Dosimetry of radiopharmaceuticals used in adult patients with suspected pulmonary embolism

Abstract

The absorbed dose of radiopharmaceuticals is estimated in adults with suspected pulmonary embolism explored by ventilation/perfusion studies. For pulmonary ventilation studies81mKr,133Xe,99mTc (Technegas)-aerosol and99mTc (DTPA)-aerosol are used. For perfusion agents,99mTc(MAA),99mTc (MSA) (macroaggregates and albumin microspheres) are used. For the dose calculation, the MIRD methodology and the anthropomorphic representation of the biokinetic organs of Cristy-Eckerman are used. In ventilation/perfusion studies, the lowest dose absorbed by the lungs with suspected embolism is due to81mKr/99mTc (MSA), and the highest dose is due to99mTc (Technegas)/99mTc (MAA) calculated for activities of 150 MBq for perfusion agents and 40 MBq for ventilation agents.