早期缺血性脑梗死的CT灌注及血管成像

目的:探讨多层螺旋CT颈内动脉血管成像(MSCTA)及脑灌注成像(MSCTPI)对早期缺血性脑梗死的应用价值.方法:对24例经临床证实的早期脑梗死患者行MSCTPI及MSCTA检查.通过灌注分析软件生成局部脑血流量(rCBF)、局部脑血容量(rCBV)及平均通过时间(MTT)三种参数的函数图像.MSCTA的扫描数据运用多平面重建(MPR)及最大密度投影(MIP)技术重建颈内动脉.结果:24例患者中,1例MSCTPI检查表现为过度灌注,5例表现为延迟灌注,16例表现为不同程度的灌注不足,2例灌注正常.MSCTA发现24例患者48支颈内动脉中,40支有动脉管壁钙化斑块,37支颈内动脉可见到软斑块.其中32支颈内动脉呈不同程度的狭窄,5支颈内动脉闭塞,11支血管无狭窄.22例在常规CT及MRI图像上为中及大体积梗死(＞5 cm3)的患者,MSCTPI发现与梗死灶相对应的异常灌注区,且均比常规CT及MRI图像上病灶体积大,MSCTA显示颈内动脉呈中重度狭窄或闭塞.2例未发现明显灌注异常的患者,为小体积梗死灶(＜5 cm3),MSCTA显示颈内动脉正常.结论:MSCTPI联合MSCTA可诊断早期缺血性脑梗死,并评价其血液灌注情况,同时还可客观评价缺血区颈内动脉的状况.

Clinical study of multislice computed tomographic perfusion imaging and computed tomographic angiography in acute cerebral infarction

Objective:To explore the applied value of multislice computed tomographic perfusion imaging(MSCTPI) and computed tomographic angiography (MSCTA) in early ischemic cerebral infarction. Methods: MSCTPI and MSCTA was performed in 24 patients who initiailly diagnosed as acute cerebral infarction by clinic in 72 hours. Regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV) and mean transit time (MTT) acquired by the post software.Then MSCTA of internal carotid artery was performed and images including source axial images and reconstructed images by maximum intensity projection( MIP) and multi-planar reconstrution (MPR) methods were also analyzed. Results: Of all 24 cases, one case appeared hyperfusion, 5 cases showed delayed perfusion, 16 cases appeared variant hypoperfusion, and 2 cases had negative results. MSCTA could detect calcific plaque in 40 internal carotid arteries and soft plaque in 37 internal carotid arteries. Stenosis of internal caroid antery was found in 32 of 48 branches in 24 case. 5 branches were occlusive and 11 branches were normal. 22 cases with large or moderate cerebral infarction volume( >5 cm3) confirmed by CT and MRI were smaller than those on MSCTPI as having abnormal perfusion lesions,which were moderate and obvious stenosis and occlusion on MSCTA. In 2 cases with small cerebral infarction volume(<5 cm3), MSCTPI and MSCTA revealed normal. Conclusion: The combination of MSCTPI and MSCTA is very useful in early diagnosing acute cerebral ischemic infarction, evaluating the cerebral hemodynamic information, and assessing internal carotid artery in ischemic regions.