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Huang Z, Tian L, Janssens G, Smeets J, Xie Y, Kevin Teo BK, Nilsson R, Traneus E, Parodi K, Pinto M. An experimental validation of a filtering approach for prompt gamma prediction in a research proton treatment planning system. Phys Med Biol 2024; 69:155025. [PMID: 38981589 DOI: 10.1088/1361-6560/ad6116] [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: 01/24/2024] [Accepted: 07/09/2024] [Indexed: 07/11/2024]
Abstract
Objective.Prompt gamma (PG) radiation generated from nuclear reactions between protons and tissue nuclei can be employed for range verification in proton therapy. A typical clinical workflow for PG range verification compares the detected PG profile with a predicted one. Recently, a novel analytical PG prediction algorithm based on the so-called filtering formalism has been proposed and implemented in a research version of RayStation (RaySearch Laboratories AB), which is a widely adopted treatment planning system. This work validates the performance of the filtering PG prediction approach.Approach.The said algorithm is validated against experimental data and benchmarked with another well-established PG prediction algorithm implemented in a MATLAB-based software REGGUI. Furthermore, a new workflow based on several PG profile quality criteria and analytical methods is proposed for data selection. The workflow also calculates sensitivity and specificity information, which can help practitioners to decide on irradiation course interruption during treatment and monitor spot selection at the treatment planning stage. With the proposed workflow, the comparison can be performed on a limited number of selected high-quality irradiation spots without neighbouring-spot aggregation.Main results.The mean shifts between the experimental data and the predicted PG detection (PGD) profiles (ΔPGD) by the two algorithms are estimated to be1.5±2.1mm and-0.6±2.2mm for the filtering and REGGUI prediction methods, respectively. The ΔPGD difference between two algorithms is observed to be consistent with the beam model difference within uncertainty. However, the filtering approach requires a much shorter computation time compared to the REGGUI approach.Significance.The novel filtering approach is successfully validated against experimental data and another widely used PG prediction algorithm. The workflow designed in this work selects spots with high-quality PGD shift calculation results, and performs sensitivity and specificity analyses to assist clinical decisions.
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Affiliation(s)
- Ze Huang
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Liheng Tian
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | | | - Yunhe Xie
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Boon-Keng Kevin Teo
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States of America
| | | | | | - Katia Parodi
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marco Pinto
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
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Hetzel R, Urbanevych V, Bolke A, Kasper J, Kercz M, Kołodziej M, Magiera A, Mueller F, Müller S, Rafecas M, Rusiecka K, Schug D, Schulz V, Stahl A, Weissler B, Wong ML, Wrońska A. Near-field coded-mask technique and its potential for proton therapy monitoring. Phys Med Biol 2023; 68:245028. [PMID: 37863101 DOI: 10.1088/1361-6560/ad05b2] [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: 02/10/2023] [Accepted: 10/20/2023] [Indexed: 10/22/2023]
Abstract
Objective.Prompt-gamma imaging encompasses several approaches to the online monitoring of the beam range or deposited dose distribution in proton therapy. We test one of the imaging techniques - a coded mask approach - both experimentally and via simulations.Approach.Two imaging setups have been investigated experimentally. Each of them comprised a structured tungsten collimator in the form of a modified uniformly redundant array mask and a LYSO:Ce scintillation detector of fine granularity. The setups differed in detector dimensions and operation mode (1D or 2D imaging). A series of measurements with radioactive sources have been conducted, testing the performance of the setups for near-field gamma imaging. Additionally, Monte Carlo simulations of a larger setup of the same type were conducted, investigating its performance with a realistic gamma source distribution occurring during proton therapy.Main results.The images of point-like sources reconstructed from two small-scale prototypes' data using the maximum-likelihood expectation maximisation algorithm constitute the experimental proof of principle for the near-field coded-mask imaging modality, both in the 1D and the 2D mode. Their precision allowed us to calibrate out certain systematic offsets appearing due to the limited alignment accuracy of setup elements. The simulation of the full-scale setup yielded a mean distal falloff retrieval precision of 0.72 mm in the studies for beam energy range 89.5-107.9 MeV and with 1 × 108protons (a typical number for distal spots). The implemented algorithm of image reconstruction is relatively fast-a typical procedure needs several seconds.Significance.Coded-mask imaging appears a valid option for proton therapy monitoring. The results of simulations let us conclude that the proposed full-scale setup is competitive with the knife-edge-shaped and the multi-parallel slit cameras investigated by other groups.
