Dosimetry parameters calculation of two commercial iodine brachytherapy sources using SMARTEPANTS with EPDL97 library

Abstract

Aim: Simulating Many Accumulative Rutherford Trajectories Electron Photon and Neutral Transport Solver (SMARTEPANTS) is a discrete ordinates S N Boltzmann/Spencer-Lewis solver that was developed during 1988-1993 by William Filippone and his students. The code calculates particle fluxes, leakage currents as well as energy and charge deposition for coupled electron/photon in x-y-z geometries both in forward and in adjoin modes. Originally, SMARTEPANTS was designed to utilize CEPXS cross-section library for shielding calculation in satellite electronics. The aim of this study was to adapt SMARTEPANTS to use a new photon cross-section library from Evaluated Photon Data Library, 1997 version (EPDL97) for intravascular brachytherapy 125 Isimulations. Materials and Methods: A MATLAB (MathworkNatick, Massachusetts) program was written to generate an updated multigroup-Legendre cross-section from EPDL97. The new library was confirmed by simulating intravascular brachytherapy Best® Model 2301 and Intersource 125 I dosimetry parameters using SMARTEPANTS with different energy groups (g), Legendre moments (L) and discrete ordinate orders (S). Results: The dosimetry parameters for these sources were tabulated and compared with the data given by AAPM TG-43 and other reports. The computation time for producing TG-43 parameters was about 29.4 min in case of g = 20, L = 7 and S = 16. Conclusion: The good agreement between the results of this study and previous reports and high computational speed suggest that SMARTEPANTS could be extended to a real-time treatment planning system for 125 I brachytherapy treatments.