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 . T he carotid arteries were examined by SWD at systole ,axial elastic modulus ( SWER ) and viscous index ( SWDR ) were obtained . T he pulse wave velocity ( PWV ) ,a carotid artery circumferential elastic parameter was obtained and considered as the reference indicator . T he difference of SWE R ,SWDR and PWV were compared between two groups ; and the correlation between them were analyzed by Pearson analysis ,respectively . Results ① Compared with the younger group ,the carotid PWV increased ,w hile SWE R 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 .

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 (SWE_R) and viscous index (SWD_R) were obtained. The pulse wave velocity (PWV), a carotid artery circumferential elastic parameter was obtained and considered as the reference indicator. The difference of SWE_R, SWD_R 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 SWE_R and SWD_R decreased in the elder group(all P<0.05). ②In all subjects, SWE_R was negatively correlated with PWV (r=-0.256, P<0.05). In the elder group, SWE_R was negatively correlated with systolic blood pressure (r=-0.357, P<0.05), and SWD_R was negatively correlated with PWV (r=-0.393, P<0.05). In the younger group, SWD_R 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.