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Affiliation(s)
- Ronja Hetzel
- III. Physikalisches Institut B, RWTH Aachen University, Aachen, Germany
| | - Vitalii Urbanevych
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - Andreas Bolke
- Institute of Medical Engineering, University of Lübeck, Lübeck, Germany
| | - Jonas Kasper
- III. Physikalisches Institut B, RWTH Aachen University, Aachen, Germany
| | - Monika Kercz
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
- Doctoral School of Exact and Natural Sciences, Jagiellonian University, Kraków, Poland
| | - Magdalena Kołodziej
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
- Doctoral School of Exact and Natural Sciences, Jagiellonian University, Kraków, Poland
| | - Andrzej Magiera
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - Florian Mueller
- Physics of Molecular Imaging Systems, RWTH Aachen University, Aachen, Germany
| | - Sara Müller
- III. Physikalisches Institut B, RWTH Aachen University, Aachen, Germany
| | - Magdalena Rafecas
- Institute of Medical Engineering, University of Lübeck, Lübeck, Germany
| | - Katarzyna Rusiecka
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - David Schug
- Physics of Molecular Imaging Systems, RWTH Aachen University, Aachen, Germany
- Hyperion Hybrid Imaging Systems GmbH, Aachen, Germany
| | - Volkmar Schulz
- III. Physikalisches Institut B, RWTH Aachen University, Aachen, Germany
- Physics of Molecular Imaging Systems, RWTH Aachen University, Aachen, Germany
- Hyperion Hybrid Imaging Systems GmbH, Aachen, Germany
| | - Achim Stahl
- III. Physikalisches Institut B, RWTH Aachen University, Aachen, Germany
| | - Bjoern Weissler
- Physics of Molecular Imaging Systems, RWTH Aachen University, Aachen, Germany
- Hyperion Hybrid Imaging Systems GmbH, Aachen, Germany
| | - Ming-Liang Wong
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - Aleksandra Wrońska
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
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Ekinci F, Asuroglu T, Acici K. Monte Carlo Simulation of TRIM Algorithm in Ceramic Biomaterial in Proton Therapy. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4833. [PMID: 37445147 DOI: 10.3390/ma16134833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023]
Abstract
Biomaterials play a crucial role in enhancing human health and quality of life. They are employed in applications such as tissue substitution, diagnostic tools, medical supplies, therapeutic treatments, regenerative medicine, and radiation dosimetric studies. However, their predisposition to proton therapy, which is a trending treatment in the world, has not been adequately studied. Ceramic biomaterials, known for their hardness and durability, offer versatile uses, especially in bone tissue replacements. The wide range of physical, mechanical, and chemical properties exhibited by ceramics has spurred extensive research, development, and application in this field. This study focuses on investigating and analyzing the ionization, recoils, phonon release, collision events, and lateral scattering properties of ceramic biomaterials that closely resemble bone tissue in proton therapy applications. Monte Carlo (MC) Transport of Ions in Matter (TRIM) simulation tools were utilized for this analysis. The results showed that Silicon dioxide exhibited the Bragg peak position closest to bone tissue, with a deviation of 10.6%. The average recoils differed by 1.7%, and the lateral scattering differed by 3.6%. The main innovation of this study lies in considering interactions such as recoil, collision events, phonon production, and lateral scattering when selecting biomaterials, despite their limited digitization and understanding. By evaluating all these interactions, the study aimed to identify the most suitable ceramic biomaterial to replace bone tissue in proton therapy.
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Affiliation(s)
- Fatih Ekinci
- Institute of Nuclear Sciences, Ankara University, 06830 Ankara, Turkey
| | - Tunc Asuroglu
- Faculty of Medicine and Health Technology, Tampere University, 33720 Tampere, Finland
| | - Koray Acici
- Artifical Intelligence and Data Engineerig, Ankara University, 06830 Ankara, Turkey
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Mohammadi A, Tashima H, Takyu S, Iwao Y, Akamatsu G, Kang HG, Obata F, Nishikido F, Parodi K, Yamaya T. Feasibility of triple gamma ray imaging of 10C for range verification in ion therapy. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac826a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 07/19/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. In carbon ion therapy, the visualization of the range of incident particles in a patient body is important for treatment verification. In-beam positron emission tomography (PET) imaging is one of the methods to verify the treatment in ion therapy due to the high quality of PET images. We have shown the feasibility of in-beam PET imaging of radioactive 15O and 11C ion beams for range verification using our OpenPET system. Recently, we developed a whole gamma imager (WGI) that can simultaneously work as PET, single gamma ray and triple gamma ray imaging. The WGI has high potential to detect the location of 10C, which emits positrons with a simultaneous gamma ray of 718 keV, within the patient’s body during ion therapy. Approach. In this work, we focus on investigating the performance of WGI for 10C imaging and its feasibility for range verification in carbon ion therapy. First, the performance of the WGI was studied to image a 10C point source using the Geant4 toolkit. Then, the feasibility of WGI was investigated for an irradiated polymethyl methacrylate (PMMA) phantom with a 10C ion beam at the carbon therapy facility of the Heavy Ion Medical Accelerator in Chiba. Main results. The average spatial resolution and sensitivity for the simulated 10C point source at the centre of the field of view were 5.5 mm FWHM and 0.010%, respectively. The depth dose of the 10C ion beam was measured, and the triple gamma image of 10C nuclides for an irradiated PMMA phantom was obtained by applying a simple back projection to the detected triple gammas. Significance. The shift between Bragg peak position and position of the peak of the triple gamma image in an irradiated PMMA phantom was 2.8 ± 0.8 mm, which demonstrates the capability of triple gamma imaging using WGI for range verification of 10C ion beams.
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Kazemi Kozani M, Magiera A. Machine learning-based event recognition in SiFi Compton camera imaging for proton therapy monitoring. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac71f2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 05/20/2022] [Indexed: 11/11/2022]
Abstract
Abstract
Objective. Online monitoring of dose distribution in proton therapy is currently being investigated with the detection of prompt gamma (PG) radiation emitted from a patient during irradiation. The SiPM and scintillation Fiber based Compton Camera (SiFi-CC) setup is being developed for this aim. Approach. A machine learning approach to recognize Compton events is proposed, reconstructing the PG emission profile during proton therapy. The proposed method was verified on pseudo-data generated by a Geant4 simulation for a single proton beam impinging on a polymethyl methacrylate (PMMA) phantom. Three different models including the boosted decision tree (BDT), multilayer perception (MLP) neural network, and k-nearest neighbour (k-NN) were trained using 10-fold cross-validation and then their performances were assessed using the receiver operating characteristic (ROI) curves. Subsequently, after event selection by the most robust model, a software based on the List-Mode Maximum Likelihood Estimation Maximization (LM-MLEM) algorithm was applied for the reconstruction of the PG emission distribution profile. Main results. It was demonstrated that the BDT model excels in signal/background separation compared to the other two. Furthermore, the reconstructed PG vertex distribution after event selection showed a significant improvement in distal falloff position determination. Significance. A highly satisfactory agreement between the reconstructed distal edge position and that of the simulated Compton events was achieved. It was also shown that a position resolution of 3.5 mm full width at half maximum (FWHM) in distal edge position determination is feasible with the proposed setup.
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Chalise AR, Chi Y, Lai Y, Shao Y, Jin M. Carbon-11 and Carbon-12 beam range verifications through prompt gamma and annihilation gamma measurements: Monte Carlo simulations. Biomed Phys Eng Express 2020; 6:065013. [PMID: 34040798 PMCID: PMC8148632 DOI: 10.1088/2057-1976/abb8b6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Range uncertainty remains a big concern in particle therapy, as it may cause target dose degradation and normal tissue overdosing. Positron emission tomography (PET) and prompt gamma imaging (PGI) are two promising modalities for range verification. However, the relatively long acquisition time of PET and the relatively low yield of PGI pose challenges for real-time range verification. In this paper, we explore using the primary Carbon-11 (C-11) ion beams to enhance the gamma yield compared to the primary C-12 ion beams to improve PET and PGI by using Monte Carlo simulations of water and PMMA phantoms at four incident energies (95, 200, 300, and 430 MeV u-1). Prompt gammas (PGs) and annihilation gammas (AGs) were recorded for post-processing to mimic PGI and PET imaging, respectively. We used both time-of-flight (TOF) and energy selections for PGI, which boosted the ratio of PGs to background neutrons to 2.44, up from 0.87 without the selections. At the lowest incident energy (100 MeVu-1), PG yield from C-11 was 0.82 times of that from C-12, while AG yield from C-11 was 6 ∼ 11 folds higher than from C-12 in PMMA. At higher energies, PG differences between C-11 and C-12 were much smaller, while AG yield from C-11 was 30%∼90% higher than from C-12 using minute-acquisition. With minute-acquisition, the AG depth distribution of C-11 showed a sharp peak coincident with the Bragg peak due to the decay of the primary C-11 ions, but that of C-12 had no such one. The high AG yield and distinct peaks could lead to more precise range verification of C-11 than C-12. These results demonstrate that using C-11 ion beams for potentially combined PGI and PET has great potential to improve online single-spot range verification accuracy and precision.
