May 1, 2019 By ashwin
What are the different types of surgery used to treat epilepsy?
Different surgeries are available for different types of epilepsy. These include
Surgery that removes the area of the brain causing seizures is called a focal resection. The area of brain being removed is referred to as the “seizure focus,” meaning the place where seizures begin.
- Removing the seizure focus is the most common type of epilepsy surgery. It is an excellent treatment option for people who have seizures arising from one area of the brain.
- The chances of success are highest in people who have an abnormality on MRI (magnetic resonance imaging) that matches the area where seizures start on EEG (electroencephalogram)monitoring.
- Since it involves removing a part of the brain, it is reserved for people whose seizures arise from non critical brain regions. Examples of critical brain regions include areas that control speech, movement, memory, and vision.
Temporal Lobe Resection
Temporal lobe resection is removing a portion of the temporal lobe of the brain. The most common type of epilepsy surgery is an anterior temporal lobectomy. It has the highest rate of success. After surgery, approximately
- 60% to 70% of people are free of seizures that impair consciousness or cause abnormal movements.
- 20% to 25% of people may still have seizures that affect their awareness (focal impaired awarenessor tonic-clonic seizures). Although this group continues to have seizures, the majority of people show a large decrease, more than 85%, in the number of seizures they have.
- 10% to 15% of people do not have improvement in seizure control.
Overall, in people who are good candidates for a temporal lobectomy, more than 85% will have a significant improvement in seizure control. Most people will need to continue taking anti-seizure medications. Often, over time with the guidance of their epilepsy team, they are able to lower the dose of the medicine they need to take. About 25% of the people who become seizure free eventually can stop taking all of their seizure medications. Read a study about the long-term outcome after epilepsy surgery.
Frontal Lobe Resection
Frontal lobe resection refers to removing an area in the frontal lobe where seizures begin. It is the second most common location for epilepsy surgery.
- The frontal lobes of the brain control functions like motivation, attention, concentration, organization, planning, mood, and impulse control.
- People who have frontal lobe seizures may have problems with these functions before surgery.
- It is important to understand there may also be changes seen in these brain functions after surgery.
The success rates for frontal lobectomy are not as high as those for temporal lobectomy. It is still for many people who have drug resistant epilepsy. After surgery:
- Up to 50% of people are free of seizures that impair consciousness or cause abnormal movements.
- 20% to 40% of people may still have seizures that affect their awareness (focal impaired awarenessor tonic-clonic seizures). Although this group continues to have seizures, the majority of people have a large decrease in the number of seizures.
- A small number of people do not have any improvement in seizure control.
Although the success rate for frontal lobe surgery is not as high when compared to people who have temporal lobe surgery, there are still 70% of people who do have a great improvement in seizure control. Most people will need to continue taking anti-seizure medications. Often, over time with the guidance of their epilepsy team, they are able to lower the dose they need to take.
Parietal and Occipital Lobe Resection
The parietal and occipital lobes are located in the posterior (back) part of the brain. A parietal or occipital lobe resection is surgery to remove a part or one of these lobes.
In most cases, this type of surgery is performed when an area in these lobes is found to contain abnormal structure or a lesion. This type of epilepsy surgery is more likely to be successful when it involves a structural abnormality like a tumor of scar tissue.
Removing a lesion that causes focal seizures is called a lesionectomy. People with a focal (well defined) structural abnormality in the brain causing their seizures, such as a tumor or vascular malformation (abnormal blood vessel group), may be considered for this type of surgery. This operation involves removing the lesion and the area of surrounding brain tissue that is causing seizures.