title: A MONTE CARLO STUDY OF SIMULATED MEASUREMENTS OF RADIONUCLIDES IN BONE.
abstract: When measuring the internally deposited activity in the bone of a subject, the placement of the detector is critical. This study reports the simulated counting efficiencies for three counting geometries, the skull, knee and shin, using 13 different voxel phantoms. It shows that the range of counting efficiencies for a given geometry is large for the studied phantoms, especially at low energies. Skull counting offers higher efficiency for low energies such as the 17 keV compared to knee counting or shin counting, but this advantage disappears when the energy is higher such as at 185 keV. This work also shows that the calibration phantom may greatly impact the accuracy of the activity estimate in bone counting, with uncertainties increasing greatly as the photon energy is reduced. Estimating the activity of a radionuclide in bone from direct counting has large uncertainties, and the dose calculated from a skeleton measurement would need careful analysis and, if possible, supporting data from other bioassay measurements.
authors.affiliation: Radiation Protection Bureau, Health Canada, 775 Brookfield Rd, Ottawa, Canada K1A 1C1 li.chunsheng@hc-sc.gc.ca.
authors.forename: C
authors.initials: C
authors.lastname: Li
authors.affiliation: Radiation Protection Bureau, Health Canada, 775 Brookfield Rd, Ottawa, Canada K1A 1C1.
authors.forename: K
authors.initials: K
authors.lastname: Capello
authors.affiliation: Radiation Protection Bureau, Health Canada, 775 Brookfield Rd, Ottawa, Canada K1A 1C1.
authors.forename: B
authors.initials: B
authors.lastname: Hauck
authors.affiliation: Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, Research Unit Medical Radiation Physics and Diagnostics, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Zankl
authors.affiliation: Radiation Protection Bureau, Health Canada, 775 Brookfield Rd, Ottawa, Canada K1A 1C1.
authors.forename: G
authors.initials: G
authors.lastname: Kramer
mesh_terms: D000328:Adult; D001822:Body Burden; D001842:Bone and Bones / Q000528:radiation effects*; D002138:Calibration; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007717:Knee / Q000528:radiation effects; D007866:Leg / Q000528:radiation effects; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D017785:Photons; D011868:Radioisotopes / Q000032:analysis*; D012886:Skull / Q000528:radiation effects; D012984:Software; D014915:Whole-Body Counting / Q000379:methods*
chemical_list: D011868:Radioisotopes