title: Abnormal White Matter Blood-Oxygen-Level-Dependent Signals in Chronic Mild Traumatic Brain Injury.
abstract: Concussion, or mild traumatic brain injury (mTBI), can cause persistent behavioral symptoms and cognitive impairment, but it is unclear if this condition is associated with detectable structural or functional brain changes. At two sites, chronic mTBI human subjects with persistent post-concussive symptoms (three months to five years after injury) and age- and education-matched healthy human control subjects underwent extensive neuropsychological and visual tracking eye movement tests. At one site, patients and controls also performed the visual tracking tasks while blood-oxygen-level-dependent (BOLD) signals were measured with functional magnetic resonance imaging. Although neither neuropsychological nor visual tracking measures distinguished patients from controls at the level of individual subjects, abnormal BOLD signals were reliably detected in patients. The most consistent changes were localized in white matter regions: anterior internal capsule and superior longitudinal fasciculus. In contrast, BOLD signals were normal in cortical regions, such as the frontal eye field and intraparietal sulcus, that mediate oculomotor and attention functions necessary for visual tracking. The abnormal BOLD signals accurately differentiated chronic mTBI patients from healthy controls at the single-subject level, although they did not correlate with symptoms or neuropsychological performance. We conclude that subjects with persistent post-concussive symptoms can be identified years after their TBI using fMRI and an eye movement task despite showing normal structural MRI and DTI.
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Serguei V
authors.initials: SV
authors.lastname: Astafiev
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Gordon L
authors.initials: GL
authors.lastname: Shulman
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Nicholas V
authors.initials: NV
authors.lastname: Metcalf
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Rengachary
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Christine L
authors.initials: CL
authors.lastname: MacDonald
authors.affiliation: 2 Department of Radiology, University of California , San Diego, San Diego, California.
authors.forename: Deborah L
authors.initials: DL
authors.lastname: Harrington
authors.affiliation: 3 Brain Trauma Foundation , New York, New York.
authors.forename: Jun
authors.initials: J
authors.lastname: Maruta
authors.affiliation: 5 Mallinckrodt Institute of Radiology , St. Louis, Missouri.
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Shimony
authors.affiliation: 3 Brain Trauma Foundation , New York, New York.|4 Department of Neurological Surgery, Weill Cornell Medical College , New York, New York.
authors.forename: Jamshid
authors.initials: J
authors.lastname: Ghajar
authors.affiliation: 2 Department of Radiology, University of California , San Diego, San Diego, California.
authors.forename: Mithun
authors.initials: M
authors.lastname: Diwakar
authors.affiliation: 2 Department of Radiology, University of California , San Diego, San Diego, California.
authors.forename: Ming-Xiong
authors.initials: MX
authors.lastname: Huang
authors.affiliation: 2 Department of Radiology, University of California , San Diego, San Diego, California.
authors.forename: Roland R
authors.initials: RR
authors.lastname: Lee
authors.affiliation: 1 Department of Neurology, Washington University in St. Louis , St. Louis, Missouri.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Corbetta
mesh_terms: D000328:Adult; D020208:Brain Injury, Chronic / Q000473:pathology / Q000503:physiopathology; D053483:Eye Movement Measurements; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D038223:Post-Concussion Syndrome / Q000473:pathology / Q000503:physiopathology; D066127:White Matter / Q000473:pathology / Q000503:physiopathology
keywords: MRI; behavioral assessments; diffusion tensor imaging; traumatic brain injury