The main task in the treatment of varicose veins of the lower extremities is to stop the blood flow in the severely refluxing superficial veins of the lower extremities, usually including the great saphenous vein and its dependent branches, the small saphenous vein and its dependent, or the penetrating veins. Classically, varicose vein stripping is performed by removing the diseased vein and completing the task of stopping blood flow. Multiple incisions are usually made in the groin, ankle and lower leg to complete the procedure. The most traumatic route is the saphenous vein stripping, which runs medially through the lower extremity and is more invasive. Minimally invasive radiofrequency closure aims to achieve the same surgical goal as the traditional procedure, namely to stop the return of blood in the diseased vein. However, a gentler approach is used in terms of treatment idea, i.e., instead of removing the diseased vein, the diseased vein is closed in situ and the reflux stops naturally as the lumen of the vein is closed. In the principle of treatment, this closing process is accomplished by heat conduction. The endothelium and the entire vessel wall rapidly contract under the effect of heat and after a certain time the entire vein becomes completely fibrotic and the lumen disappears permanently. The key component of this heat transfer is the radiofrequency treatment catheter. Its length completely covers the entire length of the saphenous vein and its outer diameter is very slim, less than 2 mm. Therefore, the introduction process requires only about 2 mm of trauma to complete. Once the catheter is introduced, the target vein can be treated in segments through the catheter. Each segment is reliably treated for a length of approximately 6-6.5 cm, and the multiple treatment segments ensure reliable closure of the vein lumen and reduce the incidence of thermal damage to the surrounding tissue. Typically, this treatment procedure takes only about 15 minutes to complete. The procedure of radiofrequency catheter vein closure is not complicated, but its therapeutic effect depends not only on the catheter, but more importantly, a comprehensive lower limb venous ultrasound examination must be performed before the procedure to clarify the diseased target vein, the obvious target vein patency, its direction of travel, and the presence of variants to reduce the blindness of the treatment. Before closure, effective swelling anesthesia (local anesthesia) is also performed to ensure painless operation and reduce thermal damage to surrounding tissues. In addition, during the operation, it must be performed strictly under ultrasound guidance to ensure that the catheter placement is reliable; to ensure the correct level of swelling anesthesia and the assurance of the surrounding tissues is in place; and to evaluate the closure effect immediately after the closure.