title: Monte Carlo photon beam modeling and commissioning for radiotherapy dose calculation algorithm.
abstract: The aim of the present work was a Monte Carlo verification of the Multi-grid superposition (MGS) dose calculation algorithm implemented in the CMS XiO (Elekta) treatment planning system and used to calculate the dose distribution produced by photon beams generated by the linear accelerator (linac) Siemens Primus. The BEAMnrc/DOSXYZnrc (EGSnrc package) Monte Carlo model of the linac head was used as a benchmark. In the first part of the work, the BEAMnrc was used for the commissioning of a 6 MV photon beam and to optimize the linac description to fit the experimental data. In the second part, the MGS dose distributions were compared with DOSXYZnrc using relative dose error comparison and γ-index analysis (2%/2 mm, 3%/3 mm), in different dosimetric test cases. Results show good agreement between simulated and calculated dose in homogeneous media for square and rectangular symmetric fields. The γ-index analysis confirmed that for most cases the MGS model and EGSnrc doses are within 3% or 3 mm.
authors.affiliation: Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, 2 Bd Frantz Fanon BP399 Alger RP, Algiers, Algeria. Electronic address: toutaoui.aek@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Toutaoui
authors.affiliation: Service de Radiothérapie, Centre Pierre et Marie Curie, 1 Rue Battandier Place du 1er Mai, Algiers, Algeria.
authors.forename: S
authors.initials: S
authors.lastname: Ait chikh
authors.affiliation: Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, 2 Bd Frantz Fanon BP399 Alger RP, Algiers, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Khelassi-Toutaoui
authors.affiliation: Service de Radiothérapie, Centre Anti-Cancer d'Oran, Oran, Algeria.
authors.forename: B
authors.initials: B
authors.lastname: Hattali
mesh_terms: D000465:Algorithms; D009010:Monte Carlo Method; D010315:Particle Accelerators; D019047:Phantoms, Imaging; D017785:Photons / Q000627:therapeutic use*; D011829:Radiation Dosage; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D014867:Water
chemical_list: D014867:Water
keywords: EGSnrc; Monte Carlo; TPS commissioning