The surgical treatment of epilepsy is a valuable option for well-selected patients.  Patients who are not adequately treated with medications, who are proven to have a localized seizure focus, and who can accept the risks and consequences of surgery are candidates for surgery.  The most common location of seizure focus in adults is in the temporal lobe, where surgical removal is associated with a seizure-free rate of ~60-70%.  This patient population with temporal lobe epilepsy (TLE) has the greatest success rate from surgery.  A large study comparing surgery versus treatment with medications for TLE showed that 58% of the surgically treated patients were free of disabling seizures compared to 8% of the patients treated with medications alone.  However, treatment with medications is still first-line and surgery is reserved for intractable cases.  Most patients recover extremely well after surgery, including patients undergoing temporal lobectomy, with little disability attributable to the procedure.

Primary generalized (idiopathic) epilepsy is rarely aided by surgery, although vagal nerve stimulation (VNS) is an option.  Generalized epilepsy occurs when multiple different areas of the brain exhibit seizure activity, so no single area can be resected to decrease the seizures.  VNS involves placing an electrode around the vagal nerve, usually on the left side.  The theoretical mechanism of VNS is alteration of diffuse signals throughout the brain to suppress the generalized spread of seizure activity after it starts.

Other surgical treatments are tailor-made for specific problems.  Corpus callosotomy (CC) is used to stop the transmission of seizure activity from one side of the brain to the other.  Patients who suffer seizures that spread from one side to the other may suddenly fall to the ground during their seizure leading to a high risk for injury.  CC prevents this spread of seizure activity.  Hemispherectomy is a term used when the patient’s entire half of the brain is removed, or “disconnected” from the rest, when the entire side is dysfunctional due to widespread seizures.  Both CC and hemispherectomy are rare procedures used for very carefully selected patients.  Multiple subpial transection (MST) is another procedure that is used in carefully selected patients who have seizures that start in important areas of the brain that cannot otherwise be removed without causing extensive neurologic dysfunction.

New epilepsy research focuses on computer devices that are implantable.  These systems, such as Neuropace, use a computer to detect the very first signs of a seizure and then give a localized electric shock (similar to a cardiac defibrillator) to the part of the brain where the seizure is starting.  This then stops the seizure activity before it can spread to other areas of the brain.  Other implantable devices use a similar computer to detect the first signs of a seizure and then release an anti-seizure medication directly into the brain to disrupt the seizure activity.  These devices are still in early trials.

For a patient evaluation or possible surgical treatment of epilepsy, please call The Neurosurgery Center of Colorado at 303-481-0035 to make an appointment with Dr. Adam P. Smith, MD.

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