title: Neuroanatomical features in soldiers with post-traumatic stress disorder.
abstract: BACKGROUND
  Posttraumatic stress disorder (PTSD), an anxiety disorder that can develop after exposure to psychological trauma, impacts up to 20 % of soldiers returning from combat-related deployment. Advanced neuroimaging holds diagnostic and prognostic potential for furthering our understanding of its etiology. Previous imaging studies on combat-related PTSD have focused on selected structures, such as the hippocampi and cortex, but none conducted a comprehensive examination of both the cerebrum and cerebellum. The present study provides a complete analysis of cortical, subcortical, and cerebellar anatomy in a single cohort. Forty-seven magnetic resonance images (MRIs) were collected from 24 soldiers with PTSD and 23 Control soldiers. Each image was segmented into 78 cortical brain regions and 81,924 vertices using the corticometric iterative vertex based estimation of thickness algorithm, allowing for both a region-based and a vertex-based cortical analysis, respectively. Subcortical volumetric analyses of the hippocampi, cerebellum, thalamus, globus pallidus, caudate, putamen, and many sub-regions were conducted following their segmentation using Multiple Automatically Generated Templates Brain algorithm.
  
  
  RESULTS
  Participants with PTSD were found to have reduced cortical thickness, primarily in the frontal and temporal lobes, with no preference for laterality. The region-based analyses further revealed localized thinning as well as thickening in several sub-regions. These results were accompanied by decreased volumes of the caudate and right hippocampus, as computed relative to total cerebral volume. Enlargement in several cerebellar lobules (relative to total cerebellar volume) was also observed in the PTSD group.
  
  
  CONCLUSIONS
  These data highlight the distributed structural differences between soldiers with and without PTSD, and emphasize the diagnostic potential of high-resolution MRI.
authors.affiliation: Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Sussman
authors.affiliation: Division of Neurology, Neuroscience and Mental Health Program, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
authors.forename: E W
authors.initials: EW
authors.lastname: Pang
authors.affiliation: Directorate of Mental Health, Canadian Forces Health Services, Ottawa, ON, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Jetly
authors.affiliation: Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada. ben.dunkley@sickkids.ca.
authors.forename: B T
authors.initials: BT
authors.lastname: Dunkley
authors.affiliation: Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
authors.forename: M J
authors.initials: MJ
authors.lastname: Taylor
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology*; D006801:Humans; D007360:Intelligence; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008889:Military Personnel / Q000523:psychology*; D009483:Neuropsychological Tests; D013313:Stress Disorders, Post-Traumatic / Q000473:pathology*