Magnetic resonance imaging

What is magnetic resonance imaging?

MRI uses a large magnet, radio waves and a computer to produce detailed images of organs and structures within the body. Unlike X-rays and CT scans, MRI does not use radiation. There are no known harmful effects from having an MRI scan.

An MRI is often used to:

• Look at the heart, brain, liver, pancreas, reproductive organs and other soft tissues.
• Assess blood flow.
• Look for tumors and find many forms of cancer.
• Look at infections.
• Assess injuries to bones and joints.

What happens during the MRI scan?

When it is time for the scan, the nurse or technologist will take your child to the room where the MRI scanner is kept. You can stay with your child during the scan. The MRI scanner uses a magnet so you and your child will need to take off any metal that you are wearing (belts, jewelry, earrings and watches, etc.). Most braces and fillings in teeth will not be a problem.

Your child will lie down on a special table in the scanning room. Your child must lie very still during the scan. If it is hard for your child to hold still, medicine may be given to help your child feel sleepy (sedation).

When your child is comfortable, the table will move slowly inside of the scanner. The MRI scanner is noisy. Your child may go into the scanner head first or feet first. Your child will not feel anything unusual during the scan. The technologist and nurse will use a TV camera to watch your child and a microphone to talk to your child. The test should take between 30 and 90 minutes.

Your doctor will get the results of the test within three days and will share the results with you and your family.

A special note to parents

If you wish to stay with your child during the MRI scan, you must meet safety guidelines. For example, you must not have metal surgical clips, a pacemaker or be pregnant. The nurse or technologist will discuss these precautions with you.

How should my child prepare?

• It is important for your child to lie very still for the MRI scan. If you child does not feel well, it may be hard to lie still. If your child has a cold or is sick on the day of the appointment, please call the MRI Department at (414) 266-3180. Your child's appointment may need to be changed to another day.

• If it is hard for your child to lie still, a nurse may need to give your child medicine to make him or her sleepy (sedation). Most young children will need sedation for an MRI scan. To keep your child safe during the sedation, do not let your child eat or drink anything before the MRI scan. Use the guide below which is based on age:

0-5 months old:

• No food, milk, formula or breast milk four hours before the scan.
• May have clear liquids from two to four hours before the scan. Clear liquids include apple juice, water or Pedialyte.
• Nothing to eat or drink two hours before the scan.

6 months and older:

• No food, milk, formula or breast milk six hours before the scan.
• May have clear liquids from two to four hours before the scan. Clear liquids include apple juice, water, white soda, Pedialyte, popsicles, clear broth, Gatorade and Jell-O without fruit.
• Nothing to eat or drink two hours before the scan.

If the above feeding instructions are not followed and your child needs sedation, the scan will need to be done on another day. If your child has diabetes or is taking medicine, check with your doctor about these instructions.

There is a chance that your child will need to receive sedation or contrast through an IV. Please prepare him or her for this possibility.

There may be times when, even with sedation, a child is not able to lie still long enough for the scan to be done. If this happens, the test will need to be done on another day.

Special precautions

If your child was given sedation, he or she will be able to leave the hospital a short time after waking up. He or she may still feel sleepy or dizzy for a few hours after the scan. Have your child stay home and rest for the day. Your child may play quiet games, but should not do activities such as riding a bike or climbing.

Learn more about MRI.

Visit our teaching sheets page to learn more about your child's test.