What is foam sclerotherapy?

A sclerosant is a medication that irritates the lining of a vein, causing the walls to stick together so the vein closes. Mixing the medication into a foam allows it to push blood out of the way and remain in contact with the vein wall, which makes it effective in larger veins. Over the following weeks and months, the closed vein is absorbed by the body.

Ultrasound is used throughout so that your consultant can see the vein and guide the foam precisely to where it is needed.

Who is suitable?

Foam sclerotherapy may be recommended on its own or alongside other treatments. It is particularly useful for:

  • Smaller or twisted varicose veins that are not suitable for laser treatment.
  • Veins that remain after EVLA or phlebectomy.
  • Varicose veins that have returned following previous surgery.
  • Patients for whom a quick treatment with no incisions is preferred.

It is not usually carried out during pregnancy, and may not be suitable for patients with a history of blood clots or certain heart conditions. Your consultant will assess your suitability at consultation.

At a glance

Procedure time: 20 to 30 minutes. Anaesthetic: None usually required. Hospital stay: Walk in, walk out. Time off work: Usually none, or the rest of the day. Compression stockings: As advised by your consultant. Sessions: One or more, depending on the veins treated.

How does foam sclerotherapy work?

  • You lie comfortably on a couch and the vein is located using ultrasound.
  • A fine needle is placed into the vein and the foam is injected in small amounts. You may feel a slight sting.
  • Your consultant watches the foam on the ultrasound screen as it fills the vein.
  • Your leg is kept still and raised for a few minutes while the foam takes effect.
  • A compression stocking or bandage is applied before you stand, and you are then asked to walk for a short time before going home.

Aftercare and recovery

You can return to most normal activities the same day, and regular walking is encouraged. You will be asked to wear compression on the treated leg, and your consultant will advise how long this is needed.

It is common for the treated vein to feel firm, lumpy or tender for a few weeks as it closes. Some brown discolouration of the skin over the vein can also appear. This usually fades over several months. Some patients need more than one session, typically a number of weeks apart, to achieve the best result.

Risks

Foam sclerotherapy is a safe treatment and serious complications are uncommon. Risks include tender lumps along the treated vein, inflammation of the vein (phlebitis), brown discolouration of the skin, and the appearance of fine red thread veins near the treated area. Rarely, patients experience a brief visual disturbance, headache or chest tightness shortly after treatment, which usually settles within minutes. Uncommon or rare risks include a blood clot in the deep veins of the leg (deep vein thrombosis), a small skin ulcer at the injection site, and allergic reaction. Your consultant will discuss all risks with you at consultation.

Frequently asked questions

Is foam sclerotherapy painful?

Most patients feel only a small scratch from the needle and a mild stinging or aching as the foam is injected. An anaesthetic is not usually needed.

How many treatments will I need?

This depends on the number and size of the veins being treated. Some patients need only one session, while others need two or three. Your consultant will give you an estimate at consultation.

How soon will I see results?

The vein closes at the time of treatment, but it takes time for the body to absorb it. Veins usually become less visible over several weeks, with the final result seen after a few months.

Is the foam safe?

Yes. The medication used has been used to treat veins for many years. Only small amounts are injected, and the foam is quickly broken down by the body.

How is foam sclerotherapy different from EVLA?

EVLA uses laser heat to close the main underlying vein and requires local anaesthetic along its length. Foam sclerotherapy uses medication, requires no incisions, and is well suited to smaller, twisted or recurrent veins. The two are often used together.

Can the veins come back?

A vein that has been successfully closed does not usually reopen, although this can occasionally happen and can be treated again. New varicose veins can also develop over time.

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