Objective:To explore the assessment value of ultrasound images for the curative effect of placed umbrella-shaped filters in treating deep vein thrombosis in the lower limbs.Methods:A retrospective analysis was conducted on the clinical data of 85 patients with deep vein thrombosis of the lower extremities who admitted to Peking University Third Hospital Yanqing Hospital from October 2018 to October 2022.Based on the treatment effect and the improvement of clinical symptoms,the patients were divided into a cure group(38 cases),a significant effect group(27 cases)and an effective group(20 cases).All patients underwent the placement of an umbrella-shape filter and popliteal vein puncture on the affected side,and the urokinase was pumped into the body after a thrombolytic catheter was connected to micro pump.All patients underwent contrast-enhanced ultrasound examination,and the diluted ultrasound contrast agent was injected through a thrombolytic catheter on the 1st,3rd and 5th day after surgery,so as to analyze the perfusion situation of ultrasound contrast.Time intensity curve(TIC),time to peak(TTP),density peak intensity(DPI)and ascending branch slope(C)of the curve were obtained by using ultrasound contrast quantitative analysis software.And then,the quantitative parameters of patients among the 1st,3rd and 5th day after surgery were compared.Results:Compared with these before treatment,the reduction of the intima of the wall(82 cases),the better vascular compression(58 cases)and the clear echo in the lumen(61 cases)were significantly improved after treatment,and the differences were statistically significant(x2=52.407,61.917,74.518,P<0.05),respectively.The total effective rate was 100%.The TTP,DPI and C of the cure group,the significant effect group and the effective group were respectively(14.02±5.41)s,(-10.77±3.22)s and(4.91±1.33)dB/s on the 5th day after surgery.The TTP,DPI and C of the significant effect group[(17.95±7.41)s,(-13.87±4.01)s and(4.11±1.20)dB/s]on the 5th d after surgery were significantly different from those on the 1st day after surgery(cure group:t=11.615,-22.122,-16.112,P＜0.001,significant effect group:t=8.820,-13.073,-10.804,P＜0.001,effective group:t=6.791,-7.725,-6.633,P＜0.05),respectively.The DPI and C of the three groups on the 3rd day after surgery were significantly higher than those on the 1st d after surgery,while the TTP was significantly lower than that on the 1st day after surgery,and the differences were statistically significant(cure group:t=-18.857,-12.387,-7.254,-7.435,P＜0.001,effective group:t=-5.076,-6.919,P＜0.05),respectively.The DPI and C on the 5th d after surgery in the cure group and the significant effect group were significantly higher than those in the effective group(tDPI=12.219,7.457,tC=4.826,2.530,P＜0.05),respectively.Conclusion:The deep vein thrombosis of the lower extremities can choose the method of thrombolysis treatment after the umbrella-shape filter is placed,which can effectively intercept the thrombosis and can be indwelled in the vein in a long time,and which can also observe perfusion during inferior vena cava contrast,and which can also intuitive appear the recanalization of the veins after umbrella-shape filter is placed in patients with deep vein thrombosis of the lower extremities after the treatment of catheter thrombolysis.