title: Anterior commissural white matter fiber abnormalities in first-episode psychosis: a tractography study.
abstract: BACKGROUND
  The Anterior Commissure (AC) is an important interhemispheric pathway that connects contralateral temporal lobes and orbitofrontal areas. The role of the AC is not yet well understood, although abnormalities in this white matter tract have been reported in patients diagnosed with chronic schizophrenia. However, it is not known whether changes in the AC are present at earlier stages of the disease.
  
  
  METHODS
  Diffusion Magnetic Resonance Images (dMRI) were acquired from 17 First Episode Schizophrenia Patients (FESZ) and 20 healthy controls. The AC was reconstructed using a streamline tractography approach. DMRI measures, including Fractional Anisotropy (FA), Trace, Axial Diffusivity (AD) and Radial Diffusivity (RD) were computed in order to assess microstructural changes in the AC.
  
  
  RESULTS
  FA was reduced, while trace and RD showed increases in FESZ. AD did not show differences between groups.
  
  
  CONCLUSIONS
  The observed changes in these dMRI measures, namely reductions in FA and increases in trace and RD, without changes in AD, likely point to myelin abnormalities of this white matter tract, and provide evidence of white matter pathology extant in the early phases of schizophrenia.
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. Electronic address: zora@bwh.harvard.edu.
authors: Zora
authors: Z
authors: Kikinis
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Jennifer
authors: J
authors: Fitzsimmons
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Chandler
authors: C
authors: Dunn
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Mai-Anh
authors: MA
authors: Vu
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Psychiatry Department, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA; Neurology Department, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
authors: Nikos
authors: N
authors: Makris
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Sylvain
authors: S
authors: Bouix
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, USA; Department Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors: Jill M
authors: JM
authors: Goldstein
authors: Beth Israel Deaconess Medical Center, Massachusetts Mental Health Center, Public Psychiatry Division, Harvard Medical School, Boston, MA,USA.
authors: Raquelle I
authors: RI
authors: Mesholam-Gately
authors: Psychiatric and Neurodevelopmental Genetics Unit, Department of Psychiatry and Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA; Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
authors: Tracey
authors: T
authors: Petryshen
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; VA Boston Healthcare System, Brockton, MA, USA.
authors: Elisabetta C
authors: EC
authors: Del Re
authors: Beth Israel Deaconess Medical Center, Massachusetts Mental Health Center, Public Psychiatry Division, Harvard Medical School, Boston, MA,USA.
authors: Joanne
authors: J
authors: Wojcik
authors: Beth Israel Deaconess Medical Center, Massachusetts Mental Health Center, Public Psychiatry Division, Harvard Medical School, Boston, MA,USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors: Larry J
authors: LJ
authors: Seidman
authors: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Marek
authors: M
authors: Kubicki
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D016880:Anisotropy; D001921:Brain / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000188:drug therapy / Q000473:pathology*; D066127:White Matter / Q000473:pathology*; D055815:Young Adult
keywords: Anterior commissure (AC); Diffusion Tensor Magnetic Resonance Imaging (dMRI); First-episode schizophrenia; Fractional anisotropy (FA); Radial diffusivity (RD); Tractography