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What is an MRI scan

Magnetic Resonance Imaging (MRI) is the latest and most advanced method of examining the body. It uses a combination of magnetism, low power radio waves and a very sophisticated computer. The resulting images are incredibly detailed, almost as good as opening the body up to 'have a look' but totally safe. The radiologist, a doctor trained to read the images, can help with diagnosis of the condition you are suffering from and also help estimate the extent or severity of a known condition.

How should you prepare for the scan?


Because it can take between 20 minutes to 1 hour to perform the scan, you have to allow plenty of time both before and afterwards. Don't plan a meeting soon after your given scan time as you might not make it! There are no child care facilities so don't bring the children! If you know your can't make the scan appointment please let the department know as it may be possible to offer your slot to another patient and the time isn't wasted!


MRI involves an extemely powerful magnet, so you don't want to take into the scanner anything that could be affected by the magnetism. It is easy to think of items such as credit cards with their magnetic strips but the you may have some internal 'metal' that you may have forgotten about. If you have any of the following then you are probably not suitable for the scan and must let the MRI department know.

  1. Cardiac pacemaker
  2. Cochlear implant (in your ear)
  3. Metal fragments in your eye
  4. Aneurysm clips in your brain
  5. Artificial heart valves

Whilst it is not a direct contra-indication are you pregnant ?

You may be asked to put on a gown, but you can come in a zipless tracksuit, pyjamas or something similar. A changing cubicle is available. It is preferable not to wear excessive amounts of hair spray , hair gel or eye make-up as they can interfere with some scans.

If you are genuinely claustrophobic then you may not be able to go into or even stay in the scanner. It is important that you let us know if this is the case and especially the MRI department. Some people once they have had time to become accustomed to the scanner will be able to go into it, but others just cannot. In this situation, sedation can be used but the alternative is a trip out of area to an 'open scanner', i.e. one that is not totally enclosed.


You will be asked to remove any metal objects from your body or clothing such as watches, jewellery, hair grips, coins, keys and credit cards. A locker may be provided but responsibility for absolute safety cannot be guaranteed. It may be better to leave as many of these items at home.

What happens during the scan?

The radiographer will position you on the moveable table which will slide you inot the scanner. It is absolutely critical that you are comfortable in the position that you are asked to lie in, because the time it takes to perform the scan may be as long as 40 minutes. During that time you have to keep as still as possible. So if you are not comfortable right at the start you certainly won't be after 20-30 minutes. If you have a lot of movement during the scan then it may affect the quality of the images obtained and reduce their accuracy. Make sure you are comfortable!

The scanner is far noisier than you might have expected, so you will need headphones, which are provided. You can listen to music but the key thing is to relax and 'chill-out'!

There is a 'panic' button to hold and the radiographer will be watching you during the procedure. If required it is possible for someone to be with you during the process.

For certain examinations it may necessary for an injection to be given at some stage during the procedure. It is important that you let the radiographer know if you have a needle phobia, before the imaging starts. Usually you should have been warned about the possibility at the start.

Where are the scanners?

MRI scanners are at the Royal Berkshire Hospital, at the West Berkshire Community Hospital and also at Circle Reading Hospital.

Further information can be obtained from the following link: The Royal College of Radiologists