Varicose veins in the lower extremities are a common and frequent disease, the incidence of which can be more than 10% in the population, referring to the tortuous dilatation of the main trunk and branches of the saphenous (or small saphenous) veins, which can lead to edema, hyperpigmentation, affect the beauty of the lower extremities, and even ulceration and infection. The traditional treatment method is ligation and stripping, which is effective; however, it has many incisions and affects the aesthetics; at the same time, it may bring postoperative pain and abnormal sensation. The specific method of transcatheter foam sclerotherapy is to puncture through the femoral vein, deliver a 1.33mm diameter catheter to reach the main trunk of the varicose vein and inject sclerosing agent to produce aseptic inflammation of the vessel, which leads to adhesions and occlusion, and ultimately to the disappearance of the varicose vein. This method has been approved at the European Foam Sclerotherapy Coordination Meeting (1st and 2nd) in 2003 and 2006, and is considered an effective method for the treatment of varicose veins, which is promoted and applied worldwide. Its advantages include: 1.Minimally invasive: there is only a puncture point at the root of the thigh, no incision, beautiful; 2.Good effect: it not only solves the existing varicose veins, but also eliminates the hidden danger of saphenous vein reflux, and also deals with the traffic branch, which reduces the risk of recurrence; 3.Fast recovery: the patient can go down to the ground 24 hours after the operation, no need to remove stitches, less pain; 4.Short hospitalization cycle: generally 1-2 days can be observed after the operation Discharge from the hospital, and regular outpatient review later; 5, less complications, etc.