EGSnrc Monte Carlo calculated dosimetry parameters for 192Ir and 169Yb brachytherapy sources

This study presents the results of EGSnrc Monte Carlo calculations of the dose distribution surrounding a high dose rate 169Yb brachytherapy source and 14 high dose rate and pulsed dose rate 192Ir brachytherapy sources. Energy-weighted spectra of emitted photons, a full set of TG-43 dosimetry parameters, along-away dose tables, and a description of the materials and geometry used for each source are provided. In addition to this, separate tallies are made of the dose contributed from primary, single-scattered, and multiply-scattered photons. Separation of dose in this manner allows one to use convolution/superposition methods to calculate the dose surrounding a brachytherapy source accounting for a non-homogeneous medium. The effect of phantom size on TG-43 dosimetry parameters and scattered dose is also investigated for the 192Ir microSelectron v2 HDR source. This paper describes the calculation methods and presents the dose rate constants calculated for each source with the full set of dosimetry data being available online at the Carleton Laboratory for Radiotherapy Physics brachytherapy database (http://www.physics.carleton.ca/clrp/seed lowbar database/).