Feasibility of dose enhancement assessment: Preliminary results by means of Gd-infused polymer gel dosimeter and Monte Carlo study

This work reports the experimental development of an integral Gd-infused dosimeter suitable for Gd dose enhancement assessment along with Monte Carlo simulations applied to determine the dose enhancement by radioactive and X-ray sources of interest in conventional and electronic brachytherapy. In this context, capability to elaborate a stable and reliable Gd-infused dosimeter was the first goal aimed at direct and accurate measurements of dose enhancement due to Gd presence. Dose-response was characterized for standard and Gd-infused PAGAT polymer gel dosimeters by means of optical transmission/absorbance. The developed Gd-infused PAGAT dosimeters demonstrated to be stable presenting similar dose-response as standard PAGAT within a linear trend up to 13 Gy along with good post-irradiation readout stability verified at 24 and 48 h. Additionally, dose enhancement was evaluated for Gd-infused PAGAT dosimeters by means of Monte Carlo (PENELOPE) simulations considering scenarios for isotopic and X-ray generator sources. The obtained results demonstrated the feasibility of obtaining a maximum enhancement around of (14 ± 1)% for 192Ir source and an average enhancement of (70 ± 13)% for 241Am. However, dose enhancement up to (267 ± 18)% may be achieved if suitable filtering is added to the 241Am source. On the other hand, optimized X-ray spectra may attain dose enhancements up to (253 ± 22) %, which constitutes a promising future alternative for replacing radioactive sources by implementing electronic brachytherapy achieving high dose levels. •Novel Gd-infused PAGAT polymer gel dosimeters for evaluation of absolute dose enhancement.•Irradiation with 241Am sources combined with Gd doped inside tumor, like alternative brachytherapy source of high dose enhancement.•Monte Carlo determination of Dose-enhancement by non-symmetrical narrow incident spectrum, centered near to the absorption edge.