Electroencephalogram (EEG)

What is an electroencephalogram?

An electroencephalogram (EEG) is a test that measures the electrical activity in the brain, called brain waves. This is done through small, painless electrodes that are placed on your child’s scalp. Our trained registered technologists perform EEGs.

Why is an electroencephalogram performed?

Electroencephalograms are performed to detect problems in the electrical activity of the brain associated with certain neurological disorders. They can help diagnose several conditions including but not limited to:

• Epilepsy
• Head injury
• Encephalitis
• Brain tumors
• Encephalopathy

What to Expect During an Electroencephalogram

During an Electroencephalogram (EEG), your child’s head will be connected to an EEG machine via electrodes. The EEG technologist will then ask your child to perform various tasks, recording the electrical activity in the brain during these tasks.

At the beginning of the appointment, your child will be asked to lie down on a bed. The EEG technologist will measure your child’s head and makes small marks on the scalp with a washable marker or pen. Each marked area is then rubbed with a gritty lotion, allowing electrodes to transmit well. A gel is then put on the electrodes, which are applied to each of the marked spots on the scalp.

The electrodes are connected to the EEG machine and the test begins. Your child will need to sit or lie down as still as possible. He or she may be asked to breathe fast, look at flashing lights, or try to sleep. Your child’s doctor may order 24-hour EEG monitoring to study brain waves over a longer period of time. We also offer long-term EEG monitoring that your child’s doctor may order to study brain waves over a longer period of time. Learn more about long-term video EEG monitoring.

Once the test is complete, the electrodes will be removed and the gel will be washed off with warm water and a washcloth. Sometimes, all the gel will not come off and you may need to wash your child’s hair at home.

How should I prepare my child for an EEG?

Consider the following when preparing your child for an EEG:

• Wash your child’s hair the night before. Do not put any oil, gel or hairspray on his or her hair. If your child’s hair is long, do not braid or put it up. Hair extensions are also prohibited during an EEG.
• Unless otherwise directed, give your child his or her medications as usual. Bring a list of all the medications (dose and schedule) your child takes to the Neurodiagnostics Lab.
• Your child’s doctors will give you instructions about your child’s diet, including how long they should wait to eat before or after the EEG reading.
• On the day of the EEG, your child should not consume any drinks containing caffeine, such as caffeinated sodas, coffee or tea.

Where should I go for my child’s EEG?

Please check in at the main entrance of CHOC Hospital in Orange, 1201 W. La Veta Ave., Orange, CA 92868. It is located near the intersection of Pepper Street and La Veta Avenue. Parking is located immediately west of the hospital. Valet parking is also available at the entrance. Please arrive 30 minutes prior to your child’s test. You will check in at the Admitting desk, near the main entrance on the first floor of the hospital. Please bring your child’s insurance card. After registration, you will be escorted to the Neurodiagnostics Lab.

Are there any risks associated with an EEG?

Electroencephalograms are very safe and painless. Sometimes seizures or abnormalities are intentionally triggered during an EEG in order to get accurate measurements of brain activity during these events.