What is an EEG (electroencephalogram)?
An EEG is a medical test used to measure the electrical activity of the brain. This test records brain wave patterns and is useful in assisting in the diagnosis of epilepsy (seizure disorders) and excluding mimics of seizures such as sleep and movement disorders.
Types of EEG:
Standard (Routine) EEG tests
Usually, a standard EEG test will be done at the clinic room. The appointment is scheduled for 40 minutes although in younger infants this may take slightly longer to set-up. This study is normally performed in the awake patient.
Sleep-deprived EEG tests
A sleep-deprived EEG test is done when a child has had less sleep than usual, the night before the study (‘sleep deprived’). When patients are sleep deprived, there is a higher chance that abnormal electrical activity (if present) will be detected. Before a sleep-deprived EEG test, school aged children (>5 years) will be asked to stay up as late as possible (3 hours past the normal bedtime) and to wake up at least 2 hours earlier than normal. Care should be taken and discussion with your doctor should occur if your sleep deprivation is a trigger for your child’s seizure. In that case, it may be possible just to wake your child up earlier than usual on the day of the EEG test.
Overnight video-EEG study
This study is reserved for selected individuals with private health insurance coverage (criteria under overnight video-EEG checklist). This study requires admission to Norwest Private Hospital and the video EEG recording occurs overnight. This study is similar to a standard EEG expect that it records for more than 12 hours with the ability to capture sleep EEG features and record and sleep related events suspicious of a seizure.
Why does my child need an EEG?
The most common reason an EEG is performed is to assist in diagnosing epilepsy. It is useful also to exclude unusual movements in the awake and sleep state.
Is the EEG safe for my child?
The EEG test is painless and safe, without side effects. The electrodes only pick up the electrical signals that are present and do not affect the child’s brain or cause a seizure.
Younger children can be sensitive to having their head touched and bandaged (to keep the leads in place). Distraction and comfort from parents is helpful. Booking the study during a day nap of the child is helpful.