Gallium scan

A gallium scan or gallium 67 scan is a type of nuclear medicine that uses a radioactive tracer to obtain images of a specific type of tissue, or disease state of tissue. Gallium salts like gallium citrate and gallium nitrate are used. The form of salt is not important, since it is the freely dissolved gallium ion Ga+3 which is active. For these applications, the radioactive isotope 67Ga is used. The body generally handles Ga+3 as though it were ferric, and thus it is bound (and concentrates) in areas of inflammation such as an infection site, and also areas of rapid cell division. This allows such sites to be imaged by nuclear scan techniques.

The gallium scan was the standard for cancer diagnosis and staging until it was replaced by positron emission tomography. It is still occasionally used to image inflammation and infection. After the tracer has been injected, images are taken 24, 48, and in some cases, 72, and 96 hours later. Each set of images takes 30-60 minutes, depending on the size of the area being imaged. The resulting image will have bright areas that collected large amounts of tracer, because inflammation is present or rapid cell division is occurring. A gallium scan is often used in conjunction with a computed tomography scan to overlay the areas of inflammation with organ systems.

Homeland Security

Crossing the U.S. border two weeks after a gallium 67 scan will alert the border guard to the presence of radioactive isotopes in your vehicle.