实验性脑血肿周围组织脑血流变化的CT灌注成像与病理学研究  

CT Perfusion Imaging and Pathological Study of Perihematomal Cerebral Blood Flow in Experimental Intracerebral Hemorrhage

作　　者：周剑[1] 高培毅[1] 李小光[1] 胡平英[1] 

机构地区：[1]北京市神经外科研究所神经影像中心,北京100050

出　　处：《实用放射学杂志》2005年第6期564-568,共5页Journal of Practical Radiology

基　　金：国家自然科学基金资助项目(30370427);北京市自然科学基金资助项目(7032009)。

摘　　要：目的探讨血肿周围组织病理发展进程及其与血肿周围局部脑血流变化的关系。方法采用自体血注射法制备大鼠脑出血模型,对70只大鼠于术后1h、3h、6h、12h、24h、48h和72h7个时间点,利用GELightspeed螺旋CT扫描机灌注成像及计算机辅助系统制作大鼠脑CT灌注参数图,对血肿周围局部脑血流量(rCBF)、局部脑血容量(rCBV)和对比剂平均通过时间(MTT)脑血液动力学参数进行定量测量,并与大鼠脑TTC染色、HE-染色以及超微结构改变进行比较。结果大鼠脑血肿周围可见明显的低灌注梯度,血肿周围rCBF和rCBV显著降低,MTT延长。TTC染色血肿周围未见白色梗死区。HE-染色可见血肿周围区星形细胞肿胀,神经细胞变性、坏死,出血灶周边毛细血管增生伴炎细胞浸润。电镜观察显示,注血早期血肿周围组织星形细胞肿胀,神经细胞改变不明显,髓鞘板层松散;随着注血后时间延长,血肿周围组织损伤呈渐进性加重,星形细胞肿胀明显,神经细胞出现变性,髓鞘板层发生局部断裂、崩解。结论大鼠脑注血早期血肿周围局部脑血流的显著降低引发了血肿周围及远隔区脑组织的缺血性损伤,注血后急性期血肿周围组织细胞损伤呈进行性加重,血肿周围存在涉及多种细胞损伤机制的半暗带。Objective To investigate the progress of pathology of the perihematomal tissue, and to study the relationship between the pathology and the changes of regional cerebral blood flow after intracerebral hemorrhage(ICH) in rats. Methods ICH was produced by microinjection of fresh autologous blood into the right caudatum in rats. CT perfusion imaging and computer-aided mapping in measurements of regional cerebral blood flow adjacent to the hematomas were performed in seventy SD rats at 1h, 3h, 6h, 12h, 24h, 48h and 72h respectively after the ICH. The parameters of regional cerebral blood flow(rCBF), regional cerebral blood volume(rCBV) and mean transit time(MTT) were calculated respectively. After the CT examination, the histopathological examination of TTC, HE and ultrastructure staining were carried out. Results The gradient of perihematomal hypoperfusion was revealed on CT perfusion maps. The rCBF and rCBV around the hematomas reduced pronouncedly, and the MTT delayed. TTC staining did not show infarction around the hematoma. Histopathological study demonstrated the astrocytic swelling and neuronal degeneration in the peri-ICH regions. The inflammory cell infiltration and capillaries hyperplasia were also observed around the ICH. Under the electronic microscope, the pathological changes of ultrastructure were revealed. In the early stage of ICH, there existed swelling of astrocytes, loosing of myelin sheath lamina, but no clear changes occurred in neurons. With the delay of ICH, the cellular injury around hematomas exacerbated progressively, more swelling of astrocytes, slight degeneration of neurons and local fragmentation of myelin sheath lamina were observed.Conclusion The perihemorrhagic and distant ischemic injury can be induced by the pronounced reduction of cerebral blood flow in the early stage of ICH. The cellular injury around hematomas exacerbates progressively in the acute stage of ICH. There is a perihematomal penumbra affecting multiple mechanisms of cellular injury.

关 键 词：脑血肿 脑血流 体层摄影术 X线计算机 灌注 

分 类 号：R743.34[医药卫生—神经病学与精神病学] R814.42[医药卫生—临床医学]