What is a CT scan?
CT, or Computed Tomography, uses X-rays to produce detailed three-dimensional images of any part of the body.
What happens during my CT scan?
You will be asked to lay on a table, which will move in and out of the donut-shaped scanner while the images are being taken. You may hear a soft “whooshing” sound as the x-ray camera spins around the scanner, but it is not loud. You may be asked to hold your breath a few times for about 5 seconds.
Certain scans require an injection of IV contrast, also known as “X-ray dye”. This is an Iodine-based liquid that is injected through a small needle in a vein, and improves our ability to make an accurate diagnosis. Most patients experience a hot flush for about one minute while the dye is being injected, but this soon passes.
Most CT scans take about 10 minutes.
What are the risks vs benefits of having a CT scan?
Your doctor may prefer a CT scan over other modalities such as X-ray or Ultrasound because the image detail is much higher, which allows for a more confident diagnosis.
The radiation levels for CT scans, while still relatively low, are higher than X-ray levels and therefore carries more risk. There is no conclusive evidence that the radiation levels used in a single CT scan cause long term health issues, however we always try to limit the amount of radiation a patient receives over their lifetime.
In the vast majority of cases, the benefits of having a CT scan (such as your doctor making an accurate diagnosis) greatly outweigh any potential risks.
If you are pregnant, or think you may be pregnant, it is essential that you let our staff know before you have your scan.
Preparation for a CT scan
Scans that need IV contrast require you to keep well hydrated and eat nothing for 2 hours before your appointment. We may also require some recent blood test results to check your kidney function. If you are diabetic or have a history of kidney disease, please let the receptionist know at the time of booking.
Scans that do not require IV contrast generally have no specific preparation.
The receptionist will inform you of the appropriate preparation at the time of booking.