ABSTRACT
The most common type of traumatic brain injury (TBI) is a “closed TBI”, which occurs when the external force causes the brain to move within the skull. The mechanics of a TBI can be understood by knowing that the brain is similar in consistency to a firm jelly, and it is enclosed in a hard bony casing, the skull, with any space left filled with cerebrospinal fluid, which cushions the brain and provides buoyancy to protect it in everyday life. A TBI can also result in widespread damage, which affects a greater number of areas and is also known as diffuse axonal injury. An altered state of consciousness is the most consistent clinical characteristic following TBI. A second widely used clinical indicator of TBI severity is PTA duration. Duration of post-traumatic amnesia (PTA) predicts performance on a range of cognitive tests, and is related to functional outcome and post-injury vocational status.
