Epilepsy brain surgery

Epilepsy brain surgery is done for any of the following reasons:

• to try to stop your seizures
• to reduce the number of seizures you have
• to make your seizures less severe.

The overall aim of epilepsy surgery is to improve your quality of life.

Who might benefit from epilepsy brain surgery

Firstly, the person’s epilepsy would need to be suitable for one of the types of brain surgery currently available (see below). Also, as taking epilepsy medicine is still the most common way epilepsy is treated, in most cases, the person would need to have tried a number of epilepsy medicines and still be having seizures.  Doctors would also want to make sure there was no other medical reason that could make epilepsy surgery a problem. And of course, they must believe that the person would have a better quality of life after surgery than before.
Epilepsy Action has more information about epilepsy, seizures and epilepsy medicine.

Types of epilepsy brain surgery

There are many different types of epilepsy brain surgery. The type you may have will depend on the type of seizures you have and where they begin in your brain. Here are some of the most commonly performed.

Resection

This is done when surgeons are sure where your seizures start in your brain. The surgery involves removing the damaged part of your brain.

Multiple subpial transection

This is carried out when it’s not possible to remove the part of the brain that’s causing the seizures. The surgeon will make a series of cuts to help separate the damaged part of the brain from the surrounding area. This stops seizures from moving from one part of the brain to other parts of the brain.

Corpus callosotomy

This surgery is done to separate the two sides (hemispheres) of the brain. It’s usually done if you have severe seizures that start in one hemisphere, and spread to the other hemisphere.

Hemispherectomy

This is major surgery, which involves removing the outer layer of one side (hemisphere) of the brain. It’s done if you have seizures because one half of your brain is damaged.

Tests before epilepsy brain surgery

If you’re being considered for surgery, it’s likely you will have lots of tests. This is called pre-surgical evaluation. The tests might include the following.

Electroencephalogram (EEG)/video-telemetry

The EEG tells the doctors about the electrical activity in the brain. During the EEG, a technician places harmless electrodes on the scalp, using a special glue or sticky tape. The electrodes are then connected to the EEG machine, which records the electrical signals in the brain on a computer. A video recording might be done at the same time. This is called video-telemetry and will be done in hospital. In this way, if you have a seizure, doctors can see exactly what happens. An EEG/video-telemetry can be done while you are awake, asleep, or both.
Epilepsy Action has more information about EEGs and video-telemetry.

Computed tomography (CT scan)

This is a type of X-ray that shows the structure of the brain. It doesn’t show if you have epilepsy. However, it might show if there is an abnormality that could cause epilepsy. CT is now an old investigation and has mostly been replaced with magnetic resonance imaging (MRI).
Magnetic resonance imaging (MRI scan)
The MRI uses radio waves and a magnetic field, rather than X-rays. Like the CT scan, it can show if there’s a structural cause for the epilepsy. The MRI is more powerful than the CT scanner, so it can pick up small or subtle abnormalities that the CT scanner can’t find.
Functional MRI scan
This is similar to having an MRI scan but, during the scan, you would be asked to do something. For example, you might be asked to tap your thumb against your fingers. Or you may be asked to look at pictures, or answer questions, on a computer screen. These activities increase the flow of oxygen-rich blood to a particular part of the brain. This type of MRI scan will help to show exactly which part of the brain manages important tasks such as thought, speech, movement, and sensation.
For more information about functional MRI scans go to the Psych Central website.
Website: psychcentral.com

Positron emission tomography (PET scan)

This scan uses a radioactive substance, called a tracer, to look for information about how the brain is working. It can also show any abnormalities.
For more information about PET scans go to NHS UK website.
Website:nhs.uk

Single-photon emission computed tomography (SPECT scan)

This scan shows different parts of the brain in different colours. You will be given an injection of a radioactive dye, which goes to your brain. The colours show how much blood flow is in each part of the brain. Usually, blood flow is higher in the part of the brain where seizures start. There are two sorts of SPECT scans. One is the inter-ictal SPECT scan, which is done between your seizures (‘inter’ means between and ‘ictal’ refers to a seizure). The other is the ictal SPECT scan, which is done just after you have had a seizure.
For more information about SPECT scans go to the GOSH website.
Website: GOSH.org.uk

Magnetoencephalography (MEG scan)

This is a new type of scan. The scanner sits outside your head and measures your brain activity. It can tell which parts of your brain are active during a certain task, and at what point in time it was active. You won’t feel any differently afterwards, and you won’t need to change your activities or rest after the scan.
For more information about MEG scans go to the Aston University website.
Website: Aston.ac.uk

