[18F]FDG PET Study in Obsessive–Compulsive Disorder

Abstract

BackgroundWe used [18F]FDG and PET in patients with obsessive–compulsive disorder (OCD) to evaluate cerebral metabolic involvement before and after treatment with serotonin-specific reuptake inhibitors.MethodIn 11 untreated, drug-free adults, regional cerebral metabolic rate for glucose (rCMRglu) was compared with that of 15 age-matched normal controls.ResultsrCMRglu values were significantly increased in the cingulate cortex, thalamus and pallidum/putamen complex. After treatment a significant improvement in obsessive–compulsive symptoms on the Y-BOC scale (t = 3.59, P < 0.01) was associated with a significant bilateral decrease of metabolism in the whole cingulate cortex (P < 0.001). Clinical and metabolic data were significantly intercorrelated (Kendall's τ = 0.65; P < 0.01).ConclusionsThese findings indicate that OCD is associated with functional hyperactivity of a selected neuronal network and that treatment to reduce symptoms may have a selective neuromodulatory effect on cingulate cortex.