High-precision γ -ray spectroscopy of the cardiac PET imaging isotope Rb 82 and its impact on dosimetry

Rb-82 is a positron-emitting isotope used in cardiac positron emission tomography (PET) imaging which has been reported to deliver a significantly lower effective radiation dose than analogous imaging isotopes like Tl-201 and Tc-99m sestamibi. High-quality beta-decay data are essential to accurately appraise the total dose received by the patients. A source of Sr-82 was produced at the Brookhaven Linac Isotope Producer (BLIP), transported to Argonne National Laboratory, and studied with the Gammasphere facility. Significant revisions have been made to the level scheme of Kr-82 including 12 new levels, 50 new gamma-ray transitions, and the determination of many new spin assignments through angular correlations. These new high-quality data allow a precise reappraisal of the beta-decay strength function and thus the consequent dose received by patients.