Traumatic Brain Injury Among Veterans Returning From Afghanistan and Iraq

One of the most commonly encountered weapons in Operation Enduring Freedom and Operation Iraqi Freedom is the improvised explosive device (IED).1-3 From October 2001 until January 2005, explosive devices were responsible for nearly 80% of all casualties reported to the Joint Theater Trauma Registry.4 Compared with casualties in earlier conflicts, military casualties in Afghanistan and Iraq incur a greater percentage of injuries to the face, head, and neck.2 Improvements to personal protective equipment and vehicle armor have reduced death rates, but by improving survival, they may have increased the incidence of traumatic brain injury (TBI) among wartime casualties and perhaps also among veterans who appear physically uninjured. (We use the term “veteran” as an inclusive term for military personnel who served in a combat zone, regardless of the current status as a discharged veteran, active duty service member, or member of the military reserve or National Guard.) This article addresses the epidemiology, diagnosis, and treatment of mild TBI among combat veterans, with a particular focus on blast injury and the presence of comorbid posttraumatic stress disorder (PTSD). Causes of TBI Although current media and scientific attention is focused on TBI from wartime incidents, the causes of TBI among US military service members and veterans include combat, training accidents, and nonmilitary accidents. The incidents are typically associated with blunt head injuries in military service resulting from motor vehicle accidents, military aircraft accidents, accidents during field training exercises or hand-to-hand combat, and combat. Penetrating head trauma occurs but is far less frequent than either blunt injury or injury from blast exposure. Combat experience can lead to blast exposure, but certain military occupational specialists, such as explosive ordnance disposal or military bomb disposal experts, will experience repeated blast exposure in their daily work. Military operations in Afghanistan and Iraq are associated with exposure to the IED, typically a small weapon that contains 20 to 30 pounds of explosive, and the often larger vehicle-borne IED, a device with charge sizes up to several thousand pounds of explosive. There are 3 mechanisms by which an IED causes injury: blast, blunt impact, and fragment