ABSTRACT
Traumatic brain injury (TBI) is a leading cause of death and lifelong disability throughout developed nations. TBI is the result of an external mechanical force applied to the skull leading to temporary and permanent impairments, functional disability, or psychosocial maladjustment. This chapter describes the advancements in noninvasive techniques that are able to detect trauma-induced structural and functional damage, great strides in understanding the pathophysiology of TBI have been made. Despite variable long-term outcomes across the range of severities based on the Glasgow Coma Scale classification, the majority of TBI cases, approximately 75%, are diagnosed as mild TBI. The primary injury to the brain is a result of sudden acceleration, deceleration, and/or rotational forces. The acceleration and deceleration of the brain can cause cortical contusions and hemorrhages when the brain hits the skull. In TBI, the secondary injury cascade ultimately results in necrotic or apoptotic cell death that contributes to measurable cerebral atrophy due to neuronal loss.
