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

Document Type : Research Article


Department of Physics‎, ‎Faculty of Science‎, ‎University of Guilan‎, ‎Postal Code 4193833697‎, ‎Rasht‎, ‎Iran


Low energy I-125- seeds are considered as a common source in different brachytherapy techniques for treatment of different cancers. In this study, at first, we simulated and validated I-125 (model 6711) seed according to the TG-43U1 recommendation, by GEANT4 Monte Carlo toolkit. Moreover, we simulated new seeds containing cylindrical Ag+Al2O3 markers with different ratio of Ag and Al2O3 in the final composition of the marker and compared the radial dose functions and anisotropy functions of the sources. For validation and evaluation purposes, the radial dose function and anisotropy function were calculated at various distances from the center of the different simulated sources. The source validation results show that GEANT4 Monte Carlo toolkit produces accurate results for dosimetric parameters of the I-125 seed by choosing the appropriate physics list. On the other hand, results show a similarity between calculated dosimetric parameters of the I-125 seed (6711) and other sources, with a percentage difference of about 5%.


  • Validation of the I-125 (model 6711) seed according to the TG-43U1 recommendation by GEANT4.
  • Simulation of new seeds containing Ag+Al2O3 markers with different ratio of Ag and Al2O3.
  • Similarity between calculated dosimetric parameters of the I-125 seed (6711) and the new sources.


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