title: Magnetic resonance imaging correlates of first-episode psychosis in young adult male patients: combined analysis of grey and white matter.
abstract: BACKGROUND
  Several patterns of grey and white matter changes have been separately described in young adults with first-episode psychosis. Concomitant investigation of grey and white matter densities in patients with first-episode psychosis without other psychiatric comorbidities that include all relevant imaging markers could provide clues to the neurodevelopmental hypothesis in schizophrenia.
  
  
  METHODS
  We recruited patients with first-episode psychosis diagnosed according to the DSM-IV-TR and matched controls. All participants underwent magnetic resonance imaging (MRI). Voxel-based morphometry (VBM) analysis and mean diffusivity voxel-based analysis (VBA) were used for grey matter data. Fractional anisotropy and axial, radial and mean diffusivity were analyzed using tract-based spatial statistics (TBSS) for white matter data.
  
  
  RESULTS
  We included 15 patients and 16 controls. The mean diffusivity VBA showed significantly greater mean diffusivity in the first-episode psychosis than in the control group in the lingual gyrus bilaterally, the occipital fusiform gyrus bilaterally, the right lateral occipital gyrus and the right inferior temporal gyrus. Moreover, the TBSS analysis revealed a lower fractional anisotropy in the first-episode psychosis than in the control group in the genu of the corpus callosum, minor forceps, corticospinal tract, right superior longitudinal fasciculus, left middle cerebellar peduncle, left inferior longitudinal fasciculus and the posterior part of the fronto-occipital fasciculus. This analysis also revealed greater radial diffusivity in the first-episode psychosis than in the control group in the right corticospinal tract, right superior longitudinal fasciculus and left middle cerebellar peduncle.
  
  
  CONCLUSIONS
  The modest sample size and the absence of women in our series could limit the impact of our results.
  
  
  CONCLUSIONS
  Our results highlight the structural vulnerability of grey matter in posterior areas of the brain among young adult male patients with first-episode psychosis. Moreover, the concomitant greater radial diffusivity within several regions already revealed by the fractional anisotropy analysis supports the idea of a late myelination in patients with first-episode psychosis.
authors: Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland.
authors: Anne
authors: A
authors: Ruef
authors: Logos
authors: L
authors: Curtis
authors: Guenael
authors: G
authors: Moy
authors: Severine
authors: S
authors: Bessero
authors: Maryse
authors: M
authors: Badan Bâ
authors: François
authors: F
authors: Lazeyras
authors: Karl-Olof
authors: KO
authors: Lövblad
authors: Sven
authors: S
authors: Haller
authors: Alain
authors: A
authors: Malafosse
authors: Panteleimon
authors: P
authors: Giannakopoulos
authors: Marco
authors: M
authors: Merlo
mesh_terms: D000328:Adult; D016880:Anisotropy; D001921:Brain / Q000473:pathology*; D016022:Case-Control Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000523:psychology; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology*; D059906:Neuroimaging / Q000379:methods / Q000523:psychology*; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011618:Psychotic Disorders / Q000175:diagnosis / Q000473:pathology*