PET = Positron Emission Tomography - a unique type of scan that is used in a number of different medical conditions. A small quantity of a radioactive substance (a PET tracer) is injected into the patient and the PET scanner detects important information about a number of different illnesses.

There are only two dedicated PET scanners in NSW. The PET scanner at RPA has been in operation since 1992. Over this time more than 13,000 patients have been scanned, which is the largest PET experience in the country. In 2003 the SMU began to use PET tracers, made in our own cyclotron.

Recently a new PET- CT scanner was also installed - a first in Australia. This scanner combines the information from a 'CAT' scan with the metabolic data from the 'PET’ to provide even greater accuracy in diagnosis. This PET scan (see left) has identified deposits [arrowed] of secondary (metastatic) melanoma in the right chest and left body wall. The hot spot at the base of the image represents the accumulation of excreted isotope in the bladder. Reference

Important information for patients undergoing PET Scanning

Your Appointment: A staff member will call you to organise the scan date and time, and give you preparation details. It is important to tell the PET staff: Your height and weight  Your medications If you are diabetic If you are breastfeeding If you could be pregnant  If you are claustrophobic (frightened of small spaces) - although the PET-CT scanner is quite large and much less confining than an MR scanner.

RPA PET-CT Biograph DUO LSO Scanner

Location:

The PET-CT scanner is located on Level 7 of the Albert Pavilion at the Royal Prince Alfred Hospital, Missenden Road, Camperdown. It is 2 floors above the RPA Emergency Department which is located at street level on Level 5.

After entering the Hospital follow the signs to the PET and catch the elevator to Level 7. Parking is difficult around RPA but is available behind the old KGV Building, off Missenden Rd or at the RPA Medical Centre in Carillon Ave but this latter option is more expensive (see Map below).

Map of Royal Prince Alfred

CHECK LIST:

PREPARATION:
You should FAST (no food) for at least 5 hours prior to your appointment time, but you may drink water and take your usual medications (except for sedatives). If you are a diabetic you will receive special instructions.

Wear comfortable clothing because you will be lying or sitting for periods of time before and during the scan.

For some brain scans an EEG may be done before the PET scan - this allows us to check the electrical pattern of the brain which may influence the interpretation of the scan.

If you are booked for a heart scan, you will receive special instructions regarding what and when you should eat before the scan.

Preparation & Isotope Injection

A Nurse will take you to the preparation area and the Doctor will see you soon after. The procedure will be explained to you and any questions you have will be answered. You will then be asked to sign a consent form.

THEN the following routine is carried out.

• You will need to remove all metallic objects, eg jewellery, belts, bras etc because they interfere with the CT scan part of the study. We suggest you place any valuables into the lockers provided. Make sure you do not have any objects in your pockets (lying on keys in your back pocket can become very uncomfortable).
   
• A small cannula (small plastic tube) will be placed into a vein in your arm for the injection of the radioactive isotope (PET tracer). This may be a little uncomfortable initially but the staff are very experienced in this procedure and there are no long-term side effects from having a cannula for the scan. The radioactive isotope allows us to carry out the scan because the PET scanner is able to detect where the PET tracer goes. For brain scans a cannula will be placed in each arm; one for the injection and one to take three small blood samples. 
   
•  A technologist will give you the injection of the PET tracer through the cannula. This will not hurt and you will not experience any side effects. You may feel a slightly odd, cool sensation as fluid is injected into the vein. If you are having a brain PET scan your eyes and ears will be patched to reduce outside stimulation.

Scan & Duration

• After the injection you will rest quietly for another 50 minutes before you move to the PET-CT scanner. This period is called ‘the uptake period’. It is important during this period that you stay relaxed and comfortable. Anxious patients often subconsciously tense the muscles of the neck, back and shoulders, causing interference in the scan images. If you are anxious or uncomfortable please tell the staff so they can assist you. 
   
• After the uptake period you will be asked to empty your bladder before going onto the scanning bed. 
   
• When you get on the scanning bed it is important to position yourself so that you are as comfortable as possible. If you have a ‘bad back’ the staff can assist by placing support under your knees, so please let them know. 
   
• The scan duration will depend upon the type of study being done. For a whole body study the scan may take 20 minutes (it depends on how much of you we need to scan) but you will be told about this before you get onto the scanner. A brain PET scan only takes about 8 minutes. A special head rest will be used to hold your head straight and still for the scan. During the scan you need to remain still - the best way to do this is to ‘relax into’ the bed.
   
• There are microphones in the scanner so you can communicate with staff at any time. Music can be played while you have the scan for all studies except brain PET scans, so if you have a favourite CD or music that helps you relax, please bring it along and we will play it for you.

After the Scan and Results

• After the scan is finished the Nurse will remove the cannula(s) and you can help yourself to refreshments before you leave the Department. We encourage you to drink plenty of fluid after the scan to ‘flush out’ the radioactive material which is excreted through the kidneys. All the radioactivity will be gone by the evening of the scan.
   
• If you brought any X-ray films, please make sure that you ask the staff to return them to you as you leave.

The scan results are not available immediately because of the computer time needed to process the images, but your Referring Doctor will receive the report and images usually within one working day. For urgent studies, your Doctor will receive a verbal report on the day of the scan. We hope to soon be able to provide you with a CD that contains the study images for you to take when you leave.

If there are other Doctors that need copies of the results, please let the Secretaries, Nurses, Technologists or Medical Staff know before you leave the Department.