Proton spectroscopic imaging of the thalamus in treatment-naive pediatric obsessive-compulsive disorder.
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.
Fitzgerald
K D
KD
Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan, USA.
Moore
G J
GJ
Paulson
L A
LA
Stewart
C M
CM
Rosenberg
D R
DR
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*
D010725:Phosphocreatine; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline