Varicose veins are veins that have become enlarged and twisted. The term commonly refers to the veins on the leg, although varicose veins can occur elsewhere.Veins have pairs of leaflet valves to prevent blood from flowing backwards (retrograde flow or venous reflux).Leg muscles pump the veins to return blood to the heart, against the effect of gravity. When veins become varicose, the leaflets of the valves no longer meet properly, and the valves do not work. This allows blood to flow backwards and the veins to enlarge even more. Varicose veins are most common in the superficial veins of the legs, subject to high pressure when standing. Besides being a cosmetic problem, varicose veins can be painful, especially when standing. Severe long-standing varicose veins can lead to leg swelling, venous eczema, skin thickening (lipodermatosclerosis) and ulceration.
Non-surgical treatments include sclerotherapy, elastic stockings, leg elevation and exercise. The traditional surgical treatment has been vein stripping to remove the affected veins. Newer, less invasive treatments which seal the main leaking vein are available. Alternative techniques, such as ultrasound-guided foam sclerotherapy, radiofrequency ablation and endovenous laser treatment, are available as well. Because most of the blood in the legs is returned by the deep veins, the superficial veins, which return only about 10% of the total blood of the legs, can usually be removed or ablated without serious harm.Secondary varicose veins are those developing as collateral pathways, typically after stenosis or occlusion of the deep veins, a common sequel of extensive deep venous thrombosis (DVT). Treatment options are usually support stockings, occasionally sclerotherapy and, rarely, limited surgery.
Varicose veins are distinguished from reticular veins (blue veins) and spider veins, which also involve valvular insufficiency,by the size and location of the veins.