Definition: Epilepsy or seizure disorder is a symptom of disturbed electrical activity in the brain. The nervous system is electrical, with impulses constantly shuttling between billions of neurons (nerve cells) and the parts of the body involved in various activities both voluntary (such as walking) and involuntary (such as breathing). Nerve cells may malfunction, causing the normally smooth-running pattern of electrical activity to be disrupted. The damaged cells "overload," becoming over-excited and giving off too much electricity. The result of this temporary overload is a seizure that causes some of Dr. Aniruddh Kulkarni the body's activities to go awry: there's a sudden loss or disturbance of consciousness often in association with motor activity; there's no pain associated with the seizure and usually no long-term after effects. Those whose epilepsy is controlled by medical treatment may experience no seizures at all. Approximately 2.5 million people in the U.S. alone suffer from epilepsy. It is really many diseases but they all have in common the repetitive occurrence of epileptic seizures. These seizures can occur in a small region of the brain (partial seizures) or throughout both of the brain’s hemispheres (generalized seizures). Epilepsy can strike at any age, but it is especially common in children and the elderly.

Evaluation

Evaluation for an accurate diagnosis is the first step. Epilepsy can be confused with other conditions such as syncope, stroke and certain psychological disorders. Several tests are used in the evaluation of epilepsy. An EEG records patient’s brain wave activities. For patients being considered for epilepsy surgery, inpatient EEG monitoring, an MRI of the brain or PET scan and neuropsychological testing may also be ordered. Once the appropriate tests have been accomplished, the surgical candidate will be evaluated by a multi-specialty team to determine if they would be an appropriate candidate for surgery.

Accurate diagnosis of the type of epilepsy a person has is crucial for finding an effective treatment. There are many different ways to treat epilepsy. Currently available treatments can control seizures at least some of the time in about 80 percent of people with epilepsy.

Treatment Options

Vagal nerve stimulator may be considered for complex partial seizures and the other forms of epilepsy that are resistant to medical therapy. In patients who are not candidates for open, traditional resective surgery, a vagal nerve stimulator may be used. This implanted device, attached to the left vagus nerve, has been shown in multiple studies to reduce the seizure frequency and intensity by 50% or more in 30% of the patients nine months after the onset of stimulation. With additional stimulation (i.e., greater than 18 months), 54% of the patients develop a 50% or better reduction in seizure frequency and intensity. The procedure itself takes approximately one and a half hours, and the patients usually go home the next day. The procedure has very few risks.

Cortical mapping is a technique used to localize both the region of the brain generating seizures as well as areas that are responsible for thought and movement. There are various ways of mapping the brain. Noninvasive systems like fMRI, PET, MEG, SPECT can give a good starting point for localization of seizures and thought processes. However, the detail and resolution needed to plan a surgical resection often requires direct recording from the surface of the brain. To do this, surgeons will place a grid electrode directly on the surface of the brain and then record in the operating room or close up the surgical site and record for some days with the electrodes in place, a so-called phase II recording.

Callosotomy is a surgical procedure in which the some or all of the corpus callosum is divided. The corpus callosum is the major fiber connection between the two halves of the brain. The procedure is primarily used to treat "drop attacks" seizures. Many centers are using a trial of vagal nerve stimulation before performing callosotomies.

Deep brain stimulation for epilepsy is currently under investigation. Although a number of early trials show promise, it has not yet developed to the point where it may be considered a viable alternative to traditional medical management. In some patients, chronic electrical stimulation through electrodes implanted deep in the brain can relieve some of the major symptoms of Epilepsy and Parkinson's disease. Based on results from about 30 patients, the FDA recently approved deep brain stimulation (DBS) within the thalamus for relief of tremor of Parkinson's disease and also for non-Parkinsonian "essential tremor."

Removal of the seizure focus is the most common type of surgery for epilepsy, removing a small area of the brain where seizures originate. This is also referred to as a lobectomy or lesionectomy.