What is an (EEG) Electroencephalogram?
An EEG (Electroencephalogram) is a safe and painless test that records electrical activity of the brain. The brain is actively at work at all times throughout life, even during sleep. The electrical activity appears as specific patterns of wavy lines, hence the term brainwaves. By evaluating the pattern formed by the brain, EEG's are used to assist in the diagnosis of various brain disorders, such as epilepsy, strokes or other brain lesions. We also use EEG's to evaluate the effects of head trauma or in determining the consequences of severe infectious disease. In general, the EEG acts as an indicator of brain function and grossly defines areas of abnormal involvement.
How is an EEG done?
- Routine EEG's
At AMC Neurology Group, EEG's are performed by a certified technologist. The technologist applies electrodes (small medal disks) to your scalp with an adhesive gel or paste. This is a painless procedure and the gel or paste is easily removed after the procedure. The electrodes pick up brain electrical activity and carry it by wires to a computer that amplifies the signals and stores them. The routine EEG takes approximately 35 to 45 minutes to complete.
- Ambulatory EEG's
Routine EEG's provide a relatively short sample of brain electrical activity, which is often sufficient for most patients. In some patients with epilepsy, however, this recording is normal or shows only minor, nonspecific findings. In such cases, an extended recording that includes long periods of wakefulness and sleep is desired.
An ambulatory EEG can record up to 72 hours of EEG activity with a special recorder that is slightly larger than a cassette player. This recorder allows you to go about your normal routine while the EEG is being recorded. The EEG technologist will attach electrodes on your head using special glue to keep them in place. The electrodes are connected by wires to the recorder which can be worn on your waist. The ambulatory EEG may last anywhere from 24 to 72 hours. The technologist will make an appointment for you to return for removal of the electrodes.
One of our board certified Neurologists will read, interpret and make the final report.