Study of regional cerebral blood flow in obsessive compulsive disorder patients with SPM and ROI method

Objective To investigate the alternations in regional cerebral blood flow (rCBF) in obsessive compulsive disorder (OCD) patients using statistical parametric mapping (SPM). Methods rCBF measurements using 99Tc m-ethyl cysteinate dimer (ECD) SPECT was performed on 14 OCD patients and 23 age-matched healthy volunteers. The rCBF distribution was compared between these two groups with SPM under the conditions of increased and decreased perfusion, and with regions of interest (ROIs) using cerebral template. P value was set at 0.01 level. Results SPM analysis showed that rCBF decreased in cerebral areas including bilateral putamen, superior temporal gyrus and precuneus, and right orbital gyrus, superior and middle frontal gyrus, and left temporo-occipital lobule and superior parietal gyrus, and vermis. rCBF was also increased in left inferior frontal gyrus and posterior cingulate gyrus. With ROIs method, rCBF was decreased in righ anterior frontal, temporo-parietal lobule and left temporo-occipital lobule. Conclusions Our study supports the viewpoint that rCBF abnormality of frontostriatal circuits is involved in OCD patients. SPM method is a forceful tool in analyzing cerebral regional characters.