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Your child's MRI scan under general anaesthetic

The information on this page is aimed at parents and carers whose children have been asked to have an MRI scan under general anaesthetic.

Please see the MRI scan information if your child does not need to have anaesthetic and for an explanation of what an MRI scan is.

Changing or cancelling your appointment

Please tell us as soon as possible if you need to cancel or change your child's appointment so we can offer it to another patient. 

If you have any questions about your child's appointment and admission for the scan, please phone 020 7188 7188 extension 58360, Monday-Friday, 9am-5pm. Outside of these hours, please leave a message on the answerphone.

For any enquiries about a cardiac (heart) MRI please phone 020 7188 7188 extension 50863, Monday-Friday, 9am-5pm. Outside of these hours, please leave a message on the answerphone.

Before coming to the hospital

Please follow the preparation details in our information leaflet Your child's MRI scan under general anaesthetic (PDF 47Kb).

You and your child will be asked to attend a ward in the hospital for a 'pre anaesthetic assessment'. This may be on the day of the scan or a day before.  

Preparing for the scan

Before MRI scan

The nurses on the ward will give you an MRI safety checklist to fill in for your child.

The radiographer (member of the radiology team trained to carry out scans) will go through your child's safety questionnaire with you and answer any questions you have about the MRI scan.

Your child will need to change into a hospital gown on the ward as metal can spoil the pictures.

The MRI department will contact the ward when it is time for your child's scan.

You can stay with your child while they are given the anaesthetic in the anaesthetic room, which is next to the MRI scanner. Once asleep, your child will be taken into the scanner.  

During the scan

The scanner is a short tunnel and when the scanner is working, it makes a loud banging noise. We will give your child headphones to wear, to protect their ears while they are asleep.

You can listen to some of the noises a scanner makes. 

MRI sounds one

MRI sounds two

MRI sounds three

MRI sounds four

Will my child need an injection?

If we are scanning certain areas of your child's body, we may need to give them an injection of contrast dye. This shows up on the scan and gives us more detailed pictures, particularly of your child's blood vessels. 

Further information on this is given in the patient leaflet, Your child's MRI scan under general anaesthetic (PDF 47Kb).

How long will the scan take?

This depends on which part of your child's body is being scanned and the information that the doctor needs. 

The radiographer will tell you how long he/she expects your child's scan to take. The whole procedure can take one to two hours on average. 

After the scan

As soon as the scan is finished, your child will be taken to the recovery room. Here, specially trained recovery nurses will closely monitor your child. You will be taken to the recovery room as soon as your child starts to wake up. Your child will return to the ward for monitoring and discharge.

The pictures taken during the scan are carefully studied by the radiologist (doctor trained in reading MRI scans to diagnose and treat illnesses), who will produce a detailed report. This will be sent to the doctor who referred your child for the scan. The results should be available to you at your next clinic appointment. For more urgent problems they may be available sooner. 


For general enquiries call the MRI reception on 020 7188 9218.

For appointment enquiries please contact one of the below:

  • MRI appointments - 020 7188 7188 extension 58360
  • heart MRI appointments – 020 7188 7188 extension 50863

How to find us

Level 1 – Arctic (penguin and igloo zones)
Evelina London Children's Hospital
Westminster Bridge Road
London SE1 7EH

How to get to Evelina London

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