超声剪切波频散成像评估颈动脉黏弹性的初步研究

Assessment of elasticity and viscosity in the human carotid artery using ultrasound shear wave dispersion imaging: a comparison study

目的应用超声剪切波频散成像(shear wave dispersion,SWD)技术检测志愿者颈动脉黏弹性,初步探讨其可行性及其影响因素。方法招募无心脑血管疾病的志愿者45例,依据年龄分为高年龄组(≥50岁)和低年龄组(<50岁)。采用SWD技术检测受试者颈动脉,获取收缩期颈动脉轴向弹性模量(SWER)和黏性指标(SWDR)。并获取颈动脉环向弹性参数脉搏波速度(PWV)作为参考指标。比较不同年龄组志愿者SWER、SWDR和PWV的差异;采用Pearson相关分析分析SWER和SWDR与PWV的相关性。结果①与低年龄组比较,高年龄组颈动脉PWV增高,SWER和SWDR均减小(均P<0.05)。②颈动脉SWER与PWV呈负相关(r=-0.256,P<0.05)。在高年龄组中,SWER与收缩压呈负相关(r=-0.357,P<0.05),SWDR与PWV呈负相关(r=-0.393,P<0.05);在低年龄组中,SWDR与收缩压呈正相关(r=0.366,P<0.05)。结论低年龄人群颈动脉黏性特征较高年龄人群明显,增高的黏性指标与PWV有关。SWD技术可评估颈动脉黏弹性,有助于进一步认识其组织特性。

Objective To detect the viscoelasticity of carotid artery in healthy volunteers using ultrasonic shear wave dispersion (SWD) technique, and explore the feasibility and influencing factors for SWD parameters. Methods Forty-five healthy volunteers were recruited and divided into elder group (≥50 years old) and younger group (<50 years old) according to the age. The carotid arteries were examined by SWD at systole, axial elastic modulus (SWER) and viscous index (SWDR) were obtained. The pulse wave velocity (PWV), a carotid artery circumferential elastic parameter was obtained and considered as the reference indicator. The difference of SWER, SWDR and PWV were compared between two groups;and the correlation between them were analyzed by Pearson analysis, respectively. Results ①Compared with the younger group, the carotid PWV increased, while SWER and SWDR decreased in the elder group(all P<0.05).②In all subjects, SWER was negatively correlated with PWV (r=-0.256, P<0.05). In the elder group, SWER was negatively correlated with systolic blood pressure (r=-0.357, P<0.05), and SWDR was negatively correlated with PWV (r=-0.393, P<0.05). In the younger group, SWDR was positively correlated with systolic blood pressure (r=0.366, P<0.05). Conclusions Compared with the elder group, the carotid viscoelasticity was higher in young people, and it is correlated with PWV. SWD can evaluate carotid viscoelasticity, and contribute to better understanding of its tissue characteristics.