- Cancer Information
- Cancer treatment
- Radiation therapy
- External beam radiation therapy (EBRT)
- Imaging scans you may have
Imaging scans you may have
During planning and treatment, you may need to have some of the following tests to show the exact position and shape of the cancer. Your treatment team will explain what to expect from each test, or you can call Cancer Council 13 11 20 for more information.
Intense but low-energy radiation passes through the body and creates an image on x-ray film, with black areas representing soft tissues and lighter areas showing denser tissues, such as bones.
A CT (computerised tomography) scan uses x-ray beams to create detailed pictures of the inside of the body. Before the scan, you may have an injection of dye into one of your veins to make the pictures clearer. You will lie on a table that moves slowly through the CT scanner.
An MRI (magnetic resonance imaging) scan uses a powerful magnet and radio waves to create detailed cross-sectional pictures of the inside of the body. A dye may be injected into a vein before the scan to make the pictures clearer. You will lie on a table that slides into a large metal tube. The machine can be quite noisy.
Before a PET (positron emission tomography) scan, you will be injected with a solution containing a small amount of radioactive material. Cancer cells absorb more of the solution and show up brighter on the scan.
This combines a PET scan and a CT scan in one machine. The machine looks similar to a CT scanner.
An ultrasound uses soundwaves to create pictures of your internal organs. A small device called a transducer is passed over an area of the body. The transducer sends out soundwaves that echo when they meet something dense, like an organ or tumour.
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.
Download a PDF booklet on this topic.
Dr Madhavi Chilkuri, Radiation Oncologist, Townsville Cancer Centre, The Townsville Hospital, and Dean, RANZCR Faculty of Radiation Oncology, QLD; Polly Baldwin, 13 11 20 Consultant, Cancer Council SA; Patricia Hanley, Consumer; Prof Michael Hofman, Nuclear Medicine and Molecular Imaging Physician, Peter MacCallum Cancer Centre, VIC; Leanne Hoy, Cancer Nurse Consultant, GenesisCare, VIC; Sharon King, Accredited Practising Dietitian, TAS; Dr Yoo Young (Dominique) Lee, Radiation Oncology Consultant, Princess Alexandra Hospital, QLD; Dr Wendy Phillips, Senior Medical Physicist, Department of Radiation Oncology, Royal Adelaide Hospital, SA; Katrina Rech, Radiation Therapist and Quality Systems Manager, GenesisCare, SA. We also thank the health professionals, consumers and editorial teams who have worked on previous editions of this title.
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