title: White matter abnormalities in bipolar disorder and schizophrenia detected using diffusion tensor magnetic resonance imaging.
abstract: OBJECTIVE
  Strong qualitative and quantitative evidence exists of white matter abnormalities in both schizophrenia and bipolar disorder (BD). Diffusion tensor imaging (DTI) studies suggest altered connectivity in both disorders. We aim to address the diagnostic specificity of white matter abnormalities in these disorders.
  
  
  METHODS
  DTI was used to assess white matter integrity in clinically stable patients with familial BD (n = 42) and familial schizophrenia (n = 28), and in controls (n = 38). Differences in fractional anisotropy (FA) were measured using voxel-based morphometry and automated region of interest analysis.
  
  
  RESULTS
  Reduced FA was found in the anterior limb of the internal capsule (ALIC), anterior thalamic radiation (ATR), and in the region of the uncinate fasciculus in patients with BD and those with schizophrenia compared with controls. A direct comparison between patient groups found no significant differences in these regions. None of the findings were associated with psychotropic medication.
  
  
  CONCLUSIONS
  Reduced integrity of the ALIC, uncinate fasciculus, and ATR regions is common to both schizophrenia and BD. These results imply an overlap in white matter pathology, possibly relating to risk factors common to both disorders.
authors.affiliation: Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh, UK. jess.sussmann@ed.ac.uk
authors.forename: Jessika E
authors.initials: JE
authors.lastname: Sussmann
authors.forename: G Katherine S
authors.initials: GK
authors.lastname: Lymer
authors.forename: James
authors.initials: J
authors.lastname: McKirdy
authors.forename: T William J
authors.initials: TW
authors.lastname: Moorhead
authors.forename: Susana
authors.initials: S
authors.lastname: Muñoz Maniega
authors.forename: Dominic
authors.initials: D
authors.lastname: Job
authors.forename: Jeremy
authors.initials: J
authors.lastname: Hall
authors.forename: Mark E
authors.initials: ME
authors.lastname: Bastin
authors.forename: Eve C
authors.initials: EC
authors.lastname: Johnstone
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Lawrie
authors.forename: Andrew M
authors.initials: AM
authors.lastname: McIntosh
mesh_terms: D000328:Adult; D016880:Anisotropy; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000473:pathology; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D001931:Brain Mapping; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D012559:Schizophrenia / Q000175:diagnosis* / Q000473:pathology