Information for Consumers - Consent to Procedure or Treatment

This article tells you about consenting for a procedure or treatment and possible risks of diagnostic imaging.

What is consent to a procedure or treatment?

Consent to a procedure or treatment is when you agree to have treatment or a diagnostic test after having the risks and benefits explained to you.

Your doctor is aware of the risks and benefits of these imaging procedures and should always balance the possible benefits of you having the test with the small risk. It is always appropriate for you to have the x-ray or scan if the chance of finding out if you have something wrong with you, and the best way to treat it outweighs the very small risk of the scan.

You do however have the right to refuse an examination and may do so if you wish. Some hospitals and imaging practices will need you to fill in a consent form before you have the procedure. Your doctor will discuss the benefits and risks with you and may give you information about the treatment.

What are the risks of having x-rays, CT scans and nuclear medicine scans?

Ionising radiation is used in x-rays, CT (Computed Tomography) scans and nuclear medicine scans including PET (Positron Emission Tomography).

Ionising radiation may cause damage to the cells in your body. This is usually very minor and does not cause any serious damage, however, large doses may cause the cells to become cancerous. A very low dose x-ray, such as a chest x-ray, has a tiny risk. CT scans, which use higher doses of x-rays, have a higher risk, although it is still a very small risk.

The amount of radioactive material used for nuclear medicine scans and PET scans is very small, however, the radiation can sometimes take as long as a few days to pass out of your body. The amount of radiation you receive from these scans is similar to what you receive from x-ray procedures.

Some procedures, including some CT scans have a long term risk of you dying from cancer at about 1 person out of 1000. Although this is very low compared to the risk that everyone has of dying from cancer (about 1 person out of 4), it is important you are aware of the benefits and risks of having these imaging procedures.

A special liquid called a dye or contrast is used for some x-rays and scans. This is sometimes used to make the pictures clearer and show the parts of your body in more detail. There

is a small chance you may have an allergic reaction to the dye. You may have nausea, sneezing, vomiting, itching, hives and dizziness. There is also a very low risk of an anaphylactic reaction which can cause shock. This is very rare with a risk of about 1 in 25,000 injections.

Imaging procedures involving ionising radiation are not usually recommended for pregnant women, but can be performed in an emergency.

Further information

For more detailed information, please access InsideRadiology at:

This is a resource produced especially for consumers by the Royal Australian and New Zealand College of Radiologists:

A guide to gathering information that you may need for making informed decisions is published by the Consumers' Health Council of Australia at:

If you would like to look at other relevant articles, please access the following:

Or access the Diagnostic Imaging Pathways website at:

Or if you have questions or require any further information please contact your doctor or speak to the staff where you are going to have your procedure.

Consumer participation

This information has been reviewed by representatives from the following groups:

  • Aboriginal people
  • People with disabilities
  • Seniors
  • CALD (Culturally and Linguistically Diverse)
  • The Health Consumers' Council


All feedback, comments and suggestions regarding consumer information at Diagnostic Imaging Pathways are welcome. Please click on Contact Us


This article is intended as general information only. The Diagnostic Imaging Pathways team and Radiology Across Borders will not accept any liability arising from its use. The information is kept as up-to-date and accurate as possible. Please be warned that it is always subject to change.


© Copyright 2023, Diagnostic Imaging Pathways. All Rights Reserved. The information contained on this web site is protected by copyright.

Date reviewed: July 2017

Date of next review: July 2019