The Study Of Diffusion Tensor Imaging And White Matter Volume In Patients With Schizophrenia

BackgroundSchizophrenia is a common type of severe mental illness,mainly manifested in many brain dysfunctions such as thinking,emotion and cognitive function.Normal brain function depends on the cooperation of multiple brain regions,and the white matter of the brain is an important structure that links the brain regions.Imaging studies suggest that there is abnormal white matter in the brain region in patients with schizophrenia,so it is particularly important to explore the relationship between brain white matter and cognitive impairment and clinical symptoms.ObjectivesThis study used diffusion tensor imaging(DTI)and voxel-based morphometry(VBM)to analyze the white matter of schizophrenic patients and healthy controls.The purpose is to discover the white matter biomarkers associated with clinical symptoms and cognitive impairment.MethodsAccording to the study criteria,45 patients diagnosed as schizophrenia and 48 healthy subjects with similar age,gender and education were selected.The healthy controls were assessed with cognitive function scale and Magnetic Resonance Imaging at the time of enrollment.The patient group performed positive and negative syndrome scale(PANSS),cognitive function scale at baseline and after six weeks of treatment.Voxel-based analysis(VBA)and VBM were used to compare the factional anisotropy(FA),mean diffusivity(MD)and the white matter volume in the two groups.The cognitive function of the two groups was compared and the correlation between local brain regions and the PANSS subitems and cognitive functions was further analyzed.Clinical efficacy were evaluated after six weeks antipsychotic treatment.At the same time,the brain regions which were disfunction at baseline were defined as region of interest.The correlations between change of the white matter volume,FA,MD with the change of PANSS scores and cognitive scale before and after treatment were analyzed.Results1.At baseline,patients showed lower FA in the right anterior cingulum,higher FA in the right external capsule(P<0.005,uncorrected)and significant decreased white matter volume in left frontal lobe,left parietal lobe and bilateral anterior precuneus(P<0.001,uncorrected).After treatment,the FA of right anterior cingulum was significantly lower than before(P<0.005,uncorrected).2.At baseline,the patient’s digital symbols,digit span,and semantic fluency scores were significantly lower than healthy controls(P<0.05).After treatment,the scores of digital symbols,digit span,and semantic fluency of the patients were significantly improved(P<0.05),and the scores of PANSS were significantly decreased(P<0.05).3.At baseline,there was a significant positive correlation between FA of the right external capsule and cognitive factor scores in patients(r=0.488,P=0.025)Conclusions1.The schizophrenia patients had changes in microstructure and morphological structure of the white matter in local brain area.The range of morphological changes was more extensive,and there was a positive correlation between the right external capsule FA and cognitive factors.2.Patients with schizophrenia have extensive cognitive impairment.After short-term antipsychotic treatment,psychiatric symptoms and cognitive impairment are significantly improved.However,the abnormal white matter microstructure and morphological structure of the brain area have not been significantly improved,and even appear to serious.