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What is a CT Pulmonary Angiogram?
A CT pulmonary angiogram (CTPA) is a test using a small amount of radiation (X-rays) to test if there are any blood clots in your lungs. A blood clot in the lungs is known as a pulmonary embolism; this can be very serious and potentially life-threatening.
Is it safe to be exposed to X-rays while I’m pregnant?
If your referring doctor finds you need a CT scan for a medical problem, they will weigh up the benefit to you versus the risk to your baby.
What are X-rays?
X-rays are a form of radiation. This kind of radiation is invisible. CT uses X-rays to make images of bones and organs in your body. They have been associated with a very small increased risk of cancer, particularly leukaemia, for an unborn baby. But the risk is very small.
Do all types of examinations have the same amount of radiation?
No. Different types of examinations expose you to different levels of radiation. Your referring doctor will take this into account, and the examination with the smallest dose of radiation will be chosen.
What are the risks involved?
Any CT scan involving exposure to radiation comes with the potential of a slightly increased risk of cancer over the course of a lifetime. This risk increases with the radiation dose; however, this needsto be compared with the natural risk of cancer. According to the Royal Australian and New ZealandCollege of Radiologists (RANZCR, 2017), the average natural risk of childhood cancer is approximately 1 in 500 (0.2%) so the risk of childhood cancer from a CTPA scan is much lower(0.001% to 0.0001%).
Could I have another test instead of CT scan?
Your referring doctor may suggest a Nuclear Medicine scan called a V/Q scan. This scan also uses radiation and the risk from radiation exposure is comparable to the CT Pulmonary Angiogram.
Ultrasound and MRI are not suitable examinations to investigate for pulmonary embolism.
I still have questions; who can I ask?
Medical information can be complex, and you may receive information that you do not fully understand. Please feel free to talk to your referring doctor or the radiographer performing the CT scan about any questions or concerns that you have. You can take this information sheet with you.
