Voxel-based Morphometry Analysis Of Gray Matter In Patients With Obsessive-compulsive Disorder

Object: The aim of this study was to explore the neuroanatomical changes in patientswith obsessive-compulsive disorder (OCD) using the voxel-based morphometry(VBM) analysis. We also aimed to explore the relationship between the gray mattervolume and Yale Brown Obsessive Compulsive Scale (Y-BOCS) score in patientswith obsessive-compulsive.Method:We recruited19drug-na ve patients with OCD（completed18patients） and20healthy controls(completed18healthy controls), who were matched for age andeducation, to undergo scannings with a3.0T magnetic resonance imaging (MRI)equipment. We employed the voxel-based morphometry (VBM) approach to explorethe neuroanatomical changes in patients. We also investigated the relationshipbetween the gray matter volume and Yale Brown Obsessive Compulsive Scale(Y-BOCS) score in patients with obsessive-compulsive.Result:(1)Compared with healthy controls, patients with OCD showed significantlyincreased gray matter in three point MNI coordinates,but we don’t found specificregions of the brain in ALL template.(2)Compared with healthy controls,patients withOCD showed significantly decreased gray matter in right rolandicoperculum,precentral gyrus, posterior central gyrus, cingulate gyrus, right medial andlateral right lingual gyrus, left right cuneus, calcarine cortex, right middle occipitalgyrus, bilateral occipital gyrus, left middle occipital gyrus, right temporal pole, rightcerebellum and bilateral straight gyrus.(P <0.05, uncorrected).Results aftercorrection for multiple comparisons found in patients with obsessive-compulsivedisorder, gray matter volume reduction of brain regions: the right central sulcus cover,right precentral gyrus, right postcentral gyrus, temporal pole, right middle occipital gyrus, left middle occipital gyrus, right cerebellum and bilateral straight gyrus (P <0.05, corrected).(3)We choose the intracranial volume as a covariant, regressionanalysis between brain gray matter volume of OCD patients and Y-BOCS score.Wefound that the right middle frontal gyrus, left medial frontal gyrus, left superior frontalgyrus, right dorsolateral frontal gyrus, right rolandic operculum,the bilateral inferiororbitofrontal gyrus, the right medial orbitofrontal gyrus, right middle temporal gyrus,the right temporal pole gyrus, cerebellum, left insula of the gray matter volume andY-BOCS score negatively correlated (P <0.05,corrected).(4) We also found adistinct set of overlapped brain regions between brain regions with GMV reductionsand brain regions whose GMV was correlated with Y-BOCS score negatively inpatients with OCD: the right temporal pole, the right cerebellum, and the rightrolandic operculum (the right temporal pole:R2=0.222, the right cerebellum: R2=0.224,the right rolandic operculum:R2=0.177).Conclusion:(1)The gray matter volume in patients with obsessive-compulsivedisorder is abnormal,and mainly show the gray matter volume of the cerebral corticalreduce.(2) In addition to cortical-corpus striatum-thalamic-cortical loop’s brainstructure abnormalities, the back regions of the brain such the parietal lobe, temporallobe, occipital lobe and cerebellum are also play a important role in the pathogenesisof OCD.(3)The gray matter volume decreased is associated with OCD symptomseverity.