Background and purpose: In preparation for using this tracer in humans

this study estimated t

he dosimetry of

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F-FES with the method established by MIRD based on whole-body PET imaging of mice. Methods: Three female mice received Ⅳ tail injections of

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F-FES and were scanned for 160 min in an Inveon dedicated PET/CT scanner. This study selected some important organs (brain

lung

liver

heart wall

small intestine

large intestine

kidney and urinary bladder)

computed their residence times. Then

the residence times in mice organs were converted to human values using scale factors based on differences between organ and body weights. OLINDA/EXM 1.1 software was used to compute the absorbed human doses in multiple organs for both adult female and adult male body phantoms. Results: The highest absorbed doses in gallbladder wall

urinary bladder wall

small intestine

upper large intestine and liver are 0.072 5

0.044 5

0.043 0

0.031 5 and 0.028 2 mGy/MBq

respectively. The organs which have the lowest absorbed doses were brain (0.005 2 mGy/MBq)

followed by skin (0.001 1 mGy/MBq)

breast (0.001 1 mGy/MBq)

heart wall (0.001 2 mGy/MBq) and thyroid (0.001 2 mGy/MBq). The mean absorbed doses for the other major organs ranged from 0.009 5 to 0.023 5 mGy/MBq. The total mean effective dose is 0.019 0 mSv/MBq and the mean effective doses equivalent is 0.025 0 mGy/MBq. A 370-MBq injection of

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F-FES leads to an estimated effective dose of 7.03 mSv for the female. There was no statistical difference in the doses results obtained from direct measurement of

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F-FES absorption in normal people between previous publications by others and our work. Conclusion: The whole-body mouse imaging can be used as a preclinical tool for initial estimation of the absorbed doses of

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F-FES in humans. Furthermore

the potential radiation risk associated with

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F-FES imaging is well within the accepted limits.