创伤后应激障碍海马亚结构功能网络磁共振纵向研究

PTSD is a highly disabled mental illness, whose pathogenesis is still largely unknown. There are also short of objective biomarkers for identifying subjects at high risk of developing PTSD at early phase of trauma.Our previous work showed that hippocampus subregions, such as dentate gyrus(DG) were deficient in structure in subjects with PTSD. So we predict that functions or structure of DG could predict the prevalence of PTSD in trauma victims. Our program applies “pattern separation task”, combining structural magnetic resonance imaging (MRI) and fMRI data, to try to see the activation pattern and structural features of hippocampal DG, which would investigate its prediction power on prevalence of PTSD. We try to obtain the longitudinal trajectory of hippocampal DG functional neural networks in PTSD, by combining the longitudinal MRI data and clinical data when 6-months follow up finished. If we could achieve the anticipated results, people would have a more profound understanding of the pathology of PTSD， further providing evidences for biomarkers for early prediction of PTSD.

创伤后应激障碍(PTSD)是一种高致残率的精神疾病，但其病理机制尚未阐明，更缺乏早期识别易感人群的客观生物学指标。我们在前期横断面研究发现PTSD患者海马齿状回(DG)灰质结构异常，因此推测其功能、结构异常对PTSD 发病有预测作用。本研究选择 “模式区分”研究表型，综合运用磁共振结构像与任务态功能磁共振（fMRI）技术, 在创伤48小时内即对交通事故者海马齿状回功能与灰质结构进行检测，探索其对PTSD发病的预测能力。通过整合纵向磁共振数据及临床数据，探索海马DG功能网络随时间纵向变化的轨迹，寻找 PTSD 特异性的海马功能网络异常。如能够获得预期结果将进一步促进对 PTSD病理机制的深入理解，为寻找早期预测指标提供依据。

交通事故伤者在外伤恢复后仍会反复出现闯入性症状群等PTSD症状，其患PTSD风险高。探索交通事故急性期(48小时内)伤者脑内功能网络变化，将有助于阐明PTSD发病机制。本研究在交通事故急性期纳入伤者，在研究基线采集其磁共振数据及临床数据，并对伤者进行6月随访判断其预后转归。结果发现交通事故伤者在事故急性期海马亚结构功能网络即出现异常，异常程度与随访时PTSD症状严重程度显著相关。提示交通事故这一重大应激事件能在极早期即改变海马亚结构功能网络的活动，进而影响疾病预后。本项目在新冠爆发后，纳入了援鄂精神科医生及未暴露于新冠的健康精神科医生对照，在基线时采集其临床及磁共振数据。3月后对援鄂医生磁共振及临床数据进行随访。初步结果提示援鄂医生在疫情一线工作后其左侧岛叶-左侧额上回功能连接出现异常，共情能力可预测该功能连接的异常程度。提示共情能力弱的医生在经历重大应激后其脑内功能更容易受到损伤。