Abstract：
PURPOSE:The combination of nonhuman primates (NHPs) with the state-of-the-art molecular imaging technologies allows for within-subject longitudinal research aiming at gaining new insights into human normal and disease conditions and provides an ideal foundation for future translational studies of new diagnostic tools, medical interventions, and therapies. However, radiation dose estimations for nonhuman primates from molecular imaging probes are lacking and are difficult to perform experimentally. The aim of this work is to construct age-dependent NHP computational model series to estimate the absorbed dose to NHP specimens in common molecular imaging procedures. MATERIALS AND METHODS:A series of NHP models from baby to adult were constructed based on nonuniform rational B-spline surface (NURBS) representations. Particle transport was simulated using Monte Carlo calculations to estimate S-values from nine positron-emitting radionuclides and absorbed doses from PET radiotracers. RESULTS:Realistic age-dependent NHP computational model series were developed. For most source-target pairs in computational NHP models, differences between C-11 S-values were between -13.4% and -8.8%/kg difference in body weight while differences between F-18 S-values were between -12.9% and -8.0%/kg difference in body weight. The absorbed doses of 11 C-labeled brain receptor substances, 18 F-labeled brain receptor substances, and 18 F-FDG in the brain ranged within 0.047-0.32 mGy/MBq, 0.25-1.63 mGy/MBq, and 0.32-2.12 mGy/MBq, respectively. CONCLUSION:The absorbed doses to organs are significantly higher in the baby NHP model than in the adult model. These results can be used in translational longitudinal studies to estimate the cumulated absorbed organ doses in NHPs at various ages.
journal_name
Med Physjournal_title
Medical physicsauthors
Xie T,Chen X,Zaidi Hdoi
10.1002/mp.14333subject
Has Abstractpub_date
2020-09-01 00:00:00pages
4465-4476issue
9eissn
0094-2405issn
2473-4209journal_volume
47pub_type
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