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Affiliation(s)
- Ananta Raj Chalise
- Department of Physics, University of Texas at Arlington, Arlington, TX 76019, United States of America
| | - Yujie Chi
- Department of Physics, University of Texas at Arlington, Arlington, TX 76019, United States of America
| | - Youfang Lai
- Department of Physics, University of Texas at Arlington, Arlington, TX 76019, United States of America
| | - Yiping Shao
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390, United States of America
| | - Mingwu Jin
- Department of Physics, University of Texas at Arlington, Arlington, TX 76019, United States of America
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Durante M, Parodi K. Radioactive Beams in Particle Therapy: Past, Present, and Future. FRONTIERS IN PHYSICS 2020; 8:00326. [PMID: 33224941 PMCID: PMC7116396 DOI: 10.3389/fphy.2020.00326] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Heavy ion therapy can deliver high doses with high precision. However, image guidance is needed to reduce range uncertainty. Radioactive ions are potentially ideal projectiles for radiotherapy because their decay can be used to visualize the beam. Positron-emitting ions that can be visualized with PET imaging were already studied for therapy application during the pilot therapy project at the Lawrence Berkeley Laboratory, and later within the EULIMA EU project, the GSI therapy trial in Germany, MEDICIS at CERN, and at HIMAC in Japan. The results show that radioactive ion beams provide a large improvement in image quality and signal-to-noise ratio compared to stable ions. The main hindrance toward a clinical use of radioactive ions is their challenging production and the low intensities of the beams. New research projects are ongoing in Europe and Japan to assess the advantages of radioactive ion beams for therapy, to develop new detectors, and to build sources of radioactive ions for medical synchrotrons.
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Affiliation(s)
- Marco Durante
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Darmstadt, Germany
- Correspondence: Marco Durante,
| | - Katia Parodi
- Department of Experimental Physics—Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
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8
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The SiFi-CC project – Feasibility study of a scintillation-fiber-based Compton camera for proton therapy monitoring. Phys Med 2020; 76:317-325. [DOI: 10.1016/j.ejmp.2020.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/19/2020] [Accepted: 07/09/2020] [Indexed: 11/15/2022] Open
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Dal Bello R, Magalhaes Martins P, Brons S, Hermann G, Kihm T, Seimetz M, Seco J. Prompt gamma spectroscopy for absolute range verification of 12C ions at synchrotron-based facilities. Phys Med Biol 2020; 65:095010. [PMID: 32092707 DOI: 10.1088/1361-6560/ab7973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The physical range uncertainty limits the exploitation of the full potential of charged particle therapy. In this work, we face this issue aiming to measure the absolute Bragg peak position in the target. We investigate p, 4He, 12C and 16O beams accelerated at the Heidelberg Ion-Beam Therapy Center. The residual range of the primary 12C ions is correlated to the energy spectrum of the prompt gamma radiation. The prompt gamma spectroscopy method was demonstrated for proton beams accelerated by cyclotrons and is developed here for the first time for heavier ions accelerated by a synchrotron. We develop a detector system that includes (i) a spectroscopic unit based on cerium(III) bromide and bismuth germanium oxide scintillating crystals, (ii) a beam trigger based on an array of scintillating fibers and (iii) a data acquisition system based on a FlashADC. We test the system in two different scenarios. In the first series of experiments, we detect and identify 19 independent spectral lines over a wide gamma energy spectrum in the presence of the four ion species for different targets, including a water target with a titanium insert. In the second series of experiments, we introduce a collimator aiming to relate the spectral information to the range of the primary particles. We perform extensive measurements for a 12C beam and demonstrate submillimetric precision for the measurement of its Bragg peak position in the experimental setup. The features of the energy and time spectra for gamma radiation induced by p, 4He and 16O are investigated upstream and downstream from the Bragg peak position. We conclude the analysis by extrapolating the required future developments, which would be needed to achieve range verification with a 2 mm accuracy during a single fraction delivery of [Formula: see text] physical dose.
