剪切波超声成像定量参数评价颈动脉斑块易损性

Study on the assessment of vulnerability of carotid atherosclerotic plaques by using shear wave elastography

目的探讨超声剪切波弹性成像(SWE)技术定量参数评估颈动脉粥样硬化斑块组成和易损性的能力。方法对126例颈动脉粥样斑块患者进行常规超声和剪切波弹性成像,常规将其分为均质斑块组和不均质斑块组,应用SWE弹性模量参数来定量评价不同类型斑块的杨氏模量值及其分布特征,比较不同类型颈动脉斑块及斑块内部低无回声区的超声弹性特征。结果 126例患者中,颈动脉常规超声共检出193个斑块,其中均质斑块136个,不均质斑块57个。剪切波超声弹性图像显示均质斑块为较均匀分布的蓝绿色,不均质斑块弹性图像颜色混杂呈红蓝相间。不均质斑块组整体斑块的平均、最小及最大杨氏模量值均明显低于均质斑块组(P均<0.05),不均质斑块组整体斑块的杨氏模量SD值高于均质斑块组(P<0.05)。均质斑块组和不均质斑块组的的斑块内低无回声区的平均、最小、最大弹性模量值均低于整体斑块(P均<0.05)。结论应用超声剪切波弹性成像技术能观察到斑块脂质核心的弹性特征,有助于识别颈动脉易损斑块。

Objective To evaluate the ability of shear wave elastography（ SWE） in the characterization of composition and vulnerability of carotid plaques. Methods One hundred and twenty- six patients with atherosclerotic plaques in common carotid arteries underwent SWE and routine ultrasound. Plaques were divided into homogeneous plaque group and heterogeneous plaque group with the applications of SWE elastic modulus parameter in order to quantitatively evaluate the magnitude of different types of plaques and distribution of the Young＇s modulus,and comparing elastic parameters of different types of plaques in carotid artery and sonolucent areas. Results One hundred and ninety- six carotid plaques were detected by conventional ultrasound,among them 136 were homogeneous plaques,and 57 belonged to heterogeneous plaques. Shear wave ultrasonic elasticity image showed a homogeneous plaque as uniform blue- green color,and the elasticity image of heterogeneous plaque mixed with red and blue colors. The average,minimum and maximum values of Young＇s modulus in heterogeneous plaque group were significantly lower than those of homogeneous plaque group（ P〈0. 05）,the Young＇s modulus of SD values of homogeneous plaques were higher than those of heterogeneous plaques group（ P〈0. 05）. The minimum and maximum elastic modulus of sonolucent areas within plaques were lower than the overall plaques（ P〈0. 05）. Conclusion SWE can detect the presence of a lipid core. Studies on elastic parameters of plaques with SWE are required to identify vulnerable plaques.