A Study of the Characteristics of the White Matter in Schizophrenic Patients with Defective or Non-defective Symptoms by Diffuse Tensor Imaging

Background: Deficit schizophrenia (DS) is a set of highly homogenous schizophrenia subtypes characterized by primary and persistent negative symptoms. Previous research studies have found that the negative symptoms of schizophrenia are closely related to the impairment of brain structure and function.This study seeks to explore the characteristics of white matter in schizophrenic patients with defective or non-defective symptoms by diffuse tensor imaging (DTI). Methods: According to the defective schizophrenia diagnostic criteria and ICD-10 diagnostic criteria, 30 patients with DS and 30 patients with non-defective schizophrenia (NDS) were enrolled into the research study. DTI imaging data of the white matter were collected by 1.5T magnetic resonance imaging scanner. Then a tract-based spatial statistics (TBSS) method was used to compare the fractional anisotropy (FA) values of the white matter fiber between the two groups. Results: The TBSS analysis results showed that the FA values in the right side of the knee of the corpus callosum (MNI:14,36,-7), right anterior radio-coronal region (MIN:11,34,3) and the right hippocampal region (MIN:30,34,16) in the DS patients were significantly lower compared with those of the NDS patients (all p <0.05). The FA values in the right side of the knee of the corpus callosum was significantly correlated with the time from onset to treatment (r=−0.350, p <0.001), PANSS-negative symptom score (r=−0.157, p =0.007). The FA values in the right anterior radio-crown region was positively correlated with PANSS-negative symptom score (r=0.306, p =0.048). The right hippocampus was negatively correlated with years of education (r=−0.614, p =0.020), duration of antipsychotics using(r=−0.140, p = 0.022), and PANSS-negative symptom score (r=−0.637, p =0.040). Conclusions: In schizophrenic patients with defective symptoms, the structural integrity of white matter fibers was more seriously damaged in the three brain regions including the right knee of the corpus callosum, the right anterior region of the right radiative crown, and the right hippocampus. These white matter lesions are closely related to patient characteristics such as years of education, duration from onset to treatment, duration of anti-psychotic, and severity of negative symptoms.