An international journal published by K. N. Toosi University of Technology

Document Type : Research Article


1 Medical Physics Department, School of Medicine, Iran University of Medical Sciences, P.O. Box: 14155-6183, Tehran, Iran

2 Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA 23219, USA


It is important to have accurate information regarding the dose distribution for treatment planning and to accurately deposit that dose in the tissue surrounding the brachytherapy source. However, the practical measurement of dose distribution for various reasons is associated with several problems. In this study, 6711 I-125, Micro Selectron mHDR-v2r Ir-192, and Flexisource Co-60 sources were simulated using the MCNP5 Monte Carlo method. To simulate the sources, the exact geometric characteristics of each source, the material used in them, and the energy spectrum of each source were entered as input to the program, and finally, the dosimetric parameters including dose rate constant, radial dose function, and anisotropy function were calculated for considered seeds according to AAPM, TG-43 protocol recommendation. Results obtained for dosimetric parameters of dose rate constant, radial dose function, and anisotropy function for I-125, Ir-192, and Co-60 sources agreed with other studies. According to the good agreement obtained between the parameters of TG43 and other studies, now these datasets can be used as input in the treatment planning systems and to validate their calculations.


  • Dose rate constant was obtained for I-125, Ir-192 and Co-60 brachytherapy sources using MCNP5 code.
  • Radial dose function parameter g(r) was obtained for I-125, Ir-192, and Co-60 using MCNP5 code.
  • Anisotropy function F(r,θ) was obtained for I-125, Ir-192, and Co-60 using MCNP5 code.
  • All calculated parameters for I-125, Ir-192 and Co-60 brachytherapy sources were in consistent with reference studies.


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