As with all medical procedures, clinical radiology does involve a level of risk. However the benefit of improved diagnosis and early treatment are considered by medical experts to significantly outweigh any risks.

Being exposed to the radiation used in X-rays, whether in the form of plain radiography, CT scanning or fluoroscopy, carries with it a very small increase in the risk of developing cancer later in life. Sensitivity to the radiation depends on your age, with children being more sensitive than adults.

Specific imaging tests carry different risks.

CT (computed tomography) scans involve taking a series of X-rays from different angles which are computer processed to show cross-sections of the body. They use radiation and have a low level of risk. CT scans were previously known as CAT scans.

MRI (magnetic resonance imaging) scans use an external magnetic field to generate radio waves which are used to create images. The magnetic field only poses a safety risk if you have metal in your body such as pacemakers or hip joints that contain ferromagnetic materials. Unlike radiography and nuclear medicine, MRI does not use ionising radiation.

Nuclear medicine involves injecting, inhaling or swallowing a very small amount of radioactive medication called a radiopharmaceutical. A special camera is used to detect the radiation from the medication. There is a small degree of risk associated with the radiation and there can be a degree of risk from an allergic reaction, however this this is extremely rare. Talk to your referring doctor or radiologist if you have any concerns.

Ultrasound (sonography) uses high frequency sound waves to produce images. There are no known risks associated with ultrasound.

X-rays have been used for many years and are considered to be safe. Having an X-ray does exposes you to a small amount of radiation, the level depends on which part of your body is being examined, for example X-rays of your teeth will use less radiation than an X-ray of your spine.

Last saved on 13 October 2016.