Computerised Tomography (CT)

What is Computerised Tomography (CT)?

Computerised Tomography (CT) uses an X-Ray machine and advanced computer programs to create two and three dimensional images of your body. CT is an essential imaging modality which utilises the latest and most advanced medical technology to detect and diagnose a range of disorders of the entire body.

How do I prepare for my CT?

You will be informed of any special preparation required for your CT scan at the time of your booking.

The preparation can include fasting for two hours prior to examination, hydration and possible blood test, depending on the type of examination requested. Abdominal CT examinations may also require you to drink one litre of fluid prior to the appointment.

Metal objects such as watches, keys, coins and jewellery will show up on the CT affecting the images and therefore may need to be removed.

You may be provided with a gown to wear instead of your own clothes, as some materials and prints will show up on the CT.

What happens during a CT?

You will be asked to lie on a long table that will move through the doughnut shaped CT scanner. For the majority of CT examinations your head will remain outside of the machine. It is important to remain still and follow specific instructions that the High St Xray staff members will explain prior to the start of the scan. You may also be required to hold your breath at various stages throughout the examination.

For some CT scans it will be necessary to have a contrast liquid injected into your vein which will help show the area of interest more clearly and help the Radiologist to see how this part of the body is working.

Are there any after-effects from a CT?

There are no after-effects from a CT scan. You will be able to go about your normal activities immediately after your CT is completed.

How long does a CT take?

This depends on what examination you are having. The actual scan may only take a matter of seconds, but more time is allowed for positioning you on the CT couch, seeing to your comfort, and providing you with instructions before beginning the examination. On the whole, most examinations take no more than 5 – 20 minutes.

When the test is over, it may be necessary to wait while the images are reviewed by the High St Xray Radiologist to see if more are needed.

What are the risks of a CT?

Having a CT will expose your body to radiation. However at High St Xray all CT examinations are performed using the lowest radiation dose possible. The CT scanner at High St Xray utilises advanced dose saving technology to optimise low dose scanning techniques. No radiation remains in your body after the test.

If a contrast injection is required, it is important to tell your doctor and High St Xray staff if you have diabetes or kidney problems before your scan, as contrast may temporarily increase the load on kidney function whilst being excreted from your body. As with all drugs, there is a small risk of an allergic reaction to CT contrast. Even though these are extremely rare, they may range from a rash to facial swelling or breathing difficulties. Please let your doctor and High St Xray staff know if you have had any previous allergic reactions.

All female patients who are pregnant or may possibly be pregnant must inform High St Xray staff at time of booking as alternative medical imaging may be arranged.

For more information

Who does the CT report?

The person who operates the CT equipment is a Radiographer. The person who views the CT images and then interprets them and creates a diagnostic report is a Specialist Doctor called a Radiologist. The High St Xray Radiologist provides the written report to your referring practitioner, either electronically or via fax.

A Radiologist is a Medical Specialist who completes a formal Medical Degree followed by at least three years in general medicine practice before entering the five year Specialist training program. The Royal Australian and New Zealand College of Radiologists (RANZCR) conducts the Specialist training program and sets the professional standards for all Australian Radiologists.