Acute lower extremity deep vein thrombosis has become a common condition. One of the biggest advances in vascular surgery in recent years has been the placement of thrombolysis for acute lower extremity DVT. Traditional treatment of lower extremity DVT is based on anticoagulation, which can prevent the spread of thrombus and thrombus dislodgement causing pulmonary embolism, but it has no effect on the formed thrombus, and the deep veins of lower extremity are still blocked by thrombus, which may lead to sequelae of DVT and recurrence of thrombus in the future and seriously affect the quality of life. In addition, the previous thrombolytic treatment by infusion of thrombolytic drugs through peripheral vascular route or arterial route has been proved to be ineffective, but the only way to dissolve the formed thrombus and restore the open deep vein is to implant a thrombolytic catheter into the thrombus and inject thrombolytic drugs, which can avoid the sequelae of deep vein thrombosis and the possibility of recurrence of thrombosis. The efficacy of this procedure has been recognized abroad and is gradually written into clinical guidelines. Indications for cannulation thrombolysis 1.Thrombosis in iliac vein and femoral vein; 2.Thrombosis within 2 weeks. All steps can be completed through the eye of a needle. 1.Ultrasound-guided puncture of the affected N vein and implantation of a thrombolytic catheter; 2.Implantation of a vena cava filter; 3.Continuous infusion of urokinase, rTPA and other thrombolytic drugs through the thrombolytic catheter, and daily review of thrombus dissolution, usually lasting 1-3 days. If there is iliac vein compression, a stent can be implanted, and the thrombolytic catheter will be removed after complete dissolution of the thrombus; 4. The vena cava filter will be retrieved after 3-5 days. Postoperative patients are treated with anticoagulation and elastic stockings for six months, and anticoagulants and elastic stockings can be completely discontinued, and the veins of the lower extremities are reviewed annually afterwards for ultrasound. When the weather turns cold, the blood flow in the body slows down, which is the peak time for the occurrence of deep vein thrombosis in the lower extremities. In my clinic, I often meet patients who have formed DVT for months or years and want to seek a better solution to treat the thrombus completely, but with the current medical level, there is really nothing we can do, because the thrombus cannot be removed when it becomes hardened by mechanization after a little time. Therefore, time is the key to treatment, and any thrombus formed within 2 weeks or even a little longer can be completely cured by placement of thrombolysis.