1
|
Beck L, De Sio C, Hugtenburg R, Velthuis J. Electron contamination suppression in transmission detectors for radiotherapy. Phys Med Biol 2023; 68:215014. [PMID: 37774712 DOI: 10.1088/1361-6560/acfec6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 09/29/2023] [Indexed: 10/01/2023]
Abstract
Objective.Higher energy and intensity radiotherapy beams are being used, in part, due to the increased spatial accuracy of treatments. However, higher intensity beams can result in a larger total dose error, motivating the increasing need for real-time dose monitoring. We are developing a thin, real-time upstream monolithic active pixel sensor based system for beam monitoring with excellent precision on measuring the beam shape. Here we present a method to additionally provide dosimetry by adding thin conversion material in strips to the surface of the detector, a grating structure.Approach.By modulating the thickness of the conversion material to minimally disturb the contamination electron signal while enhancing the photon signal, the difference in these signals can be used to extract a photon-only signal, and hence dose. The simulation software Gate, based on Geant4, is utilised to study whether well functioning gratings can be better made from aluminium or copper and to optimise the thickness of a copper grating.Main results.It is possible to enhance the photon signal by a factor 6.7 (7.7) compared to the bare sensor for a 5.8 (6.7) MV beam, without modulation of the signal due to beam electrons.Significance.The grating can be used to perform dosimetry in real-time using a thin upstream detector.
Collapse
Affiliation(s)
- Lana Beck
- University of Bristol, H.H. Wills Physics Laboratory, Tyndall Avenue, BS8 1TL, Bristol, United Kingdom
| | - Chiara De Sio
- University of Bristol, H.H. Wills Physics Laboratory, Tyndall Avenue, BS8 1TL, Bristol, United Kingdom
| | - Richard Hugtenburg
- University of Bristol, H.H. Wills Physics Laboratory, Tyndall Avenue, BS8 1TL, Bristol, United Kingdom
- Swansea University Medical School, Singleton Park, Swansea, United Kingdom
| | - Jaap Velthuis
- University of Bristol, H.H. Wills Physics Laboratory, Tyndall Avenue, BS8 1TL, Bristol, United Kingdom
- Swansea University Medical School, Singleton Park, Swansea, United Kingdom
| |
Collapse
|
2
|
Zuber SH, Hadi MFRA, Samson DO, Jayamani J, Rabaiee NA, Aziz MZA, Hashikin NAA, Ying CK, Yusof MFM, Hashim R. Dosimetric Analysis of Rhizophora-based Phantom Material in Radiation Therapy Applications Using Monte Carlo GATE Simulation. J Med Phys 2023; 48:358-364. [PMID: 38223797 PMCID: PMC10783191 DOI: 10.4103/jmp.jmp_75_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 09/05/2023] [Accepted: 09/23/2023] [Indexed: 01/16/2024] Open
Abstract
Purpose This study aims to determine the percentage depth dose (PDD) of a phantom material made from soy-lignin bonded Rhizophora spp. particleboard coated with a gloss finish by using Monte Carlo Geant4 Application for Tomographic Emission (GATE) simulation. Materials and Methods The particleboard was fabricated using a hot pressing technique at target density of 1.0 g·cm-3 and the elemental fraction was recorded for the simulation. The PDD was simulated in the GATE simulation using the linear accelerator Elekta Synergy model for the water phantom and Rhizophora phantom, and the results were compared with the experimental PDD performed by several studies. Beam flatness and beam symmetry were also measured in this study. Results The simulated PDD for Rhizophora and water was in agreement with the experimental PDD of water with overall discrepancies of 0% to 8.7% at depth ranging from 1.0 to 15.0 cm. In the GATE simulation, all the points passed the clinical 3%/3 mm criterion in comparison with water, with the final percentage of 2.34% for Rhizophora phantom and 2.49% for the water phantom simulated in GATE. Both the symmetries are all within the range of an acceptable value of 2.0% according to the recommendation, with the beam symmetry of the water phantom and Rhizophora phantom at 0.58% and 0.28%, respectively. Conclusions The findings of this study provide the necessary foundation to confidently use the phantom for radiotherapy purposes, especially in treatment planning.
Collapse
Affiliation(s)
- Siti Hajar Zuber
- Diagnostic Imaging and Radiotherapy, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 50300, Kuala Lumpur, Malaysia
| | | | | | | | - Nor Ain Rabaiee
- Department of Radiology, Kulliyyah of Medicine, International Islamic University Malaysia, 25200, Malaysia
| | - Mohd Zahri Abdul Aziz
- Oncology and Radiotherapy Unit, Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200, Malaysia
| | | | - Chee Keat Ying
- Oncology and Radiotherapy Unit, Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200, Malaysia
| | | | - Rokiah Hashim
- School of Industrial Technology, Universiti Sains Malaysia, 11800, Penang, Malaysia
| |
Collapse
|
3
|
Assalmi M, Diaf EY. Effect of the Gaussian distribution parameters of the electron beam generated at the target on the simulated x-ray dose. Biomed Phys Eng Express 2023; 9. [PMID: 36758237 DOI: 10.1088/2057-1976/acbaa0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/09/2023] [Indexed: 02/11/2023]
Abstract
The purpose of this work was to investigate by Monte Carlo method the adjustment of photon beams delivered by the medical LINear ACcelerator (LINAC) Elekta Synergy MLCi2. This study presents an optimization of the Gaussian distribution parameters of the accelerated electrons before the target simulated by two Monte Carlo codes and for three beams. The photon (x-ray) beam is produced by the interaction of accelerated electrons with the LINAC target. The electrons are accelerated by a potential difference created between the anode and the cathode of the gun and directed towards the target. In the Monte Carlo simulation, it is necessary to setup the spectrum parameters of the generated electrons to simulate the x-ray dose distribution. In this study, we modeled the LINAC geometry for photon beams 18MV and 6MV in cases Flattened (FF) and Flattening-Filter-Free (FFF). The Monte Carlo simulations are based on G4Linac_MT and GATE codes. The results of the optimized configurations determined after more than 20 tests for each beam energy show a very good agreement with the experimental measurements for different irradiation fields for the depth (PDD) and lateral (Profile) dose distribution. In all Monte Carlo calculations performed in this study, the statistical uncertainty is less than 2%. The results were also in very good agreement in terms ofγ-index analysis, for the 3%/3 mm and 2%/2 mm criteria.
Collapse
Affiliation(s)
- Mustapha Assalmi
- Laboratory of Biology, Geoscience, Physics and Environment (LBGPE), Multidisciplinary Faculty of Nador, Mohammed First University, Oujda, Morocco
| | - El Yamani Diaf
- Laboratory of Biology, Geoscience, Physics and Environment (LBGPE), Multidisciplinary Faculty of Nador, Mohammed First University, Oujda, Morocco
| |
Collapse
|
4
|
Thien TC, Nemallapudi MV, Hsieh CW, Chen AE. Uniformity calibration for large area XY strip parallel plate ionization chamber. Phys Med Biol 2022; 68. [PMID: 36562587 DOI: 10.1088/1361-6560/aca9b5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 12/07/2022] [Indexed: 12/12/2022]
Abstract
Demand for large area parallel plate ionization chamber (PPIC) or large area ionization chamber (LAIC) has risen in recent years due to several advantages of the large effective area in monitoring therapeutic radiation beams. PPICs are designed for the measurements of beam profile and dosimetry in radiation therapy quality assurance (QA) procedures.Objective. Heterogeneous responses over the large sensitive area pose an undeniable concern for the straightforward applications of PPICs in clinical dosimetry. Uniformity calibration for the detector response is thus essential for the accurate performance of each PPIC unit.Approach.A large area XY strip PPIC, characterized by a large effective area of 345.44 × 345.44 mm2and 256 readout channels, was investigated in this study. A new systematic uniformity calibration is developed to improve the lateral response of the PPIC over the measurements for both narrow beams and large square field beams. A 2D response map of the PPIC was obtained by a spot-scanning method using a compact x-ray tube (mini x-ray). The mini x-ray, providing stable radiation (uncertainty <0.1%), was moved with a step size of 20 mm in 2 dimensions across the entire PPIC surface to collect a complete spot scan. Different uniformity calibration methods were introduced for the measurement of the PPIC by adopting the information from the detector 2D response map.Main results.Deviation of the detector response, before calibration, was observed to reach about 7% for the testing PPIC unit which is much higher than the recommended uniformity response of 1% (IAEA TRS-398). The uniformity response of the PPIC improved significantly to less than 1% across the detector surface after calibration.Significance.The proposed methods enable the practical application of PPIC in routine clinical dosimetry and can be reliably adopted by any radiation facility to perform daily and monthly QA.
