title: Effect of lung volume on counting efficiency: a Monte Carlo investigation.
abstract: Lung counters are usually calibrated with an anthropometric phantom that has a fixed lung size; however, people have widely varying lung sizes (both volume and dimensions). This work uses a simple Monte Carlo simulation to investigate the effect on the counting efficiency of a lung counter based on a four detector array of 50 mm diameter, 70 mm diameter, or 85 mm diameter as lung size varies. The simulations were carried out at several photon energies (17, 60, 120, and 1,000 keV). Comparing the simulated efficiencies with a reference value close to the lung volume of Reference Man, biases in the range of -21% to 63% were discovered. The values from the Monte Carlo simulation have also been compared with some literature data based on experimental measurements, and the agreement was found to be comparable suggesting that lung volume is indeed a factor that should be considered when trying to make an accurate estimate of a lung burden.
authors.affiliation: Human Monitoring Laboratory, Radiation Protection Bureau, 775 Brookfield Road, Ottawa, Ontario K1A 1C1, Canada. gary_h_kramer@hc-sc.gc.ca
authors.forename: Gary H
authors.initials: GH
authors.lastname: Kramer
authors.forename: Kevin
authors.initials: K
authors.lastname: Capello
mesh_terms: D000465:Algorithms; D032701:Biomimetics / Q000295:instrumentation / Q000379:methods; D001822:Body Burden; D002170:Canada; D003198:Computer Simulation; D008168:Lung / Q000033:anatomy & histology* / Q000502:physiology*; D008954:Models, Biological; D009010:Monte Carlo Method; D009929:Organ Size / Q000502:physiology*; D009928:Organ Specificity; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011868:Radioisotopes / Q000032:analysis*; D012062:Relative Biological Effectiveness; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013990:Tidal Volume / Q000502:physiology; D014915:Whole-Body Counting / Q000295:instrumentation* / Q000379:methods* / Q000592:standards
chemical_list: D011868:Radioisotopes