Neuropsychology tests

These tests show if you have any learning problems. They involve up to eight hours of games and puzzles, split into different sessions. The tests can show whether the part of your brain that needs removing is responsible for any functions that other parts of your brain can’t take over. This is to make sure you have no problems after surgery that you didn’t have before surgery.
For more information about neuropsychology tests go to the GOSH website.
Website: GOSH.org.uk

Neuropsychiatry tests

A psychiatrist with experience of epilepsy surgery will see you as part of your initial assessment. They will see what other problems the epilepsy is causing, and decide whether epilepsy surgery may help them.
For more information about neuropsychiatry tests go to the GOSH website.
Website: GOSH.org.uk

What happens during epilepsy brain surgery

What happens during surgery depends on the type of surgery you have. Usually you will have a general anaesthetic, to put you to sleep. The surgery involves making a small opening in your skull to get to your brain. Rarely, your surgeon may wake you up during part of the operation to help the operating team locate the part of your brain that controls language and movement. Your surgeon will be able to explain this to you. After the surgery, the bone is replaced, and fixed to your skull for healing. Epilepsy brain surgery usually takes several hours.

After epilepsy brain surgery

When you wake up, your head will be swollen and painful. You will need to take painkillers for a few days. The pain and swelling will get less over the next few weeks. You will need to rest and relax in the first few weeks after epilepsy surgery, and gradually become more active. It’s usual to stay off work for around three months. Generally, you will continue to take epilepsy medicines for a year or two after surgery, but you may be able to reduce, or even stop them, after that.

Risks of having epilepsy brain surgery 

The risks depend on the type of surgery you have. The following are possible.
Memory problems
The temporal lobes handle memory and language. This means that any surgery on these parts of the brain can cause difficulties in remembering, understanding and speaking.
Seizures continuing
Cutting the connections between the two sides (hemispheres) of the brain in corpus callosotomy stops seizures spreading from one hemisphere to the other. However, it doesn’t stop all seizures, so you may still have some focal (partial) seizures.
Visual symptoms - reduced visual field or double vision
After hemispherectomy (where the outer layer of one half of the brain is removed), a person’s area of vision is often reduced or they may have double vision. This may be temporary or permanent and will depend on how much of the brain has been removed.
Partial, one-sided paralysis
After a hemispherectomy, you may have limited use of one side of your body. Physiotherapy can help with this.
Despite the tests before surgery, it’s not always possible to know exactly what the risks are. However, following the pre-surgery tests the doctors will be able to make an educated decision.
Doctors will only go ahead with surgery if the tests show that the benefits are likely to be higher than the risk of complications.
For more information about risks of epilepsy surgery, go to the Mayo Clinic website.
Website: mayoclinic.com

Seizure freedom after epilepsy brain surgery

The chances of being seizure free after surgery varies from person to person. Among other things, it depends on the type of epilepsy surgery, scan findings and whether all the information from tests fit together. The doctors involved in your care will be able to tell you more about the expected success rate of your surgery. They will also be able to tell you about any complications that could happen following your surgery.

Other types of epilepsy surgery

As well as brain surgery, there are other types of surgery that can help some people with ongoing seizures.

Vagus nerve stimulation (VNS)

Vagus nerve stimulation (VNS) uses a small generator that is implanted under the skin below the left collarbone. This is connected to a lead with two coils at one end. These coils are wrapped around the vagus nerve at the side of the neck, under the skin, during a small operation.
Epilepsy Action has more information about VNS therapy.

Deep brain stimulation (DBS)

Deep brain stimulation (DBS) is a treatment where a part of the brain is stimulated, to stop seizures. The surgery involves having a DBS system fitted. The DBS system has three parts.
1. A lead – this is a thin, insulated wire. It is placed in the part of the brain where the seizure activity happens, through a small hole in the skull.
2. An extension – this is an insulated wire that is passed under the skin of the head, neck, and shoulder. It connects the lead to the neurostimulator.
3. A neurostimulator – this is a small device, similar to a heart pacemaker. It is usually placed under the skin near the left collarbone, lower in the chest, or under the skin of the stomach.
Epilepsy Action has more information about DBS surgery.

Further information and support

If you would like to find out if surgery could help you, please contact your epilepsy nurse or specialist.
If you have already been told that surgery could help your epilepsy, your surgeon will be able to tell you more. They will also be able to answer your questions.
For more, general, information about epilepsy surgery go to the Mayo Clinic website.
Website: mayoclinic.com 
If you would like to see this information with references, visit the Advice and Information references section of our website. See Epilepsy surgery for adults.

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