Acute gastrointestinal bleeding.

Radionuclide bleeding scintigraphy remains a simple yet powerful method of localizing sites of gastrointestinal hemorrhage and is most commonly performed today using the red blood cell technique. Radionuclide techniques for detecting bleeding remain safe, sensitive, and noninvasive. Based on several simple concepts, including the use of cine-mode imaging over the abdomen, it is possible to achieve excellent accuracy in localizing the site of bleeding. Studies often contain additional ancillary information, which is helpful for diagnosis and patient treatment.