Traumatic Brain Injury

Excerpt

Traumatic Brain Injury (TBI) can be caused by any external mechanical forces, impact, rapid acceleration-deceleration, or penetrating injury to the head and presents a significant health challenge worldwide. This article primarily addresses those suffering from a traumatic brain injury or closed head injury, which is the most common form of TBI, rather than a penetrating head injury. The various types of closed head injuries include conditions like concussion, parenchymal contusions, and various types of intracranial hematomas. In the United States, TBI affects approximately 1.7 million individuals annually, with a noticeable prevalence among older adolescents (ages 15 to 19 years old) and adults over the age of 65. These injuries frequently impact the frontal and temporal brain regions, leading to substantial healthcare burdens, particularly in lower-income countries.

TBI severity is classified into three categories: mild, moderate, and severe. Mild TBI or concussion is clinically defined as a loss of consciousness lasting <30 minutes, post-traumatic amnesia lasting <24 hrs, or any alteration of consciousness. Moderate or severe TBI is clinically defined as a loss of consciousness lasting ≥ 30 minutes to prolonged coma, post-traumatic amnesia lasting ≥24 hours up to permanently, or a Glasgow Coma score as low as 3.

A Glasgow Coma Scale (GCS) score is also used in the description of those with TBI. It is scored out of 15, where it is defined as mild when the GCS is 14-15, moderate when the GCS is 9-12, and severe when the GCS is 3-8. A mild TBI (otherwise known as a concussion) comprises over 90% of the cases. Symptoms vary widely, from transient consciousness to prolonged unconsciousness or coma in severe cases. Long-term risks include persistent postconcussive symptoms, such as headaches, dizziness, difficulty concentrating, and depression. Recurrent TBIs can lead to cumulative, permanent neurologic damage and chronic traumatic encephalopathy (CTE), emphasizing the critical need for research and education to understand the long-term effects of TBI.