Deep vein thrombosis refers to the abnormal clotting of blood in the deep veins, and the clot (thrombus) blocks the lumen of the veins, so that the venous blood collects in the affected limbs and cannot flow back to the heart, this disease is called deep vein thrombosis, which is common in the lower limbs and is a common acute vascular disease. The causes are multifaceted, including lesions in the coagulation mechanism of the body, trauma, major surgery, hypercoagulable blood, cerebral infarction, myocardial infarction, fracture, etc. The main clinical manifestations of the affected limbs are: swelling, pain, inability to walk, superficial varicose veins, fever, and in severe cases, some of the clots can be dislodged and flow into the lungs with the blood, which can block the blood vessels in the lungs and lead to pulmonary infarction, causing chest pain, coughing, coughing up blood and other symptoms, and in severe cases, it can lead to death. Anyone who has these conditions must go to hospital immediately, preferably to a hospital specializing in vascular surgery. At present, the treatment of this disease is mainly by intravenous injection of thrombolytic drugs to dissolve the clot rapidly and restore the smooth flow of venous blood to the patient, in China, urokinase is most commonly used, and supplemented with some anticoagulant drugs such as heparin, etc. Generally, 10-14 days is a course of treatment, and the best effect is to start the medication within 72 hours after the onset of the disease, so the patient must seek medical treatment as soon as possible after the onset of the disease. In the past 20 years, the Department of Vascular Surgery of Shanghai Tongren Hospital has treated more than 1000 cases of this disease, achieving satisfactory results and accumulating rich clinical experience. Recently, some new therapies have been developed to improve the treatment effect, including venogram or Doppler ultrasound examination to clarify the site and scope of embolism and perform minimally invasive surgical thrombectomy at an early stage for those who have the conditions. A special catheter can be inserted into the thrombus through the vein, and a large amount of thrombolytic drug can be injected through the catheter to dissolve the clot directly and quickly within 1-3 days, and x-rays can be taken with the contrast agent injected through the catheter during the thrombolysis process to understand the dissolution of the clot immediately. If stenosis of the iliac vein is present during treatment, minimally invasive techniques such as balloon dilation and stent placement can be used to improve the patency of venous blood flow and prevent recurrence of thrombosis. In severe cases, the lower limb vein can be punctured and a leaky net can be placed in the inferior vena cava to stop pulmonary infarction in case the thrombus is dislodged and captured midway to the lungs to save the patient’s life.