Neurophysiology Lab

The Neurophysiology Lab provides diagnostic neurophysiological testing for children and youth. This includes a wide range of tests like:

EEG
Evoked potentials
Electromyography and nerve conduction studies

How to make an appointment

We accept referrals from family physicians or pediatricians.

Fill out the neurophysiology lab's referral form

When submitting your referral, please include:

a detailed clinical description with current medication
any information or data if patient has had the same test done elsewhere
if an interpreter is required and for which language (if language is other than English or French)

Mail or fax the referral form to:

Neurophysiology Lab (C-A)
CHEO
401 Smyth Road
Ottawa, ON K1H 8L1

Fax: Lab 613-738-4879

Scheduling centre 613-738-4865

What happens next

Once the referral has been received, reviewed and triaged, an appointment will be booked. The patient will be notified directly with their appointment time.

Make sure to let CHEO know if the status of the patient changes.

About your appointment

Neurophysiology Lab is located in C-A (Garry Cardiff Wing, level 1 - basement). You will need to bring the following items to your appointment:

health card
any medications

EEG: Electro-encephalograms

What is an EEG?

An EEG records "brain waves" on a computer. It doesn't hurt, and has no side effects. It gives us information about brain activity, and can help us decide if there is a problem. We also use EEGs to monitor children and youth with brain conditions like seizures. It usually takes about an hour.

How do we prepare our child for the EEG?

On the morning of the test, wash your child's hair. Don't use gel, mousse or hairspray. Your child can eat as usual, but should not have anything with caffeine in it (like Coke, Pepsi, coffee, tea or energy drinks). Make sure your child uses the washroom before you come into the lab.

What about medications?

Give your child or youth all prescribed medications on the day of the EEG, unless your doctor tells you not to.

Sleeping and napping instructions

Routine EEG (4-18 years)

Sleep and nap as usual.

Routine and sleep deprived EEG (0-3 years)

Morning appointment: no morning nap. No nap during the drive to CHEO. Feed your child as usual.
Afternoon appointment: if your child has a morning nap, don't let your child sleep for more than 20 minutes. No afternoon nap or sleeping during the drive to CHEO.

Sleep deprived EEG

We will record brain activity while your child sleeps. Bring anything that usually helps your child to fall asleep.

3-5 years: put your child to bed 2 hours later than usual, and wake your child at 5 am. No nap during the drive to CHEO.
6-18 years: have your child or youth go to bed 2 hours later than usual, and wake your child at 4 am. No nap during the drive to CHEO.

Prolonged EEG

This will record events not captured in the routine EEG. Your child can sleep and nap as usual. We will give your child lunch.

Ambulatory EEG

This is a portable EEG that you'll take home with you in a small backpack to record any seizures. Your child should carry on with everyday activities. You'll come back the next day to remove the disks and wires. Your child can sleep and nap as usual.

What will happen during the EEG?

For the EEG:

Your child or teen will rest quietly on a bed.
We will measure your child's head, and then stick small disks to your child's head using a soft paste. We attach these disks (electrodes) to the EEG computer to record brain activity. No needles are used.
We will video tape your child during the EEG, so we can match his brain activity to any movements he makes.
If your child is old enough, we'll ask her to open and close her eyes and take some deep breaths. We may also have your child look at some bright lights.
Your child can bring a favourite toy or blanket and wear comfortable clothing.

What happens after the EEG?

Please don't drive if you have stayed awake with your child for a sleep deprived EEG. Arrange for a safe ride home. Your child's hair may have some leftover paste in it. You can remove this easily with a damp washcloth. Results are usually ready in about 2 weeks.

EMG: Electro-myogram

What is an EMG?

An EMG has 2 parts:

Nerve Conduction Studies (NCS) to check the way nerves carry electrical signals.
EMG (electro-myogram) to check muscles. Doctors only do this part if it is needed.

How do we prepare our child for the EMG?

Make sure your child or teen has a bath or shower the morning of the EMG.

What will happen during the EMG?

Nerve Conduction Studies (NCS)

This may be the only part that your child or teen needs. This test does not cause any health risks. It will take about an hour. For this part of the test, we will:

Tape special wires to the skin
Stimulate the nerve we are testing with a quick, electrical shock. This feels like the shock you sometimes get when you touch a door knob after walking on a carpet.

EMG (may not be needed)

The doctor will use a very thin needle to check the muscles we want to know about. The needle is a lot like the ones used for acupuncture (much smaller than needles used for blood tests). With this test:

There will be some mild discomfort when the needle is placed-it will feel like a mosquito bite.
The needle will stay in place for 10-30 seconds to pick up any problems with the electrical signals in the muscle.
The number of muscles checked depends on your child or teen's medical problem.
Children or teens with bleeding disorders have a risk of bleeding.

How do we get the test results?

After the tests, we will review the results and send them to the doctor who ordered the EMG. It usually takes about 2 weeks for your doctor to get the results. Please don't call our lab for results. Your doctor will share the results with you. If your neurologist is in the lab during the test, he or she will talk with you about the test results right after the tests are finished. If you would like us to send the results to another doctor, you can go to our Health Records department and sign a release form.

Evoked Potentials (EPs)

What is an Evoked Potentials (EPs) test?

EPs test the nerve pathways in the spinal cord and brain. We test 3 types of EPs:

Visual Evoked Potential (VER): checks nerve pathways from the eyes.
Brainstem Auditory Evoked Potential (BAER): checks nerve pathways from the ears.
Somato-sensory Evoked Potential (SSEP): checks pathways from the arms and legs.

During EP testing, we send quick signals to a nerve, and use a special computer to record the brain's response.

How do we prepare our child for this test?

Children and youth need to lie very still for about an hour during this test. If you feel your child will not be able to lie still for that long, let your doctor know. Children sometimes need to be admitted to our day surgery unit so that they can have the test under sedation (special sleep medication).

Please wash your child's hair the day before the test. Do not use gel, mousse, hairspray or oil.

What will happen during the Evoked Potentials test?

For this test, we will stick wires on your child's head, neck and back with a soft, washable paste. We do not use any needles or radiation, and there are no side effects. Your child will need to lie very still during this test.

Visual EPs

Babies and some children: will wear special goggles that show flashing lights.
Older children: will look at checkerboard squares that switch back and forth from black to white on a TV screen.

Auditory EPs

For this test, your child will listen to clicking sounds through earphones.

Sensory EPs

For this test, we will stimulate the nerve we are testing with a quick, electrical shock. This feels like the shock you sometimes get when you touch a door knob after walking on a carpet.

How do we get the test results?

After the tests, we will review the results and send them to the doctor who ordered the EP test. It usually takes about 2 weeks for your doctor to get the results. Your doctor will share the results with you; please don't call our lab for results. If you would like us to send the results to another doctor, you can go to our Health Records department and sign a release form.

Need more information?

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