What do epileptic events look like?
If an event is epileptic in nature or a non-epileptic event?
What is Video-EEG Monitoring?
What causes epilepsy?
What tests are used to determine the cause of epilepsy?
What is epilepsy?
How is epilepsy treated?
What happens when patients do not respond to medications?
What are non-epileptic events?
What are the alternatives for patients with epilepsy that do not respond to medications?
What are experimental antiepileptic medications?
What is the ketogenic diet?
What is the vagus nerve stimulator?
Who may benefit from epilepsy surgery?
What tests are necessary to confirm the location of the epilepsy?
How frequent is epilepsy?
How is epilepsy diagnosed?

What do epileptic events look like?
Epilepsy may present in many different ways. Depending on which region of the brain is involved in the seizure, a variety of clinical events may be observed. As the brain controls a myriad of functions, a seizure may express itself in extremely diverse ways. Motor movements are most easily recognized, and can range from a single jerk of a small muscle to rhythmic jerks involving the entire body. Occasionally there may be loss of all muscle tone resulting in a fall or drop attack. Other types of seizures involve regions of the brain governing sensation. During these seizures, the patient will experience an alteration of normal senses. Examples include episodes of strange smells and tastes, visual and auditory hallucinations, and tactile changes, such as a feeling of pins and needles or numbness. The brain is also involved in higher-level functions, such as thought processing, emotion, and memory. These functions are not immune to the effects of seizures. As a result, manifestations such as confusion and unusual behavior are also commonly seen. However, many neurological and psychiatric conditions, as well as normal behaviors in infants and children, can mimic an epileptic event. These episodes are referred to as non-epileptic events. On occasion, we are unable to characterize an event accurately or to differentiate it as either epileptic or non-epileptic based on a description of the episode. At this point, further testing is required.

If an event is epileptic in nature or a non-epileptic event?
What testing is required to characterize the type of epilepsy? How do you determine

When we need to characterize a type of epilepsy or differentiate true epilepsy from the non-epileptic variety, we perform an electroencephalogram (EEG). This is a study that analyzes the electrical activity of the brain (brain waves). In patients with epilepsy, we often find abnormalities that can assist in the diagnosis. The most common and characteristic abnormality is known as a spike discharge. This discharge is aptly named, as it resembles a spike. The location of the spike will help us to determine the location of the seizures focus (the part of the brain involved with the seizures). The most definitive information by far is obtained if the patient actually experiences a seizure during the EEG test. As most routine office EEGs last less than one hour, the clinician's chance of witnessing a seizure during the test is unlikely unless the seizure events are very frequent. In cases where a diagnosis remains elusive, more prolonged monitoring is required to increase the likelihood of recording a seizure. This is accomplished by a procedure called Video-EEG monitoring.

What is Video-EEG Monitoring?
Video-EEG monitoring is a more advanced test used in the diagnosis and classification of seizures. Patients are admitted to a room in the hospital that has been specially equipped for this test. The doctors, nurses, and technicians who are involved are highly trained in treating seizures. Electrodes are applied to the patients' head as in a routine EEG. Data from these electrodes is obtained continuously while a camera positioned in the room record all of the patient's actions. In the event of a seizure, the electrical activity of the brain during the episode can be accurately analyzed. Camera recordings made during the events allow correlations to be made between the abnormal electrical activity produced during a seizure and the simultaneous behavior of the patient. In patients with infrequent seizures, Video-EEG monitoring may be required for several days to increase the probability that a seizure event is recorded.

What causes epilepsy?
There are different reasons a person develops epilepsy. In some patients, a region of brain tissue may be abnormal or damaged. This lesion acts as a focus and trigger of seizure activity. Such lesions can be produced by a variety of reasons. Examples include lack of oxygen at birth, brain tumors, strokes, infections such as encephalitis or meningitis, head injuries, or developmental brain malformations. Some patients have a genetic predisposition (family history of epilepsy) to the development of epilepsy. In many patients, there is no obvious cause for the patient's seizures. This type of epilepsy is called idiopathic.
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What tests are used to determine the cause of epilepsy?
Various tests are used to assess the cause of epilepsy. Magnetic resonance imaging (MRI) provides a highly detailed picture of the brain and its intricate structure. Special imaging techniques and sequences specific to epilepsy are utilized (epilepsy protocol). With this special epilepsy protocol, small brain lesions that may go undetected with a routine MRI are readily discovered.
Another test used in the investigation of epilepsy involves metabolic screening, which examines numerous biochemical products. Various enzyme defects result in a deficiency or overabundance of these substances. Abnormal concentrations of these molecules, resulting in neuronal dysfunction, may provoke seizures.
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What is epilepsy?
The brain is by far one of the most complicated structures known to exist. The understanding of how this magnificent organ functions is still largely unknown and remains one of medicine's great mysteries. The basic building blocks of the brain are cells called neurons. Millions of neurons normally communicate in exacting harmony by way of electrical and chemical signaling. During a seizure, an area of the brain begins to discharge abnormally. This abnormal discharge may remain confined to a specific region or spread to involve other areas of the brain. The neurons involved in a seizure are unable to perform their normal activities. As a result, the functions that these neurons subserve may either be temporarily inactivated or excessively stimulated. Depending on which area of the brain is involved in the seizure, a variety of clinical signs may be observed. Alteration of consciousness, abnormal movements and sensations, staring, and behavioral changes are some of the manifestations of seizure activity.
Epilepsy is defined as the disorder characterized by recurrent seizures.

