Featured Article: Epilepsy surgery - Enrique Feoli
Dr. Enrique Feoli, epileptologist and Associate Director of the Northeast Regional Epilepsy Group International Branch, sat down to answer our questions about brain surgery as a form of treatment for epilepsy. Dr. Feoli completed his training in Neurology and Epileptology at New York University Medical Center and New York Presbyterian Hospital-Cornell. He is Board Certified in Neurology and Clinical Neurophysiology. His research interests are primary generalized epilepsy, neurostimulation, and EEG in ICU monitoring.
1-What patients are likely candidates for Epilepsy Surgery (ES)?
Epilepsy surgery is considered an option for patients with epilepsy who have continued to have seizures despite being on 2 or more medications. However, having said this, before we can proceed with surgery, our team needs to ascertain that the patients epilepsy can be successfully and safely treated with brain surgery.
2- How would someone know that they are a good candidate for ES?
There are many steps that one needs to go through to make sure that the patient is a good candidate for epilepsy surgery. That includes performing the following tests:
a-Video EEG monitoring: This is a test that takes place at the hospital on the Epilepsy Monitoring Unit and lasts an average of 3-5 days. All medications are stopped so the doctors can record the patient’s epileptic seizures while undergoing a continuous EEG. The patient is filmed at the same time so the specific movements during the seizure can be compared to the EEG. By doing this, the doctors first off make sure that the patient’s episodes are truly epileptic seizures. This is a crucial step since there is a 30 % misdiagnosis of epileptic seizures in the general population. This means that out of every ten patients treated for epileptic seizures, 3 may have episodes that look like seizures but when they undergo Video-EEG monitoring it is concluded that they in fact do not have epilepsy.
Once the diagnosis of epilepsy if firmly established; video EEG is used to pinpoint the exact location where the seizure begins. This is crucial so that a targeted surgical procedure can be planned.
Patients who would not be considered good surgery are for example, those whose seizure starting points are broadly spread out in the brain (e.g., petit mal epilepsy) with no particular focus.
3- Are there any other tests that would be needed after going through the video EEG, before the surgery?
b. Once the patient is deemed a surgical candidate based on the Video EEG an MRI of the brain is performed. Doctors are looking for scars or lesions that might be the cause of the seizures.
c. Neuropsychological testing of memory and language is also requested prior to the surgery to identify memory strength in the temporal lobes and speech function.
d. In some cases, something called a Wada test is done. This is necessary to identify much more clearly where the speech and the memory centers are. This information is extremely important for the surgical team so that they know which brain sections can be safely removed and which should be avoided.
e. Other testing that might be requested depending on the specifics of the case are a magnetoencephalogram (MEG) to study deep brain structures, Postitron Emission Tomography (PET) to study the brain’s use of glucose, and the Single Photon Emission Computed Tomography (SPECT) to study brain blood flow.
4- What are the surgical procedures available today?
There are many available surgical procedures today. Brain resection (removal of a portion of the brain) is used to cure epilepsy (to obtain seizure freedom). Others are referred to as “palliative procedures” which means that the aim is to improve the epileptic condition rather than cure it. Examples of this include the Vagus Nerve Stimulator (VNS) that has been approved by the FDA, Deep Brain Stimulation (DBS) and Neuropace (that is not yet approved by the FDA).
5- What are the chances that epilepsy surgery will be successful?
The chances of seizure freedom depends on the part of the brain that is causing the seizures. Success rates go from 75 % seizure freedom (temporal lobe epilepsy) to 50 % (frontal lobe epilepsy or multi-focal epilepsy).
6- Can surgery fail?
Yes, there are patients that do not experience any improvement in seizure frequency or only a very slight improvement despite having had brain surgery. In those cases re-intervention (a repeat brain surgery) might be needed.
7- Can a patient stop taking medications for epilepsy after surgery?
Usually medications are continued for 2 years following the surgical procedure. After that we slowly taper off medication over a period of time. Our goal when performing epilepsy surgery is for the patient to have no more seizures and to be off all anti epileptic medications. However, some patients that are successfully operated will still need to remain on 1 or 2 medications for the rest of their life to maintain seizure freedom.
For more information about epilepsy surgery: http://www.epilepsygroup.com/epilepsy-information-detail5-59-14/epilepsy-surgical-treatment.htm
To make an appointment with one of our epileptologists to discuss surgical options, call 201-343-6676 or 914-428-9213
