Magnetic resonance imaging (MRI) is a type of scan used to diagnose health conditions that affect organs, tissue and bone.

MRI scanners use strong magnetic fields and radio waves to produce detailed images of the inside of the body. An MRI scanner is a large tube that contains a series of powerful magnets. You lie inside the tube during the scan.

An MRI scan can be used to investigate almost any part of the body including the:

  • brain and spinal cord
  • bones and joints
  • breasts
  • heart and blood vessels
  • internal organs, such as the lungs and liver


During an MRI scan, you lie on a flat bed which is moved into the scanning tube. Depending on the part of your body being scanned, you will be moved into the scanner either head first or feet first.

The MRI scanner is controlled by a computer which is in a different room from the scanner. This is to keep it away from the magnetic field generated by the scanner.

A radiographer will operate the computer. A radiographer is someone who is trained in carrying out X-rays and similar procedures. You will be able to talk to them through an intercom and they will be able to see you on a television monitor throughout the scan.

At certain times during the MRI scan, the scanner will make a loud clicking sound. This is the magnets being turned on and off. You will be given earplugs or headphones to wear.

It is very important that you keep still during your MRI scan. The scan will last between 15 and 90 minutes, depending on the size of the area being scanned and how many images are taken.