title: Surface anatomical profile of the cerebral cortex in obsessive-compulsive disorder: a study of cortical thickness, folding and surface area.
abstract: BACKGROUND
  Studying the distribution of anatomical abnormalities over the entire cortical surface can help to identify key neural circuits implicated in generating symptoms of neuropsychiatric disorders. There is a significant inconsistency among studies investigating the neuroanatomy of obsessive-compulsive disorder (OCD) because of the confounding influence of co-morbid depression and medication use and the lack of unbiased estimation of whole-brain morphometric changes. It is also unknown whether the distinct surface anatomical properties of thickness, surface area and gyrification, which collectively contribute to grey matter volume (GMV), are independently affected in OCD. Method The cortical maps of thickness, gyrification and surface areal change were acquired from 23 unmedicated OCD patients and 20 healthy controls using an unbiased whole-brain surface-based morphometric (SBM) method to detect regional changes in OCD. Subcortical structures were not assessed in this study.
  
  
  RESULTS
  Patients showed a significant increase in the right inferior parietal cortical thickness. Significant increases in gyrification were also noted in the left insula, left middle frontal and left lateral occipital regions extending to the precuneus and right supramarginal gyrus in OCD. Areal contraction/expansion maps revealed no significant regional differences between the patients and controls. In patients, gyrification of the insula significantly predicted the symptom severity measured using Yale-Brown Obsessive-Compulsive Scale (YBOCS).
  
  
  CONCLUSIONS
  An alteration in the cortical surface anatomy is an important feature of OCD seen in unmedicated samples that relates to the severity of the illness. The results underscore the presence of a neurodevelopmental aberration underlying the pathophysiology of OCD.
authors.affiliation: Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Fan
authors.forename: L
authors.initials: L
authors.lastname: Palaniyappan
authors.forename: L
authors.initials: L
authors.lastname: Tan
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: C
authors.initials: C
authors.lastname: Li
authors.forename: T
authors.initials: T
authors.lastname: Zhang
authors.forename: K
authors.initials: K
authors.lastname: Jiang
authors.forename: Z
authors.initials: Z
authors.lastname: Xiao
authors.forename: P F
authors.initials: PF
authors.lastname: Liddle
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping / Q000379:methods*; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009010:Monte Carlo Method; D009771:Obsessive-Compulsive Disorder / Q000473:pathology*; D009929:Organ Size; D010296:Parietal Lobe / Q000473:pathology; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D055815:Young Adult