Brain Wars: The Battle To Track And Diagnose Brain Injuries Traumatic brain injury, TBI, is often called the "signature injury" of the current conflicts in Afghanistan and Iraq. TBI is most often caused by powerful blasts from improvised explosive devices, the insurgents' weapon of choice. Although military officials and health professionals have debated the proper diagnosis and treatment of TBI for a decade, there is still no consensus. Many veterans must fight for treatment for their injuries once they return home.