Radioactive Tracer
Contents
Key Stage 4
Meaning
A radioactive tracer is an unstable isotope which is injected into a patient to trace the flow of fluids around the body.
About Radioactive Tracers
- In radioactive tracers the unstable isotope is part of a compound.
- Radioactive tracers can be used to image specific glands, organs or trace the flow of fluids through the body.
- Radioactive tracers are usually gamma-ray emitters because Gamma-rays can penetrate most materials so most of the gamma-rays leave the body without being reflected, refracted or absorbed by the tissue.
- Different glands and organs collect different compounds from the blood stream. A compound containing a radioactive isotope can be injected into the blood and this will accumulate in the desired gland or organ. While there the unstable isotopes decay and this can be detected. This can be used to create an image of that gland or organ.
- Fluids in certain organs can become blocked. These blockages can be detected by injecting or ingesting a radioactive isotope which will accumulate at the blockage. This accumulation can then be detected as the unstable isotopes decays to produce ionising radiation.