The gamma camera, also known as a scintillation camera or as an Anger camera, is one that detects and images the effects of radioisotopes emitting gamma radiation. Gamma cameras commonly are used in scintigraphy nuclear medical imaging. They also are used in positron emission tomography (PET) and single photon emission computed tomography (SPECT), imaging techniques that require some form of adaptation of the camera but produce three – dimensional images for diagnostic evaluation.

In the scintigraphy imaging technique, the imaging subject receives a compound containing radionuclides that emit gamma rays. The compound can be injected, ingested or inhaled, depending on the application. The gamma camera creates an image by registering gamma photons as they leave the patient. It accomplishes this by capturing the escaping gamma photons, and recording data on the momentary flash of light created on the crystal by atomic activity in response to the effects of escaping gamma photons. The camera operates in conjunction with a computer, which records the data collected by the camera to produce a two – dimensional image.

The SPECT approach is a common approach to nuclear cardiac stress testing. In this technique, the patient is injected with a radionuclide – bearing radioactive pharmaceutical. As gamma photons then escape from the patient, a camera containing one to three detector heads rotates slowly around the patient’s torso to record emission data. A computer program integrates the collected data to produce a three – dimensional image.