title: MTR abnormalities in subjects at ultra-high risk for schizophrenia and first-episode schizophrenic patients compared to healthy controls.
abstract: BACKGROUND
  Neuroimaging studies have suggested gray (GM) and white matter (WM) abnormalities in early stages of schizophrenia. We aimed at evaluating subtle parenchymal alterations in individuals at ultra-high risk (UHR) for transition into psychosis and first-episode schizophrenic (FES) patients by measuring the magnetization transfer ratio (MTR).
  
  
  METHODS
  In a cross-sectional study magnetization transfer images and high-resolution volumetric T1-weighted images were acquired in 70 age- and gender-matched subjects (25 UHR subjects, 16 FES patients and 29 controls) in a 1.5Tesla scanner. Following normalization of MTR-maps the intensity histograms were analyzed by performing a Kruskal-Wallis-test.
  
  
  RESULTS
  Gray matter MTR decreases were depicted in UHR subjects solely, involving the cingulate gyrus and precentral cortex. WM MTR alterations were more pronounced in FES than in UHR patients and exclusively affected the frontal lobe bilaterally. In addition, UHR subjects showed bilateral MTR decreases at the stria terminalis though statistically significant only on the left side (p=0.018.)
  
  
  CONCLUSIONS
  Our results indicate GM affection earlier on during disease progression as well as cumulative WM affection within frontal lobes during transition from UHR to FES. MTR reductions at the stria terminalis of UHR patients points to the involvement of the extended amygdala in the prodromal disease stage.
authors.affiliation: Department of Neuroradiology, Charité Campus Mitte, 10117 Berlin, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Bohner
authors.forename: Denny
authors.initials: D
authors.lastname: Milakara
authors.forename: Henning
authors.initials: H
authors.lastname: Witthaus
authors.forename: Jürgen
authors.initials: J
authors.lastname: Gallinat
authors.forename: Michael
authors.initials: M
authors.lastname: Scheel
authors.forename: Georg
authors.initials: G
authors.lastname: Juckel
authors.forename: Randolf
authors.initials: R
authors.lastname: Klingebiel
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D011569:Psychiatric Status Rating Scales; D012306:Risk; D012559:Schizophrenia / Q000473:pathology*; D018709:Statistics, Nonparametric; D055815:Young Adult