can have a traumatic brain injury and recover 100%. On the other hand, you can have a mild traumatic brain injury and suffer long-term or continuing symptoms. So, these two terms are important to know because they distinguish the mechanism of injury, but they don’t tell us anything about the potential repercussions.
Can a concussion be as severe as a traumatic brain injury?
Absolutely. Mild traumatic brain injury can be as impairing as a traumatic brain injury. The real question is what happens to the brain; what interruption was there in the ability of the brain to respond from the insult? The answer can vary greatly. So, yes, you can have devastating symptoms from a mild traumatic brain injury.