Non-invasive investigation of the upper gastrointestinal tract using technetium-99m

The use of technetium-99m in the noninvasive investigation of the upper gastrointestinal tract is discussed with particular reference to the evolution of a method of assessing gastric function or gastric acid secretion non-invasively and to the applications of this method in the investigation of surgical patients with disease of the upper gastrointestinal tract. The assessment of maximal acid output and the insulin response is described and the use of the test in the diagnosis of pernicious anaemia, hypo- and hyperchlorhydric states, gastric cancer, hiatus hernia and Barrett's oesophagus, coeliac disease, Meckel's diverticulum, and abdominal aortic aneursym outlined. The use of chemicals labelled with this tracer in hepatobiliary scanning is briefly described.