Also known as varicosities, varicose veins are abnormally widened veins that are swollen, dark and frequently twisted or contorted instead of straight. Varicose veins may occur anywhere but they usually occur in the legs and feet. They may cause swelling (edema), inflammation and a dark color around the ankles.

For some people, the only problem caused by varicose veins is their appearance. For most people, however, varicose veins can cause pain, throbbing or itching. In extreme cases, varicose veins can lead to the development of a leg ulcer
(sore). A leg ulcer demands immediate medical attention to avoid serious medical consequences, such as amputation of the affected limb. Varicose veins also may be a sign of a higher risk of other medical problems in the circulatory system, such as vascular disease.

Varicose veins are more common in women than men. The condition appears in about half of all adults age 50 and older. The cause is uncertain, but the greatest risk factor is heredity (being born with weak vein valves), according to the U.S. National Institutes of Health (NIH).

Varicose veins can be treated with a variety of approaches, including surgical intervention, injection therapy and catheter-based therapies.