实验性大鼠脑血肿周围脑组织血流变化的CT灌注成像研究  

Dynamic CT perfusion imaging in the study of perihematomal cerebral blood flow after intracerebral hemorrhage in rats

作　　者：周剑[1] 高培毅[1] 李小光[1] 

机构地区：[1]北京市神经外科研究所神经影像中心

出　　处：《中华放射学杂志》2005年第5期538-543,共6页Chinese Journal of 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　探讨建立大鼠脑血肿周围脑组织血流变化的CT灌注成像方法,并对其可行性进行研究。方法　雄性大鼠70只,采用随机数字抽样法将其分为注血组和对照组。分别将40μl新鲜自体血或生理盐水通过微量注射泵注入大鼠右侧尾状核制备脑出血模型。利用CT灌注成像对各组动物模型血肿周围脑组织血流变化进行观察,并与HE染色和红四氮唑(TTC)染色标本对照。通过计算机辅助CT脑灌注成像软件制作灌注CT参数图,并对血肿周围脑组织局部脑血流量(regionalcerebralbloodflow, rCBF)、局部脑血容量(regionalcerebralbloodvolume, rCBV)和平均通过时间(meantransittime, MTT)进行相对值(病侧/健侧)测量。结果　注血组血肿周围脑组织存在不同程度低灌注梯度,血肿周围脑组织局部脑血流量(rCBF)呈波动性改变,在注血后1hrCBF降至最低,随后逐渐回升、下降,分别于注血后6h和24h2次回升至峰值。TTC染色血肿呈黑褐色,血肿周围未见白色梗死区。病理学检查显示在出血灶与正常脑组织间存在过渡带即血肿周围区,周围区内组织疏松,细胞不同程度水肿,星形细胞肿胀,神经细胞变性,出血灶周边可见毛细血管增生及炎细胞浸润。对照组CT灌注成像、TTC染色和病理学检查均未见明显异常。Objective To establish a stable and reproducible experimental method of dynamic CT perfusion imaging in measurements of perihematomal cerebral blood flow after intracerebral hemorrhage (ICH) in rats, and to study its validation. Methods Seventy male Sprague-Dawley rats were randomly divided into ICH groups and sham-operated groups. ICH was produced by microinjection of 40 μl fresh autologous blood or saline into the right caudatum. Dynamic CT perfusion imaging in measurements of regional cerebral blood flow adjacent to hematomas was performed. Then, rats were sacrificed, and the TTC stain and histopathological examination were carried out. The ratios of side-to-side were measured at the regions around the hematomas by personal computer aided mapping. Results The gradient of perihematomal hypoperfusion was revealed by regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) maps in ICH groups. The alternation of rCBF around the hematomas were fluctuated, and rCBF reduction was most pronounced at 1 hour after ICH, then, the rCBF gradually returned, and returned to the peaks at 6 hours and 24 hours after ICH respectively. TTC stain did not show infarction around the hematoma. Histopathological study demonstrated there was a transitional zone between ICH and the normal brain tissue, and the astrocytic swelling and neuronal degeneration were observed in the peri-ICH regions. The inflammatory cell infiltration and capillaries hyperplasia were also seen around the ICH. Conclusion The method of dynamic CT perfusion imaging in measurements of perihematomal cerebral blood flow after intracerebral hemorrhage in rats is stable and accurate. Perfusion CT and its parameter analysis may play an increasing role in delineating the hypoperfusion around hematomas. The experimental method is suitable and validated to the study of secondly injury after ICH in vivo.

关 键 词：血肿周围脑组织 血流变化 大鼠脑 成像研究 cerebral 实验性 CT灌注成像 局部脑血流量 CT脑灌注成像 血液动力学变化 blood TTC染色 病理学检查 平均通过时间 星形细胞肿胀 神经细胞变性 毛细血管增生 成像方法 不同程度 

分 类 号：R816.1[医药卫生—放射医学]