VARICOSE VEINS

Varicose veins are abnormally enlarged veins that develop typically in the legs. Veins are responsible for returning blood to the heart from all parts of the body. Valves in the veins of the legs keep blood from falling back toward the ankles after the muscles in the calves push the blood upward. When these valves fail to work properly, blood accumulates in the veins of the lower thigh and calf, causing them to visibly enlarge and become tortuous. Spider veins, which are varicose veins of the skin, form similarly. They may be seen along with larger varicose veins, or by themselves.

Veins in the legs are considered to be either superficial or deep. The deep veins are not visible, and are surrounded by muscle and connective tissue. Superficial veins run just under the skin. Branch veins connect the superficial veins to the deep veins. Valves in the branch, or perforating veins, allow blood to run only from superficial to deep. Varicose veins can form when the valves in these perforating veins fail, allowing blood from the deep veins to over expand the superficial veins, creating visible varicosities.