Diffusion tractography magnetic resonance imaging (MRI) can infer changes in network connectivity in patients with traumatic brain injury (TBI), but the pathological substrates of disconnected tracts have not been well defined because of a lack of high-resolution imaging with histopathological validation. We developed an ex vivo MRI protocol to analyze tract terminations at 750-μm isotropic resolution, followed by histopathological evaluation of white matter pathology, and applied these methods to a 60-year-old man who died 26 days after TBI. Analysis of 74 cerebral hemispheric white matter regions revealed a heterogeneous distribution of tract disruptions. Associated histopathology identified variable white matter injury with patchy deposition of amyloid precursor protein (APP), loss of neurofilament-positive axonal processes, myelin dissolution, astrogliosis, microgliosis, and perivascular hemosiderin-laden macrophages. Multiple linear regression revealed that tract disruption strongly correlated with the density of APP-positive axonal swellings and neurofilament loss. Ex vivo diffusion MRI can detect tract disruptions in the human brain that reflect axonal injury.

中文翻译：

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创伤性脑损伤中的纤维束成像与病理学相关性：TRACK-TBI 研究


扩散束成像磁共振成像（MRI）可以推断创伤性脑损伤（TBI）患者网络连接的变化，但由于缺乏具有组织病理学验证的高分辨率成像，断开束的病理基础尚未明确。我们开发了一种离体MRI 方案，以 750 μm 各向同性分辨率分析纤维束末端，然后对白质病理学进行组织病理学评估，并将这些方法应用于一名在 TBI 后 26 天死亡的 60 岁男性。对 74 个大脑半球白质区域的分析揭示了纤维束破坏的异质分布。相关的组织病理学发现了不同的白质损伤，伴有淀粉样前体蛋白（APP）的斑片状沉积、神经丝阳性轴突突起的丧失、髓磷脂溶解、星形胶质细胞增生、小胶质细胞增生和血管周围富含含铁血黄素的巨噬细胞。多元线性回归显示，束破坏与 APP 阳性轴突肿胀和神经丝损失的密度密切相关。离体扩散 MRI 可以检测人脑中反映轴突损伤的束破坏。