What is medical radiation – and how are we exposed to it?
Some medical imaging tests and some types of cancer treatment use ionizing radiation. There are usually 2 ways you can be exposed to medical radiation:
Medical imaging tests
X-rays and CT scans (which are a series of x-ray images) use radiation to produce images of body organs to diagnose disease or injury.
During a PET scan, a low-dose radioactive sugar is injected into the body and picked up by a scanner that turns it into 3D images.
Radiation therapy (also known as radiotherapy)
Radiation for cancer treatment uses higher doses of radiation to destroy cancer cells. It works by damaging the cancer cells over and over again. The main use of radiation therapy is to shrink a tumour, but it can also be used in other ways to treat cancer. Radiation therapy is an effective treatment, but a side effect linked to radiation therapy in the past has been that you may be at greater risk of developing a second cancer years later.
Radiation therapy today is very sophisticated. It targets the tumour much more precisely using the least amount of radiation needed. This means there is usually less damage to nearby healthy cells and reduces the frequency and severity of side effects.