Comparing brain magnetic resonance spectroscopy findings of pediatric treatment-naive obsessive-compulsive disorder patients with healthy controls.

Objective: It is believed that biochemical alterations in different brain regions are involved in the pathophysiology of obsessive-compulsive disorder (OCD) in children and adolescents. The aim of this study was to explore possible metabolic variations between pediatric OCD cases and healthy controls in brain regions which were implicated in OCD pathophysiology.

Method: Children and adolescents between 8 and 16 years of age with OCD (n:15) and case matched healthy controls (n:15) were recruited for the study. After detailed clinical and neuropsychological evaluations, all subjects underwent the multiregional magnetic resonance spectroscopy (MRS) procedure with a long echo time (TE:135).

Results: Significantly lower n-acetylaspartate (NAA) ratios in the left inferior frontal gyrus, right occipital grey matter, left anterior cingulate cortex and lower choline (Cho) ratios in right and left anterior cingulate cortex and higher Cho ratio in left lenticular nucleus was observed in the OCD group. Also we found a negative correlation between OCD duration and left insular cortex NAA/Cho ratio.

Conclusion: We found significant metabolic alterations in the brain regions which were implicated in OCD pathophysiology. Lower NAA and Cho ratios in anterior cingulate cortex and lower NAA ratios in the left inferior fronyal gyrus containing lateral orbitofrontal cortex can be possibly related to higher activation in OCD patients. Also further studies of the occipital lobes and insula should be continued in OCD.