Rights managed images relating to the diagnostic technique of gamma scanning (scintigraphy). In this medical procedure a radioactive isotope is injected into the body, which accumulates in the tissues to be studied (commonly bone). Detection of the gamma radiation given off by the tracer isotope enables a picture of the body structure to be obtained. This technique is often used for locating bone tumours or assessing bone structure. Other uses shown here include diagnosing cancer, assessing the health of the thyroid gland, and tracking blood flow in organs such as the kidney, liver, heart and brain. A related technique, SPECT (single positron emission computed tomography), is also shown here.