CT灌注成像技术对颈动脉狭窄支架置入术的疗效评价

目的:使用CT灌注成像(CTP)评价颈动脉支架置入术后脑血流灌注的变化.方法:23例颈动脉狭窄病人分为有症状组14例和无症状组9例,均经脑血管数字减影血管造影/CT血管造影术确诊为单侧颈内动脉中或重度狭窄.对全部病人行颈动脉支架置入术,共置入支架23枚,术前及术后7 d对所有病人行脑CTP检查.分别比较2组术前、术后7 d的CTP常用指标脑局部血流量、局部脑血容量、局部平均通过时间及相对达峰时间.结果:2组术后rTTP、rMTT时间均缩短但差异无统计学意义(P>0.05),而rCBF、rCBV差异均有统计学意义(P<0.05~P<0.01).患侧rTTP、rMTT较健侧延长,rCBF较健侧降低(P<0.01),rCBV与健侧比较差异无统计学意义(P>0.05).术后7 d CTP成像,rCBF、rCBV患侧与健侧比较差异均无统计学意义(P>0.05),患侧rTTP、rMTT较前有所好转(P<0.05和P<0.01),但与健侧比较仍有明显延迟(P<0.01).结论:CTP可以相对准确地反映颈动脉狭窄病人支架成形术前后的脑血流动力学状况,可成为头颈部动脉狭窄支架置入术后脑血流动力学改变的无创性评价方法,rTTP是评价早期缺血以及侧支循环代偿能力非常敏感的指标.

Application value of CT perfusion imaging in evaluating the efficacy of the carotid artery stenting

Objective:To evaluate the blood perfusion change of cerebral after carotid artery stenting using CT perfusion imaging(CTP).Methods:Twenty-three patients with carotid stenosis were divided into the symptomatic group(n=13) and asymptomatic group(n=10).The medium or severe unilateral internal carotid artery stenosis patients were diagnosed using the cerebral digital subtraction angiography/CT angiography.All patients were treated with the carotid artery stenting,two groups was not,statistically significaat(P>0.05) and examined using brain CTP before operation and after 7 days of operation.The relative regional cerebral blood flow(rCBF),relative regional cerebral blood volume(rCBV),relative regional mean transit time(rMTT) and relative regional time to peak(rTTP) between two groups were compared after 7 days of operation.Results:The postoperative time of rTTP and rMTT shortened,but the diffence between the two groups was not statistically significant(P>0.05),the postoperative time of rCBF,rCBV was statistically significant(P<0.05 to P<0.01).Compared with the healthy side,the time of rTTP and rCBV prolonged,and the time of rCBF increased in affected side(P<0.01).The difference of the time of rCBV between the healthy side and affected side was not statistically significant(P>0.05).The CTP imaging after 7 days of operation showed the differences of the time of rCBF and rCBV between the healthy side and affected side were not statistically significant(P>0.05).The rTTP and rMTT in affected side were improved after operation(P<0.05 and P<0.01),and which obviously delayed compared with the healthy side(P<0.05).Conclusions:The CTP maybe accurately reflect the cerebral hemodynamic status in patients with carotid artery stenosis before and after stenting,which can be used as a noninvasive evaluating method for cerebral hemodynamic change after carotid artery stenting.The rTTP is a very sensitive index for evaluating early ischemia and compensator capacity of collateral circulation.