Objective To investigate the efficacy of microbubble-enhanced sonothrombolysis on platelet-rich thrombi (PRT) and erythrocyte-rich thrombi (ERT) in different ages.Methods PRT and ERT in different ages were prepared both in vitro and in vivo of common carotid artery in rats.All the participants were divided into 8 groups with 4 in vitro and another 4 in vivo experiment,including PRT 3 h,PRT 24 h,ERT 3 h,ERT 24h in vitro groups and PRT 3 h,PRT 24 h,ERT 3 h,ERT 24 h in vivo groups.Microbubble-enhanced sonothrombolysis was carried out in both in vitro and in vivo experiments,and the ultrasonic images were collected.The components of PRT and ERT were identified by histopathological examination.The percentage increase of luminal cross sectional area and lytic ratio in vitro,and the recanalization rate and mean blood flow velocity of common carotid artery in vivo were mainly analyzed.Results After sonothrombolysis,both in vitro and in vivo experiment showed there was no statistically significant difference of the percentage increase of luminal cross sectional area ([121.12 ± 13.21]％ vs [130.09 ± 15.34]％),lytic ratio ([39.83± 7.09]％ vs [42.14±5.17]％),recanalization rate (83.33％ vs 91.67％) and blood flow velocity of common carotid artery ([0.21±0.02]m/s vs [0.22±0.01]m/s) between PRT 3 h group and ERT 3 h group (both P＞0.05).PRT 24 h group compared with EPR 24 h group,PRT 24 h group compared with PRT 3 h group,as well as ERT 24 h group compared with ERT 3 h group,the percent increase of luminal cross sectional area,lytic ratio,recanalization rate and blood flow velocity of common carotid artery reduced (all P＜0.05).Conclusion The efficacy of microbubble-enhanced sonothrombolysis on PRT and ERT in vitro and in vivo of of rat common carotid artery model decrease with the increase of thrombus age,especially for the PRT.