PET - CT

What is a PET-CT scan?

A positron emission tomography (PET) scan is an imaging test that can help reveal how your tissues and organs are functioning. The PET scan uses very small, safe amounts of radioactive tracers and is used most frequently to detect and assess disease within the body. The PET images are fused with anatomical CT images to produce 3D images of your body. These images are viewed by a radiologist who produces a detailed report.

Understanding your PET-CT scan

Doctors may request that you have a PET-CT scan to see how well certain parts of your body are working, rather than simply showing what they look like.

A PET-CT is very helpful for investigating confirmed cases of cancer to determine how far the cancer has spread and how well it is responding to treatment. It is also helpful for detecting heart disorders, brain disease, and localise the source of pain in musculoskeletal disorders.

Before your PET-CT scan

When you make your appointment, we will let you know exactly what to expect for your scan and if there’s anything you need to do beforehand.

• Depending on your PET-CT scan, you might need to follow a personalised instruction sheet with the exact preparation you will need to do. You will receive this once your appointment has been booked.
• When having a PET-CT scan, you should allow 1.5-3 hours depending on the type of scan.
• As with conventional CT, you may be required to have an injection of x-ray contrast. There is a very small risk of allergy, and you will be asked about any previous allergic reactions before any injection is given.

On the day of your PET-CT scan

• Check in at reception.
• You will be taken to a private room where your technologist will explain the procedure and you can ask any questions you may have.
• You will be asked to change into a gown, and we will give you somewhere safe to keep your belongings.

During your PET-CT scan

18F-FBB PET-CT

This is a special type of PET scan which can detect Alzheimer's disease in its early stages.

• You will be taken into the scan room, positioned on the scanning bed, and given an injection of a radioactive tracer called 18F-FBB.
• You will have an initial 10-minute scan. It is important for you to keep still during the scan.
• After your initial scan you will be taken back to your private room, where you will be asked to rest for approximately 75 minutes. This is the uptake period when the tracer is absorbed by the brain. It’s a good idea to bring something to read.
• After the uptake period, you will have a second scan, this one for 20 minutes.
• The radioactive tracer used in this scan is produced in Melbourne, Australia on the day of your appointment. We rely on a same day international flight for delivery of the tracer. On rare occasions, delays or cancellations can occur and are outside of our control.

18F-PSMA Prostate PET-CT

This is a very sensitive test for identifying prostate cancer, even in the early stages of the disease.

• When having a PET-CT scan for prostate cancer, you will receive an injection of a radioactive tracer called 18F-PSMA. This tracer is absorbed by active prostate cancer cells.
• After the injection, you will relax for 2 hours while the tracer circulates around your body.
• During this 2-hour period, you will be encouraged to drink water and can empty your bladder as needed.
• This scan will take approximately 30 minutes.

18F-FDG PET-CT Brain

This PET-CT scan Is mainly used to assess treatment options in epilepsy. It is also very sensitive in detecting structural changes to the brain following head injuries.

• When having a PET-CT scan of the brain, you will receive an injection of a radioactive tracer called 18F-FDG. This is a radioactive sugar that is taken up by cells in the brain.
• The tracer is injected into a vein in your arm while you are lying on the scanner and takes approximately 45 minutes in total.
• Scans are taken during the first few minutes, then again after 30 minutes. You will need to rest quietly on the scanner bed in between scans.

18F-FDG PET-CT Whole Body

This is an imaging tool used to investigate the whole body, specifically in oncology (cancer).

• When having this PET-CT scan, you will receive an injection of a radioactive tracer called 18F-FDG. This is a radioactive sugar that is taken up in active tissues including many types of cancer.
• After this injection you will need to rest quietly for 60-90 minutes, while the radioactive sugar circulates around your body.
• As sugar naturally goes to muscles that are moving, to prevent these muscles from taking up the radioactive sugar and obscuring normal areas, you will need to lie quietly during the rest period.

18F-FET PET-CT

This PET-CT scan is used to assess brain tumours.

• This scan takes around 40 minutes.
• You will lie on the scanner bed and the radioactive tracer is injected into a vein on your arm.
• You will be made comfortable and asked to keep still for the duration of the scan.

18F-NaF PET-CT

This is an imaging tool that looks at your skeletal system. It can investigate any bones in your body, from your hand and wrist to your whole body in just one scan.

• For this scan, you will receive an injection of a radioactive tracer into a vein in your arm.
• After the injection you will be asked to rest for approximately 60 minutes to allow the tracer to be absorbed by your bones.
• The scan takes 10-45 minutes, depending on the part of the body being imaged.
• During the scan you may need an intravenous injection of x-ray contrast, which your technologist will discuss with you.

Please note: for some examinations, a urinary catheter is inserted into the bladder.

After your PET-CT Scan:

• You will need to stay and rest for a while. Once home, it is recommended that you should not be close to small children or pregnant women for four hours following your injection. This is because you will still have some radioactivity from the tracer in your body.
• If you need mild sedation for the PET-CT scan, it is essential to have someone to drive you home. You will not be able to operate machinery or drive a car for 12 hours following sedation.

Results

• The images taken during the examination are interpreted by one of our team of specialised radiologists.
• The results of your PET-CT scan will go to your referring doctor after a detailed report has been written.
• Your doctor will discuss the important findings and next steps with you.