An Optimized Method for Evaluating the Potential Gd-Nanoparticle Dose Enhancement Produced by Electronic Brachytherapy

This work reports an optimized method to experimentally quantify the Gd-nanoparticle dose enhancement generated by electronic brachytherapy. The dose enhancement was evaluated considering energy beams of 50 kVp and 70 kVp, determining the Gd-nanoparticle concentration ranges that would optimize the...

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Detalles Bibliográficos
Autores: Fuentealba, M, Ferreira, A, Salgado, A, Vergara, C, Díez, S, Santibáñez, M
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:INCLIVA
Repositorio:r-INCLIVA. Repositorio Institucional de Producción Científica de INCLIVA
OAI Identifier:oai:incliva.fundanetsuite.com:p19565
Acceso en línea:https://incliva.portalinvestigacion.com/publicaciones/19565
Access Level:acceso abierto
Palabra clave:dose enhancement
delaminated EBT3 films
Gd nanoparticles
Descripción
Sumario:This work reports an optimized method to experimentally quantify the Gd-nanoparticle dose enhancement generated by electronic brachytherapy. The dose enhancement was evaluated considering energy beams of 50 kVp and 70 kVp, determining the Gd-nanoparticle concentration ranges that would optimize the process for each energy. The evaluation was performed using delaminated radiochromic films and a Poly(methyl methacrylate) (PMMA) phantom covered on one side by a thin 2.5 mu m Mylar filter acting as an interface between the region with Gd suspension and the radiosensitive film substrate. The results for the 70 kVp beam quality showed dose increments of 6 +/- 6%, 22 +/- 7%, and 9 +/- 7% at different concentrations of 10, 20, and 30 mg/mL, respectively, verifying the competitive mechanisms of enhancement and attenuation. For the 50 kVp beam quality, no increase in dose was recorded for the concentrations studied, indicating that the major contribution to enhancement is from the K-edge interaction. In order to separate the contributions of attenuation and enhancement to the total dose, measurements were replicated with a 12 mu m Mylar filter, obtaining a dose enhancement attributable to the K-edge of 29 +/- 7% and 34 +/- 7% at 20 and 30 mg/mL, respectively, evidencing a significant additional dose proportional to the Gd concentration.