Document Type : Original Paper
Authors
1
Associate Professor, Radiation Application Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, Tehran, Iran
2
Assistant Professor, Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, Karaj, Iran
3
M. Sc. in Medical Applications of Radiation, Nuclear Engineering Dept, Faculty of Engineering, Science and Research Unit, Islamic Azad University, Tehran, Iran
4
B. Sc. in Physics, Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, Karaj, Iran
5
M. Sc. in Medical Physics, Medical Physics Dept., Faculty of Medical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
Abstract
Introduction: The use of low energy isotopes such as 103 Pd in brachytherapy for the treatment of cancers
such as prostate, eye, head, neck, breast and cervix is increasing. In this regard, different models of Pd-
103 seeds have been designed and manufactured at the Agricultural, Medical and Industrial Research
School (AMIRS) of Atomic Energy Organization of Iran. In this research, the dosimetric parameters of
the second model of Pd-103 seed manufactured at AMIRS have been calculated and measured.
Materials and Methods: The dosimetric parameters of the second Pd-103 seed manufactured at AMIRS
were determined according to TG-43U1 protocol using Monte Carlo calculations (MCNP4C computer
code) and measurements performed using TLD-GR200A dosimeters in a Perspex phantom. The
parameters include dose rate constant, geometry function, radial dose function, anisotropy function,
anisotropy factor and anisotropy constant.
Results: It was found that by using MCNP4C code the calculated dose rate constant in water and
Perspex was 0.706±0.001 and 0.501±0.001 cGyh -1 U -1 , respectively. Using the calculated geometry
function, the radial dose function and the anisotropy function were determined by experimental and
theoretical methods in water and Perspex phantom. Also, the calculated value of anisotropy constant in
water was equal to 0.88.
Discussion and Conclusion: A discrepancy of less than 10% between the calculated and the measured
values indicates a reasonable agreement between the simulation and the measurement method. Also, the
dosimetric parameters of this seed have been compared to the dosimetric parameters of the first Pd-103
seed manufactured at AMIRS and some other seeds. The obtained results indicate that the seeds
manufactured at AMIRS have acceptable dosimetric parameters suitable for brachytherapy applications.
Keywords
Main Subjects
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