Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application
The spatial distribution of energy deposition events is an essential aspect in the determination of the radiobiological effects of ionizing radiation at the cellular level. Microdosimetry provides a theoretical framework for the description of these events, and has been used in several studies to ad...
| Authors: | ; ; ; ; |
|---|---|
| Format: | Article |
| Status: | Published version |
| Publication date: | 2021 |
| Country: | España |
| Institution: | Universidad de Sevilla (US) |
| Repository: | idUS. Depósito de Investigación de la Universidad de Sevilla |
| OAI Identifier: | oai:idus.us.es:11441/127574 |
| Online Access: | https://hdl.handle.net/11441/127574 https://doi.org/10.3389/fphy.2021.726787 |
| Access Level: | Open access |
| Keyword: | Dose-averaged LET Geant4-DNA Lineal energy Microdosimetry Proton therapy Site sampling method |
| _version_ | 1878732778680352768 |
|---|---|
| author | Baratto Roldán, Anna |
| author2 | Bertolet, Alejandro Baiocco, Giorgio Carabe, Alejandro Cortés Giraldo, Miguel Antonio |
| author2_role | author author author author |
| author_browse | Baiocco, Giorgio Baratto Roldán, Anna Bertolet, Alejandro Carabe, Alejandro Cortés Giraldo, Miguel Antonio |
| author_facet | Baratto Roldán, Anna Bertolet, Alejandro Baiocco, Giorgio Carabe, Alejandro Cortés Giraldo, Miguel Antonio |
| author_role | author |
| collection | idUS. Depósito de Investigación de la Universidad de Sevilla |
| description | The spatial distribution of energy deposition events is an essential aspect in the determination of the radiobiological effects of ionizing radiation at the cellular level. Microdosimetry provides a theoretical framework for the description of these events, and has been used in several studies to address problems such as the characterization of Linear Energy Transfer (LET) and Relative Biological Effectiveness (RBE) of ion beams for proton therapy applications. Microdosimetry quantities and their distributions can be obtained by means of Monte Carlo simulations. In this work, we present a track structure Monte Carlo (MC) application, based on Geant4-DNA, for the computation of microdosimetric distributions of protons in liquid water. This application provides two sampling methods uniform and weighted, for the scoring of the quantities of interest in spherical sites, with diameters ranging from 1 to 10 μm. As an element of novelty, the work shows the approach followed to calculate, without resorting to dedicated simulations, the distribution of energy imparted to the site per electronic collision of the proton, which can be used to obtain the macroscopic dose-averaged LET as proposed by Kellerer. Furthermore, in this work the concept of effective mean chord length is proposed to take into account δ-ray influx and escape in the calculation of macroscopic dose-averaged LET for proton track segments and retrieve the agreement predicted by Kellerer’s formula. Finally, the results obtained demonstrate that our MC application is reliable and computational-efficient to perform calculations of microdosimetric distributions and dose-averaged LET of proton track segments in liquid water. |
| eu_rights_str_mv | openAccess |
| format | article |
| id | ES_4998f2a4de2da5a3eefa5ce1e1dca99a |
| institution | Universidad de Sevilla (US) |
| instname_str | Universidad de Sevilla (US) |
| network_acronym_str | ES |
| network_name_str | España |
| oai_identifier_str | oai:idus.us.es:11441/127574 |
| publishDate | 2021 |
| publishDateSort | 2021 |
| publisher | Frontiers Media S.A. |
| publisherStr | Frontiers Media S.A. |
| reponame_str | idUS. Depósito de Investigación de la Universidad de Sevilla |
| spelling | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application Baratto Roldán, Anna Bertolet, Alejandro Baiocco, Giorgio Carabe, Alejandro Cortés Giraldo, Miguel Antonio Dose-averaged LET Geant4-DNA Lineal energy Microdosimetry Proton therapy Site sampling method The spatial distribution of energy deposition events is an essential aspect in the determination of the radiobiological effects of ionizing radiation at the cellular level. Microdosimetry provides a theoretical framework for the description of these events, and has been used in several studies to address problems such as the characterization of Linear Energy Transfer (LET) and Relative Biological Effectiveness (RBE) of ion beams for proton therapy applications. Microdosimetry quantities and their distributions can be obtained by means of Monte Carlo simulations. In this work, we present a track structure Monte Carlo (MC) application, based on Geant4-DNA, for the computation of microdosimetric distributions of protons in liquid water. This application provides two sampling methods uniform and weighted, for the scoring of the quantities of interest in spherical sites, with diameters ranging from 1 to 10 μm. As an element of novelty, the work shows the approach followed to calculate, without resorting to dedicated simulations, the distribution of energy imparted to the site per electronic collision of the proton, which can be used to obtain the macroscopic dose-averaged LET as proposed by Kellerer. Furthermore, in this work the concept of effective mean chord length is proposed to take into account δ-ray influx and escape in the calculation of macroscopic dose-averaged LET for proton track segments and retrieve the agreement predicted by Kellerer’s formula. Finally, the results obtained demonstrate that our MC application is reliable and computational-efficient to perform calculations of microdosimetric distributions and dose-averaged LET of proton track segments in liquid water. Ministerio de Ciencia e Innovación RTI2018-098117-B-C21, 10.13039/501100011033 European Union 675265 Frontiers Media S.A. https://hdl.handle.net/11441/127574 https://doi.org/10.3389/fphy.2021.726787 |
| spellingShingle | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application Baratto Roldán, Anna Dose-averaged LET Geant4-DNA Lineal energy Microdosimetry Proton therapy Site sampling method |
| status_str | publishedVersion |
| title | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| title_full | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| title_fullStr | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| title_full_unstemmed | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| title_short | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| title_sort | Microdosimetry and Dose-Averaged LET Calculations of Protons in Liquid Water: A Novel Geant4-DNA Application |
| topic | Dose-averaged LET Geant4-DNA Lineal energy Microdosimetry Proton therapy Site sampling method |
| topic_facet | Dose-averaged LET Geant4-DNA Lineal energy Microdosimetry Proton therapy Site sampling method |
| url | https://hdl.handle.net/11441/127574 https://doi.org/10.3389/fphy.2021.726787 |