Studying and analyzing the impact of upgrading the Elekta Preces Linear accelerator on the percentage depth dose parameters.

Abdurraouf M. Aghila; Saad S. Saad; Faraj A. Elmasrub; Ali A. Alrabee

doi:10.58916/jhas.v8i5.126

Authors

Abdurraouf M. Aghila Department of Physics, Faculty of Education (Tripoli), University of Tripoli, Tripoli, Libya Author
Saad S. Saad Institute of Medical Sciences and Technology, Abu-Salim, Tripoli, Libya Author
Faraj A. Elmasrub National Cancer Institute of Sabratha, Sabratha, Libya Author
Ali A. Alrabee Department of physics, Faculty of Education (Abuissa), University of Zawia, Zawia, Libya Author

DOI:

https://doi.org/10.58916/jhas.v8i5.126

Keywords:

PDD, MLC, SH collimator, surface dose, Elekta Preces Linac.

Abstract

The delivery of an accurate radiation dose to the tumor site, and thus the success of radiation treatment, depends on the accuracy of measurements of the radiation parameters. Therefore, this paper aimed to study and analyze the impact of upgrading the Electa Preces linear accelerator installed at the Radiotherapy department at Tripoli University Hospital, Tripoli, Libya, from a standard head collimator to a multileaf collimator on percentage depth dose (PDD) parameters for 6 MV and 15 MV photon beam energies at various field sizes and depths. The measurements in this study were carried out using a PTW MP3-M 3D water scanning system, and the acquired data were processed using MEPHYSTO mc²navigation software (PTW, Freiburg) version 1.6. The results of this paper showed considerable variations between the majority of parameters of PDD. The highest relative differences between the measured PDD pre- and post-upgrade were observed in the build-up region. The highest value recorded was 16.69% for 6 MV photon beam energy. Additionally, the relative deviation of surface dose reached 9.27% for photon beam energy. Therefore, recommissioning the collected data, which is used in the treatment planning system to evaluate dose distribution in patients, is needed and strongly recommended.

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