Abstract: Objective　This study aims to evaluate the application of ultrasound perfusion imaging technology in cerebral hemodynamic changes in different types of super-early rat brain ischemia models. Methods　Twenty-two SD rats with locally thinned skulls were randomly divided into the unilateral ligation of right carotid artery group (UI group) and the right middle cerebral artery occlusion group (MCAo group) to establish cerebral ischemia models. Transcranial ultrasound perfusion imaging was performed within 15-30 minutes after modeling to analyze the changes in quantitative perfusion parameters (PI, RT, TTP, WIS, AUC) in the region of interest. The GI quantification software was used to analyze the PI map and TTP map of the right hemisphere before and after modeling in the MCAo group.Results　Comparing quantitative perfusion parameters at two time points before and after modeling only the TTP of the right hemisphere showed significant prolongation in the UI group after modeling (P< 0.05), while TTP was prolonged, PI and AUC were decreased, and WIS was increased in the MCAo group after modeling, with statistically significant differences (P<0.05). After surgery, comparison of the region of interest in the right hemisphere between the two groups revealed statistically significant differences in PI and WIS (P<0.05), but no statistically significant differences were found in RT, AUC and TTP. Comparing the abnormal perfusion area in the right hemisphere of the MCAo group with the whole right hemisphere, all perfusion parameters (RT, TTP, PI, AUC, WIS) showed significant differences (P<0.05). Analysis using GI quantification software found no obvious abnormal blood perfusion areas in the PI and TTP maps of the right hemisphere before modeling in the MCAo group; however, after modeling, obvious abnormal blood perfusion areas were found in the cortex and striatum regions in both PI and TTP maps.Conclusion　Ultrasound perfusion imaging can sensitively detect ischemic areas and quantify the degree of cerebral hypoperfusion in differnt types of super-early rat brain ischemia models. It provides a basis for accurately evaluating the extent and severity of cerebral ischemia and offers precise guidance for creating brain ischemia models.

Key words: super-early cerebral ischemia, ultrasound perfusion imaging, hemodynamics, SD rats

摘要： 目的　探讨超声灌注成像技术在超早期不同类型大鼠脑缺血模型脑血流动力学变化中的应用。方法　将22 只磨薄局部颅骨的SD大鼠随机分至右侧颈总动脉结扎组(UI组)和右侧大脑中动脉闭塞组(MCAo组)制作脑缺 血模型。所有大鼠于造模后15~30 min内行经颅超声灌注成像,分析感兴趣区灌注定量参数(PI、RT、TTP、WIS、 AUC)变化规律,并使用GI量化软件对MCAo组造模前后右侧半脑的PI图及TTP图进行分析。结果　组内比较 发现,UI组造模后仅右脑TTP延长(P<0.05),而MCAo组造模后TTP延长,PI、AUC、WIS降低(P<0.05)。术后两 组大鼠右侧半脑感兴趣区对比发现,PI、WIS的差异存在统计学意义(P<0.05),RT、AUC及TTP的差异无统计学意 义。术后比较MCAo组右脑异常灌注区与右侧半脑发现所有灌注参数(RT、TTP、PI、AUC、WIS)均有显著差异(P< 0.05)。GI量化软件分析发现造模前MCAo组右侧半脑PI及TTP图无明显异常血流灌注区,但造模后PI及TTP 图发现皮质及纹状体区域出现明显的血流灌注异常区。结论　超声灌注成像在不同的超早期大鼠脑缺血模型中 能敏感的发现大脑内的缺血区域,并能计算脑灌注下降的程度,可为准确评估脑缺血的范围及程度提供依据,为脑 缺血模型的制作提供指导。

关键词: 超早期脑缺血, 超声灌注成像, 血流动力学, SD大鼠