A positron emission tomography (PET) scan is an imaging test that can help reveal how your tissues and organs are functioning. A small amount of radioactive material is necessary to show this activity.

The precise type of radioactive material and its delivery method depend on which organ or tissue is being studied by the PET scan. The radioactive material may be injected into a vein, inhaled or swallowed.

More radioactive material accumulates in areas that have higher levels of chemical activity. This often corresponds to areas of disease and shows up as brighter spots on the PET scan. A PET scan is useful in evaluating a variety of conditions — including neurological problems, heart disease and cancer.

May. 07, 2011