Determination of dose calculation parameters of model 81-02 198Au brachytherapy source with Monte-Carlo method

Dosimetry parameters, including dose rate constant, radial dose function and anisotropy function, of model 81-02 198Au brachytherapy source were calculated in a 30 cm radius theoretical sphere by Monte-Carlo method for clinical application. For the single source, the deviation of dose rate constant is 1.113 cGy · h-1 · U-1, and within 0.18% and 1.62% from the calculated and measured value (TLDs) of Dauffy et al. Calculated value of radial dose function, g(r), is in the rang of 0.1-10.0 cm at transverse axis. Anisotropy function, F(r, θ), is calculated in 0 degree-90 degree of θ with increment of 10 degree and 0.5-9.0 cm of r with increment of 1 cm. Empiric equations are acquired for radial dose function and anisotropy function by curve fitting. (authors)