The veins are injected with a solution called a sclerosant which damages the internal lining of the vein and causes blood clotting within the vein. Over a period of time your own body will destroy the vein and it will disappear. The solution used is available in different concentrations depending on the size of the vein being treated and is called Sodium Tretradecyl Sulphate or ‘STS’ for short. The procedure is performed under ultrasound guidance. Foam sclerotherapy is of particular advantage to those who have had previous varicose vein operations as it avoids going through the scar tissue of previous surgery. It is also commonly used in conjunction with EVLA. Here at the Cooden Medical Group we use foam sclerotherapy to treat superficial varicose veins and smaller to medium varicose veins by injecting sodium tetradecyl sulphate (STD) into the vein being treated under ultrasound guidance. The treatment involves creating foam, by rapidly mixing and agitating the solution with a small volume of air. This irritates or damages the lining of the blood vessel, causing it to spasm and then stick together. The blood in the vein will then clot, and blood will then re-route through healthier veins. After foam sclerotherapy, treated veins tend to fade within a few weeks, although occasionally it may take up to a month to see the full benefits. In some instances, a course of treatments may be required.