title: Iridium- 191 angiocardiography for the detection and quantitation of left-to-right shunting.
abstract: An osmium- 191 leads to iridium- 191 generator that can deliver multiple doses of Ir- 191m for first-pass radionuclide angiography has been developed. Iridium- 191m has a physical half-life of 4.96 sec and decays with emission of 65-keV and 129-keV photons in 58 and 30% abundance, respectively. Using a gamma camera, Ir- 191m radionuclide angiography was carried out, in dogs and ten patients, for the detection and quantitation of left-to-right shunting. In a one-year-old patients, 25 mCi of Ir- 191m results in a whole-body radiation absorbed dose of 35 mrad. Multiple Ir- 191m angiograms can be performed, seconds to minutes apart, without interference from background. The 15.4-day half-life of Os- 191 permits transportation of the generator to centers far from the production facility. With the low radiation dose, high information density, and the ability to repeat studies with Ir- 191m, clinical use of radionuclide angiography should be expanded.
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001783:Blood Flow Velocity; D002675:Child, Preschool; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004285:Dogs; D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005069:Evaluation Studies as Topic; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006343:Heart Septal Defects / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007495:Iridium; D008297:Male; D011868:Radioisotopes; D011876:Radionuclide Generators; D011877:Radionuclide Imaging; D013667:Technetium; D013997:Time Factors
chemical_list: D011868:Radioisotopes; D007495:Iridium; D013667:Technetium