CT Scans - FAQ


Written by Dr Joy Yip - BSc (Med) MBBS (UNSW) MPH (USYD)

What does CT stand for?

CT stands for computerised tomography or computed tomography. This technology has been used in medical imaging since the 1970’s and involves taking a large series of x-rays and using a computer to piece the information together. The term “CAT” scan stands for computed axial tomography and refers to the same process but is outdated as scans can now be taken in multiple dimensions and not just 'axial'.

How much radiation is there from a CT?

Having a CT scan will expose a person to ionising radiation. This has the potential to cause cancer. The amount of radiation from a CT scan differs according to what part of the body is being scanned and the age of the scanner. Newer machines are able to take better quality images with less radiation. For example: a CT head results in a radiation dose of 2.2 mSv which is roughly the same as 110 basic chest X-rays or 9 months of natural exposure to background radiation.

How long does a CT scan take?

The scan itself takes under 10 minutes but the total time involved is around half an hour to an hour. Patients requiring images of multiple parts of the body or contrast injections will have a longer procedure time.

How much does a CT scan cost in Australia?

This will vary depending on what part of the body is being scanned. If you have a valid referral from a GP you should be able to claim part of this from Medicare. These days, some practices offer bulk billing for CT scans. If bulk billing is not offered, you may be out of pocket around $50 to $300.