How is epilepsy treated?
For the majority of patients with epilepsy, seizure control can be achieved by the use of antiepileptic medication. With the advances made over the last decade in biopharmaceutical and neuroscience research, numerous new antiepileptic medications have recently been introduced into the market. Each type of epilepsy responds differently to these medications. A specific seizure type may respond dramatically to one antiepileptic medication, while another medication may have no effect on the seizure frequency. In some cases, an inappropriate antiepileptic medication may actually exacerbate the seizures. Therefore, accurate characterization of seizures and epilepsy is absolutely vital. For example, patients with partial seizures and epilepsy will respond better to carbamazepine (Tegretol), phenytoin (Dilantin), valproic acid (Depakote/Depakene), gabapentin (Neurontin), lamotrigine (Lamictal), topiramate (Topamax), tiagabine (Gabitril), levatiracetam (Keppra) or zonisamide (Zonegram) or Lacosamide (Vimpat). Patients with generalized seizures and epilepsy will respond better to valproic acid, lamotrigine, topiramete or zonisamide. Absence epilepsy, a generalized type of epilepsy once termed Petit Mal epilepsy, will respond to ethosuximide (Zarontin).

Most patients will respond to treatment with one anticonvulsant. However, some patients may need two or more medications to control their seizures. It is important that the doctor prescribing these medications be very familiar with their properties, as many potential interactions exist.

Another area of concern is medication side effects. Since all antiepileptic medications have side effects, the physician must be thoroughly aware of all the factors surrounding the use of the medication. The choice of antiepileptic medication should be based on the patient's seizures type balanced with the risk of side effects that are acceptable to the patient. For example phenytoin is an excellent antiepileptic medication for a variety of seizure types, but because of its potential for cosmetic side effects, such as changes in the appearance of gum and excessive hair growth, the use of this medication in adolescent and teenage patients should be reconsidered if another suitable medication could be used.

What happens when patients do not respond to medications?
Occasionally, a patient will not respond to medication. When this occurs, the first task is to determine if the patient's seizures have been misclassified. Misclassification of seizure type can result in the inappropriate use of medications with only little to no effect on the patient's seizures. In order to ensure proper classification of seizures, we recommend Video-EEG monitoring. Results from this study may lead to changes being made in medications and subsequent  improvements in epilepsy.  

In the event that some patient's seizures cannot be controlled with medication, the results of monitoring may show that they are potential candidates for epilepsy surgery.

It is also not unusual that the results of Video-EEG monitoring may prove that patient's seizures are non-epileptic in nature.

What are non-epileptic events?
One reason that a patient may not be responding to epilepsy treatment is that he/she may be experiencing Non-epileptic events.
Approximately 25% of the cases referred to epilepsy centers with the diagnosis of intractable epilepsy are Non-epileptic events. The term non-epileptic event represents a broad spectrum of behaviors, movement disorders, and psychological disturbances that can mimic a true epileptic seizure. Among the most common are seizures associated with psychological \ emotional difficulties, fainting spells, breathholding spells, gastrointestinal reflux, and disorders of movement. Unusual behavioral responses are often confused with true epilepsy, especially in infants. Common conditions such as gastro-intestinal reflux in the infant may result in spasm-like movements as they respond to the unpleasant sensation produced by the reflux of gastric acids.  Psychological non-epileptic events are typically stress induced and can become chronic without timely diagnosis. Since the management of these other conditions is completely different from that of epileptic seizures, the correct diagnosis is of paramount importance.

What are the alternatives for patients with epilepsy that do not respond to medications?
Even if a patient continues to have epileptic seizures despite treatment with various medications, several options still exist. These include experimental anti-epileptic medications, the ketogenic diet, the vagus nerve stimulator, and epilepsy surgery.

What are experimental antiepileptic medications?
Some medications are not currently approved for marketing by the Food and Drug Administration (FDA). These medications are available at certain epilepsy centers that are involved in research studies. The patient first must qualify as a suitable candidate under very specific criteria defined by the study. For example, a patient may be excluded from the study if his or her seizures are of a different type then that being investigated. Once the patient is enrolled in a study, he or she often must follow strict protocols, such as having frequent blood work performed and filling out questionnaires.

