title: Morphometric brain characterization of refractory obsessive-compulsive disorder: diffeomorphic anatomic registration using exponentiated Lie algebra.
abstract: BACKGROUND
  Few studies have used neuroimaging to characterize treatment-refractory obsessive-compulsive disorder (OCD). This study sought to explore gray matter structure in patients with treatment-refractory OCD and compare it with that of healthy controls.
  
  
  METHODS
  A total of 18 subjects with treatment-refractory OCD and 26 healthy volunteers were analyzed by MRI using a 3.0-T scanner and voxel-based morphometry (VBM). Diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) was used to identify structural changes in gray matter associated with treatment-refractory OCD. A partial correlation model was used to analyze whether morphometric changes were associated with Yale-Brown Obsessive-Compulsive Scale scores and illness duration.
  
  
  RESULTS
  Gray matter volume did not differ significantly between the two groups. Treatment-refractory OCD patients showed significantly lower gray matter density than healthy subjects in the left posterior cingulate cortex (PCC) and mediodorsal thalamus (MD) and significantly higher gray matter density in the left dorsal striatum (putamen). These changes did not correlate with symptom severity or illness duration.
  
  
  CONCLUSIONS
  Our findings provide new evidence of deficits in gray matter density in treatment-refractory OCD patients. These patients may show characteristic density abnormalities in the left PCC, MD and dorsal striatum (putamen), which should be verified in longitudinal studies.
authors.affiliation: Department of Psychiatry, West China Hospital, Sichuan University, Chengdu, Sichuan, PR China.
authors.forename: Wanjie
authors.initials: W
authors.lastname: Tang
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Huang
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Jiang
authors.forename: Fei
authors.initials: F
authors.lastname: Li
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wang
authors.forename: Taolin
authors.initials: T
authors.lastname: Chen
authors.forename: Jinhui
authors.initials: J
authors.lastname: Wang
authors.forename: Qiyong
authors.initials: Q
authors.lastname: Gong
authors.forename: Yanchun
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000378:metabolism / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D009771:Obsessive-Compulsive Disorder / Q000378:metabolism* / Q000473:pathology*; D017397:Prefrontal Cortex / Q000378:metabolism / Q000473:pathology; D011699:Putamen / Q000378:metabolism / Q000473:pathology; D013788:Thalamus / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
keywords: CSTC; DARTEL; DBS; FWE; HARS; HDRS; Hamilton Anxiety Rating Scale; Hamilton Depression Rating Scale; MD; MRI; OCD; Obsessive–compulsive disorder; PCC; Posterior cingulate cortex; ROI; Refractory; VBM; Y-BOCS; Yale-Brown Obsessive Compulsive Scale; cortical-striatal-thalamic-cortical; deep brain stimulation; diffeomorphic anatomical registration using exponentiated Lie algebra; family-wise error; magnetic resonance imaging; mediodorsal thalamus; obsessive-compulsive disorder; posterior cingulate cortex; region of interest; voxel-based morphometry