Surgical resection (removal of abnormal tissue) for epilepsy may fall into the broad categories of lesionectomy, lobectomy, multilobar resections, and hemispherectomy.
A lesion is a generic term for brain abnormalities that show up on imaging. Some types of lesions, such as cavernous malformations (blood vessel abnormality) and tumors, are prone to cause seizures. When the preoperative testing indicates that these lesions are the cause of the epilepsy, they can be removed surgically.
The brain is divided into separate lobes such as the frontal lobe, temporal lobe, parietal lobe, and occipital lobes. Seizures may arise from any of the lobes. Lobectomy is an operation to remove a lobe of the brain. Removal of one of the temporal lobes, a temporal lobectomy, is the most common type of epilepsy surgery performed. Other types of lobectomies may rely on more specialized testing and surgery to prove a lack of vital function.
A multilobar resection involves removal of parts or all of two or more lobes of the brain. It is reserved for more widespread abnormalities causing seizures, providing that no vital functions are in the candidate regions.
The brain is divided into two halves, or hemispheres - a left and a right. In rare instances, children may have severe, uncontrollable, and devastating seizures that can be associated with weakness on one side of the body. This may occur with a large amount of damage or injury to one of the hemispheres. Surgery to remove or disconnect a hemisphere, a hemispherectomy, may be curative. There are many subtypes of this surgery, the two main divisions being anatomic and functional hemispherectomy.