What is nuclear medicine all about?

Abstract

The field of nuclear medicine, defined as the application of radioactive tracers to medical diagnosis and treatment, has progressed significantly over recent years. At one time, only measurements of the concentrations of the radioactive tracers or other chemicals in blood, urine or other biologic material could be obtained at various intervals after the administration of a tracer or chemical. Therefore, prior to development of radiation detectors that reveal the distribution of radioactive tracers within the body, the function of the body could be studied only as a whole. It now is possible to study both regional and total body function by using the many radioactive tracers available and suitable imaging devices. By using the short-lived tracers (which have improved the quality of the images and reduced the radiation dose to the patient) and the recently developed scintillation camera, rapid dynamic studies of the course of the tracers through regions of the body may be performed, so that both spatial and temporal resolution is obtained. The use of computers has added a new dimension to the field of nuclear medicine. It is possible to improve greatly the quality of the information obtained. As a result, the regional distribution of radioactivity can be quantified and the changes that take place over a period of time in serial studies evaluated. Thus using a variety of radioactive tracers, each measuring a specific function, we can construct a mosaic of quantitative measurements of regional function. In this way, nuclear medicine may develop a body of coherent knowledge and become a clinical science as well as a collection of useful technics.