汶川地震后创伤后应激障碍患者治疗前后的脑弥散张量成像研究

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

目的探讨创伤后应激障碍（post—traumatic stress disorder，PTSD）患者经帕罗西汀治疗前后大脑白质变化情况及其与症状变化的关系。方法利用弥散张量成像（diffusion tensor imaging，DTI）技术对13例汶川地震后PTSD女性患者治疗前（治疗前PTSD组）、经12周帕罗西汀治疗后（治疗后PTSD组）和8名同样经历地震却未患PTsD的女性对照者（对照组）进行检查，比较3组大脑部分各向异性（fractional anisotropy，FA）值和表观弥散系数（apparent diffusion coefficient，ADC）值以及帕罗西汀治疗前后PTSD患者大脑平均FA值和ADC值的变化，将有差异的脑区平均FA值和ADC值与PTSD诊断量表（Clinician—administered PTSD Scale，CAPS）评分进行Pearson相关分析。结果治疗前PTSD组与对照组相比，左侧上辐射冠、左侧后辐射冠、后扣带回腹侧白质（MNI：X=-24，y=-36，z=42；簇大小为2752mm3；t=5．154，P〈0．05，AlphSim矫正）和右侧上辐射冠ADC值升高（MNI：x=26，y=-4，z=20；簇大小为304mm3：t=3．790，P〈0．05，AlphSim矫正）；PTSD组左侧上辐射冠、左侧后辐射冠、后扣带回腹侧白质周围白质脑区ADC值与CAPS评分呈正相关（r=0．691，P=0．009）；与治疗前PTSD组相比，治疗后PTSD组左侧上纵束FA值降低；治疗后双侧上辐射冠ADC值较对照组增高。结论PTSD患者左侧上辐射冠、后辐射冠和后扣带回腹侧周围白质的完整性发生变化，可反映患者症状的严重程度；短期的药物治疗不能完全逆转患者脑白质异常，提示PTSD患者症状形成和恢复的神经机制不同。

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.