功能磁共振观察烧伤后应激障碍患者静息态脑功能改变

目的 采用低频振幅（ALFF）方法观察烧伤后应激障碍（PTSD）及无应激障碍（Non-PTSD）患者静息态脑功能的改变。方法 对性别、年龄及受教育程度相匹配的PTSD组、Non-PTSD组各16例和正常对照组16名行静息态fMRI（rs-fMRI），应用ALFF方法分析各组大脑自发活动的差异，并对PTSD组存在差异脑区的ALFF值与临床用PTSD诊断量表（CAPS）评分进行相关分析。结果 与正常对照组相比，PTSD组左侧额下回/额中回、右侧额下回/岛叶、双侧海马旁回/前扣带回/额内侧回ALFF增高，左侧舌回、双侧后扣带回/楔前叶ALFF减低，而Non-PTSD组ALFF显著增高的脑区分布于右侧小脑后叶、颞中回、眶额叶、岛叶及左侧海马旁回，Non-PTSD组中未发现ALFF减低脑区；与Non-PTSD组相比，PTSD组右侧丘脑ALFF显著减低，未发现ALFF增高脑区。PTSD患者右侧丘脑平均ALFF值与CAPS分数呈显著负相关（r=-0.637，P=0.008）。结论 烧伤患者静息态下脑活动存在异常，可能与严重烧伤后复杂的应激反应有关。

Resting-state fMRI observation on changes of amplitude of low-frequency fluctuation in burn patients with posttraumatic stress disorder

Objective To explore the changes of amplitude of low-frequency fluctuation (ALFF) in burn patients with and without posttraumatic stress disorder (PTSD) with resting state fMRI (rs-fMRI). Methods Totally 16 PTSD patients (PTSD group), 16 Non-PTSD patients (Non-PTSD group) who had been exposed to a severe burn trauma and 16 healthy controls (control group) matched at age, gender and education level were enrolled, who underwent rs-fMRI. ALFF were calculated on rs-fMRI data to measure the discrepancies of spontaneous brain activity. The correlation between ALFF values of abnormal regions found in PTSD group and clinician administered posttraumatic stress disorder scale (CAPS) was analyzed. Results Compared with control group, increased ALFF was found in PTSD patients in the left inferior frontal gyrus/middle frontal gyrus, right inferior frontal gyrus/insula and bilateral parahippocampal gyrus/anterior cingulate/medial frontal gyrus, while decreased ALFF was found in left lingual gyrus, and bilateral posterior cingutate/precuneus, increased ALFF was found in Non-PTSD group in the right cerebellum posterior lobe, middle temporal gyrus, orbital frontal lobe, insula and left parahippocampal gyrus, while non decreased ALFF area was found in Non-PTSD group. In comparison with Non-PTSD group, decreased ALFF was found in right thalamus in PTSD group. The mean ALFF values of right thalamus in PTSD patients negatively correlated with CAPS scores (r=-0.637, P=0.008). Conclusion Abnormal brain activity exists in burn patients during resting state, which might associate with the complicated response of stress after severe burn trauma.