How is gamma radiation used in medical imaging?

Gamma radiation is used in medical imaging to detect and locate cancerous cells in the body.

Gamma radiation is a high-energy form of electromagnetic radiation that is emitted by radioactive isotopes. In medical imaging, gamma radiation is used in a technique called gamma imaging or scintigraphy. This involves injecting a small amount of a radioactive substance, called a radiopharmaceutical, into the patient's bloodstream. The radiopharmaceutical is designed to accumulate in specific organs or tissues in the body, depending on its chemical properties.

Once the radiopharmaceutical has accumulated in the target tissue, a gamma camera is used to detect the gamma radiation emitted by the radioactive isotopes. The gamma camera consists of a scintillation crystal, which converts the gamma radiation into visible light, and a photomultiplier tube, which detects the light and converts it into an electrical signal. The signals are then processed by a computer to produce an image of the target tissue.

Gamma imaging is particularly useful for detecting and locating cancerous cells in the body, as these cells often have a higher rate of metabolic activity than healthy cells. This means that they will accumulate more of the radiopharmaceutical, and emit more gamma radiation, than surrounding healthy tissue. Gamma imaging can also be used to detect other conditions, such as infections, inflammation, and blood clots.

Overall, gamma radiation is a valuable tool in medical imaging, allowing doctors to detect and diagnose a wide range of conditions with minimal invasiveness.