Why eeg test

Your healthcare provider then interprets the reading. During an EEG, your healthcare provider typically evaluates about pages, or computer screens, of activity. He or she pays special attention to the basic waveform, but also examines brief bursts of energy and responses to stimuli, such as flashing lights. Evoked potential studies are related procedures that also may be done. These studies measure electrical activity in your brain in response to stimulation of sight, sound, or touch.

The EEG is used to evaluate several types of brain disorders. When epilepsy is present, seizure activity will appear as rapid spiking waves on the EEG. People with lesions of their brain, which can result from tumors or stroke, may have unusually slow EEG waves, depending on the size and the location of the lesion. The test can also be used to diagnose other disorders that influence brain activity, such as Alzheimer's disease, certain psychoses, and a sleep disorder called narcolepsy.

The EEG may also be used to determine the overall electrical activity of the brain for example, to evaluate trauma, drug intoxication, or extent of brain damage in comatose patients. The EEG may also be used to monitor blood flow in the brain during surgical procedures. The EEG has been used for many years and is considered a safe procedure. The test causes no discomfort. The electrodes record activity. They do not produce any sensation.

In addition, there is no risk of getting an electric shock. In rare instances, an EEG can cause seizures in a person with a seizure disorder. This is due to the flashing lights or the deep breathing that may be involved during the test. If you do get a seizure, your healthcare provider will treat it immediately.

Other risks may be present, depending on your specific medical condition. Be sure to discuss any concerns with your healthcare provider before the procedure. Ask your healthcare provider to tell you what you should do before your test. Below is a list of common steps that you may be asked to do. An EEG may be done on an outpatient basis, or as part of your stay in a hospital.

EEGs are very safe. If your child has a seizure disorder, your doctor might want to stimulate and record a seizure during the EEG. A seizure can be triggered by flashing lights or a change in breathing pattern. You can help prepare your child for an EEG by explaining that it won't be uncomfortable. You can describe the room and the equipment that will be used, and reassure your child that you'll be right there for support. For older kids, be sure to explain the importance of keeping still while the EEG is done so it won't have to be repeated.

If you have questions about the EEG procedure, speak with your doctor. You can also talk to the EEG technician before the exam. Reviewed by: KidsHealth Medical Experts. Larger text size Large text size Regular text size. Preparation If your child is having an EEG, preparation is minimal.

Getting the Results A neurologist a doctor trained in nervous system disorders will read and interpret the results. Risks EEGs are very safe. An EEG can also play a role in diagnosing other brain disorders.

An EEG can determine changes in brain activity that might be useful in diagnosing brain disorders, especially epilepsy or another seizure disorder. An EEG might also be helpful for diagnosing or treating the following disorders:. An EEG might also be used to confirm brain death in someone in a persistent coma. A continuous EEG is used to help find the right level of anesthesia for someone in a medically induced coma. EEGs are safe and painless. Sometimes seizures are intentionally triggered in people with epilepsy during the test, but appropriate medical care is provided if needed.

During an EEG , flat metal discs electrodes are attached to your scalp. In a high-density EEG , shown here, the electrodes are closely spaced together. The electrodes are connected to the EEG machine with wires. Some people wear an elastic cap fitted with electrodes, instead of having the adhesive applied to their scalps. You'll feel little or no discomfort during an EEG. The electrodes don't transmit any sensations. They just record your brain waves.

Here are some things you can expect to happen during an EEG :. A technician attaches discs electrodes to your scalp using a special adhesive. Sometimes, an elastic cap fitted with electrodes is used instead. The electrodes are connected with wires to an instrument that amplifies the brain waves and records them on computer equipment.

Once the electrodes are in place, an EEG typically takes up to 60 minutes. Testing for certain conditions require you to sleep during the test. In that case, the test can be longer.