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Sturge-Weber syndrome

What is a syndrome?

A syndrome is a group of signs and symptoms that, added together, suggest a particular medical condition. In epilepsy, examples of these signs and symptoms would be things like the age at which seizures begin, the type of seizures, whether the child is male or female and whether they have physical or learning disabilities, or both. The results of an electroencephalogram (EEG) are also used to help identify epilepsy syndromes.

Epilepsy Action has more information about seizure types, learning disabilities, and the EEG.

If you would like to know more about an epilepsy syndrome, please speak to your doctor. If you would like to know more about epilepsy in general, please contact Epilepsy Action.

Sturge-Weber syndrome (SWS)

Sturge-Weber syndrome (SWS) is a rare condition, in which the presence of a birthmark (called a ‘port wine’ stain), usually on one side of the face, is associated with an abnormality of the brain. This is caused by abnormal blood vessels on the surface of the brain. This abnormality usually results in epileptic seizures and other problems.

SWS is usually a spasmodic occurrence - in other words it does not run in families. It is very, very rare for two children in the same family to have SWS.

Epilepsy Action has more information about seizure types.


The first abnormality noted in SWS is the birth mark. This is flat and deep red. It is due to abnormalities of the very small blood vessels in the skin. The medical word for this abnormality is ‘angioma’. The most common site for the birth mark is the forehead on one side of the face, often coming down on to the cheek, nose or upper lip. Rarely, both sides of the face are involved and, on occasions, similar birth marks are present on other parts of the body. Even more rarely, the birth mark may not be visible.

Seizures develop in over two thirds of all children with SWS. They may start at birth or in the first year of life. They are usually focal (also called partial) motor seizures involving jerks of one side of the body only. The seizures may become generalised and evolve into other types of seizures, such as drop attacks, myoclonic seizures or infantile spasms. The seizures are often very frequent and prolonged seizures may occur. This may result in status epilepticus. The status may be a focal or generalised. Status epilepticus is a seizure that lasts 30 minutes or longer, or a series of seizures without consciousness being regained in between. Status epilepticus needs urgent medical attention.

Epilepsy Action has more information about seizures and status epilepticus.

After frequent or prolonged seizures, a weakness in one side of the body (hemiparesis or hemiplegia) frequently develops. The severity of weakness is closely related to the frequency and severity of the seizures.

The seizures may be resistant to drug treatment. As the child grows the weakness may become more severe and permanent. Often, abnormalities of vision develop, with an inability to see on the same side as the weakness (hemianopia).

The abnormal blood vessels may involve the eye and result in an abnormality of the drainage of fluid within the eye. This results in raised pressure in the eye (glaucoma). This may be present at birth and may cause visual impairment if not treated.

Learning disabilities are present in up to two out of three children with SWS. In some children, severe learning disabilities develop. The more frequent and the more severe the seizures, the greater is the severity of the learning disabilities.

Epilepsy Action has more information about learning disabilities.


The cause of this syndrome is unknown. It is a type of abnormal development of the blood vessels over part of the brain. This happens during pregnancy, probably quite early on.

The abnormal blood vessels are usually over the back part of the brain (the occipital lobe). They may also be in other regions of the brain and, rarely, on both sides of the brain.

The blood vessel abnormality leads to abnormal functioning of the brain in the same region, which is the cause of the epilepsy. As the child grows, the brain on the affected side may become shrunken (atrophy). Deposits of calcium occur in the abnormal vessels and underlying brain. This may show up on a skull X-ray or CT brain scan.

Epilepsy Action has more information about brain scans used for diagnosing epilepsy.


Treatment is mainly directed towards trying to control the frequent seizures. This is because the outcome depends very much on controlling the seizures. This may be possible with epilepsy medicines. However, in many cases the epilepsy is resistant to treatment. In these cases, early consideration is given to surgery. The surgery involves removing or disconnecting part of the brain in the region of the abnormal blood vessels. This is called a hemispherectomy or hemispherotomy.

The outcome from surgery may be excellent. Treatment of glaucoma, if it develops, is possible and laser treatment may be very effective for the birth marks.

Information about treatments for children can be found on the Medicines for Children website.

There may be research studies open that are relevant to this epilepsy syndrome. Your child’s doctor will be able to discuss this with you.

If your child has this syndrome they may have prolonged or repeated seizures. Your child’s doctor will discuss a ‘rescue’ or emergency care plan with you to treat any prolonged or repeated seizures.


The outlook depends on the extent to which the brain is affected. This seems to be closely linked with the frequency and the severity of the seizures.

If the seizures are frequent, prolonged and difficult to control then the learning disabilities, hemiplegia and visual problems are more severe. If the seizures are controlled, then a much better (but not necessarily normal) outlook can be expected.

If the abnormality is present on both sides of the brain the outcome is usually poor because the seizures are more severe and the learning disabilities are greater. In addition, it is less likely that surgery (hemispherectomy or hemispherotomy) will cure the epilepsy.


Contact a Family
209-211 City Road
London EC1V 1JN
Phone: 0808 808 3555
Website: www.cafamily.org.uk

Sturge-Weber Foundation (UK)
348 Pinhoe Road
Exeter EX4 8AF
Phone: 01392 464 675
Website: www.sturgeweber.org.uk 

HemiHelp is a charity providing support and information to people with hemiplegia and their families in the UK.
Website: hemihelp.org.uk 


Our thanks

Epilepsy Action would like to thank
• Dr Richard Appleton, and Dr Rachel Kneen, consultant paediatric neurologists at Alder Hey Children’s Hospital, Liverpool, UK and
• Dr Stewart Macleod, consultant paediatric neurologist at Royal Hospital for Sick Children, Glasgow, UK.
They have kindly prepared the information on this page. It is based on their own research, experience and expertise.

This information is exempt under the terms of The Information Standard.

  • Updated December 2012
    To be reviewed December 2015

Comments: read the 1 comments or add yours


On reading this it answered some questions about granddaughters condition sws, as I don't remember ever being informed or advised by anyone or any support groups or pages about the affected side of brain shrinking......this is the only site I have read about this.
It was also very easy to read and understand, thank you and well done

Submitted by Jeanette Tinsley on