Venous ulcers, also known as stasis ulcers or ulceration, are wounds that are thought to occur due to increased venous pressure in the leg when venous valves do not function properly. They usually develop on the inside of the leg above the ankle and are long lasting sores that takes more than 4 to 6 weeks to heal. Ulcerations or chronic non-healing wounds of the lower leg, ankle, or foot are most commonly caused by chronic venous insufficiency and are frequently associated with varicose veins. Usually, red or brown skin changes appear on the leg that then progress to an open wound. Sometimes a minor injury to the leg leads to an opening in the skin which does not heal. Other causes of ulceration of the lower extremity, such as diabetic foot ulcer, arteriosclerotic occlusions of arterial blood flow, and infection, must be considered before treatment is initiated.

A venous stasis causes abnormal reverse flow in the veins and blood pooling in the leg. The increased pressure results in blood leak from the veins that in turn damage the surrounding tissues. The skin around the ulcer may appear swollen, tight with reddish-brown skin discoloration. The pain associated with a venous stasis ulcer varies and can be a burning or aching sensation along with swelling, fullness or heaviness in the leg. Over time the small wound may become much larger and deeper while the skin swollen and crusted in appearance. With the disease progression the affected area can thicken and harden and it may feel warm or hot. Venous ulcers are painful and difficult to heal using usual wound care measures. Leg compression with elastic stockings along with leg elevation and intensive wound care may be successful in achieving healing, but frequently the ulcer recurs. With the use of ultrasound for accurate diagnosis of the source of the high venous pressure and minimally invasive venous ablation procedures, vein surgeons are now able to cure most of chronic venous ulcers reducing high recurrence rate.