Ambulatory EEG (Electroencephalogram)
A. What is an Ambulatory EEG (aEEG)?
Ambulatory electroencephalography (aEEG) monitoring is an EEG that is recorded at home. It has the ability to record for up to 72 hours. The aEEG increases the chance of recording an event or abnormal changes in the brain wave patterns.
B. Why am I getting an an aEEG?
The aEEG is used to record abnormal brain activity that could not be recorded with the regular 20 minute EEG recording. If abnormal activity only happens a few times a day or during certain times of the day, the aEEG will be able to capture and record those events that would have been missed with the regular EEG. It can help a physician to diagnoses episodes or certain symptoms that are suspected to be due to seizures or capture electrographic seizures without symptoms (silent seizures).
This test can also be used if you continue to have seizures after trying different medications and to confirm or rule out the diagnosis of epilepsy.
C. How do I prepare for the test?
- Wash your hair the night before or the day of the test, but don't use any conditioners, hair creams, sprays or styling gels. Hair products can make it harder for the sticky patches that hold the electrodes to adhere to your scalp. If you have weaves or braids, they may need to be removed before a test can be completed.
- Wear a front opening shirt
- Take your usual medications unless instructed otherwise.
- Bring a list of medications with you to your appointment
D. How is the test performed?
You'll feel little or no discomfort during an aEEG. The electrodes will not transmit any sensations. They just record your brain waves.
Here are some things you can expect to happen during an aEEG:
- A technician measures your head and marks your scalp with a special pencil, to indicate where to attach the electrodes. Those spots on your scalp may be scrubbed with a gritty cream to improve the quality of the recording.
- A technician attaches flat metal 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 — makes bigger — the brain waves and records them on computer equipment.
Once the electrodes are in place, your head will be wrapped with gauze to help keep the elctrodes in place during your normal everyday activities.
The recorder device is attached to a strap that will go around your neck and the wires can be worn inside or outside of your clothing.
- Go about your normal daily routine except for showering. It is very important the equipment does not get wet, please keep all equipment away from water completely. Other than that, go about your normal day.
- During the test keep a written log of your events. The technologist will give you a log to keep track of any events or symptoms that are suspected to be result from seizures, "funny feelings" or anything you feel would be helpful for the doctor to know during the recording.
- During the 48-72 hours of recording you will need to change batteries in the recording device. A 24 hour study does not require battery change. The technologist will give you instructions on how the batteries are accessed and replaced in the equipment.
- Please return to the lab at your assigned time. The technologist will give you a specific time to bring back the equipment and be disconnected. Be sure to bring your log with you when you return the equipment. Failure to return the equipment on time and/or without the log will delay your results and will impact another patient scheduled to have the study using your equipment.
E. How do I get my results?
After the test, the technician removes the electrodes, your study will be downloaded to our secure server for the physician specially trained in EEG/Epilepsy to read. Results are generally available within a week after the test completion. The results will be sent to the physician that ordered the study.