慢性硬膜下血肿外膜的超微结构观察

Ultrastructural observation of the outer membrane of chronic subdural hematoma

目的通过对慢性硬膜下血肿（CSDH）外膜的超微结构观测，探讨CSDH发生和发展的病理学基础。方法收集天津医科大学总医院神经外科自2008年1月至2009年1月间行血肿清除术的8例CSDH患者的外膜标本，其中CT显示血肿密度为低密度2例，等密度2例。高密度2例，混杂密度2例。应用光镜和电镜观察血肿外膜上新生血管的形态和结构。结果光镜下可见血肿外膜大量新生的毛细血管扩张充血。并可见含铁血黄素沉积。电镜下可见血肿外膜组织含大量成纤维细胞和毛细血管；部分毛细血管内皮细胞结构异常，可见损伤内皮细胞，不连续，毛细血管周围常有红细胞渗出；部分毛细血管结构完整，扩张不明显，血管中有微血栓形成、组织中嗜酸性粒细胞增多，颗粒大，部分与成纤维细胞接触，有时可见中性粒细胞和巨噬细胞，成纤维细胞活化明显，呈增殖状态。毛细血管内皮细胞的结构异常和红细胞渗出在血肿密度为高密度者的标本中最为明显。结论CSDH外膜新生血管的形成及反复再出血是CSDH发生和发展过程中的关键因素。

Objective To explore the pathophysiological mechanisim underlying the development and progression of chronic subdural hematoma （CSDH） through an ultrastmctural observation of the outer membrane of CSDH. Methods A total of 8 samples of CSDH outer membrane were obtained from the 8 patients who had uncergone surgery of hematoma removal in our department from January 2008 to January 2009. CT scanning revealed 2 cases of low hematoma density, 2 cases of hematoma isodensity, 2 cases of high hematoma density and 2 cases of mixed hematoma desity. Conventional light microscopy and electron microscopy were used to observe the ultrastructure of the outer membrane. Results Light microscopy showed numerous dilatated and congested macrocapillaries with a wide vascular lumen in the outer membrane of the hematoma capsule. Electron microscopy showed weak, discontinous or partially dissolved endothelial cells in the macrocapillaries. Scattered red blood cells in the extracellular space were found, indicating bleeding within the outer membrane. Eosinophils increased with enlarged granules within the cellular cytoplasm. Neutrophils and macrophages were also present in some specimens. Fibroblasts showed a state of significant proliferation and activation. Conclusions There are abundant newly formed vascular networks in the outer membrane of CSDH. Neomembrane formation, neovascularization and repeated micro-haemorrhages from these fragile new vessels may play a key role in the development and progression of CSDH.