Differential dose contributions on total dose distribution of 125I brachytherapy source

Abstract

This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 (125)I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total dose at analytical calculation point. Some brachytherapy seeds contain multi-radioactive elements so the dose at any point is a total of separate doses from each element. It is momentous to know well the angular and radial dose distributions around the source that is located in cancerous tissue for clinical treatments. Interior geometry of a source is effective on dose characteristics of a distribution. Dose information of inner geometrical structure of a brachytherapy source cannot be acquired by experimental methods because of limits of physical material and geometry in the healthy tissue, so Monte Carlo simulation is a required approach of the study. EGSnrc Monte Carlo simulation software was used. In the design of a simulation, the radioactive source was divided into 10 rings, partitioned but not separate from each other. All differential sources were simulated for dose calculation, and the shape of dose distribution was determined comparatively distribution of a single-complete source. In this work anisotropy function was examined also mathematically.

A Monte Carlo evaluation for effects of probable dimensional uncertainties of low dose rate brachytherapy seeds on dose

“…In addition, it can be said that MC studies on geometrical uncertainties can be useful to investigate a secondary subject. 16 Clinical applications should be optimized for dimensional deviations of the brachytherapy seeds since small changes in dimensions cause remarkable dose deviation as understood from this study. Also dosimetric parameters as suggested in TG-43 report should include dimension uncertainties.…”

Investigation of dose distribution of TheraSeed 200 103Pd brachytherapy seed on coaxial cylindrical phantom shells using Monte Carlo simulation

“…EGSnrc Code simulation design of brachytherapy seed was studied successfully. The code and dosimetric parameter of a seed were calculated in agreement with the published data [9].…”

Evaluation of clinical benefits achievable by using different optimization algorithms during real-time prostate brachytherapy

“…The use of this combined treatment scheme is possible by developing theoretical and experimental studies, brachytherapy equipment and facilities, computer devices with treatment planning software, and, of course, clinical experience [10]. Consequently, all advanced technology available for iridium-192 brachytherapy has made anatomyrelated dose optimization possible [11].…”