What is the ketogenic diet?
The ketogenic diet is a special diet consisting primarily of foods rich in fat and low in carbohydrates and proteins. When fats are metabolized in the body, they yield a product called ketones. For reasons not completely understood, the presence of these ketones has a protective effect against seizure activity. The diet is used primarily in children with a condition known as Lennox-Gastaut Syndrome who continue to have seizures despite treatment with antiepileptic medications. Most other seizure types do not respond to the diet. One of the drawbacks of this treatment is that it is very difficult for parents to administer. Meticulous measuring and weighing of foods, as well as urine testing is required to ensure appropriate ketone levels. Another drawback is that the diet is very difficult for patients to adhere to, as many find it unpalatable.

What is the vagus nerve stimulator?
This is a two-part device requiring surgical implantation.
One part is a wire that is wrapped around the Vagus Nerve in the neck, and the other part, resembling a pacemaker is
implanted under the skin beneath the Collar Bone.
The device is programmed to "fire" an electrical impulse, on a regular basis or on "demand" via a magnet.
This system may reduce the frequency or severity of seizures.

Who may benefit from epilepsy surgery?
Two criteria are generally required for a patient to be considered an epilepsy surgical candidate. The first is that the patient's seizures all start in the same part of the brain. The second is that that area of the brain does not control any important functions, such as speech, movement and sensations.

The overall goal of epilepsy surgery is to remove the epileptic focus (the part of the brain causing the seizures) while preserving normal function. For this purpose, a complex, extensive presurgical investigation by an epileptologist is required to localize the seizure focus that is going to be resected by the neurosurgeon. First, the patient undergoes non-invasive Video-EEG monitoring. The goal of this evaluation is to record several seizures in order to establish where the seizures originate. After this evaluation, if all of the patient's seizures are found to come from a single focus, surgery is considered a viable option.

Occasionally, some patients will have seizures that while seeming to come from a single focus, cannot be accurately pinpointed.

A second phase of tests is then performed before surgery can proceed. The first goal of this round of tests is to confirm the location of the epileptic focus found with video-EEG monitoring. The second goal is to ensure that the area of the brain that will be removed does not control important functions.

If all the information obtained in the presurgical evaluation fits with the localization of the focus responsible for the seizures, and there is no evidence of possible postsurgical complications, epilepsy surgery is performed.

What tests are necessary to confirm the location of the epilepsy?
Three imaging studies are usually performed as part of the presurgical evaluation. These include Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET), and Single Photon Emission Computed Tomography (SPECT).

Magnetic resonance imaging of the brain is a technique used to visualize abnormalities in the structure of the brain. In some cases, these abnormalities are focal lesions such as tumors, strokes, results of head injury, or developmental anomalies such as focal cortical dysplasia. In other cases, volume loss (smaller size) may be noted in certain brain structures. This suggests that they may have been damaged by seizure activity. Certain areas of the brain, such as the hippocampus of the temporal lobe, are known to be highly epileptogenic (seizure-producing) in nature. Measurements of the volume of the hippocampus using three-dimensional techniques allow us to determine whether it is potentially epileptogenic.

Positron emission tomography is a test used to visualize the metabolic activity of the brain. A radio-nucleotide associated with glucose (18F- fluoro-deoxi-glucose) is given intravenously to the patient. A scan is then performed to detect the concentration of this radio-nucleotide throughout the brain. Areas of the brain that are less metabolically active will consume less glucose and will contain lower concentrations of radio-nucleotide. Those areas of the brain that consume less glucose (hypometabolic areas) usually correlate with the seizure focus.

Single photon emission computed tomography is a test used to visualize the rate at which blood perfuses regions of the brain. A compound attached to a radioactive tracer molecule (99m-Technetium) is given intravenously during the time at which the seizure occurs. The radioactive tracer leaves the blood vessels and becomes trapped within the brain cells. Areas of the brain that receive more blood perfusion will have higher concentrations of the tracer in their cells. It is known that during a seizure there is increased blood perfusion in the region of the brain where the seizure originates. A scan is performed afterward that detects these areas of increased perfusion.

How frequent is epilepsy?
The estimated risk of developing recurrent seizures, or epilepsy, is between 0.5% and 1%, which represents approximately 1,500,000 to 3,000,000 people in the United States. The risk of a person having a single seizure is even greater. About 10% of the population will experience a seizure during their lifetime. This data underscores one important fact: the majority of people who have a seizure do not develop epilepsy.

How is epilepsy diagnosed?
We make the diagnosis of epilepsy based on the description of the events as described to us by patients, family members, or their caregivers. The majority of the time this information will be sufficient to make an accurate diagnosis. On occasion, such information may not provide enough insight to yield an accurate diagnosis. At this point, further testing of the patient is required to confirm the diagnosis.
There are many categories of epilepsy. The treatment of each type is highly specific; therefore, the proper diagnosis and classification of seizures is mandatory.