Military-Relevant Traumatic Brain Injuries: A Pressing Research Challenge

296 long-term consequences, including those related to blast-induced traumatic brain injuries (TBIs), shows an increasing trend. The Defense and Veterans Brain Injury Center (DVBIC) estimated, on the basis of medical records and actual medical diagnoses, that more than 202,000 service members were diagnosed with TBI between 2001 and 2010, with the overwhelming distribution of mild TBI caused by blast. Nevertheless, it has been hypothesized that this number could be even higher given the fact that many war fighters with INTRODUCTION The DoD Personnel & Procurement Statistics data1 show that more than 73% of all U.S. military casualties in Operation Enduring Freedom and Operation Iraqi Freedom were caused by explosive weaponry (e.g., rocketpropelled grenades, improvised explosive devices, and land mines). The incidence of primary blast injury increased from 2003 to 2006, and returnto-duty rates in patients injured in explosions decreased by half.2 Although the mortality caused by explosion has remained low and unchanged, the incidence of last-induced neurotrauma, i.e., traumatic brain injuries caused by a complex environment generated by an explosion and diverse effects of the resulting blast, currently represents one of the highest research priorities in military medicine. Both clinical experience and experimental results suggest specific blast–body–brain interactions causing complex, interconnected physiological and molecular alterations that can lead to long-term neurological deficits. The Biomedicine Business Area at APL has developed a capability to reproduce all major types of military-relevant traumatic brain injuries (primary blastinduced, penetrating, and blunt head injures) comparable to those caused by explosions in theater by using well-defined experimental mouse models. The overarching research approach aims at obtaining a full understanding of blast-induced neurotrauma; developing reliable, fieldable, and user-friendly diagnostic methods; and designing novel treatments and preventive measures. Military-Relevant Traumatic Brain Injuries: A Pressing Research Challenge