Experimental validation of radiopharmaceutical absorbed dose to mineralized bone tissue

Therapeutic and palliative uses of bone-seeking radiopharmaceuticals are undergoing clinical trials for human subjects. Radiation dosimetry for these applications is based on the Medical Internal Radiation Dosimetry (MIRD) schema. An experimental method for dosimetry of bone tissue based on electron paramagnetic resonance (EPR) spectrometry is described. Preliminary results for beagle bone exposed to radiopharmaceuticals under clinical conditions have indicated that the EPR dose measurements give approximately the calculated dose, but suggest that the dose distribution may be non-uniform.