Epilepsy Surgery – Who Can Benefit?
What is epilepsy?
Epilepsy means an elevated risk of recurrent unprovoked seizures. A seizure is caused by an abnormally high electrical discharge from a particular region of the brain which spreads to the neighboring areas. It is the fourth most common neurological disorder, affecting about one percent of the population. Epilepsy occurs in people of all ages.
What causes epilepsy?
Usually the cause of epilepsy is not known. When it is known, it is often from a brain lesion caused by an abnormal development of the brain, a stroke, a tumor, or scar tissue. A person who has two or more seizures not caused by a reversible medical condition like hypoglycemia is diagnosed with epilepsy.
What is drug resistant epilepsy?
Fifty percent of newly diagnosed patients with epilepsy will have good seizure control with one seizure medication. When a patient continues to have seizures despite using two well tried seizure medications, the chances of good seizure control is less than five percent with additional medication. This is called drug-resistant, or medically intractable, epilepsy. Around one third of all epilepsy patients have medically intractable epilepsy.
What treatment options do we have for drug resistant epilepsy?
The best therapeutic option for treating drug-resistant epilepsy is surgery. The other treatment options include vagus nerve stimulator (VNS), response neuro stimulator (RNS), ketogenic diet and drug trials.
How can we determine if a patient is eligible for surgery?
Not every patient who has drug-resistant epilepsy can be a good surgery patient. Patients go through a detailed pre-surgical workup, including five to seven days of continuous EEG monitoring to capture seizures, a brain MRI, and other diagnostic testing and scans. After all of the data is collected, the results will be presented to a multidisciplinary team who will decide if the patient is eligible for surgery.
What types of surgery are there?
Surgery is the only cure for medically unmanageable epilepsy.
- Single stage surgery – If the patient has a lesion in the brain or the phase one data all points to a precise area of the brain that is causing the seizures.
- Two stage surgery – If the patient doesn’t have a lesion in the brain but all the phase one data points to a broader area that is causing the seizures. To locate the seizure making area, the patient will first have EEG electrodes placed directly on the brain surface. The patient will then need to have seizures to pinpoint the area where they are coming from. Then the doctors remove the electrodes and the areas of the brain that are causing seizures.
- MRI guided thermal ablation – Visualase. This is a relatively newer technique used to remove small, isolated, deep, potential seizure making areas without major surgery.
- Corpus is a palliative surgery meaning, it is not a cure for epilepsy, but can reduce the seizure’s frequency and intensity.
What are the complications of epilepsy surgery?
Like any surgery, there can be side effects. These include infection, bleeding, stroke and anesthesia related complications, but all of these complications are uncommon. There are some specific but rare avoidable complications from epilepsy surgery like motor deficits, sensory deficits, visual field cuts and memory deficits.
What is the recovery time from the surgery?
It depends on the individual patient and if there are any complications. Depending on the type of surgery, a patient could go home anywhere from one to two days to several weeks after the procedure.