Determination of Dosimetric Parameters of New Brachytherapy Seed (125IrSeed) Using EBT Radiochomic Film and TL Dosimeters

Low dose rate brachytherapy sources have been used widely for interst-itial implants in tumor sites، particularly in prostate cancer. Recently، several new desi-gns of 125I and 103Pd sources have become commercially available for clinical appli-cations. In this research، dosimetric characteristics of a new IrSeed 125I brachytherapy source has been deter-mined using LiF thermoluminescent (TLD) chips and EBT radiochromic film. Dose distributions around the IrSeed 125I source were measured in a Plexiglass phantom using TLD-100 LiF thermoluminescent dosimeters and EBT radiochromic film. Quantities such as radial dose fu-nction، g (r) for distances 2،3 and 5 cm، and anisotropy function، F (r،θ)، for angels 0-180º were experimentally determined and the geometry function، G (r،θ)، was calcul-ated. Discussion & The dose rate constant، Λ، was measured to be 0. 965±0. 06 cGyh-1U-1. The dosimetric par-ameters that have presented for this new source، may have many clinical appli-cations.