White-Wilson Medical Center

EEG Tests EEG Tests

The Electroencephalogram (EEG) is a recording of the on-going electrical activity of the brain.

An EEG can assist in the diagnosis of a variety of neurological problems - from common headaches and dizziness to seizure disorders, strokes and degenerative brain disease. The EEG is also used to determine organic causes of psychiatric symptoms and disabilities in children and can assist physicians in determining irreversible brain death.

What is the difference between seizures and epilepsy?

Seizures are a symptom of epilepsy. Patients may experience unusual smells, visual symptoms or feelings prior to a seizure. Epilepsy is the underlying tendency of the brain to produce sudden bursts of electrical energy that disrupt other brain functions.

Epilepsy is a brain disorder in which clusters of nerve cells, or neurons, in the brain sometimes signal abnormally. Epilepsy is a permanent brain condition that affects the delicate systems governing how electrical energy behaves in the brain, making it susceptible to recurring seizures.

What if I only have one seizure?

Having a single seizure does not necessarily mean a person has epilepsy. High fever, severe head injury, lack of oxygen and a number of other factors can affect the brain enough to cause a single seizure. You should contact your physician immediately to determine what type of seizure event occurred.

How is epilepsy diagnosed?

Epilepsy is diagnosed through detailed medical history and a series of medical tests.

Is it necessary to be in the hospital for all EEG tests? No. Ambulatory EEG allows the patient to go about their daily business at home, school or work, where the patient will more likely feel the stress of daily life and in places where their seizures or events might take place.

Is Epilepsy ever contagious?

No. It can be caused by many factors, but it is not contagious.

Once diagnosed and treated, how can I guard against having additional seizures?

Take your prescribed medication regularly. Maintain regular sleep cycles. Avoid unusual stress. Work closely with your physician and have regular medical check-ups.

Learning more about our Ambulatory EEG Test

If your physician orders an Ambulatory EEG to diagnose your medical problem, you will be referred to our service center. This involves a one to two hour education and set-up session.

Once set-up you may return to work or home, depending on the physician's recommendation. For instance, if your seizures only happen at the office, the physician may recommend that you return to work. If that is not the case, most patients choose to stay home due to the electrodes, wiring and head-wrap. The test may take from one to three days, depending on the orders of your physicians.

See your physician.

When a child or adult has never had a seizure before, the first seizure is usually followed by a careful medical examination.

Physicians use both diagnostic tests and careful evaluation of the seizure itself to determine a plan of care. Age, family history and possible causes of the seizure are among the factors that are considered.

If the physician feels that diagnostic testing is warranted, an Ambulatory EEG test may be ordered. This is an accurate way to diagnose both epileptic and non-epileptic seizure disorders.

Having an ambulatory EEG Test.

Diagnostic EEG testing can be done on an ambulatory basis. You will come to our service center for an Ambulatory EEG "set-up" and then you're free to go home or return to work during the testing process (which typically takes from one to three days, depending on your physician's order).

During the set-up, a caring and highly skilled technologist will educate you on the process and answer your questions about this safe and painless procedure. Sixteen to 24 electrodes will be placed on your head using a conductive paste and special glue to hold the electrodes in place. The paste and glue will be cleaned from your head at the end of the study.
Your electrodes, small metal discs with thin wires, will be connected to a miniaturized, head-mounted amplifier, which records the results of your test. The electrodes pick up tiny electrical charges which are produced by activity of the nerve cells in the brain.

Once your set-up is completed, your head is wrapped with gauze to hold the electrodes, wires and amplifier in position. Our technologist will provide you with supplies and instructions for your use during your test and the disconnection process following your test. You are able to return to work, although most patients choose to stay at home during the test.

Analyzing your results.

Your brain wave activity will be electronically stored and then downloaded onto a computer for your physician. Your physician will interpret the brain patterns and be able to determine the treatment that is best for you.

Benefits of ambulatory EEG Testing.

In a multi-center university hospital publication, Drs. Liproace, Tatum, Morris and French determined that 50% of all identified seizures were detected by the automatic detection software. Previous diagnostic efforts with routine EEGs performed on the same group of patients did not detect any events. From these studies, patients and parents can see the benefits of an Ambulatory EEG in the diagnosis and treatment for seizure disorders.

Why physicians order Ambulatory EEG Tests.

An ambulatory EEG will let your physician evaluate your brain patterns while going about your daily routine at home, school or work. This exposes you to the daily stressors that may be causing the events or seizures to occur.

For patients with known seizure disorders, the 20-30 minute recording time of the routine EEG done in an office or hospital lab might be too short to capture all the different episodes. It's common for patients to forget events. A careful history taken by your physician is very important in your diagnosis. But, if you are unable to recall specifics as a result of your condition, you may be unable to give your physician a complete picture. An ambulatory EEG recording will store these episodes for your physician's review.

If you are already taking medication, an ambulatory EEG will help to evaluate your response to specific drug therapy. Many times, events will occur at night and cannot be captured by a routine 20-minute EEG.

Ambulatory EEG helps to evaluate clinical episodes that do not correlate with your brain wave data.

Often your heart will be monitored along with your brain waves. Sometimes symptoms are the result of cardiac events captured in an ambulatory EEG.

An ambulatory EEG is a means of recording long-term clinical data without having to be admitted to the hospital, resulting in greater convenience and less cost.

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