18F-AV-1451 PET Imaging in TBI

TBI Subjects Inclusion Criteria: TBI Subjects * Subjects that have consented and are currently enrolled in either Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI), Evaluation, Pathogenesis, and Outcome of Subjects with or Suspected Traumatic Brain Injury Protocol Number: CNS: 10-N-N122, or Evaluation and Diagnosis of Potential Research Subjects with Traumatic Brain Injury (TBI): Protocol Number: 11-N-0084 * History of having sustained a TBI \< 6 weeks prior to enrollment * Can tolerate PET and MRI scan procedures Control Subjects * MMSE ≥ 28 * No significant history of cognitive impairment * No prior history of TBI * Can tolerate PET and MRI scan procedures Exclusion Criteria: * Have behavior dysfunction that is likely to interfere with imaging * Are claustrophobic or otherwise unable to tolerate the imaging procedure * Have current clinically significant cardiovascular disease, or clinically significant abnormalities on screening ECG * A history of additional risk factors for Torsades de Pointes (TdP) or are taking drugs that are known to cause QT-prolongation * Have a current clinically significant infectious disease, endocrine or metabolic disease, pulmonary, renal or hepatic impairment, or cancer * Are females of childbearing potential who are not surgically sterile, not refraining from sexual activity or not using reliable methods of contraception * Have had a non-study related radiopharmaceutical imaging or treatment procedure within 7 days prior to the 18F-AV-1451 imaging session * Have current alcohol dependence or alcohol dependence within the past 1 year * Are currently participating in another interventional clinical trial * Have evidence of a penetrating brain injury * Have participated in contact sports in college or after high school age