Epilepsy - Surgery

Surgery

Surgical techniques to remove injured brain tissue may be appropriate for many patients with epilepsy. The surgeon's goal is to remove only the damaged tissue in order to prevent seizures and to avoid healthy brain tissue. Surgical techniques for reaching these goals have improved significantly over the past decades due to advances in imaging and monitoring, new surgical techniques, and a better understanding of the brain and epilepsy.

Tests to Determine if Surgery Is Indicated

A number of tests using imaging and electroencephalography (EEG) can determine if surgery is an option.

• The general approach is to first use long-term EEG monitoring to locate the brain tissue that triggers the epileptic event.
• Advanced imaging techniques can provide valuable additional information. They include functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), positron emission tomography (PET), or single-photon emission computer tomography (SPECT) scans.

If the imaging tests indicate that more than one site is involved or their results conflict, then more invasive monitoring of the brain may be required, although the newer imaging tests are proving to be very accurate tools. If such tests pinpoint a specific area in the brain as the location for seizures, then surgery is possible. MEG, for example, is now approved for imaging parts of the brain involved with motor control, sensation, and language function, and may become important in evaluating patients who are likely candidates for surgery. The doctor will also examine the test results to determine if the offending nerve cells perform vital functions and try to predict surgical outcome in certain cases.

Temporal Lobectomy

The most common surgical procedure for epilepsy is temporal lobectomy, which is performed when epilepsy occurs in the temporal lobe. (Surgery is not as successful in epilepsies that occur in the frontal lobe.) It involves removing small portions from the hippocampus. The hippocampus is a part of the brain that is involved in memory processing. It is part of the limbic system, which controls emotions.

Click the icon to see an image of the limbic system of the brain.