Surgery to treat ]]>epilepsy]]> is most likely to be successful when:

  • Seizures occur in just one part of the brain (partial or focal seizures)
  • Seizures begin as partial seizures before spreading to the rest of the brain
  • Medicines do not control the seizures or they cause severe negative side effects
  • It is used to remove the underlying cause of the seizures, such as a ]]>brain tumor]]> or excess fluid on the brain
  • There is unilateral multifocal epilepsy with infantile hemiplegia (such as ]]>Rasmussen’s encephalitis]]>)

Before the decision to undergo surgery is made, however, you and your doctor must consider the following factors:

  • Frequency and severity of your symptoms
  • The area of the brain involved, and the importance of that area to everyday life

The main types of surgery used to treat epilepsy are:

Lobectomy or Lesionectomy

This procedure involves removal of the area of the brain that is producing the seizures, called the seizure focus. It is only appropriate in patients who have partial seizures that originate in just one part of the brain. The surgery is successful 50%-90% of the time.

Multiple Subpial Transection

This involves a series of cuts along the nerve path by which seizure impulses spread. The surgery is designed to prevent seizures from spreading into other parts of the brain, while leaving the patient’s normal abilities in place. This is sometimes done alone and sometimes done in addition to a lobectomy. Alone, it is done in patients whose epileptic seizures originate in a part of the brain that cannot be removed. This surgery improves seizure control in about 70% of the time. Multiple subpial transection is less often done than a lobectomy.

Corpus Callosotomy

This surgery involves cutting the nerve connections between the right and left hemispheres of the brain to prevent seizures from spreading from one side to the other. It is often done in two steps. The first operation partially separates the two halves of the brain, but it leaves some connections in place. If the generalized seizures stop, no additional surgery is done. If seizures continue, a second operation that completes the separation may be done.

Corpus callosotomy is done primarily in children with severe seizures that start in one hemisphere of the brain and spread to the other. The surgery can help prevent generalized seizures. However, the surgery does not prevent seizures in the side of the brain where the seizure originates.


This surgery involves the removal of half of the brain's outer layer (cortex). It is usually done only in children whose epilepsy is not responding well to medicine and who have one of these conditions:

  • Rasmussen’s encephalitis
  • Other severe damage to one brain hemisphere

Recovery requires intense rehabilitation in order to regain normal functions. However, after this surgery, children usually:

  • Have seizures greatly reduced or even eliminated
  • Recover well from the surgery
  • Often recover nearly normal activities—However, there will be:
    • Weakness and loss of some movement on one side of the body
    • Loss of peripheral (side) vision

About half of patients need to remain on their medicines after this surgery. And, about half can slowly be tapered off medicines if they are seizure-free for 12 months.

The chance of recovery from this surgery is best in young children. Therefore, a hemispherectomy is done as early as possible in a child’s life and almost never done in children over age 13.