儿童及青少年创伤后应激障碍的杏仁体磁共振波谱研究

MR spectroscopy study of amygdala in pediatric and adolescent patients with post-traumatic stress disorder

目的:运用磁共振波谱成像(MRS)探讨儿童及青少年创伤后应激障碍(PTSD)患者双侧杏仁体的神经生化改变。方法:共纳入38例汶川地震幸存者,包括19例PTSD患者[年龄(13.33±1.91)岁]及19例健康人作为对照[年龄(13.11±1.45)岁)]。运用3.0T磁共振仪进行双侧杏仁体单体素MRS采集,采用LC Model测定各代谢物的绝对浓度,比较其组间差异及左右侧差异,并对各代谢物浓度与PCL-C量表评分进行相关性分析。结果:与对照组比较,PTSD患者左侧杏仁体NAA及Glx浓度增高[分别为(9.402±1.033)和(16.865±2.270)mmol/kg],Cr浓度[(7.243±0.945)mmol/kg]降低;右侧杏仁体NAA及Glx浓度亦显著性增高[分别为(9.270±1.555)和(16.081±0.607)mmol/kg]。此外,对照组左侧杏仁体Cr浓度显著高于右侧,而PTSD组左右侧杏仁体Cr浓度无明显差异。PTSD组右侧Glx浓度与PCL-C评分呈显著正相关(r=0.740,P=0.036)。结论:儿童及青少年PTSD患者双侧杏仁体的神经生化均有异常改变,但左侧更明显;其中Glx的改变可能在PTSD病理生理机制中起关键作用。

Objective： This study was designed to evaluate the neuro-chemical changes in bilateral amygdalae of pediatric and adolescent post-traumatic stress disorder （PTSD） patients with MR spectroscopy （MRS）. Methods： 38 earth quake survivors including 19 PTSD patients with the mean age as （13.33 ± 1.91） years, and 19 healthy controls with the mean age as （13.11±1.45） years. The severity of symptoms was assessed by the PTSD Checklist-Civilian Version （PCL- C）. Single-voxel proton magnetic resonance spectroscopy of bilateral amygdalae was performed on a 3.0 Tesla MR scanner. Spectral data were processed with LC model software to measure the absolute concentrations of different metaholites. The differences of each metaholite between patients and controls as well as left and right side were evaluated. Correlation between the concentration of metaholites and PCL-C scores were also studied. Results.. Compared with the controls, N-aeetylaspartate （NAA） and glutamate/ glutamine （Glx） concentration in the left amygdala increased, which was （9. 402±1. 033） and （ 16. 865± 2. 270） mmol/kg respectively, and ereatine （Cr） concentration decreased （7. 243±0. 945） mmol/kg. Similarly, concentration of N AA and Glx was significantly increased in right amygdala, which was （9. 270 ± 1.555） and （16. 081 ± 0. 607）mmol/kg respectively. In addition, creatine level of left amygdala was significantly higher than that of right amygdala in controls,while no significant difference of Cr concentration was existed in bilateral amygdale of PTSD patients. Glx level of the right amygdala in PTSD patients was found to he positively correlated with PCL-C scores （r= 0. 740, P=0. 036）. Conclusion：The neurobiochemistry of bilateral amygdalae altered in PTSD patients, while the left side was more significant. Changes of glutamatergic system might be the key factor in the pathogenesis of PTSD.