Diffusion Tensor Imaging Study Of First-Episode Schizophrenia Based On Tract-Based Spatial Statistics Analysis

Objective:(1)To explore the microstructural change of white matter in first-episode schizophrenia patients bttween patients and healthy people by using diffusion tensor imaging(DTI)based on the tract-based spatia statistics(TBSS)and to provide a neuroimaging basis for the pathophysiology of schizophrenia;(2)To explore the relationship between the abnormalities of white matter fibers and the psychotic symptoms in schizophrenia.Methods:Diagnosis of schizophrenia was determined by Diagnostic and Statistical Manual for Mental Disorders 4th Edition(DSM-IV).DTI scan was acquired on 76 patients and 75 age-,handedness-,gender-and education-matched healthy controls.FSL software was used to preprocess original data and calculate fractional anisotropy(FA).FA was compared between the two groups using TBSS.Correlation analysis was used to explore the relationships between FA value and PANSS scores,SAPS scores and SANS scores of schizophrenia.Results:Compared with the healthy control group,the first-episode schizophrenia group showed decreased FA values in the splenium of corpus callosum,bilateral superior longitudinal fasciculus,anterior limb of internal capsule,uncinate fasciculus,inferior fronto-occipital fasciculus and the left cingulum fasciculus(P<0.05,TFCE and FWE correction).Pearson correlation analysis showed that the FA values of the left inferior fronto-occipital fasciculus was positively correlated with the PANSS scores and SAPS scores(r=0.776 and r=0.677).Conclusions:(1)The first-episode schizophrenia patients showed extensive injured white matter fiber bundles including:splenium of corpus callosum,bilateral superior longitudinal fasciculus,anterior limb of internal capsule,uncinate fasciculus,inferior fronto-occipital fasciculus and the left cingulum fasciculus.This finding suggested microstructural abnormalities of default mode network.TBSS of MR diffusion tensor imaging could discover the damage of white matter microstructure in schizophrenia,and had profoundsignificance for supporting the disconnection of neurodevelopmental hypothesis;(2)There is a significant correlation between the microstructural change of white matte and psychotic symptoms and severity of the disease in first-episode schizophrenia patients,suggested that the change of brain structural may be the biological basis of clinical symptoms of schizophrenia.