Analysis of different protocols using an Exradin A12 cylindrical chamber for electron beam reference dosimetry

Andre Gonçalves Prospero; Ana Carolina Ferreira; Diana Rodrigues Pina; Antonio Cesar Pernomian; Wander de Oliveira

doi:10.15392/2319-0612.2023.2232

Authors

Andre Gonçalves Prospero Hospital das Clínicas da Faculdade de Medicina de Botucatu (HCFMB) - Setor de Radioterapia https://orcid.org/0000-0001-5163-8280
Ana Carolina Ferreira University Hospital of the Botucatu Medical School (HCFMB), UNESP, Department of Radiotherapy, 18618-687, Botucatu, São Paulo, Brazil
Diana Rodrigues Pina bUniversity Hospital of the Botucatu Medical School (HCFMB), UNESP, Department of Tropical Diseases and Imaging Diagnosis, 18618-687, Botucatu, São Paulo, Brazil
Antonio Cesar Pernomian University Hospital of the Botucatu Medical School (HCFMB), UNESP, Department of Radiotherapy, 18618-687, Botucatu, São Paulo, Brazil
Wander de Oliveira University Hospital of the Botucatu Medical School (HCFMB), UNESP, Department of Radiotherapy, 18618-687, Botucatu, São Paulo, Brazil

DOI:

https://doi.org/10.15392/2319-0612.2023.2232

Keywords:

electron beam, Dosimetry, cylindrical chambers, parallel plate chambers

Abstract

The Technical Report Series 398 (TRS-398), Electron Dosimetry Working Party (EWDP), and Task Group 51 (TG 51) are the most important protocols for reference dosimetry. In the case of electron beam reference dosimetry, these protocols recommend using parallel-plate ionization chambers for beams with R₅₀ values below specific thresholds. However, recent papers suggested using cylindrical chambers for reference dosimetry of all electron beam energies. Here we compared different protocols using a cylindrical chamber with the recommendations of using a parallel-plate chamber and the TRS-398 formalism for the dosimetry of several electron beam energies. We employed electron beams with nominal energies of 4, 6, 9, 12, and 15 MeV of a Varian 2100C linear accelerator, an Exradin A12, and an Exradin P11 chamber for the analysis. The results showed differences below 3% when comparing the cylindrical chamber and alternative protocols with the parallel-plate chamber and the TRS-398 formalism for electron beams reference dosimetry. These results can bring confidence in using a cylindrical chamber for reference electron beam dosimetry, which can make the electron beam dosimetry procedure simpler and faster.

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References

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