早期缺血性脑卒中的CT灌注及血管成像分析

Analysis of CT perfusion and CT angiograph in early ischemic stroke

目的探讨CT灌注及血管成像分析对早期缺血性脑卒中的诊断价值。方法选取2014年1月至2016年3月中信惠州医院41例早期脑缺血卒中患者进行CT平扫、CT灌注和CT血管成像检查,比较CT灌注和CT血管成像诊断早期缺血性脑卒中的敏感性和准确性。结果 1 CT平扫示患者早期大脑梗死区提示有低密度病灶,CT平扫的敏感性为57.7%,特异性为100.0%,诊断准确性为73.2%;而CT灌注成像可见缺血脑组织,脑血流量(CBF)、脑血容量(CBV)下降,平均通过时间(MTT)、峰值时间(TTP)延长。其中MTT和CBF的敏感性和诊断准确性均明显高于CT平扫,颈内动脉CT成像敏感性明显低于CT灌注成像,准确性明显低于CT平扫和CT灌注成像,颅内动脉成像敏感性和诊断准确性明显高于CT平扫,差异均有统计学意义(P<0.05),而特异度几种方式比较差异均无统计学意义(P>0.05);2 CT灌注成像显示患者半暗带区CBF、CBV、MTT、TTP、PE百分比值(rCBF、rCBV、rMTT、rTTP、rPE)与梗死区比较差异均有统计学意义(P<0.05),具体表现在rCBF、rCBV、rPE明显高于梗死区,rMTT和rTTP明显低于梗死区;3可见半暗带区和梗死区rCBF与rCBV呈正相关,rCBF与rMTT、rMTT与rCBV、rTTP与rRE呈负相关(P<0.05)。结论 CT灌注成像对早期缺血性脑卒中诊断敏感性高,各个参数能够较为准确检测到大脑早期缺血引起组织变化情况,故可作为早期缺血性脑卒中的重要检查手段。

Objective To evaluate the diagnostic value of CT perfusion and CT angiograph in the early diagnosis of ischemic stroke. Methods CT plain scan, CT perfusion and CT angiography were performed in 41 patients with early cerebral ischemic stroke in CITIC Huizhou Hospital from Jan. 2014 to Mar. 2016. The sensitivity and diagnostic accuracy of CT perfusion and CT angiography were compared. Results 1 CT plain scan showed low-density lesions in patients with early cerebral infarction（sensitivity 57.7%, specificity 100.0%, diagnostic accuracy 73.2%）, whereas CT perfusion showed decreased cerebral blood flow（CBF） and cerebral blood volume（CBV） in ischemic brain tissue, as well as prolonged mean transit time（MTT） and time to peak（TTP）. The sensitivity and diagnostic accuracy of MTT and CBF were significantly higherthan those of CT, and the difference was statistically significant（P〈0.01）. The sensitivity of CT angiograph of carotid artery was significantly lowerthan that of CT perfusion（P〈0.05）, and the accuracy was significantly lowerthan that of CT plain scan and CT perfusion（P〈0.05）. The sensitivity and diagnostic accuracy of CT angiograph of intracranial artery were significantly higherthan that of CT plain scan（P〈0.05）. There were no significant differences in specificity between the different ways（P〉0.05）. 2 There were significant differences in rCBF, rCBV, rMTT, rTTP, rPE between infarct area and semi dark zone（P〈0.05）, with rCBF, rCBV, rPE significantly higherand rMTT,rTTP significantly lowerin semi dark zone than in infarct area. 3 There was a positive correlation between rCBF and rCBV in the semi dark zone and the infarct area, and a negative correlation between RCBF and rMTT, rMTT and rCBV,rTTP and rRE（P〈0.05）. Conclusion CT perfusion imaging has high sensitivity in the early diagnosis of ischemic stroke. Each parameterof CT perfusion can accurately detect the tissue changes caused by early cerebral ischemia. Therefore, it can be used as an important mean of examination forearly ischemic stroke.