声脉冲辐射力弹性成像联合超声造影评价颈动脉不稳定斑块及对急性脑缺血性事件的预测

Acoustic Radiation Force Impulse Combined with Contrast-enhanced Ultrasound in Evaluating Carotid Artery Unstable Plaque and Prediction of Acute Cerebral Ischemia Events

目的分析声脉冲辐射力弹性成像(ARFI)与超声造影(CEUS)对颈动脉不稳定性斑块(VP)评估价值与急性缺血性脑卒中(CIS)发病风险的预测价值。资料与方法回顾性分析2016年9月-2017年7月于河南科技大学第一附属医院就诊的95例伴有VP患者的临床资料,并根据MRI所证实急性缺血性脑梗死灶分布情况分为有症状组(n=53)和无症状组(n=42),依次进行常规颈动脉超声、ARFI及CEUS检查,测量并比较两组VP的大小、剪切波速度(SWV)、增强强度(EI)。结果有症状组SWV低于无症状组,EI高于无症状组,差异均有统计学意义(P<0.01);两组VP长度及厚度比较,差异均无统计学意义(P>0.05)。受试者工作特性曲线分析显示,当曲线下最大面积为0.688时,SWV截点值=2.190 m/s,其预测CIS发病的灵敏度为66.04%,特异度为76.19%,约登指数0.42;当曲线下最大面积为0.663时,EI截点值=3.785 d B时,预测CIS发病的灵敏度为49.06%,特异度为80.95%,约登指数0.30;联合应用两种技术的灵敏度为84.91%,特异度为71.43%,约登指数0.56;结论 ARFI及CEUS均可对VP进行量化分析。斑块的SWV越慢、EI越高,其稳定性越低,故可为高危人群的识别以及对CIS发病预测提供客观的影像学依据。ARFI与CEUS联合应用使预测价值明显提高。

Purpose To analyze the value of acoustic radiation force impulse （ARFI） elastography and contrast-enhanced ultrasonography （CEUS） in assessing carotid artery vulnerable plaque （VP） and in predicting risks of cerebral ischemic stroke （CIS）. Materials and Methods The clinical data of 95 patients with VP who were treated in the First Affiliated Hospital of Henan Universityof Science and Technology from September 2016 to July 2017 were retrospectively analyzed. They were divided into symptomatic group（n=53） and asymptomatic group （n=42） as per the distribution condition of acute ischemic cerebral infarction as confirmed by MRI. Routinecarotid artery ultrasound, ARFI, and CEUS examination were successively performed to measure and compare VP size, shear wave velocity（SWV）, and enhanced intensity （EI） between the groups. Results SWV in the symptomatic group was lower than that of the asymptomaticgroup, and EI was higher than that of the asymptomatic group, the difference of which was statistically significant （P〈0.01）. The differencein terms of VP length and thickness between the two groups showed no statistical significance （P〉0.05）. According to ROC curve analysis,when the maximum area under the curve （AUC） was 0.688, SWV cutoff value was 2.190 m/s, with sensitivity of predicating CIS 66.04%,specificity 76.19%, and Youden index 0.42; when the maximum area under the curve was 0.663, EI cutoff value was 3.785 dB, withsensitivity of predicating CIS 49.06%, specificity 80.95%, and Youden index 0.30. The sensitivity was 84.91%, specificity 71.43%, andYouden index 0.56 when jointly applies the two techniques. Conclusion Both ARFI and CEUS can perform quantitative analysis of VP.The slower the SWV of the plaque and the higher the EI, the lower its stability. Therefore it can provide an objective imaging basis foridentifying high-risk groups and predicating the onset of CIS. The predictive value will see evident increase when combining the twotechniques.