Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital, Sichuan University, Chengdu, China.
Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, China.
Hum Brain Mapp. 2021 May;42(7):2147-2158. doi: 10.1002/hbm.25356. Epub 2021 Feb 10.
The hippocampus and amygdala are important structures in the posttraumatic stress disorder (PTSD); however, the exact relationship between these structures and stress or PTSD remains unclear. Moreover, they consist of several functionally distinct subfields/subregions that may serve different roles in the neuropathophysiology of PTSD. Here we present a subregional profile of the hippocampus and amygdala in 145 survivors of a major earthquake and 56 non-traumatized healthy controls (HCs). We found that the bilateral hippocampus and left amygdala were significantly smaller in survivors than in HCs, and there was no difference between survivors with (n = 69) and without PTSD (trauma-exposed controls [TCs], n = 76). Analyses revealed similar results in most subfields/subregions, except that the right hippocampal body (in a head-body-tail segmentation scheme), right presubiculum, and left amygdala medial nuclei (Me) were significantly larger in PTSD patients than in TCs but smaller than in HCs. Larger hippocampal body were associated with the time since trauma in PTSD patients. The volume of the right cortical nucleus (Co) was negatively correlated with the severity of symptoms in the PTSD group but positively correlated with the same measurement in the TC group. This correlation between symptom severity and Co volume was significantly different between the PTSD and TCs. Together, we demonstrated that generalized smaller volumes in the hippocampus and amygdala were more likely to be trauma-related than PTSD-specific, and their subfields/subregions were distinctively affected. Notably, larger left Me, right hippocampal body and presubiculum were PTSD-specific; these could be preexisting factors for PTSD or reflect rapid posttraumatic reshaping.
海马体和杏仁核是创伤后应激障碍（PTSD）的重要结构；然而，这些结构与应激或 PTSD 的确切关系仍不清楚。此外，它们由几个功能上不同的亚区/亚区组成，这些亚区/亚区可能在 PTSD 的神经病理生理学中发挥不同的作用。在这里，我们在 145 名大地震幸存者和 56 名非创伤性健康对照者（HCs）中呈现了海马体和杏仁核的亚区图谱。我们发现，幸存者的双侧海马体和左侧杏仁核明显小于 HCs，而 PTSD 患者（创伤暴露对照组 [TCs]，n = 76）与无 PTSD 幸存者（n = 69）之间没有差异。分析在大多数亚区/亚区中得出了类似的结果，除了在头-体-尾分段方案中，右侧海马体体部、右侧前下托和左侧杏仁核内侧核（Me）在 PTSD 患者中明显大于 TCs 但小于 HCs。PTSD 患者中较大的海马体体部与创伤后时间有关。右侧皮质核（Co）的体积与 PTSD 组症状的严重程度呈负相关，但与 TCs 组的相同测量值呈正相关。PTSD 组和 TCs 组之间 Co 体积与症状严重程度之间的这种相关性存在显著差异。总的来说，我们证明了海马体和杏仁核的普遍较小体积更可能与创伤有关，而不是 PTSD 特异性，并且它们的亚区/亚区受到明显影响。值得注意的是，较大的左侧 Me、右侧海马体体部和前下托是 PTSD 特异性的；这些可能是 PTSD 的预先存在的因素，或反映了创伤后的快速重塑。
