TY - JOUR
T1 - A simple model for calculating relative biological effectiveness of X-rays and gamma radiation in cell survival
AU - Vassiliev, Oleg N.
AU - Peterson, Christine B.
AU - Grosshans, David R.
AU - Mohan, Radhe
N1 - Publisher Copyright:
© 2020 British Institute of Radiology. All rights reserved.
PY - 2020/8/1
Y1 - 2020/8/1
N2 - Objectives: The relative biological effectiveness (RBE) of X-rays and γ radiation increases substantially with decreasing beam energy. This trend affects the efficacy of medical applications of this type of radiation. This study was designed to develop a model based on a survey of experimental data that can reliably predict this trend. Methods: In our model, parameters α and β of a cell survival curve are simple functions of the frequency-average linear energy transfer (LF) of delta electrons. The choice of these functions was guided by a microdosimetry-based model. We calculated LF by using an innovative algorithm in which LF is associated with only those electrons that reach a sensitive-to- radiation volume (SV) within the cell. We determined model parameters by fitting the model to 139 measured (α,β) pairs. Results: We tested nine versions of the model. The best agreement was achieved with __ and β being linear functions of LF .The estimated SV diameter was 0.1-1 μm. We also found that α, β, and the α/β ratio increased with increasing LF . Conclusions: By combining an innovative method for calculating LF with a microdosimetric model, we developed a model that is consistent with extensive experimental data involving photon energies from 0.27 keV to 1.25 MeV.
AB - Objectives: The relative biological effectiveness (RBE) of X-rays and γ radiation increases substantially with decreasing beam energy. This trend affects the efficacy of medical applications of this type of radiation. This study was designed to develop a model based on a survey of experimental data that can reliably predict this trend. Methods: In our model, parameters α and β of a cell survival curve are simple functions of the frequency-average linear energy transfer (LF) of delta electrons. The choice of these functions was guided by a microdosimetry-based model. We calculated LF by using an innovative algorithm in which LF is associated with only those electrons that reach a sensitive-to- radiation volume (SV) within the cell. We determined model parameters by fitting the model to 139 measured (α,β) pairs. Results: We tested nine versions of the model. The best agreement was achieved with __ and β being linear functions of LF .The estimated SV diameter was 0.1-1 μm. We also found that α, β, and the α/β ratio increased with increasing LF . Conclusions: By combining an innovative method for calculating LF with a microdosimetric model, we developed a model that is consistent with extensive experimental data involving photon energies from 0.27 keV to 1.25 MeV.
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U2 - 10.1259/bjr.20190949
DO - 10.1259/bjr.20190949
M3 - Article
C2 - 32464080
AN - SCOPUS:85088495967
SN - 0007-1285
VL - 93
JO - British Journal of Radiology
JF - British Journal of Radiology
IS - 1112
M1 - 20190949
ER -