Visualization of isotope distribution within the living body has created important medical diagnostic procedures during the last decade. The static gamma-ray cameras reviewed here are often replacing the earlier mechanical scanners because of their ability to reduce picture exposure times: in extreme cases from minutes to tenths of seconds. Motion picture photography of changing isotope distribution can thus be used to follow many physiological processes which were previously a mystery, and these dynamic studies offer completely new diagnostic methods. This paper reviews the development of static gamma-ray cameras, discusses the problems of their design, and attempts to evaluate the limitations of each type. Methods of judging camera quality are discussed, and there is also brief mention of analytical methods for picture assessment.
MOODY ET AL.: MEDICAL GAMMA-RAY CAMERAS 219Recent theoretical work by Beck [50] suggests that an energy of 150 keV is optimum, but it has not been established that his model completely represents the clinical situation...