A CT (computerised tomography) scan uses x-rays to build a three-dimensional picture of the inside of the body. You may be given either a drink or injection of dye.

What is a CT scan?

A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body. The scan takes 10 to 30 minutes and is painless.

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

You may be given a drink or injection of a dye, which allows particular areas to be seen more clearly. This 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, because you could have a more serious reaction to the injection.

You will probably be able to go home as soon as the scan is over.

Types of CT scan

There are some specialised types of CT scan:

  • CT urogram
  • spiral CT scan
  • virtual colonoscopy (CT colonography).

You can read more about specialised types of CT scan in the information about your type of cancer.

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