Epilepsy surgery explained

Approximately 70% of people with epilepsy find their seizures can be controlled with medication. It is usual for a person with epilepsy to have tried at least two anticonvulsant medications at suitable doses, before it is considered that medication may not be completely effective for seizure control.

For this group of people, it may be worth considering epilepsy surgery.

Deciding to have surgery for epilepsy is a big decision. The assessment process can take more than a year, and treatment (in most cases) will involve major brain surgery.

Resective surgery

There are various causes of epilepsy, and for many people, the cause is unknown. Some people however, have a structural abnormality in part of their brain, which could be the cause. This could be something they were born with, such as scarring, or an area that did not develop properly. Alternatively, it could have developed in later life. As part of the assessment process, you will have a scan to see if the abnormal epileptic activity in the brain that occurrs during a seizure starts in the same area as the abnormality. Resective surgery would involve removing this part of the brain.

You could be considered for resective surgery if

  • you've tried several anti-epileptic drugs but they have been unsuccessful or unsuitable
  • your seizures arise from one localised area of the brain
  • your ability to function normally would not be affected by operating on this area of the brain, and the surgeon can get to this area without causing further damage to any other parts of the brain
  • you have a good chance of becoming seizure free after surgery
  • you do not have any other medical problems that would make you unsuitable for surgery.

Benefits of resective surgery

Resective epilepsy surgery aims to improve quality of life for patients and their families. Around 70% of people who have resective epilepsy surgery become seizure free. A further 20 to 25% of people find their seizures are greatly reduced. A small number of people will not benefit. Our complex assessment process gains as much information as possible about the chance of success, and identifies specific risks to each individual. 

Risks of resective surgery

Any major operation requiring an anaesthetic carries risks. There are many different types of epilepsy surgery, and as everyone is different, until the tests are completed we cannot be specific about what the risks are to each patient. The most common type of operation is on the temporal lobe of the brain. In general, the risk of death is less than 1%. There may be a persisting neurological deficit in up to 2 to 3% of people, such as weakness in the opposite side of the body to the surgery. With this type of operation there may be a small loss of vision in the upper outer corner, again on the opposite side. This is not usually noticeable but may affect your ability to drive. There can also be deterioration in memory. All of these risks are discussed in greater detail in our booklet on epilepsy surgery. Please contact us if you would like a copy.

Functional procedures

If the area is not removable, it may be possible to affect the way a part of the brain works without removing any brain tissue. Vagal nerve stimulation is an example of this type of surgery.

Alternatives to surgery

If surgery is not suitable, your condition will continue to be managed by medication. The consultant neurologist in the epilepsy surgery team is experienced in managing medication and may be able to suggest changes to improve the control of your seizures. However, it is worth remembering that with each new medication, the chances of your seizures becoming completely controlled becomes less.

Issues to think about

What are your reasons for considering epilepsy surgery? Take some time to think about what would change in your life if your seizures improved. It may help to write things down. 

Surgery for epilepsy aims to improve your quality of life by reducing the number of seizures you have, and hopefully stop them all together. It can take time to get used to not having seizures, and improvements in self-confidence and self-esteem will not happen overnight. It will take time, and you may require additional help and support.

If you hope to regain your driving licence, remember, even one minor seizure a year will prevent you from doing this. If resective surgery is successful, and you are seizure free, damage to your vision caused by the surgery, which is not noticeable in everyday life, may still mean you are not eligible to drive.

Some people consider surgery because they want to stop taking daily medication. After surgery, most people will not stop taking medication completely. If you are seizure free after one year, the consultant may advise reducing the amount of medication you take; but it is likely you will continue to take some form of drugs for the foreseeable future.

What to do if surgery is not an option

Assessment for surgery is a complex process and the epilepsy surgery team take many factors into account when making a decision. If the results of the investigations show that surgery would not be the correct treatment choice for you, this decision would not have been made lightly. We will try to keep you fully informed during the assessment process and encourage you to ask questions as you go along. Although it may not be possible to give you an answer until the assessment is completed, wherever possible, we will try to warn you during the assessment process if it looks like your chances of being offered surgery are low.

The consultant neurologist will invite you to an outpatient appointment where the results of the tests will be discussed, along with the reasons why surgery is not suitable for you. 

It may be that your seizures start in more than one place, or that the chances of becoming seizure free are very low. Alternatively, where your seizures begin may mean an operation would leave you with new problems. 

Sometimes the risks of the surgery may outweigh the potential benefits, therefore further attempts at drug treatment are recommended. This does not mean that surgery cannot be re-considered at a later date if all other options have been tried and the risks of surgery are thought to be justified.

If surgery is an option

You will meet with the neurosurgeon and discuss the surgery available. They will explain the risks and outline the aims of surgery. They will give you an estimation of your chance of seizure freedom. 

You will then be asked to decide if you wish to go ahead with surgery. You are welcome to think about this and let us know your decision at a later date.