全脑CT灌注成像在大脑中动脉狭窄或闭塞中的初步应用

Primary application of whole brain CT perfusion in patients with stenosis or occlusion of middle cerebral artery

目的探讨全脑CT灌注成像(CTP)对大脑中动脉狭窄或闭塞的应用价值。方法对20例单侧大脑中动脉(MCA)狭窄或闭塞患者行CT平扫和全脑CTP检查,CTP检查获得脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MTT)、达峰时间(TTP)等参数,同时获得动态CT血管成像(CTA)。结果20例单侧MCA狭窄或闭塞患者,病变侧和对侧CBF和CBV比较差异无统计学意义(P>0.05)。20例患者TTP和MTT均发现与临床症状相对应的灌注异常区,其中16例患者MTT和TTP延迟累及顶叶和半卵圆中心。20例患者病变侧和对侧MTT值分别为(7.05±1.47)s和(4.96±1.00)s,经配对t检验分析差异有统计学意义(t=10.40,P<0.01);病变侧和对侧TTP值分别为(20.04±2.14)s和(17.83±1.89)s,经配对t检验分析差异有统计学意义(t=8.79,P<0.01)。病变侧和对侧CBV和CBF比较差异均无统计学意义。结论64排螺旋CT应用容积穿梭扫描模式全脑CTP,为MCA狭窄或闭塞可提供有价值的脑血流动力学信息和全面显示灌注异常范围,并且重建CTA可以显示血管狭窄或闭塞。

Objective To explore the value of the whole brain CT perfusion （CTP） in patients with stenosis or occlusion of middle cerebral artery （MCA）. Methods Conventional cerebral plain CT and volume Shuttle CTP （8 cm spatial coverage） were performed in 20 patients with unilateral MCA stenosis or occlusion. The parameter maps of cerebral blood flow （CBF）, cerebral blood volume （CBV）, mean transit time （MTT） and time to peak （TTP） were analyzed. Meanwhile dynamic 3D-CT angiography images were obtained. Results In 20 patients with unilateral stenosis or occlusion of MCA, no significant differences were found between the stenosed or occluded side and the eontralateral side assessed in MTT and TTP. MTT and TTP of affected side significantly prolonged compared with contralateral side （[7.05±1.47]s vs [4.96±1.00]s and [20.04±2.14]s vs [17.83±1.89]s, P〈0.01）. No significant difference of CBV nor CBF was detected between the stenosed or occluded side and the contralateral side assessed in 20 patients. Conclusion Volume Shuttle CTP provides valuable information on hemodynamic damage and MCA abnormalities in patients with MCA stenosis or occlusion.