A severe blow to the head, such as the one that Michael Schumacher received recently in a skiing accident, can cause traumatic brain injury. It can either heal - or become life-threatening.
Even a small brain injury can have grave consequences. Although the bones that make up our skull protect the brain, strong concussions through a blow or a fall can damage the skull, the brain, and the blood vessels inside it, causing a so-called traumatic brain injury (TBI).
After an accident, it's not always easy to see whether and to what extent the brain has been injured. Dangerous hemorrhages or swellings often only occur hours or days later. For that reason, doctors often only judge the severity of an injury by its external symptoms - how the patient is behaving, whether or not they open their eyes when addressed, whether or not they are able to control their movements, whether they react to pain stimuli, and for how long they remain unconscious.
Traumatic brain injuries can be relatively harmless - or they can be deadly. Doctors subdivide the severity of brain injuries into various degrees: the first and mildest of these is commonly known as concussion. Scans show no damage, and if brain functions are impaired, they usually return to normal within around four days.
The second gradation occurs when the patient is unconscious for some time - 15 minutes or longer. A rule of thumb dictates that the longer unconsciousness continues, the greater the risk of lasting physical and mental damage. With this moderate form of brain injury, the injury generally fades after four weeks. After-effects, however - such as concentration problems, headaches, or dizzy spells - can continue for years.
Patients with a third-degree brain injury are often unconscious for more than an hour, and the neurological consequences are massive. A patient with a severe brain injury like this can suffer seizures, paralysis, and even personality changes. Such damage is usually irreparable.
A definitive diagnosis of the severity of a brain injury can be provided by imaging technology, such as computer axial tomography (CAT), which supplies three-dimensional x-ray scans of the brain. This allows doctors to see signs of hemorrhaging, bruises (or hematoma), and swellings (or edemata).
Patients with a moderate or severe traumatic brain injury should be treated in intensive care. An emergency operation is often necessary to reduce life-threatening pressure inside the skull, since the bone casing has no room for expansion.
In cases like this, the doctor has to drill small holes into the skull to relieve pressure from built-up blood or other fluids. Brain pressure needs be constantly monitored, while medication having a diuretic effect can also help reduce pressure.