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Affiliation(s)
- Riccardo Dal Bello
- Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany. Department of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
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Hueso-González F, Bortfeld T. Compact Method for Proton Range Verification Based on Coaxial Prompt Gamma-Ray Monitoring: a Theoretical Study. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2020; 4:170-183. [PMID: 32258856 PMCID: PMC7111431 DOI: 10.1109/trpms.2019.2930362] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Range uncertainties in proton therapy hamper treatment precision. Prompt gamma-rays were suggested 16 years ago for real-time range verification, and have already shown promising results in clinical studies with collimated cameras. Simultaneously, alternative imaging concepts without collimation are investigated to reduce the footprint and price of current prototypes. In this manuscript, a compact range verification method is presented. It monitors prompt gamma-rays with a single scintillation detector positioned coaxially to the beam and behind the patient. Thanks to the solid angle effect, proton range deviations can be derived from changes in the number of gamma-rays detected per proton, provided that the number of incident protons is well known. A theoretical background is formulated and the requirements for a future proof-of-principle experiment are identified. The potential benefits and disadvantages of the method are discussed, and the prospects and potential obstacles for its use during patient treatments are assessed. The final milestone is to monitor proton range differences in clinical cases with a statistical precision of 1 mm, a material cost of 25000 USD and a weight below 10 kg. This technique could facilitate the widespread application of in vivo range verification in proton therapy and eventually the improvement of treatment quality.
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Affiliation(s)
- F Hueso-González
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - T Bortfeld
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
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Zarifi M, Guatelli S, Qi Y, Bolst D, Prokopovich D, Rosenfeld A. Characterization of prompt gamma ray emission for in vivo range verification in particle therapy: A simulation study. Phys Med 2019; 62:20-32. [DOI: 10.1016/j.ejmp.2019.04.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 04/15/2019] [Accepted: 04/24/2019] [Indexed: 11/27/2022] Open
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12
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Application of variance‐based uncertainty and sensitivity analysis to biological modeling in carbon ion treatment plans. Med Phys 2018; 46:437-447. [DOI: 10.1002/mp.13306] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/14/2018] [Accepted: 11/09/2018] [Indexed: 01/24/2023] Open
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Hueso-González F, Rabe M, Ruggieri TA, Bortfeld T, Verburg JM. A full-scale clinical prototype for proton range verification using prompt gamma-ray spectroscopy. Phys Med Biol 2018; 63:185019. [PMID: 30033938 PMCID: PMC6340397 DOI: 10.1088/1361-6560/aad513] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We present a full-scale clinical prototype system for in vivo range verification of proton pencil-beams using the prompt gamma-ray spectroscopy method. The detection system consists of eight LaBr3 scintillators and a tungsten collimator, mounted on a rotating frame. Custom electronics and calibration algorithms have been developed for the measurement of energy- and time-resolved gamma-ray spectra during proton irradiation at a clinical dose rate. Using experimentally determined nuclear reaction cross sections and a GPU-accelerated Monte Carlo simulation, a detailed model of the expected gamma-ray emissions is created for each individual pencil-beam. The absolute range of the proton pencil-beams is determined by minimizing the discrepancy between the measurement and this model, leaving the absolute range of the beam and the elemental concentrations of the irradiated matter as free parameters. The system was characterized in a clinical-like situation by irradiating different phantoms with a scanning pencil-beam. A dose of 0.9 Gy was delivered to a [Formula: see text] cm3 target with a beam current of 2 nA incident on the phantom. Different range shifters and materials were used to test the robustness of the verification method and to calculate the accuracy of the detected range. The absolute proton range was determined for each spot of the distal energy layer with a mean statistical precision of 1.1 mm at a 95% confidence level and a mean systematic deviation of 0.5 mm, when aggregating pencil-beam spots within a cylindrical region of 10 mm radius and 10 mm depth. Small range errors that we introduced were successfully detected and even large differences in the elemental composition do not affect the range verification accuracy. These results show that our system is suitable for range verification during patient treatments in our upcoming clinical study.
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Affiliation(s)
- Fernando Hueso-González
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
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Lin HH, Chang HT, Chao TC, Chuang KS. A comparison of two prompt gamma imaging techniques with collimator-based cameras for range verification in proton therapy. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2016.04.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Vanstalle M, Mattei I, Sarti A, Bellini F, Bini F, Collamati F, Lucia ED, Durante M, Faccini R, Ferroni F, Finck C, Fiore S, Marafini M, Patera V, Piersanti L, Rovituso M, Schuy C, Sciubba A, Traini G, Voena C, Tessa CL. Benchmarking Geant4 hadronic models for prompt‐
γ
monitoring in carbon ion therapy. Med Phys 2017; 44:4276-4286. [DOI: 10.1002/mp.12348] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 04/20/2017] [Accepted: 04/26/2017] [Indexed: 11/06/2022] Open
Affiliation(s)
| | | | - Alessio Sarti
- Laboratori Nazionali di Frascati dell'INFN Frascati Italy
| | | | - Fabiano Bini
- Dipartimento di Ingegneria Meccanica e Aerospaziale Sapienza Universita di Roma Roma Italy
| | | | - Erika De Lucia
- Laboratori Nazionali di Frascati dell'INFN Frascati Italy
| | - Marco Durante
- GSI Helmholtzzentrum für Schwerionenforschung Darmstadt Germany
| | | | | | | | | | | | | | - Luca Piersanti
- Laboratori Nazionali di Frascati dell'INFN Frascati Italy
| | - Marta Rovituso
- GSI Helmholtzzentrum für Schwerionenforschung Darmstadt Germany
| | - Christoph Schuy
- GSI Helmholtzzentrum für Schwerionenforschung Darmstadt Germany
| | | | | | | | - Chiara La Tessa
- NASA Space Radiation Laboratory Brookhaven National Laboratory Uptown NY USA
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Marafini M, Gasparini L, Mirabelli R, Pinci D, Patera V, Sciubba A, Spiriti E, Stoppa D, Traini G, Sarti A. MONDO: a neutron tracker for particle therapy secondary emission characterisation. Phys Med Biol 2017; 62:3299-3312. [PMID: 28350543 DOI: 10.1088/1361-6560/aa623a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tumour control is performed in particle therapy using particles and ions, whose high irradiation precision enhances the effectiveness of the treatment, while sparing the healthy tissue surrounding the target volume. Dose range monitoring devices using photons and charged particles produced by the beam interacting with the patient's body have already been proposed, but no attempt has been made yet to exploit the detection of the abundant neutron component. Since neutrons can release a significant dose far away from the tumour region, precise measurements of their flux, production energy and angle distributions are eagerly sought in order to improve the treatment planning system (TPS) software. It will thus be possible to predict not only the normal tissue toxicity in the target region, but also the risk of late complications in the whole body. The aforementioned issues underline the importance of an experimental effort devoted to the precise characterisation of neutron production, aimed at the measurement of their abundance, emission point and production energy. The technical challenges posed by a neutron detector aimed at high detection efficiency and good backtracking precision are addressed within the MONDO (monitor for neutron dose in hadrontherapy) project, whose main goal is to develop a tracking detector that can target fast and ultrafast neutrons. A full reconstruction of two consecutive elastic scattering interactions undergone by the neutrons inside the detector material will be used to measure their energy and direction. The preliminary results of an MC simulation performed using the FLUKA software are presented here, together with the DSiPM (digital SiPM) readout implementation. New detector readout implementations specifically tailored to the MONDO tracker are also discussed, and the neutron detection efficiency attainable with the proposed neutron tracking strategy are reported.
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Affiliation(s)
- M Marafini
- INFN Sezione di Roma, Rome, Italy. Museo Storico della Fisica e Centro Studi e Ricerche 'E. Fermi', Rome, Italy
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Kelleter L, Wrońska A, Besuglow J, Konefał A, Laihem K, Leidner J, Magiera A, Parodi K, Rusiecka K, Stahl A, Tessonnier T. Spectroscopic study of prompt-gamma emission for range verification in proton therapy. Phys Med 2017; 34:7-17. [PMID: 28131731 DOI: 10.1016/j.ejmp.2017.01.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/12/2016] [Accepted: 01/02/2017] [Indexed: 10/20/2022] Open
Abstract
We present the results of an investigation of the prompt-gamma emission from an interaction of a proton beam with phantom materials. Measurements were conducted with a novel setup allowing the precise selection of the investigated depth in the phantom, featuring three different materials composed of carbon, oxygen and hydrogen. We studied two beam energies of 70.54 and 130.87MeV and two detection angles: 90° and 120°. The results are presented in form of profiles of the prompt-gamma yield as a function of depth. In the analysis we focused on the transitions with the largest cross sections: 12C4.44→g.s. and 16O6.13→g.s.. We compare the profiles obtained under various irradiation conditions, with emphasis on the shape of the distal fall-off. The results are also compared to calculations including different cross-section models. They are in agreement with the model exploiting published cross-section data, but the comparison with the Talys model shows discrepancies.
