title: White matter defects in first episode psychosis patients: a voxelwise analysis of diffusion tensor imaging.
abstract: OBJECTIVE
  Disruptions in white matter structure have consistently been shown in schizophrenia--but mainly in patients in whom the illness is well-established. In order to determine whether white matter abnormalities are present at illness onset, and to minimise the potentially confounding effects of chronic illness and treatment, we used diffusion tensor imaging to study a large cohort of first episode psychotic patients who were medication-naive.
  
  
  METHODS
  Sixty two first episode patients and 54 controls matched on age, sex, years of education and laterality index underwent diffusion tensor imaging. Data were acquired on a GE Signa NVi 1.5 Tesla System. Fractional anisotropy maps were generated on a voxel-by-voxel basis. An optimized voxel-based morphometry technique was conducted with two-stage registration approach. Group differences were examined using a non-parametric statistical method.
  
  
  RESULTS
  The voxelwise analysis revealed four clusters where fractional anisotropy values were significantly lower in patients than controls. These were localised bilaterally to regions of white matter corresponding to superior and inferior longitudinal fasciculus, forceps major, anterior and superior thalamic radiation and corpus callosum.
  
  
  CONCLUSIONS
  Reductions in white matter integrity are present early in the course of the schizophrenia and localised in fascicule that connect brain regions implicated in the disorder.
authors.affiliation: Department of Psychiatry, Marqués de Valdecilla University Hospital, Avenida Valdecilla s/n, University of Cantabria, Spain. rperez@humv.es
authors.forename: Rocío
authors.initials: R
authors.lastname: Pérez-Iglesias
authors.forename: Diana
authors.initials: D
authors.lastname: Tordesillas-Gutiérrez
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Barker
authors.forename: Philip K
authors.initials: PK
authors.lastname: McGuire
authors.forename: Roberto
authors.initials: R
authors.lastname: Roiz-Santiañez
authors.forename: Ignacio
authors.initials: I
authors.lastname: Mata
authors.forename: Enrique Marco
authors.initials: EM
authors.lastname: de Lucas
authors.forename: Fernando
authors.initials: F
authors.lastname: Quintana
authors.forename: Jose L
authors.initials: JL
authors.lastname: Vazquez-Barquero
authors.forename: Benedicto
authors.initials: B
authors.lastname: Crespo-Facorro
mesh_terms: D000293:Adolescent; D000328:Adult; D016880:Anisotropy; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001921:Brain / Q000473:pathology*; D002908:Chronic Disease; D017831:Diagnosis, Dual (Psychiatry); D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000473:pathology*; D012559:Schizophrenia / Q000473:pathology; D019966:Substance-Related Disorders / Q000473:pathology; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents