Abstract
Ytterbium-169 citrate has recently been put into medical use for external imaging of tumor tissues. The skeletal absorbed dose received by the patient was estimated in accordance with the MIRD Committee method. 500 micro-curie intravenous injection proved to result in 13 rads in skeleton, with the most important contribution of the internal conversion electrons emitted in the electron capture decaying process of the nuclide. The contribution of the penetrating radiations originating in other organs was found to be negligibly small. The average total body dose was approximately 2 rads.
