Background: Obsessive-compulsive disorder (OCD) is a chronic neural psychological condition. Its pathogenesis is not yet completely understood. This current research used fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) imaging to examine the changes in brain glucose metabolism in patients with OCD during the course of treatment, and analyzed its relationship with clinical efficacy.
Methods: A total of 23 patients with OCD were enrolled and divided into case group 1, consisting of patients who received no drug treatment or those who recently stopped drug treatment for more than five half-life periods (OCD1 group, N=10), and case group 2, consisting of patients who were receiving drug treatment before enrollment (OCD2 group, N=13). Ten healthy volunteers were selected as controls. All patients and healthy controls were subjected to head PET-computed tomography (CT) examination. Seven patients in case group 2 underwent scanning again after 3 months of drug treatment, namely, case group 3 (OCD3 group, N=7). Statistical Parametric Mapping (SPM) 8 software was used to analyze the PET-CT results.
Results: OCD patients had abnormally enhanced glucose metabolism in the medium orbito-frontal region of the brain, and abnormally reduced glucose metabolism in brain areas including the insula, caudate nucleus, and middle temporal gyrus. No changes in brain glucose metabolism related to curative effect was found.
Conclusions: In OCD patients, abnormal brain function may not only be limited to the usual cortico-striato-thalamo-cortical (CSTC) loop model, but may involve a wide range of brain regions simultaneously.
Keywords: Obsessive-compulsive disorder (OCD); brain glucose metabolism; changes before and after drug therapy.