家犬急性缺血性脑梗死模型炫速双源CT灌注成像超早期诊断实验研究

目的 探讨炫速双源CT灌注成像在急性脑梗死超早期诊断中的价值,观察缺血再灌注对于神经元凋亡的影响。方法 健康杂种家犬12只,通过介入手段建立犬急性缺血性脑梗死模型,均在栓塞前以及栓塞后1、2、3、4、5、6 h,进行CT平扫检查、炫速双源CT脑灌注成像(Computed tomography perfusion,CTP)。测定梗死区和对侧正常对照区的血流灌注值脑血流量(cerebral blood flow,CBF),脑血流容积(cerebral blood flow volume, rCBV),灌注达到峰值时间(Time to peak,TTP)等,并获得相应脑灌注CT成像,做完CT检查后24 h后处死动物,取其脑组织行病理检查。结果 12只犬均成功建立脑梗死模型,CTP检查示11只梗死区CBF、CBV较对侧减少,TTP、MTT较对侧延长,1只无明显的变化。1 h组及2 h组ΔCBF、ΔCBV下降较明显,具有统计学意义,1-6h组ΔTTP数值具有统计学意义;24 h后实验动物均未死亡,通过术后病理检查发现家犬脑组织出现梗死灶,直径约2.3～8.3 mm。结论 CT灌注成像能快速、准确反映犬急性缺血性脑卒中动物模型缺血半暗带的部位、范围,可以准确判断栓塞血管部位,对早期诊断缺血性卒中和抓住动脉溶栓时机有较好的指导作用。

Ultra-early diagnosis of Hyun-speed dual-source CT perfusion imaging in acute ischemic cerebral infarction in dogs

Objective To investigate the value of Hyun speed dual-source CT perfusion imaging in the early diagnosis of acute cerebral infarction and to observe the effect of ischemia-reperfusion on neuronal apoptosis. Methods Twelve healthy hybrid dogs were established by interventional Methods to establish a model of canine acute ischemic cerebral infarction. CT scan and Hyun speed dual-source CT perfusion imaging were performed before embolization and 1, 2, 3, 4, 5, and 6 h after embolization. To measure the cerebral blood flow, cerebral blood flow volume, and time to peak of the infarction area and the contralateral normal control area, and obtain the corresponding cerebral perfusion CT imaging.In 24 h after the CT examination, the animals were sacrificed and the brain tissues were taken for pathological examination. Results The cerebral infarction model was successfully established in 12 dogs. The CTP examination showed that the CBF and CBV of the 11 infarct areas were decreased compared with the contralateral side. The TTP and MTT were longer than the contralateral side, and there was no significant change in the infarction area. The ΔCBF and ΔCBV decreased significantly in the 1h group and the 2h group, P < 0.05, statistically significant, 2h group was more obvious than 1h group. The ΔTTP values in the 1-6h group were all P<0.05, which was statistically significant.. After 24 hours, the experimental animals did not die. After the pathological examination, the infarcts of the dog brain tissue were found to be about 2.3mm~8.3mm in diameter. Conclusion CT perfusion imaging can quickly and accurately reflect the location and extent of ischemic penumbra in dogs with acute ischemic stroke. It can accurately determine the location of embolized blood vessels. It has an early diagnosis of ischemic stroke and grasping the timing of arterial thrombolysis.