MODEL RELEASED. Gamma camera scan. Male patient receives a gamma scan of his neck and upper chest area. The gamma camera (upper left) is being positioned by one radiologist, while another sits at a computer screen. On the screen are coloured tracer images made by the camera. A gamma camera is used widely in the detection and management of cancers. The gamma scan is a map of the distribution of radioactivity emitted from a radioactive tracer that is injected and concentrated in the part of the body under investigation. Each radiation burst is detected as a flash of light and processed electronically to provide an image.