• Patient should fast for about four hours if intravenous contrast (a medication that enhances and better define blood vessels and accentuate the appearance between normal and abnormal tissue in organs) injection is required.
• Please inform staff if you have any history of allergies.
• Please be punctual for your appointment.

• You will be asked if you have any history of allergies or poor kidney functions.
• Informed consent will be obtained if intravenous contrast is required.
• If the CT is to examine your abdomen, you will be asked to swallow a liquid contrast material that will enable better visualisation of the stomach and bowels. It may be necessary for you to wait while the contrast material reaches the bowels. If the lower bowels are to be studied, we may require administering contrast material by enema.
• An intravenous injection line may be set up in preparation of the intravenous injection.
• You will be positioned on a padded table and moved into the scanner.
• The radiographer will be able to see and hear you at all times.
• You will be intermittently asked to stop breathing. It is important to follow the instructions given in order to ensure that the examination is successful.
• If the intravenous injection is given, a warm sensation will be felt as the injection goes through the body. Some people report feeling a flush of heat or a metallic taste at the back of the mouth. These sensations usually disappear within a minute or two.

BENEFITS

• Unlike other imaging methods, CT scanning offers detailed views of many types of tissue, including the lungs, bones, soft tissues and blood vessels.
• CT scanning is painless, non-invasive and accurate.
• CT examinations are fast and simple. For example, in emergency cases, they can reveal internal injuries and bleeding quickly enough to help save lives.
• CT scanning can identity both normal and abnormal structures, making it a useful tool to guide radiotherapy, needle biopsies and other minimally invasive procedures.
• CT has been shown to be a cost-effective imaging tool for a wide range of clinical problems.

RISKS

• The effective radiation dose from this procedure ranges from 1 mSv - 14 mSv, depending on the body region scanned. For reference, the annual background radiation dose that a person receives is about 3 mSv. 

• Cancer risk from radiation used in diagnostic imaging is so small that it can't be reliably quantified. In addition, our x-ray equipment and protocols have been optimised in such ways that the radiation dose is kept to as low as reasonably achievable, without sacrificing diagnostic quality of the image. 

• Women should always inform the radiographer if there is any possibility that they are pregnant.

• ACR and RSNA Radiology Info