Electroencephalography (EEG)

  • An electroencephalogram (EEG, electro-en-kef-alo-gram) is a safe and pain-free test that records the electrical activity of the brain. The information is recorded on a computer and interpreted by a neurologist (a doctor specialising in disorders of the brain).

    Why does my child need an EEG?

    Your child's doctor may request an EEG to find out what's going on in the brain if your child has abnormal movements, seizures or sleep problems.

    What to expect with an EEG

    An EEG is not harmful. There are no X-rays or injections and there is no risk of electric shock. The electrodes just record brain activity. Some children may fear that the machine can read their thoughts or dreams, it is important to reassure your child that this does not occur.

    During setup, your child will not feel anything other than their scalp and hair being touched, and the procedure will not hurt at all.  There are no side effects from an EEG.

    Preparing for the EEG

    • Wash your child's hair the night before the EEG. They need to have clean, dry hair with no products applied (e.g.  oil, mousse or gel). Please make a new appointment if your child has lice as the test cannot go ahead.
    • If your child has recently had chicken pox, they must be must be completely better in order for the EEG to occur.
    • Ideally, your child will need to be fairly still during the recording. The EEG technologist is experienced in helping children of all ages to relax, and distractions such as toys and DVDs are encouraged. Younger children may benefit from dummies, bottles and other comforters, so remember to bring these to the appointment.
    • If your child has special needs or you think they may not be able to cooperate with the procedure, please contact the EEG staff to discuss your concerns and the best course of action.

    Before the EEG

    If your child has seizures during specific situations (e.g. during sleep) please speak to your doctor or the EEG staff about the implications for the EEG recording. It may be possible to provoke a seizure and record an EEG during the seizure episode, which is beneficial as this is when the most useful information can be found.

    Before testing, the EEG technologist will ask a few questions about your child even though you may have already given this information to your doctor.

    During the EEG

    You are welcome to stay in the recording room during the EEG if you wish. It is important to arrange for another adult to look after any other children while the recording is being done as they cannot stay in the room.

    • Your child will either sit in a reclining chair or be held by you.
    • After explaining the procedure, the technologist will measure your child's head and work out where electrodes (small metal discs) will be placed.
    • The technologist will clean these areas lightly before placing the electrodes (about 20 of them) on the scalp. The electrodes will be kept in place with a sticky paste and some light tape. The paste is easy to wash out of the hair after the test is completed.
    • After the electrodes have been placed, your child needs to remain reasonably still while the technologist sits at a computer, watching the screen.
    • Children old enough to cooperate will be asked to open and close their eyes during the recording. Later they will be asked to hyperventilate (do some deep breathing). The last part of the EEG test involves your child looking at a controlled flashing light. These try to stimulate the brain and bring on a seizure episode.

    A video is recorded in case a seizure episode occurs. This gives the neurologist an accurate visual record along with the EEG recording. If no events are recorded, the video is deleted.

    EEGs during sleep

    Sometimes doctors will request that an EEG is performed while a child is asleep.

    • If your child is young and still having morning or afternoon naps, skip the nap before the EEG.
    • If your child is older, you will be given instructions to follow when you make the appointment.

    Please do not let your child sleep on the way to your EEG appointment. Sedation is not used to help your child get to sleep for an EEG.

     Key points to remember

    • An EEG is completely safe and pain-free.
    • Your child needs to have clean, dry hair with no hair products.
    • Arrange for someone to mind other children, as they cannot be present for the EEG.
    • Your child needs to remain reasonably still during the test.
    • If sleep recording is required, follow the instructions you are given and do not let your child sleep on the way to the EEG.

    For more information

    Common questions our doctors are asked

    How long will the EEG take?

    The test usually takes about an hour, but sometimes it may take longer, especially if a sleep recording is needed.

    Are there any risks associated with EEGs?

    EEGs are very safe. The electrodes record activity – they don't stimulate the nerves or send any electricity into the brain, so there is no risk of getting an electric shock. EEGs don't involve X-rays or pain. If stimulated, an EEG can cause a seizure in a child who has a seizure disorder, but the experienced staff know what to do in these circumstances. Talk to your doctor about any risks associated with EEGs and any concerns you have.

    When will I receive the results?

    The EEG technologist cannot tell you the results, and administration staff will not provide results over the telephone. You must make arrangements with your doctor to receive the results. Please allow at least one week. In urgent situations, your doctor may obtain a preliminary report by telephoning one of our neurologists.


    Developed by The Royal Children's Hospital Neurology department. We acknowledge the input of RCH consumers and carers.

    Reviewed July 2018.

    This information is awaiting routine review. Please always seek the most recent advice from a registered and practising clinician.

    Kids Health Info is supported by The Royal Children’s Hospital Foundation. To donate, visit www.rchfoundation.org.au.


Disclaimer  

This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.