title: Changes in gray matter volume and white matter microstructure in adolescents with obsessive-compulsive disorder.
abstract: BACKGROUND
  There is a paucity of neuroimaging data in pediatric-onset obsessive-compulsive disorder (OCD). This multimodal neuroimaging study aimed to identify structural gray (GM) and white matter (WM) microstructure changes in pediatric OCD.
  
  
  METHODS
  We obtained structural and diffusion tensor magnetic resonance images from 26 OCD patients and 26 matched healthy adolescents. We carried out a series of image analyses including, volumetric and shape analysis of subcortical gray structures, as well as voxel-based morphometry on GM volume and fractional anisotropy of the WM.
  
  
  RESULTS
  Patients had increased GM volume in the caudate bilaterally and right putamen. Shape analyses revealed specific hypertrophy of the dorsal caudate in pediatric OCD. The striatum was larger in healthy boys compared with healthy girls, whereas such a gender effect was not seen in the OCD group. OCD subjects showed higher fractional anisotropy values in left inferior longitudinal fasciculus, bilateral superior longitudinal fasciculus, right inferior fronto-occipital fasciculus, bilateral corticospinal tract, corpus callosum splenium and genu, bilateral forceps major, bilateral forceps minor, left cingulum, and right uncinate fasciculus. OCD symptom severity was positively correlated with GM volume in right insula, posterior orbitofrontal cortex, brainstem, and cerebellum and inversely correlated with widespread reduction in cortical GM volume. Furthermore, symptom severity positively correlated with increased WM fractional anisotropy in various WM tracts, including the anterior limb of the internal capsule.
  
  
  CONCLUSIONS
  Adolescents with OCD had a wide range of GM and WM changes compared to healthy control subjects that are broadly consistent with those identified in the adult OCD literature but are more extensive.
authors: Brain Mapping Research Centre, Tehran University of Medical Sciences, Tehran, Iran.
authors: Mojtaba
authors: M
authors: Zarei
authors: David
authors: D
authors: Mataix-Cols
authors: Isobel
authors: I
authors: Heyman
authors: Morgan
authors: M
authors: Hough
authors: Joanne
authors: J
authors: Doherty
authors: Linda
authors: L
authors: Burge
authors: Louise
authors: L
authors: Winmill
authors: Sunita
authors: S
authors: Nijhawan
authors: Paul M
authors: PM
authors: Matthews
authors: Anthony
authors: A
authors: James
mesh_terms: D000293:Adolescent; D001479:Basal Ganglia / Q000473:pathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D002648:Child; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D009771:Obsessive-Compulsive Disorder / Q000473:pathology* / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D013223:Statistics as Topic