基于超声剪切波技术探讨颈动脉粘弹性与其机械特性的关系

Study on the relationship between carotid viscoelasticity and its mechanical properties based on ultrasonic shear wave technique

目的应用超声剪切波频散(SWD)技术检测颈动脉粘弹性,初步探讨其对动脉机械特性的影响。方法招募无心脑血管疾病的志愿者45例,依据年龄中位数分为高年龄组(≥50岁)23例和低年龄组(<50岁)22例。应用SWD检测受试者颈总动脉粘弹性,获取颈动脉弹性模量(SWER)、粘性指标(SWDR),以及左、右侧颈动脉最大和平均环壁张应力(L-PTS、L-MTS、R-PTS、R-MTS)。比较两组上述各参数的差异;分析SWER和SWDR与L-PTS、L-MTS、R-PTS、R-MTS的相关性。结果与低年龄组比较,高年龄组颈总动脉SWER和SWDR均减小,差异均有统计学意义(均P<0.05);高年龄组中仅R-PTS较低年龄组者小,差异有统计学意义(P<0.05)。SWER与R-PTS、R-MTS、L-PTS、L-MTS均呈正相关(r=0.218、0.359、0.209、0.369,均P<0.05);SWDR与R-PTS、R-MTS、L-PTS、L-MTS不相关。结论颈总动脉环壁张应力与其弹性指标相关,而与其粘性指标不相关。

Objective To detect the carotid viscoelasticity and the relationship of mechanical properties and viscoelasticity using shear wave dispersion(SWD)technique.Methods Forty-five volunteers were recruited and divided into the older group(≥50 years old)and the younger group(<50 years old)according to the median age.The carotid arteries were examined by SWD and the indicators were obtained,including the carotid elastic modulus(SWER)and viscous index(SWDR),as well as the maximum and average tensile stress of the left and right carotid arteries(L-PTS,L-MTS,R-PTS and R-MTS).The correlations between SWER,SWDR and tensile stress were analyzed by Pearson analysis,respectively.Results In the older group,the carotid SWER and SWDR were lower than those in the younger group(both P<0.05).The R-PTS was also lower in the older group(P<0.05).SWER was positively correlated with R-PTS,R-MTS,L-PTS and L-MTS,respectively(r=0.218,0.359,0.209,0.369,all P<0.05).SWDR was not significantly correlated with R-PTS,R-MTS,L-PTS and L-MTS,respectively.Conclusion The carotid tensile stress was related to its elasticity,but not related to its viscosity.