title: Voxel- and atlas-based analysis of diffusion tensor imaging may reveal focal axonal injuries in mild traumatic brain injury -- comparison with diffuse axonal injury.
abstract: BACKGROUND
  The diagnosis and management of mild traumatic brain injury (MTBI) continue to be subjects of debate, with varying opinions regarding the extent to which tissue-based impairments versus the impacts of other stressors cause ongoing disability. Detecting areas of the brain with abnormalities that can explain symptoms and behavior in patients with MTBI is important in order to confirm the diagnosis of MTBI.
  
  
  METHODS
  In this study, we calculated diffusion maps from results of diffusion tensor imaging (DTI) performed in an apparently healthy control group. We then compared these maps with those of patients with MTBI (MTBI group) or diffuse axonal injury (DAI group). All diffusion maps were normalized to the International Consortium for Brain Mapping atlas for atlas-based analysis and were segmented and normalized by the Diffeomorphic Anatomical Registration Through Exponentiated Lie tool in SPM8 to reduce misregistration.
  
  
  RESULTS
  All diffusion measures in the DAI group were lower than in the control group. There were significant differences in the body and splenium of the corpus callosum, fornix and right cerebral peduncle in the DAI group compared with the control group (P<.001). The MTBI group had higher axial diffusivity than the control group in the right corticospinal tract, left medial lemniscus, left inferior cerebellar peduncle, bilateral anterior limb of the internal capsule, right anterior corona radiata, bilateral cingulum (cingulate gyrus) and left superior frontooccipital fasciculus (P<.05).
  
  
  CONCLUSIONS
  Voxel- and atlas-based analysis of DTI might suggest that patients with MTBI have focal axonal injury and that the pathophysiology is significantly different from that of DAI. These findings will help in the diagnosis of patients with MTBI.
authors.affiliation: Department of Radiological Sciences, Graduate School of Human Health Science, Tokyo Metropolitan University, Tokyo 116-8551, Japan.
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kasahara
authors.forename: Keiji
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Abo
authors.forename: Atsushi
authors.initials: A
authors.lastname: Senoo
mesh_terms: D000063:Accidents, Traffic; D000328:Adult; D001642:Bicycling / Q000293:injuries; D001930:Brain Injuries / Q000175:diagnosis / Q000503:physiopathology; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D020833:Diffuse Axonal Injury / Q000175:diagnosis* / Q000503:physiopathology; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged