Brain injuries are classified into two main types-Acquired and Traumatic. In either case the brain does not function properly, which may be temporary or last lifelong. The following HealthHearty article discusses types and levels of brain injury.
A birth trauma can also result in brain injury, and is referred to as congenital brain damage.
Every year, over 1.7 million people in the United States sustain some form of brain injury. Quite a few cases of brain injury go unreported, as the damage incurred does not last long. A mild brain trauma usually does not require medical intervention. However, a severe brain injury that causes significant impairment has been a cause for concern, and accounts for substantial injury-related deaths in the US.
A head trauma is one of the most common causes of brain injury. A head injury, due to a physical assault on the head, can alter normal brain function. However, all cases of brain damage do not necessarily occur from head trauma. Diseases, particularly neurological illnesses, are also responsible for causing damage to the brain.
Acquired Brain Injury (ABI)
Acquired brain injury, arising from internal occurrences, is classified as non-traumatic brain injury. The internal damage to the brain in ABI has been attributed to stroke, infections (encephalitis, meningitis), or formation of tumors. ABI can also result from hypoxia (restricted oxygen supply to the brain), anoxia (complete loss of oxygen flow to the brain), excessive alcohol consumption, drug abuse, and exposure to toxic chemicals.
Traumatic Brain Injury (TBI)
Brain-related injuries resulting from external force come under this category. It is an external impact that hits the head hard enough to damage the brain. A slip and fall, a knock with a blunt object, and automobile accidents can cause brain injuries. To put it simply, a violent blow to the head is responsible for causing traumatic brain injuries.
Types of TBI
In this type of injury, the brain function disrupts temporarily. Concussions may cause unconsciousness that is often short-lived, and is followed by headache, ringing in ears, dizziness, nausea, and tiredness. People playing sports like soccer, football, and rugby, commonly suffer from concussions that are considered to be the least-severe form of brain injury.
When the head is struck by an object, it may cause a contusion, that is marked by formation of bruise in the brain tissue. Contusions typically cause structural brain damage, in which blood leaks from broken blood vessels. This results in hematoma-pooling of blood around the brain tissue. The specific part of the brain that bleeds appears swollen. Contusions, considered to be more severe than concussions, reduce oxygen flow to the brain.
In this type of injury, the damage does not remain restricted at the site of impact. The injury also occurs at the opposite side of the area of the brain that was affected in the injury. Thus, contusion develops not only at the impacted site, but also in the region opposite to the site of injury. This happens because the head blow is so severe that the brain shifts and hits the opposite side of the skull, causing another contusion to form within the brain.
Diffuse Axonal Injury (DAI)
In this type of brain injury, the damage does not remain confined to a particular area, but affects a major part of the brain. DAI occurring from high speed vehicle accidents, causes the brain to shake violently and rapidly within the bony skull, resulting in widespread damage to the nerve tissue of the brain. No wonder, most cases of diffuse axonal injury result in coma, with majority of patients failing to recover from this state of unresponsiveness. Those who regain consciousness tend to suffer from lifelong cognitive impairments. Also referred to as a closed head injury, DAI that causes extensive damage, is marked by multiple hemorrhages in the brain tissue. Although death from DAI is a rarity, in over 90% of cases, the patient appears in a continuous vegetative state.
The shaken baby syndrome is a type of DAI that occurs when an infant under 2 years of age is shaken too fast and repeatedly. This violent shaking of the head causes the brain to move back and forth within the skull. So, when the brain repeatedly strikes against the skull, it is likely to get severely damaged, eventually leading to diffuse axonal injury. Parents, in an attempt to control tantrums of their child, may give such punishment, which may cause permanent brain damage.
The impact of the external force is so strong that the object pierces through the skull and reaches the brain. This is the most severe form of brain injury that often results from gunshots or when assaulted with a sharp weapon, such as a knife. A penetrating injury can also be a through-and-through injury, in which the object is fast enough to perforate and exit the head.
Mild Brain Injury
In this type of brain injury, the person becomes unconscious only for a short amount of time. He regains consciousness within a few minutes, and this is followed by dizziness and confusion.
Moderate Brain Injury
The person remains in an unconscious state for quite some time, that may vary from several minutes to several hours. Confusion may prevail for days, and in some cases, extend for weeks or even months. Apart from confusion, the person may face difficulty in mobility, and suffer from cognitive dysfunction and behavioral problems that may last for months.
Severe Brain Injury
Unconsciousness associated with severe brain injury continues for weeks or months. The victim goes into coma or a vegetative state. The brain injury inflicts irreparable damage, resulting in lifelong impairment.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.