Collapse
Affiliation(s)
- T C Thien
- Department of Physics, National Central University, Taiwan.,Institute of Physics, Academia Sinica, Taiwan
| | | | - C W Hsieh
- Electrical Engineering, National Chiayi University, Taiwan
| | - A E Chen
- Department of Physics, National Central University, Taiwan
| |
Collapse
|
5
|
Aboulbanine Z, Bahhous K. Elaboration and experimental validation of a Monte Carlo source model for linac 6 MV photon beams with and without Flattening Filter. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
|
6
|
Chand B, Singh R, Kumar M. Determination and validation of the initial beam parameters of Elekta Agility collimator head by Monte Carlo simulations. Phys Eng Sci Med 2022; 45:889-899. [PMID: 35849322 DOI: 10.1007/s13246-022-01159-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 07/01/2022] [Indexed: 11/24/2022]
Abstract
The availability of geometrical, physical, and initial beam parameters for Monte Carlo (MC) simulations of the Elekta Agility collimator head has become very difficult due to the proprietary nature of this data. This study presents strategies to independently determine the geometrical and physical properties of the components and initial beam parameters of the Agility collimator head for full beam simulations and postulates a benchmarking process using the EGSnrc MC toolkit. Target material of W (90%) and Re (10%) of 0.09 cm thickness, flattening filter of 1.77 cm thick stainless steel placed on 0.5 cm Al disc, and primary and secondary collimators of Tungsten alloy have been found to best fit the Agility head. The initial beam energy of 6.0 MeV with a radial distribution given as full-width half maxima (FWHM) of 0.301 cm (crossline) × 0.201 cm (inline) for 6 MV beam with a mean angular spread of 1.34° has been found best fitting the model. Variations of 0.29% and 0.59% have been noted in the measured and calculated values of TPR20,10 and D10 respectively. More than 90% dose points for all simulations passed the 2D gamma criteria of 3% DD, 3 mm DTA. This MC model of the Agility head can be used for dose calculation and validation of advanced treatment techniques.
Collapse
Affiliation(s)
- Bhagat Chand
- Department of Physics, Lovely Professional University, Phagwara, 1444141, Punjab, India.,Department of Radiotherapy, Dr. Rajendra Prasad Government Medical College, Tanda, Kangra, 176001, Himachal Pradesh, India
| | - Ranjit Singh
- Department of Radiotherapy, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Mukesh Kumar
- Department of Physics, Lovely Professional University, Phagwara, 1444141, Punjab, India.
| |
Collapse
|
7
|
|
8
|
Castle JR, Duan J, Feng X, Chen Q. Development of a virtual source model for Monte Carlo-based independent dose calculation for varian linac. J Appl Clin Med Phys 2022; 23:e13556. [PMID: 35138686 PMCID: PMC9121055 DOI: 10.1002/acm2.13556] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/05/2022] [Accepted: 01/26/2022] [Indexed: 11/10/2022] Open
Abstract
Monte Carlo (MC) independent dose calculations are often based on phase-space files (PSF), as they can accurately represent particle characteristics. PSF generally are large and create a bottleneck in computation time. In addition, the number of independent particles is limited by the PSF, preventing further reduction of statistical uncertainty. The purpose of this study is to develop and validate a virtual source model (VSM) to address these limitations. Particles from existing PSF for the Varian TrueBeam medical linear accelerator 6X, 6XFFF, 10X, and 10XFFF beam configurations were tallied, analyzed, and used to generate a dual-source photon VSM that includes electron contamination. The particle density distribution, kinetic energy spectrum, particle direction, and the correlations between characteristics were computed. The VSM models for each beam configuration were validated with water phantom measurements as well as clinical test cases against the original PSF. The new VSM requires 67 MB of disk space for each beam configuration, compared to 50 GB for the PSF from which they are based and effectively remove the bottleneck set by the PSF. At 3% MC uncertainty, the VSM approach reduces the calculation time by a factor of 14 on our server. MC doses obtained using the VSM approach were compared against PSF-generated doses in clinical test cases and measurements in a water phantom using a gamma index analysis. For all tests, the VSMs were in excellent agreement with PSF doses and measurements (>90% passing voxels between doses and measurements). Results of this study indicate the successful derivation and implementation of a VSM model for Varian Linac that significantly saves computation time without sacrificing accuracy for independent dose calculation.
Collapse
Affiliation(s)
| | - Jingwei Duan
- Department of Radiation Medicine, University of Kentucky School of Medicine, Lexington, Kentucky, USA
| | - Xue Feng
- Carina Medical LLC, Lexington, Kentucky, USA
| | - Quan Chen
- Department of Radiation Medicine, University of Kentucky School of Medicine, Lexington, Kentucky, USA
| |
Collapse
|
9
|
Yang HJ, Kim TH, Schaarschmidt T, Park DW, Kang SH, Chung HT, Suh TS. A multivariate approach to determine electron beam parameters for a Monte Carlo 6 MV Linac model: Statistical and machine learning methods. Phys Med 2021; 93:38-45. [PMID: 34920381 DOI: 10.1016/j.ejmp.2021.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 11/28/2021] [Accepted: 12/07/2021] [Indexed: 11/28/2022] Open
Abstract
PURPOSE This study aimed to determine the optimal initial electron beam parameters of a Linac for radiotherapy with a multivariate approach using statistical and machine-learning tools. METHODS For MC beam commissioning, a 6 MV Varian Clinac was simulated using the Geant4 toolkit. The authors investigated the relations between simulated dose distribution and initial electron beam parameters, namely, mean energy (E), energy spread (ES), and radial beam size (RS). The goodness of simulation was evaluated by the slope of differences between the simulated and the golden beam data. The best-fit combination of the electron beam parameters that minimized the slope of dose difference was searched through multivariate methods using conventional statistical methods and machine-learning tools of the scikit-learn library. RESULTS Simulation results with 87 combinations of the electron beam parameters were analyzed. Regardless of being univariate or multivariate, traditional statistical models did not recommend a single parameter set simultaneously minimizing slope of dose differences for percent depth dose (PDD) and lateral dose profile (LDP). Two machine learning classification modules, RandomForestClassifier and BaggingClassifier, agreed in recommending (E = 6.3 MeV, ES = ±5.0%, RS = 1.0 mm) for predicting simultaneous acceptance of PDD and LDP. CONCLUSIONS The machine learning with random-forest and bagging classifier modules recommended a consistent result. It was possible to draw an optimal electron beam parameter set using multivariate methods for MC simulation of a radiotherapy 6 MV Linac.
Collapse
Affiliation(s)
- Hye Jeong Yang
- Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Tae Hoon Kim
- Department of Nuclear Engineering, Hanyang University College of Engineering, Seoul, Republic of Korea
| | - Thomas Schaarschmidt
- Department of Nuclear Engineering, Hanyang University College of Engineering, Seoul, Republic of Korea
| | - Dong-Wook Park
- Department of Radiation Oncology, Ilsan Paik Hospital, Goyang, Republic of Korea
| | - Seung Hee Kang
- Department of Radiation Oncology, Ilsan Paik Hospital, Goyang, Republic of Korea
| | - Hyun-Tai Chung
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Republic of Korea.
| | - Tae Suk Suh
- Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
| |
Collapse
|
10
|
Dose divergence between monte carlo simulation and experimental measurements in the build-up region for a photon beam. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
11
|
Park H, Paganetti H, Schuemann J, Jia X, Min CH. Monte Carlo methods for device simulations in radiation therapy. Phys Med Biol 2021; 66:10.1088/1361-6560/ac1d1f. [PMID: 34384063 PMCID: PMC8996747 DOI: 10.1088/1361-6560/ac1d1f] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/12/2021] [Indexed: 11/12/2022]
Abstract
Monte Carlo (MC) simulations play an important role in radiotherapy, especially as a method to evaluate physical properties that are either impossible or difficult to measure. For example, MC simulations (MCSs) are used to aid in the design of radiotherapy devices or to understand their properties. The aim of this article is to review the MC method for device simulations in radiation therapy. After a brief history of the MC method and popular codes in medical physics, we review applications of the MC method to model treatment heads for neutral and charged particle radiation therapy as well as specific in-room devices for imaging and therapy purposes. We conclude by discussing the impact that MCSs had in this field and the role of MC in future device design.
Collapse
Affiliation(s)
- Hyojun Park
- Department of Radiation Convergence Engineering, Yonsei University, Wonju, Republic of Korea
| | - Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Xun Jia
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75235, United States of America
| | - Chul Hee Min
- Department of Radiation Convergence Engineering, Yonsei University, Wonju, Republic of Korea
| |
Collapse
|
12
|
Leste J, Younes T, Chauvin M, Franceries X, Delbaere A, Vieillevigne L, Ferrand R, Bardies M, Simon L. Technical note: GAMMORA, a free, open-source, and validated GATE-based model for Monte-Carlo simulations of the Varian TrueBeam. Phys Med 2021; 89:211-218. [PMID: 34416389 DOI: 10.1016/j.ejmp.2021.07.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/30/2021] [Accepted: 07/31/2021] [Indexed: 10/20/2022] Open
Abstract
PURPOSE Monte Carlo (MC) is the reference computation method for medical physics. In radiotherapy, MC computations are necessary for some issues (such as assessing figures of merit, double checks, and dose conversions). A tool based on GATE is proposed to easily create full MC simulations of the Varian TrueBeam STx. METHODS GAMMORA is a package that contains photon phase spaces as a pre-trained generative adversarial network (GAN) and the TrueBeam's full geometry. It allows users to easily create MC simulations for simple or complex radiotherapy plans such as VMAT. To validate the model, the characteristics of generated photons are first compared to those provided by Varian (IAEA format). Simulated data are also compared to measurements in water and heterogeneous media. Simulations of 8 SBRT plans are compared to measurements (in a phantom). Two examples of applications (a second check and interplay effect assessment) are presented. RESULTS The simulated photons generated by the GAN have the same characteristics (energy, position, and direction) as the IAEA data. Computed dose distributions of simple cases (in water) and complex plans delivered in a phantom are compared to measurements, and the Gamma index (3%/3mm) was always superior to 98%. The feasibility of both clinical applications is shown. CONCLUSIONS This model is now shared as a free and open-source tool that generates radiotherapy MC simulations. It has been validated and used for five years. Several applications can be envisaged for research and clinical purposes.
Collapse
Affiliation(s)
- Jeremy Leste
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France
| | - Tony Younes
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France
| | - Maxime Chauvin
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France
| | - Xavier Franceries
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France
| | - Alexia Delbaere
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France
| | - Laure Vieillevigne
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France; Institut Claudius Regaud (ICR), Institut Universitaire du Cancer de Toulouse-Oncopole (IUCT-O), Departement Ingenierie Physique Medicale, Toulouse, France
| | | | - Manuel Bardies
- Cancer Research Institute of Montpellier, U1194 INSERM/ICM/Montpellier University, and Cancer Institute of Montpellier, Montpellier, France
| | - Luc Simon
- Centre de Recherches en Cancerologie de Toulouse (CRCT), Universite de Toulouse, UPS, INSERM, Toulouse, France; Institut Claudius Regaud (ICR), Institut Universitaire du Cancer de Toulouse-Oncopole (IUCT-O), Departement Ingenierie Physique Medicale, Toulouse, France.
| |
Collapse
|
13
|
Krim DE, Bakari D, Zerfaoui M, Rrhioua A. Implementation of a new virtual source model in Gate 9.0 package to simulate Elekta Synergy MLCi2 6 MV accelerator. Biomed Phys Eng Express 2021; 7. [PMID: 34193645 DOI: 10.1088/2057-1976/ac1057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 06/30/2021] [Indexed: 11/11/2022]
Abstract
Monte Carlo simulation is appreciated as an extraordinary technique to investigate particle physic processes in Radiation Therapy. This task offers a new Virtual Source Model (VSM) based on an innovative reconstruction method to extract energy and angular distribution from the Python phase space output data. Extensive comparisons of dose distributions are performed to evaluate VSM simulation precision. Four squared field configurations extending from 3 × 3 to 20 × 20 cm2are chosen for dose calculation to test field size and symmetry influences. To evaluate simulation accuracy, the beam quality parameters (such asD10(%),dmax(cm),d80(cm), andTPR(20/10)) also validation tests (gamma index formalism for 2%/2 mm criteria, Distance To Agreement DTA, and the estimator standard error (ϵ,ϵmax)) are determined. Good agreement is achieved in terms of beam quality parameters and validation tests for each evaluated beam size, within a computation time of 58 hours and 17 hours on 20 nodes (presents 160 CPUs) of the full simulation and the VSM, respectively. This advanced VSM generated for the Elekta Synergy MLCi2 platform displays an uncomplicated approach. It is a great example of reconstructing different x-ray beams of various linac accelerators to facilitate its integration in cancer treatment.
Collapse
Affiliation(s)
- Deae-Eddine Krim
- Laboratory of Physics of Matter and Radiation Faculty of Sciences, Mohammed first University Oujda, Morocco
| | - Dikra Bakari
- National School of Applied Sciences, Mohammed first University, Oujda, Morocco
| | - Mustapha Zerfaoui
- Laboratory of Physics of Matter and Radiation Faculty of Sciences, Mohammed first University Oujda, Morocco
| | - Abdeslem Rrhioua
- Laboratory of Physics of Matter and Radiation Faculty of Sciences, Mohammed first University Oujda, Morocco
| |
Collapse
|
14
|
Ruiz Boiset G, V S Batista D, Coutinho Cardoso S. Clinical verification of treatment planning dose calculation in lung SBRT with GATE Monte Carlo simulation code. Phys Med 2021; 87:1-10. [PMID: 34091196 DOI: 10.1016/j.ejmp.2021.05.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 05/04/2021] [Accepted: 05/21/2021] [Indexed: 12/31/2022] Open
Abstract
PURPOSE This study aims to use GATE/Geant4 simulation code to evaluate the performance of dose calculations with Anisotropic Analytical Algorithm (AAA) in the context of lung SBRT for complex treatments considering images of patients. METHODS Four cases of non-small cell lung cancer treated with SBRT were selected for this study. Irradiation plans were created with AAA and recalculated end to end using Monte Carlo (MC) method maintaining field configurations identical to the original plans. Each treatment plan was evaluated in terms of PTV and organs at risk (OARs) using dose-volume histograms (DVH). Dosimetric parameters obtained from DVHs were used to compare AAA and MC. RESULTS The comparison between the AAA and MC DVH using gamma analysis with the passing criteria of 3%/3% showed an average passing rate of more than 90% for the PTV structure and 97% for the OARs. Tightening the criteria to 2%/2% showed a reduction in the average passing rate of the PTV to 86%. The agreement between the AAA and MC dose calculations for PTV dosimetric parameters (V100; V90; Homogeneity index; maximum, minimum and mean dose; CIPaddick and D2cm) was within 18.4%. For OARs, the biggest differences were observed in the spinal cord and the great vessels. CONCLUSIONS In general, we did not find significant differences between AAA and MC. The results indicate that AAA could be used in complex SBRT cases that involve a larger number of small treatment fields in the presence of tissue heterogeneities.
Collapse
Affiliation(s)
- Gisell Ruiz Boiset
- Instituto de Fı́sica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Delano V S Batista
- Instituto de Radioproteção e Dosimetria, IRD/CNEN, Rio de Janeiro, Brazil; Oncologia D'Or São Cristóvão, Rede D'Or São Luiz, Rio de Janeiro, Brazil
| | | |
Collapse
|
15
|
Sarrut D, Etxebeste A, Krah N, Létang JM. Modeling complex particles phase space with GAN for Monte Carlo SPECT simulations: a proof of concept. Phys Med Biol 2021; 66:055014. [PMID: 33477121 DOI: 10.1088/1361-6560/abde9a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A method is proposed to model by a generative adversarial network the distribution of particles exiting a patient during Monte Carlo simulation of emission tomography imaging devices. The resulting compact neural network is then able to generate particles exiting the patient, going towards the detectors, avoiding costly particle tracking within the patient. As a proof of concept, the method is evaluated for single photon emission computed tomography (SPECT) imaging and combined with another neural network modeling the detector response function (ARF-nn). A complete rotating SPECT acquisition can be simulated with reduced computation time compared to conventional Monte Carlo simulation. It also allows the user to perform simulations with several imaging systems or parameters, which is useful for imaging system design.
Collapse
Affiliation(s)
- D Sarrut
- Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Centre Léon Bérard 69373, France
| | | | | | | |
Collapse
|
16
|
Shi M, Myronakis M, Jacobson M, Ferguson D, Williams C, Lehmann M, Baturin P, Huber P, Fueglistaller R, Lozano IV, Harris T, Morf D, Berbeco RI. GPU-accelerated Monte Carlo simulation of MV-CBCT. Phys Med Biol 2020; 65:235042. [PMID: 33263311 DOI: 10.1088/1361-6560/abaeba] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Monte Carlo simulation (MCS) is one of the most accurate computation methods for dose calculation and image formation in radiation therapy. However, the high computational complexity and long execution time of MCS limits its broad use. In this paper, we present a novel strategy to accelerate MCS using a graphic processing unit (GPU), and we demonstrate the application in mega-voltage (MV) cone-beam computed tomography (CBCT) simulation. A new framework that generates a series of MV projections from a single simulation run is designed specifically for MV-CBCT acquisition. A Geant4-based GPU code for photon simulation is incorporated into the framework for the simulation of photon transport through a phantom volume. The FastEPID method, which accelerates the simulation of MV images, is modified and integrated into the framework. The proposed GPU-based simulation strategy was tested for its accuracy and efficiency in a Catphan 604 phantom and an anthropomorphic pelvis phantom with beam energies at 2.5 MV, 6 MV, and 6 MV FFF. In all cases, the proposed GPU-based simulation demonstrated great simulation accuracy and excellent agreement with measurement and CPU-based simulation in terms of reconstructed image qualities. The MV-CBCT simulation was accelerated by factors of roughly 900-2300 using an NVIDIA Tesla V100 GPU card against a 2.5 GHz AMD Opteron™ Processor 6380.
Collapse
Affiliation(s)
- Mengying Shi
- Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA, United States of America. Brigham and Women's Hospital, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA, United States of America
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Tang W, Tang B, Li X, Wang Y, Li Z, Gao Y, Gao H, Yan C, Sun L. Cellular S-value evaluation based on real human cell models using the GATE MC package. Appl Radiat Isot 2020; 168:109509. [PMID: 33214023 DOI: 10.1016/j.apradiso.2020.109509] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 10/28/2020] [Accepted: 11/06/2020] [Indexed: 11/25/2022]
Abstract
Exploring the spatial distribution of the energy loss of ionising radiation at the subcellular level is indispensable for evaluating the radiobiological effects of targeted radionuclide therapy accurately. Believing that S-values are important for obtaining the target dose, the Committee on Medical Internal Radiation Dose (MIRD) proposed a method to obtain the cellular dosimetric parameter. However, most available data on cellular S-values were calculated based on simple geometric models, such as ellipsoids or spheres, which do not accurately reflect biological reality. To investigate the influence of the cellular model on S-values, calculations were performed for two kinds of polygon-surface phantom models of realistic, individual human cells, the lung epithelial cell model (the B2B Phantom model) and the hepatocyte model (the Liver Phantom model), using the Monte Carlo (MC) software package GATE. To analyse the influence of cell geometry on the final S-value, the differences in the S-values between the realistic cell models and simple geometric sphere and ellipsoid models with similar volumes were calculated and compared for six different combinations of source and target regions. The irradiation conditions were 0.01-1.10 MeV monoenergetic electron sources and the Auger electronic therapy nuclides Ga-67, Tc-99m, In-111, I-125 and Tl-201, which are commonly used in nuclear medicine. The S-values calculated in this study are different from the results of the simple geometry models proposed by previous researchers. Two more precise polygon-surface phantom models of realistic, individual human cells were used, which provided more accurate information about the cell dose and will be very useful for the diagnostic application of radiotherapy in the future.
Collapse
Affiliation(s)
- Wei Tang
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Bo Tang
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China; Department of Radiation Protection Safety, Shandong Center for Disease Control and Prevention, Jinan, 250014, China
| | - Xiang Li
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Yidi Wang
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Zhanpeng Li
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Yunan Gao
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Han Gao
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Congchong Yan
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China
| | - Liang Sun
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, China.
| |
Collapse
|
18
|
Mustapha A, Yamani DE, Najim M. Validation of Monte carlo Geant4 multithreading code for a 6 MV photon beam of varian linac on the grid computing. Rep Pract Oncol Radiother 2020; 25:1001-1010. [PMID: 33132765 DOI: 10.1016/j.rpor.2020.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/28/2020] [Accepted: 09/16/2020] [Indexed: 10/23/2022] Open
Abstract
Aim To evaluate the computation time efficiency of the multithreaded code (G4Linac-MT) in the dosimetry application, using the high performance of the HPC-Marwan grid to determine with high accuracy the initial parameters of the 6 MV photon beam of Varian CLINAC 2100C. Background The difficulty of Monte Carlo methods is the long computation time, this is one of the disadvantages of the Monte Carlo methods. Materials and methods Calculations are performed by the multithreaded code G4Linac-MT and Geant4.10.04.p02 using the HPC-Marwan computing grid to evaluate the computing speed for each code. The multithreaded version is tested in several CPUs to evaluate the computing speed according to the number of CPUs used. The results were compared to the measurements using different types of comparisons, TPR20.10, penumbra, mean dose error and gamma index. Results The results obtained for this work indicate a much higher computing time saving for the G4Linac-MT version compared to the Geant4.10.04 version, the computing time decreases with the number of CPUs used, can reach about 12 times if 64CPUs are used. After optimization of the initial electron beam parameters, the results of the dose simulations obtained for this work are in very good agreement with the experimental measurements with a mean dose error of up to 0.41% on the PDDs and 1.79% on the lateral dose. Conclusions The gain in computation time leads us to perform Monte Carlo simulations with a large number of events which gives a high accuracy of the dosimetry results obtained in this work.
Collapse
Affiliation(s)
- Assalmi Mustapha
- Physics Team, Lab: OLMAN-RL, Multidisciplinary Faculty of Nador, University Mohammed First Oujda, Morocco
| | - Diaf El Yamani
- Physics Team, Lab: OLMAN-RL, Multidisciplinary Faculty of Nador, University Mohammed First Oujda, Morocco
| | - Mansour Najim
- Faculty of Science and Technical, Errachidia, Morocco
| |
Collapse
|
19
|
Gholami S, Longo F, Shahzadeh S, Nedaie HA, Sharp R, S Meigooni A. Normal lung tissue complication probability in MR-Linac and conventional radiotherapy. Rep Pract Oncol Radiother 2020; 25:961-968. [PMID: 33100912 DOI: 10.1016/j.rpor.2020.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/10/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose To study normal lung tissue (NLT) complications in magnetic resonance (MR) image based linac and conventional radiotherapy (RT) techniques. Materials and Methods The Geant4 toolkit was used to simulate a 6 MV photon beam. A homogenous magnetic field of 1.5 Tesla (T) was applied in both perpendicular and parallel directions relative to the radiation beam.Analysis of the NLT complications was assessed according to the normal lung tissue complication probability (NTCP), the mean lung dose (MLD), and percentage of the lung volume receiving doses greater than 20 Gy (V20), using a sample set of CT images generated from a commercially available 4D-XCAT digital phantom. Results The results show that the MLD and V20 were lower for MR-linac RT. The largest reduction of MLD and V20 for MR-linac RT configurations were 5 Gy and 29.3%, respectively. Conclusion MR-linac RT may result in lower NLT complications when compared to conventional RT.
Collapse
Affiliation(s)
- Somayeh Gholami
- Radiation Oncology Research Centre, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.,Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
| | - Francesco Longo
- Department of Physics, University of Trieste and INFN Trieste, Italy
| | - Sara Shahzadeh
- Department of Medical Radiation Engineering, Shahid Beheshti University, Tehran, Iran
| | - Hassan Ali Nedaie
- Radiation Oncology Research Centre, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.,Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
| | - Ryan Sharp
- Department of Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, Nevada, United States
| | - Ali S Meigooni
- Comprehensive Cancer Centers of Nevada, Las Vegas, Nevada, United States
| |
Collapse
|
20
|
Abolaban FA, Taha EM. Representation and illustration of the initial parameters in GATE 8.1 monte carlo simulation of an Elekta Versa-HD linear accelerator. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2020. [DOI: 10.1080/16878507.2020.1820271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Fouad A. Abolaban
- King Abdulaziz University, College of Engineering, Nuclear Engineering Department, Jeddah, Kingdom of Saudi Arabia, Jeddah, Saudi Arabia
| | - Eslam M. Taha
- King Abdulaziz University, College of Engineering, Nuclear Engineering Department, Jeddah, Kingdom of Saudi Arabia, Jeddah, Saudi Arabia
| |
Collapse
|
21
|
Shi M, Myronakis M, Jacobson M, Lehmann M, Ferguson D, Baturin P, Huber P, Fueglistaller R, Harris T, Lozano IV, Williams C, Morf D, Berbeco RI. A rapid, accurate image simulation strategy for mega-voltage cone-beam computed tomography. ACTA ACUST UNITED AC 2020; 65:135004. [DOI: 10.1088/1361-6560/ab868a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
22
|
Grevillot L, Boersma DJ, Fuchs H, Aitkenhead A, Elia A, Bolsa M, Winterhalter C, Vidal M, Jan S, Pietrzyk U, Maigne L, Sarrut D. Technical Note: GATE‐RTion: a GATE/Geant4 release for clinical applications in scanned ion beam therapy. Med Phys 2020; 47:3675-3681. [DOI: 10.1002/mp.14242] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/15/2020] [Accepted: 05/03/2020] [Indexed: 11/09/2022] Open
Affiliation(s)
- L. Grevillot
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - D. J. Boersma
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
- ACMIT Gmbh Viktor‐Kaplan‐Straße 2/1A‐2700Wiener Neustadt Austria
| | - H Fuchs
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
- Medical University of Vienna Vienna Austria
- Department of Radiation Therapy Medical University of Vienna/AKH Vienna Vienna Austria
| | - A. Aitkenhead
- Division of Cancer Sciences University of ManchesterManchester Cancer Research CentreThe Christie NHS Foundation Trust Manchester UK
| | - A. Elia
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - M. Bolsa
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - C. Winterhalter
- Division of Cancer Sciences University of ManchesterThe Christie NHS Foundation Trust Manchester UK
| | - M. Vidal
- Centre Antoine LACASSAGNE Université Côte d’Azur – Fédération Claude Lalanne Nice France
| | - S. Jan
- UMR BioMaps CEACNRSInsermUniversité Paris‐Saclay 4 place du Général Leclerc91401Orsay France
| | | | - L. Maigne
- Université Clermont AuvergneCNRS/IN2P3Laboratoire de Physique de Clermont, UMR6533 4 avenue Blaise Pascal TSA 60026 CS60026 63178Aubière cedex France
| | - D. Sarrut
- Université de LyonCREATISCNRS UMR5220Inserm U1044INSA‐LyonUniversité Lyon 1 Lyon France
| |
Collapse
|
23
|
Kim Y, Yi C, Kim I, Kim B, Kim J, Seong Y, Kim H. Monte Carlo studies on dose conversion factors from graphite to water for high energy X-ray beams. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
24
|
Adam DP, Liu T, Caracappa PF, Bednarz BP, Xu XG. New capabilities of the Monte Carlo dose engine ARCHER-RT: Clinical validation of the Varian TrueBeam machine for VMAT external beam radiotherapy. Med Phys 2020; 47:2537-2549. [PMID: 32175615 DOI: 10.1002/mp.14143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The Monte Carlo radiation transport method is considered the most accurate approach for absorbed dose calculations in external beam radiation therapy. In this study, an efficient and accurate source model of the Varian TrueBeam 6X STx Linac is developed and integrated with a fast Monte Carlo photon-electron transport absorbed dose engine, ARCHER-RT, which is capable of being executed on CPUs, NVIDIA GPUs, and AMD GPUs. This capability of fast yet accurate radiation dose calculation is essential for clinical utility of this new technology. This paper describes the software and algorithmic developments made to the ARCHER-RT absorbed dose engine. METHODS AMD's Heterogeneous-Compute Interface for Portability (HIP) was implemented in ARCHER-RT to allow for device independent execution on NVIDIA and AMD GPUs. Architecture-specific atomic-add algorithms have been identified and both more accurate single-precision and double-precision computational absorbed dose calculation methods have been added to ARCHER-RT and validated through a test case to evaluate the accuracy and performance of the algorithms. The validity of the source model and the radiation transport physics were benchmarked against Monte Carlo simulations performed with EGSnrc. Secondary dose-check physics plans, and a clinical prostate treatment plan were calculated to demonstrate the applicability of the platform for clinical use. Absorbed dose difference maps and gamma analyses were conducted to establish the accuracy and consistency between the two Monte Carlo models. Timing studies were conducted on a CPU, an NVIDIA GPU, and an AMD GPU to evaluate the computational speed of ARCHER-RT. RESULTS Percent depth doses were computed for different field sizes ranging from 1.5 cm2 × 1.5 cm2 to 22 cm2 × 40cm2 and the two codes agreed for all points outside high gradient regions within 3%. Axial profiles computed for a 10 cm2 × 10 cm2 field for multiple depths agreed for all points outside high gradient regions within 2%. The test case investigating the impact of native single-precision compared to double-precision showed differences in voxels as large as 71.47% and the implementation of KAS single-precision reduced the difference to less than 0.01%. The 3%/3mm gamma pass rates for an MPPG5a multileaf collimator (MLC) test case and a clinical VMAT prostate plan were 94.2% and 98.4% respectively. Timing studies demonstrated the calculation of a VMAT plan was completed in 50.3, 187.9, and 216.8 s on an NVIDIA GPU, AMD GPU, and Intel CPU, respectively. CONCLUSION ARCHER-RT is capable of patient-specific VMAT external beam photon absorbed dose calculations and its potential has been demonstrated by benchmarking against a well validated EGSnrc model of a Varian TrueBeam. Additionally, the implementation of AMD's HIP has shown the flexibility of the ARCHER-RT platform for device independent calculations. This work demonstrates the significant addition of functionality added to ARCHER-RT framework which has marked utility for both research and clinical applications and demonstrates further that Monte Carlo-based absorbed dose engines like ARCHER-RT have the potential for widespread clinical implementation.
Collapse
Affiliation(s)
- David P Adam
- Medical Physics, University of Wisconsin Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
| | - Tianyu Liu
- Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA
| | | | - Bryan P Bednarz
- Medical Physics, University of Wisconsin Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
| | - Xie George Xu
- Nuclear Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA
| |
Collapse
|
25
|
Wu T, Liu W, Fan T, Zhong H, Zhou H, Guo W, Zhu X. 5-Androstenediol prevents radiation injury in mice by promoting NF-κB signaling and inhibiting AIM2 inflammasome activation. Biomed Pharmacother 2019; 121:109597. [PMID: 31726369 DOI: 10.1016/j.biopha.2019.109597] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/22/2019] [Accepted: 10/26/2019] [Indexed: 02/06/2023] Open
Abstract
In the present study, the therapeutic effects of 5-androstenediol on radiation-induced myeloid suppression and tissue damage in mice and the possible mechanism were explored. The mice were subjected to whole-body irradiation, and 5-androstenediol was administered subcutaneously at different times and doses. The evaluation of the survival rate showed that the administration of 5-androstenediol every three days post-irradiation was the most effective in decreasing the death of the mice. Additionally, 5-androstenediol dose-dependently reduced the death caused by 9 Gy radiation. The pharmacological mechanism was investigated by blood analysis, western blot analysis, immunofluorescence and immunohistochemistry. 5-Androstenediol significantly ameliorated myeloid suppression, as demonstrated by elevated levels of total white blood cells, including neutrophils and platelets, in the peripheral blood. By H&E staining, we found that radiation-induced myeloid suppression in the bone marrow and spleen, as well as tissue damage in the lung and colon, was significantly ameliorated by treatment with 5-androstenediol. Immunohistochemistry showed elevated phosphorylation of p65 in the bone marrow and spleen, indicating the activation of NF-κB signaling. Moreover, 5-androstenediol markedly hampered the radiation-induced activation of caspase-1 and GSDMD in the colon by decreasing the interaction between AIM2 and ASC. Taken together, our results suggest that, by promoting NF-κB signaling and inhibiting inflammasome-mediated pyroptosis, 5-androstenediol can be used as a radioprotective drug.
Collapse
Affiliation(s)
- Tiancong Wu
- Jinling Hospital, Department of Radiation Oncology, Nanjing University, School Medicine, Nanjing, 210002, PR China
| | - Wen Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, PR China
| | - Ting Fan
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, PR China
| | - Haiqing Zhong
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, PR China
| | - Han Zhou
- Jinling Hospital, Department of Radiation Oncology, Nanjing University, School Medicine, Nanjing, 210002, PR China
| | - Wenjie Guo
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, PR China.
| | - Xixu Zhu
- Jinling Hospital, Department of Radiation Oncology, Nanjing University, School Medicine, Nanjing, 210002, PR China.
| |
Collapse
|
26
|
Martins JC, Saxena R, Neppl S, Alhazmi A, Reiner M, Veloza S, Belka C, Parodi K. Optimization of Phase Space files from clinical linear accelerators. Phys Med 2019; 64:54-68. [PMID: 31515036 DOI: 10.1016/j.ejmp.2019.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 06/05/2019] [Accepted: 06/15/2019] [Indexed: 10/26/2022] Open
Abstract
This work proposes a methodology to produce an optimized phase-space (PhSp) for the Elekta Synergy linac by tuning the energy and direction of particles inside the 6-MV Elekta Precise PhSp, provided by the International Atomic Energy Agency (IAEA), for Monte Carlo (MC) simulations. First, the energies of the particles emerging from the original PhSp were increased by different factors, producing new PhSps. Percentage depth dose (PDD) profiles were simulated and compared to measured data from a Synergy linac for 6-MV photon beam. This process was repeated until a minimum difference was reached. Particles' directions were then manipulated following identified correlations to lateral profiles, resulting in two distinct perturbation factors based on inline and crossline profiles. Both factors were merged into one single optimal factor. For energy optimization, an increase of 0.32 MeV applied to all particles inside the original PhSp, but to 0.511 MeV annihilation photons, provided the best results. The direction optimization factor was the combination of the individual factors for inline (0.605%) and crossline (0.051%). The agreement between measured and simulated profiles, when using the optimized PhSp, improved considerably in comparison to simulations performed with the original IAEA PhSp. For all fields and depths analyzed, the discrepancies for PDD, inline and crossline profiles dropped from 11.2%, 15.7% and 27.5% to under 1.4%, 4.7% and 13.2%, respectively. The optimized PhSp should not replace the full linac modelling, however it offers an alternative for MC dose calculations when neither geometric details nor validated IAEA PhSp are available to the user.
Collapse
Affiliation(s)
- Juliana Cristina Martins
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching b. München, Germany.
| | - Rangoli Saxena
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching b. München, Germany.
| | - Sebastian Neppl
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße15, 81377 Munich, Germany.
| | - Abdulaziz Alhazmi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching b. München, Germany.
| | - Michael Reiner
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße15, 81377 Munich, Germany.
| | - Stella Veloza
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching b. München, Germany.
| | - Claus Belka
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße15, 81377 Munich, Germany; German Cancer Consortium (DKTK), Pettenkoferstraße 8a, 80336 Munich, Germany.
| | - Katia Parodi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching b. München, Germany.
| |
Collapse
|
27
|
Aboulbanine Z, Khayati NE. A theoretical multileaf collimator model for fast Monte Carlo dose calculation of linac 6/10 MV photon beams. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/ab3510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
28
|
Shi M, Myronakis M, Hu YH, Jacobson M, Lehmann M, Fueglistaller R, Huber P, Baturin P, Wang A, Ferguson D, Harris T, Morf D, Berbeco R. A novel method for fast image simulation of flat panel detectors. ACTA ACUST UNITED AC 2019; 64:095019. [DOI: 10.1088/1361-6560/ab12aa] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
29
|
Teixeira M, Batista D, Braz D, da Rosa L. Monte Carlo simulation of Novalis Classic 6 MV accelerator using phase space generation in GATE/Geant4 code. PROGRESS IN NUCLEAR ENERGY 2019. [DOI: 10.1016/j.pnucene.2018.09.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
30
|
Shi M, Myronakis M, Hu YH, Morf D, Rottmann J, Berbeco R. A Monte Carlo study of the impact of phosphor optical properties on EPID imaging performance. Phys Med Biol 2018; 63:165013. [PMID: 30051879 DOI: 10.1088/1361-6560/aad647] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have developed a Monte Carlo computational model of a clinically employed electronic portal imaging device (EPID), and demonstrated the impact of phosphor optical properties on the imaging performance. The EPID model was built with Geant4 application for tomographic emission. Both radiative and optical transport were included in the model. Modulation transfer function (MTF), normalized noise-power spectrum times the incident x-ray fluence (qNNPS), and detective quantum efficiency (DQE) were calculated for simulated and measured data, and their agreement was quantified by the normalized root-mean-square error (NRMSE). MTF was computed using a 100 µm wide slit tilted by 1.5° and qNNPS was estimated using the Fujita-Lubberts-Swank method. DQE was calculated from MTF and qNNPS data. The NRMSE value was 0.0467 for MTF, 0.0217 for qNNPS, and 0.0885 for DQE, showing good agreement between measurement and simulation. Five major optical properties, phosphor grain size, phosphor thickness, phosphor refractive index, binder refractive index, and packing ratio were tested for their influence on the qNNPS, MTF, and DQE(0) of the model. Generally, the effect on the qNNPS is greater than MTF, and no impact on DQE(0), except from phosphor thickness, was observed. Multiple applications, such as imager design optimization and investigations of the dosimetric performance, are expected to benefit from the validated model.
Collapse
Affiliation(s)
- Mengying Shi
- Medical Physics Program, Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854, United States of America. Department of Radiation Oncology, Brigham and Women's Hospital, Dana Farber Cancer Institute and Harvard Medical School, Boston, MA 02115, United States of America
| | | | | | | | | | | |
Collapse
|
31
|
Ou H, Zhang B, Zhao S. Monte Carlo simulation of the relative biological effectiveness and DNA damage from a 400 MeV/u carbon ion beam in water. Appl Radiat Isot 2018; 136:1-9. [DOI: 10.1016/j.apradiso.2018.01.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 11/25/2022]
|
32
|
Myronakis M, Hu YH, Fueglistaller R, Wang A, Baturin P, Huber P, Morf D, Star-Lack J, Berbeco R. Multi-layer imager design for mega-voltage spectral imaging. Phys Med Biol 2018; 63:105002. [PMID: 29652670 DOI: 10.1088/1361-6560/aabe21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The architecture of multi-layer imagers (MLIs) can be exploited to provide megavoltage spectral imaging (MVSPI) for specific imaging tasks. In the current work, we investigated bone suppression and gold fiducial contrast enhancement as two clinical tasks which could be improved with spectral imaging. A method based on analytical calculations that enables rapid investigation of MLI component materials and thicknesses was developed and validated against Monte Carlo computations. The figure of merit for task-specific imaging performance was the contrast-to-noise ratio (CNR) of the gold fiducial when the CNR of bone was equal to zero after a weighted subtraction of the signals obtained from each MLI layer. Results demonstrated a sharp increase in the CNR of gold when the build-up component or scintillation materials and thicknesses were modified. The potential for low-cost, prompt implementation of specific modifications (e.g. composition of the build-up component) could accelerate clinical translation of MVSPI.
Collapse
Affiliation(s)
- Marios Myronakis
- Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, United States of America
| | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Aboulbanine Z, El Khayati N. Validation of a virtual source model of medical linac for Monte Carlo dose calculation using multi-threaded Geant4. ACTA ACUST UNITED AC 2018; 63:085008. [DOI: 10.1088/1361-6560/aab7a1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
34
|
Ahmed SR, Jia JM, Bruza P, Vinogradov S, Jiang S, Gladstone DJ, Jarvis LA, Pogue BW. Radiotherapy-induced Cherenkov luminescence imaging in a human body phantom. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-4. [PMID: 29560623 PMCID: PMC7560997 DOI: 10.1117/1.jbo.23.3.030504] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 02/26/2018] [Indexed: 05/25/2023]
Abstract
Radiation therapy produces Cherenkov optical emission in tissue, and this light can be utilized to activate molecular probes. The feasibility of sensing luminescence from a tissue molecular oxygen sensor from within a human body phantom was examined using the geometry of the axillary lymph node region. Detection of regions down to 30-mm deep was feasible with submillimeter spatial resolution with the total quantity of the phosphorescent sensor PtG4 near 1 nanomole. Radiation sheet scanning in an epi-illumination geometry provided optimal coverage, and maximum intensity projection images provided illustration of the concept. This work provides the preliminary information needed to attempt this type of imaging in vivo.
Collapse
Affiliation(s)
- Syed Rakin Ahmed
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Jeremy Mengyu Jia
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Petr Bruza
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Sergei Vinogradov
- University of Pennsylvania, Departments of Biophysics and Biochemistry and of Chemistry, Philadelphia, Pennsylvania, United States
| | - Shudong Jiang
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - David J. Gladstone
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
- Geisel School of Medicine at Dartmouth, Department of Medicine, Hanover, New Hampshire, United States
- Dartmouth–Hitchcock Medical Center, Norris Cotton Cancer Center, Lebanon, New Hampshire, United States
| | - Lesley A. Jarvis
- Geisel School of Medicine at Dartmouth, Department of Medicine, Hanover, New Hampshire, United States
- Dartmouth–Hitchcock Medical Center, Norris Cotton Cancer Center, Lebanon, New Hampshire, United States
| | - Brian W. Pogue
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
- Dartmouth–Hitchcock Medical Center, Norris Cotton Cancer Center, Lebanon, New Hampshire, United States
| |
Collapse
|
35
|
Arce P, Lagares JI. CPU time optimization and precise adjustment of the Geant4 physics parameters for a VARIAN 2100 C/D gamma radiotherapy linear accelerator simulation using GAMOS. Phys Med Biol 2018; 63:035007. [PMID: 29256451 DOI: 10.1088/1361-6560/aaa2b0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We have verified the GAMOS/Geant4 simulation model of a 6 MV VARIAN Clinac 2100 C/D linear accelerator by the procedure of adjusting the initial beam parameters to fit the percentage depth dose and cross-profile dose experimental data at different depths in a water phantom. Thanks to the use of a wide range of field sizes, from 2 × 2 cm2 to 40 × 40 cm2, a small phantom voxel size and high statistics, fine precision in the determination of the beam parameters has been achieved. This precision has allowed us to make a thorough study of the different physics models and parameters that Geant4 offers. The three Geant4 electromagnetic physics sets of models, i.e. Standard, Livermore and Penelope, have been compared to the experiment, testing the four different models of angular bremsstrahlung distributions as well as the three available multiple-scattering models, and optimizing the most relevant Geant4 electromagnetic physics parameters. Before the fitting, a comprehensive CPU time optimization has been done, using several of the Geant4 efficiency improvement techniques plus a few more developed in GAMOS.
Collapse
Affiliation(s)
- Pedro Arce
- Technology Department, Scientific Instrumentation Division, Medical Applications Unit, Centro de Investigaciones Energéticas, MedioAmbientales y Tecnológicas (CIEMAT), Madrid, Spain
| | | |
Collapse
|
36
|
Dowlatabadi H, Mowlavi AA, Ghorbani M. Monte Carlo Simulation of Siemens Primus plus Linac for 6 and 18 MV Photon Beams. J Biomed Phys Eng 2017; 7:333-346. [PMID: 29616199 PMCID: PMC5809928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 04/30/2017] [Indexed: 06/08/2023]
Abstract
OBJECTIVE The aim of the present study is to simulate 6 MV and 18 MV photon beam energies of a Siemens Primus Plus medical linear accelerator (Linac) and to verify the simulation by comparing the results with the measured data. METHODS The main components of the head of Siemens Primus Plus linac were simulated using MCNPX Monte Carlo (MC) code. To verify the results, experimental data of percentage depth dose (PDD) and beam dose profile for 5 × 5 cm2, 10 × 10 cm2 and 20 × 20 cm2 field sizes were measured and compared with simulation results. Moreover, gamma function was used to compare the measurement and simulation data. RESULTS The results show a good agreement, within 1%, was observed between the data calculated by the simulations and those obtained by measurement for 6 MV photon beam, while it was within 2% for 18 MV photon beam, except in the build-up region for both beams. Gamma index values were less than unity in most data points for all the mentioned energies and fields. To calculate the dose in the phantom, cells were selected in different modes, one of the modes due to the lack of dose gradient and overlapping, produced better results than others produce. CONCLUSION There was good settlement between measured and MC simulation values in this research. The simulation programs can be used for photon modes of Siemens Primus Plus linac in conditions in which it is not possible to perform experimental measurements.
Collapse
Affiliation(s)
- H Dowlatabadi
- Physics Department, School of Sciences, Payame Noor University of Mashhad, Mashhad, Iran
| | - A A Mowlavi
- Physics Department, School of Sciences, Hakim Sabzevari University, Sabzevar, Iran
- ICTP, Associate Federation Scheme, Medical Physics Field, Trieste, Italy
| | - M Ghorbani
- Biomedical Engineering and Medical Physics Department, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
37
|
Gholami S, Longo F, Nedaie HA, Berti A, Mousavi M, Meigooni AS. Application of Geant4 Monte Carlo simulation in dose calculations for small radiosurgical fields. Med Dosim 2017; 43:214-223. [PMID: 28988675 DOI: 10.1016/j.meddos.2017.08.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/21/2017] [Accepted: 08/25/2017] [Indexed: 11/17/2022]
Abstract
The Geant4 toolkit was used to develop a Monte Carlo (MC)-based engine for accurate dose calculations in small radiation field sizes. The Geant4 toolkit (version 10.1.p02) was used to simulate 6-MV photon beam of a Varian2100C linear accelerator that is being used for stereotactic radiosurgery (SRS) treatment with small radiation fields. Geometric models of 3 in-house designed radiosurgical divergent cones, with the diameters of their projections at the isocenter being 10, 20, and 30 mm, were simulated. The accuracy of the MC simulation technique was examined by reproducing several different simulated dosimetric parameters of the primary beams with the experimental data. The dose distributions are first checked for single beams for each cone, then standard multiple field (SMF) techniques are applied. A sample set of DICOM files from computed tomography (CT) scan imaging of a patient's head was converted to the Geant4 geometry format to implement MC-based engine for a clinical test. To validate the accuracy of the MC-based calculations for SMF arrangements, the isodose lines from MC simulation in water phantom were compared with the measured isodose lines using EBT3 Gafchromic film in Solid Water phantoms. Agreements between measured and simulated depth dose values and beam profiles for SRS cones were generally within 2%/2 mm. For output factors, the largest discrepancy was observed for 10 mm SRS cone, which was 1.7%. For SMF techniques, in SRS cones, the MC simulation and EBT3 Gafchromic film dosimetry were in acceptable agreement (5%/5 mm). Excellent agreement between the results of the MC-based and measured dose values for both single and SMF techniques in SRS cones indicates the ability of the Geant4 toolkit to be applied as the platform for treatment planning of advanced radiotherapy techniques.
Collapse
Affiliation(s)
- Somayeh Gholami
- Radiotherapy Oncology Research Centre, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran; The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, Trieste 34151, Italy.
| | - Francesco Longo
- Department of Physics, University of Trieste and INFN Trieste, Italy
| | - Hassan Ali Nedaie
- Radiotherapy Oncology Research Centre, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
| | - Alessio Berti
- Department of Physics, University of Trieste and INFN Trieste, Italy
| | - Mehdi Mousavi
- Faculty of Medicine, Jirof University of Medical Sciences, Jiroft, Iran
| | - Ali S Meigooni
- Comprehensive Cancer Centers of Nevada, Las Vegas, NV, United States
| |
Collapse
|
38
|
Nwankwo O, Glatting G, Wenz F, Fleckenstein J. A single-source photon source model of a linear accelerator for Monte Carlo dose calculation. PLoS One 2017; 12:e0183486. [PMID: 28886048 PMCID: PMC5590861 DOI: 10.1371/journal.pone.0183486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 08/05/2017] [Indexed: 11/18/2022] Open
Abstract
PURPOSE To introduce a new method of deriving a virtual source model (VSM) of a linear accelerator photon beam from a phase space file (PSF) for Monte Carlo (MC) dose calculation. MATERIALS AND METHODS A PSF of a 6 MV photon beam was generated by simulating the interactions of primary electrons with the relevant geometries of a Synergy linear accelerator (Elekta AB, Stockholm, Sweden) and recording the particles that reach a plane 16 cm downstream the electron source. Probability distribution functions (PDFs) for particle positions and energies were derived from the analysis of the PSF. These PDFs were implemented in the VSM using inverse transform sampling. To model particle directions, the phase space plane was divided into a regular square grid. Each element of the grid corresponds to an area of 1 mm2 in the phase space plane. The average direction cosines, Pearson correlation coefficient (PCC) between photon energies and their direction cosines, as well as the PCC between the direction cosines were calculated for each grid element. Weighted polynomial surfaces were then fitted to these 2D data. The weights are used to correct for heteroscedasticity across the phase space bins. The directions of the particles created by the VSM were calculated from these fitted functions. The VSM was validated against the PSF by comparing the doses calculated by the two methods for different square field sizes. The comparisons were performed with profile and gamma analyses. RESULTS The doses calculated with the PSF and VSM agree to within 3% /1 mm (>95% pixel pass rate) for the evaluated fields. CONCLUSION A new method of deriving a virtual photon source model of a linear accelerator from a PSF file for MC dose calculation was developed. Validation results show that the doses calculated with the VSM and the PSF agree to within 3% /1 mm.
Collapse
Affiliation(s)
- Obioma Nwankwo
- Department of Radiation Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Medical Radiation Physics/Radiation Protection, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- * E-mail:
| | - Gerhard Glatting
- Medical Radiation Physics/Radiation Protection, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany
| | - Frederik Wenz
- Department of Radiation Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Jens Fleckenstein
- Department of Radiation Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| |
Collapse
|
39
|
Benhalouche S, Bert J, Boussion N, Autret A, Pradier O, Visvikis D. GATE Monte-Carlo Simulation of an MV-CBCT Flat Panel for Synergistic Imaging and Dosimetric Applications in Radiotherapy. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2017. [DOI: 10.1109/trpms.2017.2718545] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
40
|
Wang B, van Roosmalen J, Piët L, van Schie MA, Beekman FJ, Goorden MC. Voxelized ray-tracing simulation dedicated to multi-pinhole molecular breast tomosynthesis. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa8012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
41
|
Myronakis M, Star-Lack J, Baturin P, Rottmann J, Morf D, Wang A, Hu YH, Shedlock D, Berbeco RI. A novel multilayer MV imager computational model for component optimization. Med Phys 2017; 44:4213-4222. [PMID: 28555935 DOI: 10.1002/mp.12382] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 04/18/2017] [Accepted: 05/21/2017] [Indexed: 12/28/2022] Open
Abstract
PURPOSE A novel Megavoltage (MV) multilayer imager (MLI) design featuring higher detective quantum efficiency and lower noise than current conventional MV imagers in clinical use has been recently reported. Optimization of the MLI design for multiple applications including tumor tracking, MV-CBCT and portal dosimetry requires a computational model that will provide insight into the physics processes that affect the overall and individual components' performance. The purpose of the current work was to develop and validate a comprehensive computational model that can be used for MLI optimization. METHODS The MLI model was built using the Geant4 Application for Tomographic Emission (GATE) application. The model includes x-ray and charged-particle interactions as well as the optical transfer within the phosphor. A first prototype MLI device featuring a stack of four detection layers was used for model validation. Each layer of the prototype contains a copper buildup plate, a phosphor screen and photodiode array. The model was validated against measured data of Modulation Transfer Function (MTF), Noise-Power Spectrum (NPS), and Detective Quantum Efficiency (DQE). MTF was computed using a slanted slit with 2.3° angle and 0.1 mm width. NPS was obtained using the autocorrelation function technique. DQE was calculated from MTF and NPS data. The comparison metrics between simulated and measured data were the Pearson's correlation coefficient (r) and the normalized root-mean-square error (NRMSE). RESULTS Good agreement between measured and simulated MTF and NPS values was observed. Pearson's correlation coefficient for the combined signal from all layers of the MLI was equal to 0.9991 for MTF and 0.9992 for NPS; NRMSE was 0.0121 for MTF and 0.0194 for NPS. Similarly, the DQE correlation coefficient for the combined signal was 0.9888 and the NRMSE was 0.0686. CONCLUSIONS A comprehensive model of the novel MLI design was developed using the GATE toolkit and validated against measured MTF, NPS, and DQE data acquired with a prototype device featuring four layers. This model will be used for further optimization of the imager components and configuration for clinical radiotherapy applications.
Collapse
Affiliation(s)
- Marios Myronakis
- Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center and Harvard Medical School, Boston, MA, 02115, USA
| | - Josh Star-Lack
- Varian Medical Systems Ginzton Technology Center, Palo Alto, CA, 94304-1030, USA
| | - Paul Baturin
- Varian Medical Systems Ginzton Technology Center, Palo Alto, CA, 94304-1030, USA
| | - Joerg Rottmann
- Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center and Harvard Medical School, Boston, MA, 02115, USA
| | - Daniel Morf
- Varian Medical Systems, Baden-Dattwil, CH- 5405, Switzerland
| | - Adam Wang
- Varian Medical Systems Ginzton Technology Center, Palo Alto, CA, 94304-1030, USA
| | - Yue-Houng Hu
- Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center and Harvard Medical School, Boston, MA, 02115, USA
| | | | - Ross I Berbeco
- Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center and Harvard Medical School, Boston, MA, 02115, USA
| |
Collapse
|
42
|
Costa GCA, Sa LVD, Bonifacio DAB. Application of GATE/Geant4 for internal dosimetry using male ICRP reference voxel phantom by specific absorbed fractions calculations for photon irradiation. Biomed Phys Eng Express 2015. [DOI: 10.1088/2057-1976/1/4/045201] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
43
|
Didi S, Moussa A, Yahya T, Mustafa Z. Simulation of the 6 MV Elekta Synergy Platform linac photon beam using Geant4 Application for Tomographic Emission. J Med Phys 2015; 40:136-43. [PMID: 26500399 PMCID: PMC4594382 DOI: 10.4103/0971-6203.165077] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The present work validates the Geant4 Application for Tomographic Emission Monte Carlo software for the simulation of a 6 MV photon beam given by Elekta Synergy Platform medical linear accelerator treatment head. The simulation includes the major components of the linear accelerator (LINAC) with multi-leaf collimator and a homogeneous water phantom. Calculations were performed for the photon beam with several treatment field sizes ranging from 5 cm × 5 cm to 30 cm × 30 cm at 100 cm distance from the source. The simulation was successfully validated by comparison with experimental distributions. Good agreement between simulations and measurements was observed, with dose differences of about 0.02% and 2.5% for depth doses and lateral dose profiles, respectively. This agreement was also emphasized by the Kolmogorov-Smirnov goodness-of-fit test and by the gamma-index comparisons where more than 99% of the points for all simulations fulfill the quality assurance criteria of 2 mm/2%.
Collapse
Affiliation(s)
- Samir Didi
- Department of Physics, Laboratory of Physics of Radiation and Matter, Faculty of Sciences, University Mohammed First, Oujda 60000, Morocco ; Department of Physics, Regional Hassan II Oncology Center, Oujda 60000, Morocco
| | - Abdelilah Moussa
- Department of Physics, Laboratory of Physics of Radiation and Matter, Faculty of Sciences, University Mohammed First, Oujda 60000, Morocco ; Department of Physics, National School of Applied sciences of Al-Hoceima, Morocco
| | - Tayalati Yahya
- Department of Physics, Laboratory of Physics of Radiation and Matter, Faculty of Sciences, University Mohammed First, Oujda 60000, Morocco
| | - Zerfaoui Mustafa
- Department of Physics, Laboratory of Physics of Radiation and Matter, Faculty of Sciences, University Mohammed First, Oujda 60000, Morocco ; Department of Physics, Regional Hassan II Oncology Center, Oujda 60000, Morocco
| |
Collapse
|
44
|
Sarrut D, Bardiès M, Boussion N, Freud N, Jan S, Létang JM, Loudos G, Maigne L, Marcatili S, Mauxion T, Papadimitroulas P, Perrot Y, Pietrzyk U, Robert C, Schaart DR, Visvikis D, Buvat I. A review of the use and potential of the GATE Monte Carlo simulation code for radiation therapy and dosimetry applications. Med Phys 2015; 41:064301. [PMID: 24877844 DOI: 10.1118/1.4871617] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In this paper, the authors' review the applicability of the open-source GATE Monte Carlo simulation platform based on the GEANT4 toolkit for radiation therapy and dosimetry applications. The many applications of GATE for state-of-the-art radiotherapy simulations are described including external beam radiotherapy, brachytherapy, intraoperative radiotherapy, hadrontherapy, molecular radiotherapy, and in vivo dose monitoring. Investigations that have been performed using GEANT4 only are also mentioned to illustrate the potential of GATE. The very practical feature of GATE making it easy to model both a treatment and an imaging acquisition within the same framework is emphasized. The computational times associated with several applications are provided to illustrate the practical feasibility of the simulations using current computing facilities.
Collapse
Affiliation(s)
- David Sarrut
- Université de Lyon, CREATIS; CNRS UMR5220; Inserm U1044; INSA-Lyon; Université Lyon 1; Centre Léon Bérard, France
| | - Manuel Bardiès
- Inserm, UMR1037 CRCT, F-31000 Toulouse, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, F-31000 Toulouse, France
| | | | - Nicolas Freud
- Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Centre Léon Bérard, 69008 Lyon, France
| | | | - Jean-Michel Létang
- Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Centre Léon Bérard, 69008 Lyon, France
| | - George Loudos
- Department of Medical Instruments Technology, Technological Educational Institute of Athens, Athens 12210, Greece
| | - Lydia Maigne
- UMR 6533 CNRS/IN2P3, Université Blaise Pascal, 63171 Aubière, France
| | - Sara Marcatili
- Inserm, UMR1037 CRCT, F-31000 Toulouse, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, F-31000 Toulouse, France
| | - Thibault Mauxion
- Inserm, UMR1037 CRCT, F-31000 Toulouse, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, F-31000 Toulouse, France
| | - Panagiotis Papadimitroulas
- Department of Biomedical Engineering, Technological Educational Institute of Athens, 12210, Athens, Greece
| | - Yann Perrot
- UMR 6533 CNRS/IN2P3, Université Blaise Pascal, 63171 Aubière, France
| | - Uwe Pietrzyk
- Institut für Neurowissenschaften und Medizin, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany and Fachbereich für Mathematik und Naturwissenschaften, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
| | - Charlotte Robert
- IMNC, UMR 8165 CNRS, Universités Paris 7 et Paris 11, Orsay 91406, France
| | - Dennis R Schaart
- Delft University of Technology, Faculty of Applied Sciences, Radiation Science and Technology Department, Delft Mekelweg 15, 2629 JB Delft, The Netherlands
| | | | - Irène Buvat
- IMNC, UMR 8165 CNRS, Universités Paris 7 et Paris 11, 91406 Orsay, France and CEA/DSV/I2BM/SHFJ, 91400 Orsay, France
| |
Collapse
|
45
|
Smekens F, Létang JM, Noblet C, Chiavassa S, Delpon G, Freud N, Rit S, Sarrut D. Split exponential track length estimator for Monte-Carlo simulations of small-animal radiation therapy. Phys Med Biol 2014; 59:7703-15. [DOI: 10.1088/0031-9155/59/24/7703] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
46
|
Reis Junior J, Salmon H, Menezes A, Pavan G, Rosa L, Silva A. Simulation of Siemens ONCOR™ Expression linear accelerator using phase space in the MCNPX code. PROGRESS IN NUCLEAR ENERGY 2014. [DOI: 10.1016/j.pnucene.2013.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
47
|
Simulation of realistic linac motion improves the accuracy of a Monte Carlo based VMAT plan QA system. Radiother Oncol 2013; 109:377-83. [DOI: 10.1016/j.radonc.2013.08.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 08/14/2013] [Accepted: 08/31/2013] [Indexed: 11/21/2022]
|
48
|
Ramos-Méndez J, Perl J, Faddegon B, Schümann J, Paganetti H. Geometrical splitting technique to improve the computational efficiency in Monte Carlo calculations for proton therapy. Med Phys 2013; 40:041718. [PMID: 23556888 DOI: 10.1118/1.4795343] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To present the implementation and validation of a geometrical based variance reduction technique for the calculation of phase space data for proton therapy dose calculation. METHODS The treatment heads at the Francis H Burr Proton Therapy Center were modeled with a new Monte Carlo tool (TOPAS based on Geant4). For variance reduction purposes, two particle-splitting planes were implemented. First, the particles were split upstream of the second scatterer or at the second ionization chamber. Then, particles reaching another plane immediately upstream of the field specific aperture were split again. In each case, particles were split by a factor of 8. At the second ionization chamber and at the latter plane, the cylindrical symmetry of the proton beam was exploited to position the split particles at randomly spaced locations rotated around the beam axis. Phase space data in IAEA format were recorded at the treatment head exit and the computational efficiency was calculated. Depth-dose curves and beam profiles were analyzed. Dose distributions were compared for a voxelized water phantom for different treatment fields for both the reference and optimized simulations. In addition, dose in two patients was simulated with and without particle splitting to compare the efficiency and accuracy of the technique. RESULTS A normalized computational efficiency gain of a factor of 10-20.3 was reached for phase space calculations for the different treatment head options simulated. Depth-dose curves and beam profiles were in reasonable agreement with the simulation done without splitting: within 1% for depth-dose with an average difference of (0.2 ± 0.4)%, 1 standard deviation, and a 0.3% statistical uncertainty of the simulations in the high dose region; 1.6% for planar fluence with an average difference of (0.4 ± 0.5)% and a statistical uncertainty of 0.3% in the high fluence region. The percentage differences between dose distributions in water for simulations done with and without particle splitting were within the accepted clinical tolerance of 2%, with a 0.4% statistical uncertainty. For the two patient geometries considered, head and prostate, the efficiency gain was 20.9 and 14.7, respectively, with the percentages of voxels with gamma indices lower than unity 98.9% and 99.7%, respectively, using 2% and 2 mm criteria. CONCLUSIONS The authors have implemented an efficient variance reduction technique with significant speed improvements for proton Monte Carlo simulations. The method can be transferred to other codes and other treatment heads.
Collapse
Affiliation(s)
- José Ramos-Méndez
- Benemérita Universidad Autónoma de Puebla, 18 Sur and San Claudio Avenue, Puebla, Puebla 72750, Mexico.
| | | | | | | | | |
Collapse
|
49
|
Bahreyni Toossi MT, Behmadi M, Ghorbani M, Gholamhosseinian H. A Monte Carlo study on electron and neutron contamination caused by the presence of hip prosthesis in photon mode of a 15 MV Siemens PRIMUS linac. J Appl Clin Med Phys 2013; 14:52-67. [PMID: 24036859 PMCID: PMC5714559 DOI: 10.1120/jacmp.v14i5.4253] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 06/01/2013] [Accepted: 05/27/2013] [Indexed: 12/05/2022] Open
Abstract
Several investigators have pointed out that electron and neutron contamination from high‐energy photon beams are clinically important. The aim of this study is to assess electron and neutron contamination production by various prostheses in a high‐energy photon beam of a medical linac. A 15 MV Siemens PRIMUS linac was simulated by MCNPX Monte Carlo (MC) code and the results of percentage depth dose (PDD) and dose profile values were compared with the measured data. Electron and neutron contaminations were calculated on the beam's central axis for Co‐Cr‐Mo, stainless steel, Ti‐alloy, and Ti hip prostheses through MC simulations. Dose increase factor (DIF) was calculated as the ratio of electron (neutron) dose at a point for 10×10 cm2 field size in presence of prosthesis to that at the same point in absence of prosthesis. DIF was estimated at different depths in a water phantom. Our MC‐calculated PDD and dose profile data are in good agreement with the corresponding measured values. Maximum dose increase factor for electron contamination for Co‐Cr‐Mo, stainless steel, Ti‐alloy, and Ti prostheses were equal to 1.18, 1.16, 1.16, and 1.14, respectively. The corresponding values for neutron contamination were respectively equal to: 184.55, 137.33, 40.66, and 43.17. Titanium‐based prostheses are recommended for the orthopedic practice of hip junction replacement. When treatment planning for a patient with hip prosthesis is performed for a high‐energy photon beam, attempt should be made to ensure that the prosthesis is not exposed to primary photons. PACS numbers: 87.56.bd, 87.55.kh, 87.55.Gh
Collapse
|
50
|
Benhalouche S, Visvikis D, Le Maitre A, Pradier O, Boussion N. Evaluation of clinical IMRT treatment planning using the GATE Monte Carlo simulation platform for absolute and relative dose calculations. Med Phys 2013; 40:021711. [DOI: 10.1118/1.4774358] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
|