MRI scan

An MRI scan uses strong magnetic fields and radio waves to make a picture of the inside of your body. The letters MRI stand for Magnetic Resonance Imaging. 

The MRI scanner at Great Ormond Street Hospital (GOSH) looks like a tunnel. As the scanner contains strong magnets, the doctors will need to check it is safe for you to have an MRI if you have any metalwork in your body (like a pacemaker or a brace on your teeth.) 

What happens

You'll have the MRI scan in the Radiology department. You have to lie very still for the MRI scan. Some young people may need some medicine that makes you feel really sleepy to help, but others can lie still enough without it. Sometimes, you might need an injection of dye to show up one bit of your body.

If you need an injection, your nurse will put some numbing cream or cold spray on your hand so you won't feel it so much. Your mum or dad will usually be able to stay with you during the scan.

Many of the studies we perform involve the use of x-rays. All girls aged 12 years or older are tested to make sure they are not pregnant on the day of their scan. If they are found to be pregnant the Radiology team will decide if the scan should be delayed or cancelled.

If you're having your head scanned, you'll need to wear a helmet, which goes around your head but doesn't touch it anywhere. When you go to the scanning room, you'll need to lie on a table, which will slowly slide into the scanner.

Once the table is inside the scanner, it won't move again until the scan is finished. When the scanner is taking the pictures, it makes loud banging noises but we'll give you some earplugs to muffle some of the noise.

You can also watch a video or listen to some music to take your mind off the noise.

When the scan is finished, the table will slide out of the scanner again and you'll be able to go home.

The scan may take between 20 minutes and an hour, depending on which part of your body is being scanned.

Does it hurt?

It will only hurt if you need to have an injection and this will only be a pin-prick.


The scan will be shown to a specialist to check. They will then write a report to your doctor. This might take a few days.

Compiled by:
Great Ormond Street Hospital
Last review date:
November 2016