Computed tomography (CT) is a fast and patient-friendly imaging procedure that uses X-rays to create cross-sectional pictures or ‘slices’ of your body. CT images are produced using X-ray technology and powerful computers.
You will be asked to remove jewellery and wear a hospital gown during the study, as all metal objects can interfere with image quality.
The contrast may affect kidney function, so depending on age and risk factors, you may be asked to undergo a blood test to assess kidney function before the CT scan.
Oral contrast is needed for certain examinations, which you need to start drinking 2-3 hours before the study. It is a special fluid usually diluted with water. IV contrast can also be administered while you are on the CT table. It is crucial to inform your referring doctor, radiologist, radiographer, or the receptionist if you are allergic to iodine, as the contrast is iodine-based. Depending on the severity of the allergy, anti-allergy tablets may need to be taken prior to the study, usually starting 12 hours before.
Another precaution that patients need to take before the administration of contrast dye is to inform the radiographer or radiologist of any kidney problems or known kidney diseases. The contrast may affect kidney function, so depending on age and risk factors, you may be asked to do a blood test to assess kidney function before the CT scan.
Make sure to follow any instructions before, during, or after the CT scan, such as drinking enough fluids to prevent dehydration and help the contrast to be removed from your system.
Like normal X-rays, CT scans are painless. Contrast administered through a vein may cause a slight burning sensation, a metallic taste in the mouth, and a warm flushing of the body. These sensations are normal and usually subside within a few seconds.
You will be asked to lie down on a narrow table that slides into the centre of the CT scanner.
Once inside the scanner, the machine’s rotating X-ray beam will cause some clicking and whirring noises. You must remain still during the examination as movement causes blurred images. Normal, relaxed breathing is allowed. Certain scans, such as chest CT, do require controlled breathing during parts of the scan.
Supporting pillows, cushions, or straps will be used to help you remain in position.
We are proud to have modern, top-of-the-range spiral CT scanners that allow scans to be performed in a single breath-hold. Generally, completing a scan only takes a few minutes.
We use a computer to process all the information received and create several cross-sectional imaging slices. These images can be viewed on a monitor, printed on film, or recorded onto a CD. Reconstructed images, in multiple planes, can be used to create 3D models of your body.
