Room: Exhibit Hall | Forum 9
Purpose: The internal dosimetry used in nuclear medicine will be affected by the sizes and geometry of the source and target organs. Currently, there are no database of organ dose conversion factors for Chinese Female, leading to potential dose underestimation for this population. This study simulated a Chinese Female phantom and calculated organ doses owing to F-18, C-11, and Ga-68 omitted from different source organs.
Methods: This study used EGS4-VLSI to simulate CRAF66 voxel phantom organ doses for F-18, C-11, and Ga-68 β+ emitters. The results for F-18 were first compared to those published by Stabin et al. for benchmark, and the organ dose conversion factors for Chinese Female for F-18, C-11, and Ga-68 were calculated and tabulated.
Results: When source organ is also target organ, because β+ is weak penetrating, dose of Source organ/Target organ is inversely proportional to the mass of the organ. Thus, Stabin's results will underestimate internal doses for Chinese female because Chinese female has smaller organ sizes. Also, female organs (uterus and ovaries) in Stabin's results maybe unreal because of inaccurate geometry of bi-sexsual phantom used.
Conclusion: The internal doses calculated using bisexual phantom based on western population may be unrealistic and unsuitable for Chinese Female. The assessment of internal dosimetry to Chinese adult female is important for better assess their internal organ dose when taking PET imaging.