ObjectiveTo investigate the haemostatic effect of combining pulsed therapeutic ultrasound (TUS) and microbubble (MB) on splenic trauma.MethodsForteen healthy dogs were divided into 3 groups.Six animals were treated by microbubble-enhanced therapeutic ultrasound (MEUS),the other eight animals were treated with TUS only ( n =4) and the MB only ( n =4) served aS the controls.The spleens of all animals were surgically exposed and a 20 mm long,5 mm deep incision was created on the spleens using scalpel.Human prothrombin complex (HPC) was slowly injected prior to the treatment.During the procedure,the initial bleeding rate and the bleeding rate after the treatment were calculated using gauze weighing.Contrast enhanced ultrasound (CEUS) was performed to assess the blocking effects of splenic circulation.The targeted spleens were harvested for pathological examination.ResultsThere were no differences in initial bleeding rate before treatment.After treatment,in the MEUS group oozed blood was found and the bleeding rate were lower than that of the TUS and the MB groups ( P ＜0.05).A nonenhanced or perfusion defect region was formed within the treated area.The histological results showed splenic sinus hyperemia,platelet aggregation and intravascular thrombosis.Conclusions Microbubbles enhanced pulsed therapeutic ultrasound can arrest the regional blood circulation of spleen by disrupting the microvasculature and this can be used in splenic heamostasis for treating spleen trauma.