What is an electroencephalogram?
An electroencephalogram (EEG) is a test that measures the electrical activity in the brain, called brain waves. An EEG measures brain waves through small button electrodes that are placed on your child's scalp.
What steps should be taken to prepare my child for the 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. Do not wear hair extensions because they can interfere with the test.
To get the maximum information from this test, your child's doctor will try to record EEG during wakefulness and sleep.
Give your child his or her medications as usual. Bring a list of all the medications (dose and schedule) your child takes to the EEG Lab.
Your child's doctors will give you instructions about when your child can eat before and after the procedure.
Your child's doctor may suggest doing the test when your child in in a sleep-deprived state, requiring minimal sleep the night before the test.
On the day of the EEG, your child should not have any drinks containing caffeine, such as caffeinated sodas, coffee, and tea.
Who does the EEG?
A trained neurophysiology technologist performs the test.
How is the EEG done?
Your child will be asked to lie down on a bed or stretcher. The technologist will explain the procedure to you and your child. The EEG technologist measures your child's head and makes small marks on the scalp with a washable marker or pen. Each marked area is rubbed with a gritty lotion so the electrodes transmit well. Glue is put on the electrodes, which are applied to each of the marked spots on the scalp. The marking of the scalp and the application of the gritty lotion can be uncomfortable for some children. The electrodes are connected to the EEG machine and the test begins. Your child will need to sit or lie as still as possible. He or she may be asked to breathe fast (hyperventilate), look at flashing lights, and try to sleep. The test takes about one hour and your child is usually videotaped during the EEG. Your child's doctor may order a video EEG to give more time to study the brain waves. The procedure is the same, but may last 6 to 8 hours, or even overnight.
What happens after the EEG?
Once the test is complete, the electrodes will be removed and the glue washed off with warm water and a washcloth. Sometimes, all the glue will not come off and you may need to wash your child's hair at home.
The technologist or nurse will give you further instructions and tell you when you and your child may leave.
Are there any risks involved with the procedure?
Experts in neurology have studied EEG for many years and report that it is a safe procedure with no apparent risks.
Who evaluates the EEG recordings?
A neurologist will read the EEG and then talk to your child's doctor about the results.