关键词: 超早期脑缺血, 超声灌注成像, 血流动力学, SD大鼠

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