Chronic lower extremity ulcers (old rotten legs) are difficult to treat, and these ulcers do not heal for a long time or recur after healing, seriously affecting the normal life and work of patients. Some of them may even become “cancerous” or “amputated”. Among these ulcers, venous diseases cause more than 90% of the ulcers. Venous ulcers mainly include primary lower extremity superficial venous valve insufficiency (saphenous varicose vein), primary lower extremity deep venous valve insufficiency, deep and superficial traffic branch venous valve insufficiency, and lower extremity deep venous thrombosis syndrome. Ulcers are usually found on the inner or outer side of the lower third of the lower leg, with the inner side being more common, and are often accompanied by swelling and pigmentation of the surrounding tissue. The area is often itchy at first, then painful, red and erosive, and slowly turns into an ulcer. The ulcers vary in size and are whitish or dark red. The edges of the ulcers become thickened and elevated over time, and the surrounding skin becomes darker. It is now believed that the mechanism for the formation of these ulcers is venous hypertension in the lower extremities caused by venous valve insufficiency, which in turn causes fibrin deposition around the subcutaneous capillaries, forming a diffusion barrier for oxygen and other nutrients; at the same time, the reduced fibrinolytic activity of the blood also makes the ability to remove fibrin diminished. Under the combined effect of the two, the nutritional status of the skin deteriorates and eventually ulcers are formed. Therefore, it is important to address the hypertension in the veins of the lower extremities. With the development of vascular surgery, physicians have come to realize that many lower extremity venous valve malfunctions are due to stenosis in the proximal vessels. It is essential to identify stenoses in the iliac or inferior vena cava by imaging or CTV (CT vena cava imaging). After exclusion of vena cava or iliac vein stenosis, healing of the ulcer is possible by implantation, ligation of superficial veins around the ulcer and traffic branch veins, high saphenous vein ligation with varicose vein resection, and deep vein valve reconstruction. Repeated ulceration of the wound and imaging showed stenosis at the entrance of the inferior vena cava.