title: Proton spectroscopic imaging of the thalamus in treatment-naive pediatric obsessive-compulsive disorder.
abstract: BACKGROUND
  Neurobiological abnormalities in the thalamus, particularly the dorsomedial nucleus of the thalamus, are believed to be involved in the pathophysiology of obsessive-compulsive disorder. Although obsessive-compulsive disorder commonly arises in childhood and adolescence, no prior study has examined the thalamus in pediatric obsessive-compulsive disorder patients.
  
  
  METHODS
  In this study, N-acetyl-aspartate, a putative marker of neuronal viability, creatine/phosphocreatine, and choline levels were measured in the lateral and medical subregions of the left and right thalami using a multislice proton magnetic resonance spectroscopic imaging sequence in 11 treatment-naive, nondepressed obsessive-compulsive disorder outpatients, 8-15 years old, and 11 case-matched control subjects.
  
  
  RESULTS
  A significant reduction in N-acetyl-aspartate/choline and N-acetyl-aspartate/(creatine/phosphocreatine + choline) was observed in both the right and left medial thalami in obsessive-compulsive disorder patients compared with control subjects. The N-acetyl-aspartate/choline and N-acetyl-aspartate/(creatine/phosphocreatine + choline) levels did not differ significantly between case-control pairs in either the left or the right lateral thalamus. Reduction in N-acetyl-aspartate levels in the left medial thalamus was inversely correlated with increased obsessive-compulsive disorder symptom severity.
  
  
  CONCLUSIONS
  These findings provide new evidence of localized functional neurochemical marker abnormalities in the thalamus in pediatric obsessive-compulsive disorder. Our results must be considered preliminary, however, given the small sample size.
authors.affiliation: Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA.
authors.forename: K D
authors.initials: KD
authors.lastname: Fitzgerald
authors.forename: G J
authors.initials: GJ
authors.lastname: Moore
authors.forename: L A
authors.initials: LA
authors.lastname: Paulson
authors.forename: C M
authors.initials: CM
authors.lastname: Stewart
authors.forename: D R
authors.initials: DR
authors.lastname: Rosenberg
mesh_terms: D000293:Adolescent; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology; D002648:Child; D002794:Choline / Q000378:metabolism; D003342:Corpus Striatum / Q000503:physiopathology; D003401:Creatine / Q000378:metabolism; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D009434:Neural Pathways / Q000503:physiopathology; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000503:physiopathology*; D010725:Phosphocreatine / Q000378:metabolism; D012016:Reference Values; D013788:Thalamus / Q000503:physiopathology*
chemical_list: D010725:Phosphocreatine; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline