scholarly journals Phantom design and dosimetric characterization for multiple simultaneous cell irradiations with active pencil beam scanning

2019 ◽  
Vol 58 (4) ◽  
pp. 563-573 ◽  
Author(s):  
Monika Clausen ◽  
Suphalak Khachonkham ◽  
Sylvia Gruber ◽  
Peter Kuess ◽  
Rolf Seemann ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Target Location ◽  
Reference Conditions ◽  
Absorbed Dose ◽  
Planning System ◽  
Treatment Planning System ◽  
Pencil Beam ◽  
Depth Dose

Abstract A new phantom was designed for in vitro studies on cell lines in horizontal particle beams. The phantom enables simultaneous irradiation at multiple positions along the beam path. The main purpose of this study was the detailed dosimetric characterization of the phantom which consists of various heterogeneous structures. The dosimetric measurements described here were performed under non-reference conditions. The experiment involved a CT scan of the phantom, dose calculations performed with the treatment planning system (TPS) RayStation employing both the Pencil Beam (PB) and Monte Carlo (MC) algorithms, and proton beam delivery. Two treatment plans reflecting the typical target location for head and neck cancer and prostate cancer treatment were created. Absorbed dose to water and dose homogeneity were experimentally assessed within the phantom along the Bragg curve with ionization chambers (ICs) and EBT3 films. LETd distributions were obtained from the TPS. Measured depth dose distributions were in good agreement with the Monte Carlo-based TPS data. Absorbed dose calculated with the PB algorithm was 4% higher than the absorbed dose measured with ICs at the deepest measurement point along the spread-out Bragg peak. Results of experiments using melanoma (SKMel) cell line are also presented. The study suggested a pronounced correlation between the relative biological effectiveness (RBE) and LETd, where higher LETd leads to elevated cell death and cell inactivation. Obtained RBE values ranged from 1.4 to 1.8 at the survival level of 10% (RBE10). It is concluded that dosimetric characterization of a phantom before its use for RBE experiments is essential, since a high dosimetric accuracy contributes to reliable RBE data and allows for a clearer differentiation between physical and biological uncertainties.

scholarly journals A benchmarking method to evaluate the accuracy of a commercial proton monte carlo pencil beam scanning treatment planning system

2017 ◽  
Vol 18 (2) ◽  
pp. 44-49 ◽  
Author(s):  
Liyong Lin ◽  
Sheng Huang ◽  
Minglei Kang ◽  
Petri Hiltunen ◽  
Reynald Vanderstraeten ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Treatment Planning ◽  
Planning System ◽  
Treatment Planning System ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Pencil Beam Scanning

Developing a Monte Carlo model for MEVION S250i with HYPERSCAN and Adaptive Aperture™ pencil beam scanning proton therapy system

2020 ◽  
pp. 1-8
Author(s):  
Bing-Hao Chiang ◽  
Austin Bunker ◽  
Hosang Jin ◽  
Salahuddin Ahmad ◽  
Yong Chen
Keyword(s):  
Monte Carlo ◽  
Proton Therapy ◽  
Monte Carlo Model ◽  
Particle Simulation ◽  
Planning System ◽  
Treatment Planning System ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Pencil Beam Scanning ◽  
Beam Characteristics

Abstract Aim: As the number of proton therapy facilities has steadily increased, the need for the tool to provide precise dose simulation for complicated clinical and research scenarios also increase. In this study, the treatment head of Mevion HYPERSCAN pencil beam scanning (PBS) proton therapy system including energy modulation system (EMS) and Adaptive Aperture™ (AA) was modelled using TOPAS (TOolkit for PArticle Simulation) Monte Carlo (MC) code and was validated during commissioning process. Materials and methods: The proton beam characteristics including integral depth doses (IDDs) of pristine Bragg peak and in-air beam spot sizes were simulated and compared with measured beam data. The lateral profiles, with and without AA, were also verified against calculation from treatment planning system (TPS). Results: All beam characteristics for IDDs and in-air spot size agreed well within 1 mm and 10% separately. The full width at half maximum and penumbra of lateral dose profile also agree well within 2 mm. Finding: The TOPAS MC simulation of the MEVION HYPERSCAN PBS proton therapy system has been modelled and validated; it could be a viable tool for research and verification of the proton treatment in the future.

scholarly journals Dosimetric characteristics of 6 MV photons from TrueBeam STx medical linear accelerator: simulation and experimental data

2019 ◽  
Vol 9 (2) ◽  
pp. 37-44
Author(s):  
N. D. Ton Ton ◽  
B. D. Linh Linh ◽  
Q.T. Pham Pham
Keyword(s):  
Monte Carlo ◽  
Particle Physics ◽  
Nuclear Physics ◽  
Planning System ◽  
Treatment Planning System ◽  
Linear Accelerators ◽  
Index Method ◽  
Beam Radiation ◽  
Depth Dose ◽  
Check Calculation

A TrueBeam STx is one of the most technologically advanced linear accelerators forradiotherapy and radiosurgery. The Monte Carlo simulation widely used in many applications in various fields such as nuclear physics, astrophysics, particle physics, and medicine. The Geant4/GATE Monte Carlo toolkit is developed for the simulation in imaging diagnostics, nuclear medicine, radiotherapy, and radiation biology to more accurately predict beam radiation dosimetry. In this work, we present the simulation results of the dosimetric characteristics of a 6 MV photon beam of TrueBeam STx medical LINAC using Monte Carlo Geant4/GATE. The percentage depth dose (PDD), central axis depth dose (Profile) have been simulated and compared with those measured in a water phantom for field sizes 10×10 cm2 via the gamma-index method. These results will permit to check calculation data given by the treatment planning system.

scholarly journals Evaluation of the usefulness of the electron Monte Carlo algorithm for planning radiotherapy with the use of electron beams

2016 ◽  
Vol 22 (3) ◽  
pp. 49-54
Author(s):  
Sandra Łukomska ◽  
Paweł Kukołowicz ◽  
Anna Zawadzka ◽  
Mariusz Gruda ◽  
Marta Giżyńska ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Electron Beams ◽  
Medical Physics ◽  
Reference Conditions ◽  
Monte Carlo Algorithm ◽  
Planning System ◽  
Treatment Planning System ◽  
Medical Systems ◽  
Polish Society ◽  
Calculation Grid

Abstract The aim of the study was to verify the accuracy of calculations of dose distributions for electron beams performed using the electron Monte Carlo (eMC) v.10.0.28 algorithm implemented in the Eclipse treatment planning system (Varian Medical Systems). Implementation of the objective of the study was carried out in two stages. In the first stage the influence of several parameters defined by the user on the calculation accuracy was assessed. After selecting a set of parameters for which the best results were obtained a series of tests were carried. The tests were carried out in accordance with the recommendations of the Polish Society of Medical Physics (PSMP). The calculation and measurement of dose rate under reference conditions for semi quadratic and shaped fields were compared by individual cut-outs. We compared the calculated and measured percent depth doses, profiles and output factors for beams with an energy of 6, 9, 12, 15 and 18 MeV, for semi quadratic fields and for three different SSDs 100, 110, and 120 cm. All tests were carried out for beams generated in the Varian 2300CD Clinac linear accelerator. The results obtained during the first stage of the study demonstrated that the highest compliance between the calculations and measurements were obtained for the mean statistical uncertainty equal to 1, and the parameter responsible for smoothing the statistical noise defined as medium. Comparisons were made showing similar compliance calculations and measurements for the calculation grid of 0.1 cm and 0.25 cm and therefore the remaining part of the study was carried out for these two grids. In stage 2 it was demonstrated that the use of calculation grid of 0.1 cm allows for greater compliance of calculations and measurements. For energy 12, 15 and 18 MeV discrepancies between calculations and measurements, in most cases, did not exceed the PSMP action levels. The biggest differences between measurements and calculations were obtained for 6 MeV energy, for smallest fields and large SSD distances. Despite these discrepancies between calculations the model was adopted for clinical use.

scholarly journals Automated Monte Carlo Simulation of Proton Therapy Treatment Plans

2016 ◽  
Vol 15 (6) ◽  
pp. NP35-NP46 ◽  
Author(s):  
Joost Mathijs Verburg ◽  
Clemens Grassberger ◽  
Stephen Dowdell ◽  
Jan Schuemann ◽  
Joao Seco ◽  
...  
Keyword(s):  
Monte Carlo ◽  
High Performance ◽  
Data Exchange ◽  
New Technologies ◽  
Planning System ◽  
Treatment Planning System ◽  
Pencil Beam ◽  
Verification Methods ◽  
Treatment Plans

Simulations of clinical proton radiotherapy treatment plans using general purpose Monte Carlo codes have been proven to be a valuable tool for basic research and clinical studies. They have been used to benchmark dose calculation methods, to study radiobiological effects, and to develop new technologies such as in vivo range verification methods. Advancements in the availability of computational power have made it feasible to perform such simulations on large sets of patient data, resulting in a need for automated and consistent simulations. A framework called MCAUTO was developed for this purpose. Both passive scattering and pencil beam scanning delivery are supported. The code handles the data exchange between the treatment planning system and the Monte Carlo system, which requires not only transfer of plan and imaging information but also translation of institutional procedures, such as output factor definitions. Simulations are performed on a high-performance computing infrastructure. The simulation methods were designed to use the full capabilities of Monte Carlo physics models, while also ensuring consistency in the approximations that are common to both pencil beam and Monte Carlo dose calculations. Although some methods need to be tailored to institutional planning systems and procedures, the described procedures show a general road map that can be easily translated to other systems.

Clinical validation of a GPU-based Monte Carlo dose engine of a commercial treatment planning system for pencil beam scanning proton therapy

2021 ◽  
Vol 88 ◽  
pp. 226-234
Author(s):  
Francesco Fracchiolla ◽  
Erik Engwall ◽  
Martin Janson ◽  
Fredrik Tamm ◽  
Stefano Lorentini ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Treatment Planning ◽  
Proton Therapy ◽  
Planning System ◽  
Treatment Planning System ◽  
Clinical Validation ◽  
Pencil Beam ◽  
Beam Scanning ◽  
Pencil Beam Scanning

scholarly journals Experimental validation of Monte Carlo based treatment planning system in bone density equivalent media

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Djeni Smilovic Radojcic ◽  
Bozidar Casar ◽  
David Rajlic ◽  
Manda Svabic Kolacio ◽  
Ignasi Mendez ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Bone Density ◽  
Treatment Planning ◽  
Absorbed Dose ◽  
Dose Calculation ◽  
Planning System ◽  
Treatment Planning System ◽  
Absorbed Doses ◽  
Calculation Algorithms ◽  
Dose Calculation Algorithms

AbstractIntroductionAdvanced, Monte Carlo (MC) based dose calculation algorithms, determine absorbed dose as dose to medium-in-medium (Dm,m) or dose to water-in-medium (Dw,m). Some earlier studies identified the differences in the absorbed doses related to the calculation mode, especially in the bone density equivalent (BDE) media. Since the calculation algorithms built in the treatment planning systems (TPS) should be dosimetrically verified before their use, we analyzed dose differences between two calculation modes for the Elekta Monaco TPS. We compared them with experimentally determined values, aiming to define a supplement to the existing TPS verification methodology.Materials and methodsIn our study, we used a 6 MV photon beam from a linear accelerator. To evaluate the accuracy of the TPS calculation approaches, measurements with a Farmer type chamber in a semi-anthropomorphic phantom were compared to those obtained by two calculation options. The comparison was made for three parts of the phantom having different densities, with a focus on the BDE part.ResultsMeasured and calculated doses were in agreement for water and lung equivalent density materials, regardless of the calculation mode. However, in the BDE part of the phantom, mean dose differences between the calculation options ranged from 5.7 to 8.3%, depending on the method used. In the BDE part of the phantom, neither of the two calculation options were consistent with experimentally determined absorbed doses.ConclusionsBased on our findings, we proposed a supplement to the current methodology for the verification of commercial MC based TPS by performing additional measurements in BDE material.

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