Question: Arkansas Subscriber Answer: Code 79101 (Radiopharmaceutical therapy, by intravenous administration) is appropriate for IV administration for radiopharmaceutical therapy. You should not use it for a diagnostic test such as 78452 (Myocardial perfusion imaging, tomographic [SPECT] [including attenuation correction, qualitative or quantitative wall motion, ejection fraction by first pass or gated technique, additional quantification, when performed]; multiple studies, at rest and/or stress [exercise or pharmacologic] and/or redistribution and/or rest reinjection). Don't forget: