• Procedure takes 2-3 hours
  • Administers a radioactive tracer
  • You may need to fast before the test

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Everything you need to know about PET/CT

How PET/CT scans work

PET CT imaging uses a radioactive tracer called a positron emitter. A small amount of this tracer is injected into a patient's vein. Images are then taken to show the distribution of the tracer in the body. A PET/CT scanner looks similar to a CT scanner.

A PET/CT scan can be used to examine many pathologies, including:

  • Cancer
  • Infection / inflammation
  • Brain function

What to expect

A PET/CT scan is a safe, non-invasive imaging procedure.

On arrival, you may be asked to change into a gown. The technologist will take a brief medical history and explain the procedure. A cannula is inserted, usually at the elbow, and the radioactive tracer injected. You'll wait in the uptake room for 45-90 mins before entering the scanner room. There you'll lie on the scanner bed for 20-45 mins as images are taken. You may leave as soon as the scan is complete.

The day of the PET/CT Scan

6hrs prior to the scan
Start fasting (if required)

1 hour proior
Drink 2 glasses plain water

The PET/CT scan
2 - 3hrs procedure

After the scan
Time to go home

Request a PET/CT appointment

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What special diet is required for my PET/CT scan?

For most PET/CT scans you'll be asked to fast for 6 hours before you arrive. You'll be told this at the time of booking. It's important that no food, lozenges, chewing gum, liquid medications or drinks (other than plain water) are consumed during the fasting period. Plain water is permitted and we encourage you to be hydrated. If you're diabetic, please call us for specific instructions on when to take medication and when to start fasting. It's important to follow these instructions as some food and medication can change the distribution of the tracer in the body.

Can I take my medication on the day of the test?

Most medications can be taken as normal with plain water. Diabetic and liquid medications will need to be stopped for some PET/CT scans. If you take either of these, please mention it when booking so that specific instructions can be provided. Please bring a list of your medications to the appointment.

I have claustrophobia. Should I have the scan?

Most people who suffer from claustrophobia tolerate the scan well. You can bring an eye mask to wear during the scan if you prefer. Please discuss any concerns at the time of booking and we can arrange for you to view the scanner before your appointment date.

What should I wear for my scan?

You should wear comfortable clothes with no metal. You may be asked to change into a gown and remove jewellery prior to the scan.

Is the radiation harmful?

A PET/CT scan is considered a safe procedure. The radioactive tracer only remains in the body for a few hours. The radiation dose from this tracer is the same as several years of background radiation from the environment. You may be asked to avoid close contact with pregnant women and small children for a few hours after the scan. It's important that you tell us at the time of booking if you're pregnant, breastfeeding, or the primary/sole carer for small children so we can discuss special arrangements.

How will I feel after my scan?

There are no side effects from the test. You can safely drive, eat, and drink as normal afterwards. However, you may be asked to avoid close contact with pregnant women and small children for a few hours after the scan.

Meet Dr Peter Zheng

Consultant Radiologist, Lumus Imaging, Brisbane

"We are constantly adopting the latest technology and ideas, expanding into regional, rural and metropolitan areas, and attracting professionals with genuine talent and enthusiasm at every level. "

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