Fig - Placement of Sensors for an EEG

The electroencephalogram (EEG) is a medical test used to measure the electrical activity of the brain, via electrodes applied to your scalp. EEG can help diagnose a number of conditions, including epilepsy, sleep disorders and brain tumours. Another name for EEG is brain wave test.

Parts of the body involved: Scalp

Reasons for Procedure:
An EEG may be done for the following reasons:

• To diagnose epilepsy, seizure.
• To diagnose brain injury.

There are very few risks associated with this procedure. If you are prone to seizures, and need to discontinue medication for the test, you may be more likely to have a seizure.

Fig - Wall Monitor

Prior to Procedure:
Depending on the reason for your EEG, you may be given some of the following instructions:

• Stop taking medications, such as antidepressants, stimulants, or seizure control, at least 1-2 days before the test.
• Avoid caffeine the day before and the day of the test.
• Shampoo your hair and do not use hairspray or gel the day of the test.
• If you are having a sleep EEG, you may need to stay awake the night before the test. You should also arrange for a ride to and from the test.
• If you are prone to seizures, arrange for a ride to and from the test.

Anesthesia: None.

Description of the Procedure:
You sit or lie in a chair or cot. Electrodes are attached to your scalp with a special gel or paste. These electrodes record the brain's electrical activity and transmit impulses to an electroencephalograph, which magnifies them and records them as brain waves on moving strips of paper. You will be asked to close your eyes and be still for most of the test. However, depending on the reason for the test, you may also be asked to breathe deeply and rapidly for 3 minutes.

After Procedure:
The technician removes the electrodes. You will be advised about restarting any medications you may have stopped.

How long will it take? A standard EEG takes about an hour.

Will it hurt? No, an EEG is painless.

Possible Complications: None.