A diffusion tensor imaging study of post-traumatic stress disorder related to Wenchuan earthquake before and after treatment

Abstract

Objectives To investigate the altered integrity of white matter in treatment-naive chronic post-traumatic stress disorder (PTSD) patients before and after 12 weeks' treatment with paroxetine and explore the white matter of PTSD patients along with the severity of symptom. Methods Thirteen earthquake-related PTSD patients before and after treatment and 8 traumatized controls recruited from the disaster areas of the Wenchuan earthquake underwent a diffusion tensor imaging (DTI) scan. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the patients before and after treatment and controls were calculated and compared separately. Then, correlation analyses between FA and ADC values within altered brain areas and scores of Clinician-administered PTSD Scale were conducted. Results Compare to traumatized controls, increased ADC values of left superior corona radiate, posterior corona radiate, ventral posterior cingulate (MIN: x=-24,y=-36,z=42; cluster size 2 752 mm3; t=5.154, P<0.05, AlphSim corrected) and right superior corona radiate (MIN: x=26,y=-4,z=20; cluster size 304 mm3; t=3.790, P<0.05, AlphSim corrected) were observed in PTSD patients. And the mean ADC values of left superior corona radiate, posterior corona radiate and ventral posterior cingulate had positively correlation with the severity of symptom within PTSD (r=0.691, P=0.009). After treatment, significantly decreased FA values were observed in the left superior longitudinal fasciculus. And the ADC values of bilateral superior corona radiate were still higher than the traumatized controls. Conclusions The study shows that white matter integrity in the left superior corona radiate, posterior corona radiate and ventral posterior cingulate reflex the severity of PTSD. Short-term treatment with paroxetine could not reverse the abnormities in white matter of PTSD patients. This study reveals the different neuromechanism of formation and recovery in PTSD. Key words: Stress disorder, Post-traumatic; Paroxetine; Diffusion tensor imaging; Fractional anisotropy; Apparent diffusion coefficient