An absorbed dose map of bone tissue treated with a radiopharmaceutical in vivo.

A beagle humerus treated with Ho-chelate radiopharmaceutical in vivo was examined by electron paramagnetic resonance (EPR) dosimetry. The bone was sectioned and the absorbed dose to each bone fragment was determined by additive re-irradiation of the bone tissue with calibrated doses of gamma radiation. The measured doses ranged from 4.3 Gy to 62 Gy. The highest doses were recorded in the predominately trabecular bone tissue and the lowest doses in the predominately cortical bone tissue. The mean absorbed dose for the entire bone was 17 Gy. The data from 50 bone fragments were combined to create an absorbed dose map of the interior bone surface.