What is a CT scan?

A CT scan makes a three-dimensional (3D) picture of the inside of the body. The 3D picture is built up using lots of detailed x-rays taken by the CT scanner. 

  • It uses a small amount of radiation.
  • This is very unlikely to harm you.
  • It will not harm anyone you come into contact with.

Preparing for your scan

You will be given information about what you need to do before your scan. This will be things like:

  • You may be asked not to eat or drink for a few hours before the scan. This depends on the part of the body being scanned. If this is a problem for you, call the number on your appointment letter.
  • When you arrive at the hospital, you may be asked to put on a hospital gown.
  • You may be asked to remove any jewellery or objects containing metal, including:
  1. Piercings
  2. Hair clips
  3. Zips
  4. Bra
  • You may be asked to have a drink or an injection of a dye, this is called contrast. It helps show certain areas of the body more clearly. The contrast may make you feel hot all over for a few minutes. It is important to let your doctor know if you are allergic to iodine or have asthma. This is because you could have a more serious reaction to the injection.

Having a CT scan

You have the scan in the x-ray department at the hospital. The person who works the scanner is called a radiographer. The scan takes 5 to 10 minutes, but you may be in the department for longer. You lie very still on a narrow bed.

The bed moves slowly back and forward through the doughnut-shaped machine.You will probably be able to go home as soon as the scan is over. The radiographer may suggest you drink plenty of water for the rest of the day. This will help flush out the dye (contrast).

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