What is ‘sclerotherapy’?
Sclerotherapy is a type of treatment that involves the injection of a special chemical into the venous malformation to ultimately shrink it and relieve the symptoms it is causing. Various substances can be used but most commonly the chemical used is Sodium Tetradecyl sulphate (Fibrovein). When injected into a lesion it causes an inflammatory reaction which leads to localised blood clots and the formation of a scar in place of the venous malformation. This corresponds to shrinkage of the malformation. This is carried out under ultrasound and x-ray control as the doctor needs to be sure that the correct part of the malformation is accessed with the needle and needs to assess the degree of communication with adjacent communicating veins.
Percutaneous ablation is also known as “sclerotherapy”. We may use these terms interchangeably when discussing the treatment of symptomatic vascular malformations.
Congenital Vascular Malformations (CVM) occur in about 1% of all births and can vary from simple, flat birthmarks to complex, 3-dimensional structures deep within the body. They can be made up of arteries, veins, lymph vessels, or a combination of these. They are usually present at birth, but are unlikely to be passed on from parent to child or for there to be more than one in any given person.
Types of Congenital Vascular Malformations (CVM)
- Arterio-Venous Malformation (AVM): Abnormal communication of arteries and veins that is associated with high blood flow. These are considered the most serious type of malformation and can occur anywhere in the body and cause pain, bleeding or strain on the heart. Fortunately, they are the rarest type of malformation.
- Venous Malformation (VM): These are the most common and often appear as dilated purple veins on the skin that are compressible. Occasionally, a VM will form blood clots and become swollen and painful. When they occur in the legs, they can also cause pain after standing or walking for long periods of time.
- Lymphatic Malformation (LM): These are also very common, and involve the ducts that carry lymph fluid from the tissues and lymph nodes back to the heart. They often occur in combination with VMs since both have a common embryological origin.
Treatment of a CVM involves the use of a needle or catheter to inject medical grade alcohol into the malformation to embolize (obstruct) the flow of blood. Embolization can be used to shrink a large CVM to make it easier to be operated on. In some cases, surgery may be avoided altogether. Sometimes the treatment requires several stages to fully eradicate the entire malformation. The specific procedure will depend on the type of CMV you have:
Transcatheter Embolization: AVMs are typically treated by inserting a catheter into the artery that leads to the malformation. Particles, glue, coils, and a variety of agents may be injected to treat an AVM.
Percutaneous Ablation: Venous and lymphatic malformations are generally treated by inserting a needle directly into the malformation and injecting medical grade alcohol or a similar agent into them to get them to shrink down and perhaps go away altogether.
- You may have pain and swelling at the treated site for up to a few days, but this is usually greatest at the start and should continue to decrease over time.
- Consult the doctor, if you have any questions or any of the following:
- Increased redness at the site of injection or catheter access.
- If you received a nerve block and numbness and/or weakness of the involved extremity persists for more than 24 hours.
- Increasing pain that is not relieved with pain medication.
- Increased swelling and/or tingling at site of treatment that does not respond to routine post-procedure care (see below).
- Skin breakdown, blister, skin with blackened areas, or decreased ability to move the treated limb.