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Foam sclerotherapy for varicose veins

prof. Usman Jafferprof. Usman Jaffer

What is it?

Small surface veins, and some thread veins in the skin can be treated by injection of a small quantity of a medical preparation of an ‘anionic surfactant’ (essentially a ‘soap’ like agent) called sodium tetradecyl sulfate (STS). STS is mixed with air to form micro-bubbles before injection, giving it a large surface area, and meaning more of your veins can be treated with less of the ‘sclerosing agent’, which is then carefully injected into the target vein under ultrasound guidance. 

The SDS foam works, like soap, by dissolving some of the fat in the cells lining the vein, which leads to them becoming irritated. Thrombus (‘blood clot’) then forms within the targeted vein, and as this resolves the vein hardens and closes. Foam is not suitable for large veins, and even small veins may need several courses of treatment to obtain a satisfactory result. The veins can feel hard initially after treatment, and some - particularly those with very pale skin - may find that they are left with skin marking after the procedure.

Why is it done?

Sclerotherapy is a minimally invasive procedure designed to block off refluxing vein in the leg. It can also be done to improve the appearance of your varicose veins. 

Will I need to do any preparation?

No preparation is required.



No anaesthesia is required.

What does it involve?

Foam sclerosant is formed by mixing chemical with air. The 'Tessari' methods is commonly used. The foam created is then injected directly to the vein to be treated under ultrasound guidance. The foam solution causes intense spasm of the vein, damages the internal lining of the vein and causes blood clotting within the vein.

Step of Foam sclerotherapy: 1. The vein being targeted is identified with ultrasound, 2. Foam is generated and injected directly in the vein, 3. The vein goes into spasm and closes. 

After injection you will be asked to move your ankle up and down few times in order to spread it from the site of injection and 'flush' is out of the deep veins to avoid Deep Vein Thrombosis (DVT).

The progress of foam spreading within the vein is apparent on the ultrasound.

An injection of blood thinner (heparin) may be given at the end of the procedure to reduce the risk of Deep Vein Thrombosis.

Post procedure course (follow-up)

The leg is either bandaged or a compression stocking is applied. This is in order to compress the veins and support them while they are scarring closed.

How long will I stay in hospital?

No stay is required, done as an outpatient procedure. Sometimes can be done as part of another operation which is treating the Saphenous veins.

What care will I need at home?

It is important to mobilise regularly during the waking hours to maintain regular flow in the deep veins. This is to prevent stagnation of the blood flow which may result in clotting or thrombosis (DVT).

Will I need someone to stay with me?


Will I need any special equipment when I go home?


What follow up care is needed? 

Clinic follow up may be useful in 2-6 weeks to evaluate improvement. If symptoms of thrombophlebitis occur then you may need to be seen earlier.

When can I start my normal activities again (e.g. driving, sports or work?)

Immediately or the next day, comfort allowing.

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prof. Usman Jafferprof. Usman Jaffer

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