Epilepsy is a common disorder in the general population. The condition is usually treated with medications. However, if there is no response to the medications, certain surgical procedures may help the patients. The aim of surgery is either to excise the impaired region causing the epilepsy or to hinder the spread of epileptic activity. The purpose is to prevent epileptic activities as far as possible and boost the patient’s quality of life.
What Is Epilepsy Surgery?
The surgical interventions carried out for epilepsy can be divided into two main groups:
- Excision of the impaired brain region causing the seizures
- Hindering the spread of epileptic activity to other parts of the brain
Epilepsy surgery can be addressed under two groups, namely curative (complete elimination of epilepsy, achieving full recovery) or palliative (reducing spread of epileptic activity). The surgical procedure to be carried out for the patient is decided by a council in the light of the underlying cause of epilepsy, the diseased brain region and the type of epilepsy.
Types Of Epilepsy Surgery
- Curative procedures are performed if there is a certain brain region or focus that is the exact cause of seizures.
- A: Temporal lobectomy: This method is most commonly used for patients with temporal lobe epilepsy. In this procedure, a part of temporal lobe is removed along with the amygdala and hippocampus. Positive outcomes are achieved in approximately 70-80% of the cases.
- B: Cortical excision: In this surgery, the cerebral cortex (the outermost layer) that causes the epilepsy is removed. This surgery provides benefits for approximately 40-50% of the patients who undergo this surgery.
- C: Hemispherectomy: This procedure is performed quite rarely. Side-effects of the surgery may be serious.
- Palliative procedures are performed if a focus causing the epilepsy cannot be detected or if it is considered that surgical removal of the focus poses serious risks.
- A: Callosotomy: The structure that connects two hemispheres of the brain is called corpus callosum. Epileptic activity can spread to both halves of the brain through this path. Callosotomy is the procedure based on deliberate destruction of this structure. This procedure can also be performed with radiation (radiosurgery) in selected patients.
- B:Subpial transection: This procedure can be carried out if the focus of epilepsy is at an inoperable location such as speech center or motor cortex. Small incisions are made in these regions with very fine surgical blades and efforts are made to stop spread of the epileptic activity.
- C: Vagus nerve stimulation: The procedure involves whipping an electric cable around the vagus nerve and connecting the cable to a pacemaker under the collarbone. Electric current is transmitted to the nerve at certain intervals with an effort to suppress the epileptic activity in brain. Success rate of this method is less than 50%.