The pressures imposed by a rapidly expanding knowledge base and escalating time constraints create a dilemma for diagnostic radiologists; the dilemma becomes particularly acute for low volume studies such as Tc-99m MAG3 renography where many radiologists have had limited training and experience. We propose to complete the development of a comprehensive decision support system that will automatically process MAG3 renal scans, identify and correct quality control problems, and incorporate clinical data to interpret MAG3 renal scans in regard to normality, function, obstruction and renovascular hypertension as well as expert nuclear medicine physicians. We expect that this decision support system will better define the essential interpretative criteria, foster standardized interpretation, teach radiologists and trainees to better interpret renal scans, enhance the diagnostic accuracy of the general radiologist in clinical practice and provide a methodology applicable to other diagnostic problems in radiology and medicine. ? ? ?