ABSTRACT
It has been questioned whether traumatic brain injury forms a model of acquired psychiatric illness.1 Neurosurgical care in the U.S. has markedly progressed in the last 25 years. The good news from this progress is that the survival rate of traumatically brain-injured persons has increased dramatically. The bad news is that improved survival rates have led to a dramatic increase in the number of cognitively and behaviorally impaired persons with long-term neuropsychiatric disorders as a consequence of traumatic brain injury. Roughly 2 million cases of head trauma occur in the U.S. each year.2 Traumatic brain injury results principally from vehicular accidents, falls, acts of violence, and sports injuries and is twice as likely to occur in men than women. The estimated incidence is 100 per 100,000 persons, with 52,000 annual deaths. The highest incidence is among persons aged 15 to 24 years and those older than 75 years, with a less striking peak at age 5 years. Prevalence is 2.5 to 6.5 million persons.11 Of these injuries, almost 25% require hospitalization and 80,000 to 90,000 persons are left with some level of chronic disability.
