Traumatic brain injury (TBI) affects approximately 3.5 million individuals annually in the United States and approximately 75% are the result of "mild" or concussive events. In the US military, it is estimated that roughly 20% of the deployed force suffered a head injury in the wars in Iraq and Afghanistan, 83.3% of whom endured a mild, uncomplicated TBI or concussion, the long-term impact of which is just beginning to be appreciated. Many of these Service members are young males, 20-30 years old who have decades of life to live with the complex and often debilitating impact of war-time brain injury. Although much effort has been placed on trying to better understand this type of injury, many of these studies have been forced to rely largely on self-reporting, retrospective medical records review or evaluations of only later stages of injury No study to date has prospectively followed active-duty US military from concussive brain injury to long-term outcome with advanced Magnetic Resonance Imaging (MRI) and clinical evaluation.
The overall goal of this study is to investigate advanced MR imaging and clinical outcome measures of concussive traumatic brain injury (TBI) in US military personnel injured during deployment. As part of previous collaborative efforts, we completed early prospective, longitudinal studies enrolling active-duty US military at 0-7 days, 0-30 days, and 0-90 days post-injury. All subjects met the DoD definition for mild uncomplicated traumatic brain injury . Non-brain injured control subjects were also enrolled at each time point for comparison. Early advanced MR imaging and clinical information was collected before these subjects were followed to 6-12 months. At 6- 12 months, advanced MR imaging was repeated and a battery of neurological, neuropsychological and psychiatric evaluations were completed. In total, 591subjects were enrolled through these efforts;54% TBI,46% control. This study will re-examine these subjects now 3-5 years post-injury and compare their current clinical and imaging presentation with the previously acquired longitudinal data.
Two groups of subjects will be studied: 1) subjects who sustained a concussive brain injury from blast during deployment, and 2) subjects without history of blast exposure and no diagnosis of brain injury from deployment. Group 2 serves as a control population for the blast-related concussive brain injury group.
We hypothesize that early clinical and imaging measures will correlate with 3 to 5 year late stage clinical outcome. This will offer predictive insight into the long-term impact of war-time concussive TBI thereby guiding new recommendations for clinical management and therapeutic intervention.