title: Factors involved in the detection of pulmonary emboli by labelling techniques.
abstract: Experiments were set up to assess quantitatively the problem of detecting, by scanning and gamma-camera, labelled pulmonary emboli in the presence of background radioactivity. In vitro, a relative concentration of radioactivity of 2:1 was required to detect a 1-1 cm diameter "hot spot". The results in vivo suggest that the level of radioactivity of a pulmonary embolus situated in the centre of the lung field should be at least six times that of the circulating blood.
mesh_terms: D000818:Animals; D001417:Background Radiation; D004285:Dogs; D007553:Isotope Labeling; D008961:Models, Structural; D011655:Pulmonary Embolism / Q000175:diagnosis*; D011877:Radionuclide Imaging; D012711:Serum Albumin, Radio-Iodinated
chemical_list: D012711:Serum Albumin, Radio-Iodinated