99m Technetium labeled RBC scintigraphy is used in the diagnosis of

99m Technetium labeled RBC scintigraphy It is a means of detecting the origin of bleeding when a patient is being investigated for bleeding from the gut. Either Tc99m or Sulfur Colloid Tagged RBC's can be used as the radiotracer to detect GI bleeding Scintigraphy is about It) times more sensitive than angiography for the detection of GI bleeding. The main advantage of using labeled RBC’s is that the agent remains in the intravascular space for 24 (up to 48) hours, thus it is excellent for imaging intermittent or slow bleeds. Liver, spleen, kidneys and bladder (due to excretion of non-erythrocyte bound technetium and labeled hemoglobin fragments) are also visualized, but to a lesser degree and thus will probably not obscure the bleeding focus.