ASSESSING BODY DOSE RATE CONSTANT AND EFFECTIVE BODY ABSORPTION FACTOR IN TAIWANESE REFERENCE PHANTOMS

Abstract

The self-attenuation of a patient's body is an important factor in nuclear medicine for designing radiation shielding. Taiwanese reference man (TRM) and Taiwanese reference woman (TRW) were constructed to simulate the body dose rate constant and the effective body absorption factor for 18F-FDG, 131I-NaI and 99mTc-MIBI using the Monte Carlo technique. For TRM, the maximum body dose rate constants for 18F-FDG, 131I-NaI and 99mTc-MIBI were 1.26 × 10-1, 4.89 × 10-2 and 1.76 × 10-2 mSv-m2/GBq-h, respectively, at heights of 110, 110 and 100 cm. For TRW, the results were 1.23 × 10-1, 4.75 × 10-2 and 1.68 × 10-2 mSv-m2/GBq-h at heights of 100, 100 and 90 cm. The effective body absorption factors were 32.6, 36.7 and 46.2% for TRM and 34.2, 38.5 and 48.6% for TRW. Regional reference phantoms along with the derived body dose rate constant and effective body absorption factor should be used for determining regulatory secondary standards in nuclear medicine.