These scans create images of the inside of your body and provide different types of information. Your doctors will recommend the most useful scans for your situation. Ask your doctor or imaging centre what you will have to pay and whether Medicare covers the cost.
Before having scans, tell the doctor if you have any allergies or have had a reaction to dyes during previous scans. You should also let them know if you have diabetes or kidney disease, or are pregnant or breastfeeding.
Learn more about the imaging tests below:
X-ray
| How it works | Uses low-energy beams of radiation to create images of parts of the body, such as bones and the chest |
| How long | 10-30 minutes |
| What happens | You hold still in front of or on a machine while the images are taken; you might be injected with a dye (contrast) to improve the image |
| Special notes | Painless; the small dose of radiation will not make you give off radiation |
Mammogram
| How it works | Uses a low-dose x-ray to create an image of the inside of the breast |
| How long | 10-30 minutes |
| What happens | Your breast is placed between 2 x-ray plates, which press together firmly to spread the breast tissue |
| Special notes | Can be uncomfortable |
Ultrasound
| How it works | Uses soundwaves that echo when they meet something solid, such as an organ or tumour; a computer turns the soundwaves into a picture of the inside of the body |
| How long | 10-20 minutes |
| What happens | A cool gel is spread on your skin and a handheld device called a transducer sends out the soundwaves as it is moved across the area; some transducers are wands that can be inserted in a body cavity |
| Special notes | Usually painless, but can be uncomfortable |
CT scan (computerised tomography scan)
| How it works | Uses x-ray beams and a computer to create detailed pictures of the inside of the body, the scanner is large and round like a doughnut |
| How long | Up to 30 minutes |
| What happens | Before the scan, you may be given a drink or injected with a dye (contrast) to make the pictures clearer; you lie still on a table that moves in and out of the scanner |
| Special notes | Painless; the dye may make you feel hot all over and leave a bitter taste in your mouth |
PET–CT scan (positron emission tomography scan with CT scan)
| How it works | Uses a low-dose radioactive solution to measure cell activity in different parts of the body; when combined with a CT scan it provides more detailed information about the cancer. |
| How long | About 2 hours |
| What happens | You are injected in the arm with a small amount of radioactive solution, wait 30–90 minutes for it to move through your body, and then have the scan; cancer cells take up more of the solution than normal cells do and light up on the scan |
| Special notes | The solution leaves your body in urine after a few hours; you may be told to avoid children and pregnant women for a number of hours |
Bone scan
| How it works | Uses radioactive dye to show any abnormal bone growth |
| How long | Several hours |
| What happens | You are injected in the arm with a small amount of radioactive dye, wait 2–3 hours for it to move through your bloodstream to the bones, then your body is scanned; a larger amount of dye will usually show up in any areas of bone with cancer cells |
| Special notes | The dye leaves your body in urine after a few hours; you may be told to avoid children and pregnant women for a number of hours |
MRI scan (magnetic resonance imaging scan)
| How it works | Uses a magnet and radio waves to take detailed pictures of an area of the body |
| How long | 30-90 minutes |
| What happens | Dye (contrast) may be injected into a vein to make the images clearer; you lie on a table that slides into a narrow metal cylinder that is open at both ends; the scan is noisy, so you will often be given earplugs or headphones |
| Special notes | Let the medical team know if you feel anxious, you may be given medicine to help you relax; people with some pacemakers or other metallic objects cannot have an MRI |
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Prof Chris Karapetis, Network Clinical Director (Cancer Services), Southern Adelaide Local Health Network, Head, Department of Medical Oncology, and Director, Clinical Research in Medical Oncology, Flinders Medical Centre and Flinders University, SA; Dr Amey Aurangabadkar, Radiologist, Illawarra Radiology Group, NSW; Clare Brophy, Consumer; Prof Katherine Clark, Clinical Director of Palliative Care, NSLHD Supportive and Palliative Care Network, Northern Sydney Cancer Centre, Royal North Shore Hospital, NSW; Prof Wendy Cooper, Senior Staff Specialist, Tissue Pathology and Diagnostic Oncology, NSW Health Pathology, Royal Prince Alfred Hospital, NSW; A/Prof Richard Gallagher, Head and Neck Surgeon, Director of Cancer Services and Head and Neck Cancer Services, St Vincent’s Health Network, NSW; Dr Chloe Georgiou, Oncology Research Fellow, Australian Rare Cancer Portal, and Oncology Trials Fellow, Bendigo Health Cancer Centre, VIC; Dr Susan Harden, Radiation Oncologist, Peter MacCallum Cancer Centre, VIC; Justin Hargreaves, Medical Oncology Nurse Practitioner, Bendigo Health Cancer Centre, VIC; Dr Laura Kirsten, Principal Clinical Psychologist, Nepean Cancer Care Centre, NSW; Prof Linda Mileshkin, Medical Oncologist, Peter MacCallum Cancer Centre, VIC; Caitriona Nienaber, 13 11 20 Consultant, Cancer Council WA.
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