Brain imaging and behavior
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Brain Imaging Behav · Aug 2018
A preliminary report of cerebral white matter microstructural changes associated with adolescent sports concussion acutely and subacutely using diffusion tensor imaging.
Diffusion tensor imaging (DTI) has demonstrated its utility in detecting microscopic post-concussion cerebral white matter structural changes, which are not routinely evident on conventional neuroimaging modalities. In this study, we compared 10 adolescents with sports concussion (SC) to 12 orthopedically-injured (OI) individuals within 96 h and three months post injury to 12 typically-developing (TD) participants using DTI and volumetric analyses. In terms of volume, no group differences were noted between SC, OI and TD groups at both 96 h and three months post concussion. ⋯ Longitudinally, the SC group demonstrated decreased FA and increased ADC in some areas. The findings highlight the fact that the brain continues to change during the post-injury recovery period, and raises the possibility that adverse changes may result from the neurometabolic cascade that purportedly ensues following SC. DTI may potentially be used to characterize the nature of brain changes that occur following sports-related concussions.
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Brain Imaging Behav · Aug 2018
Posttraumatic stress disorder, symptoms, and white matter abnormalities among combat-exposed veterans.
Posttraumatic stress disorder (PTSD) is associated with abnormalities in functional connectivity of a specific cortico-limbic network; however, less is known about white matter abnormalities providing structural connections for this network. This study investigated whether the diagnosis and symptoms of PTSD are associated with alterations in fractional anisotropy (FA), an index reflecting white matter organization, across six, a priori-defined tracts. White matter FA was quantified by diffusion tensor imaging using 3 T-MRI among 57 male, combat-exposed veterans with no history of moderate to severe head injuries or current alcohol dependence: 31 met criteria for PTSD and 26 were demographically comparable, combat-exposed controls without PTSD. ⋯ Among PTSD + veterans, higher SFOF-FA was associated with greater mood disturbance, dissociative symptoms, and re-experiencing, while lower FA of the uncinate fasciculus (UF) was associated with greater mood disturbance symptoms. Compared to combat-exposed controls without PTSD, veterans with PTSD exhibited higher white matter FA in the SFOF, and a similar tendency in the ACR and CGC, tracts involved in conflict-processing and spatial attention. Prior alcohol use might explain the associations of PTSD with ACR-FA and CGC-FA but not the association with SFOF-FA.