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Affiliation(s)
| | - Aleksandra Wrońska
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland.
| | - Judith Besuglow
- Physics Institute 3B, RWTH Aachen University, Aachen, Germany
| | - Adam Konefał
- Department of Nuclear Physics and its Applications, Institute of Physics, University of Silesia, Katowice, Poland
| | - Karim Laihem
- Physics Institute 3B, RWTH Aachen University, Aachen, Germany
| | | | - Andrzej Magiera
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - Katia Parodi
- Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Katarzyna Rusiecka
- Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
| | - Achim Stahl
- Physics Institute 3B, RWTH Aachen University, Aachen, Germany
| | - Thomas Tessonnier
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany; Department of Radiation Oncology, Heidelberg University Clinic, Heidelberg, Germany
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Mattei I, Bini F, Collamati F, De Lucia E, Frallicciardi PM, Iarocci E, Mancini-Terracciano C, Marafini M, Muraro S, Paramatti R, Patera V, Piersanti L, Pinci D, Rucinski A, Russomando A, Sarti A, Sciubba A, Solfaroli Camillocci E, Toppi M, Traini G, Voena C, Battistoni G. Secondary radiation measurements for particle therapy applications: prompt photons produced by 4He, 12C and 16O ion beams in a PMMA target. Phys Med Biol 2017; 62:1438-1455. [PMID: 28114112 DOI: 10.1088/1361-6560/62/4/1438] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Charged particle beams are used in particle therapy (PT) to treat oncological patients due to their selective dose deposition in tissues with respect to the photons and electrons used in conventional radiotherapy. Heavy (Z > 1) PT beams can additionally be exploited for their high biological effectiveness in killing cancer cells. Nowadays, protons and carbon ions are used in PT clinical routines. Recently, interest in the potential application of helium and oxygen beams has been growing. With respect to protons, such beams are characterized by their reduced multiple scattering inside the body, increased linear energy transfer, relative biological effectiveness and oxygen enhancement ratio. The precision of PT demands online dose monitoring techniques, crucial to improving the quality assurance of any treatment: possible patient mis-positioning and biological tissue changes with respect to the planning CT scan could negatively affect the outcome of the therapy. The beam range confined in the irradiated target can be monitored thanks to the neutral or charged secondary radiation emitted by the interactions of hadron beams with matter. Among these secondary products, prompt photons are produced by nuclear de-excitation processes, and at present, different dose monitoring and beam range verification techniques based on prompt-γ detection are being proposed. It is hence of importance to perform γ yield measurement in therapeutic-like conditions. In this paper we report on the yields of prompt photons produced by the interaction of helium, carbon and oxygen ion beams with a poly-methyl methacrylate (PMMA) beam stopping target. The measurements were performed at the Heidelberg Ion-Beam Therapy Center (HIT) with beams of different energies. An LYSO scintillator, placed at [Formula: see text] and [Formula: see text] with respect to the beam direction, was used as the photon detector. The obtained γ yields for the carbon ion beams are compared with results from the literature, while no other results from helium and oxygen beams have been published yet. A discussion on the expected resolution of a slit camera detector is presented, demonstrating the feasibility of a prompt-γ-based monitoring technique for PT treatments using helium, carbon and oxygen ion beams.
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Yamaguchi M, Nagao Y, Satoh T, Sugai H, Sakai M, Arakawa K, Kawachi N. Monte Carlo simulation of photon emission below a few hundred kiloelectronvolts for beam monitoring in carbon ion therapy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:014301. [PMID: 28147655 DOI: 10.1063/1.4973986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The purpose of this study is to determine whether the main component of the low-energy (63-68 keV) particles emitted perpendicularly to the 12C beam from the 12C-irradiated region in a water phantom is secondary electron bremsstrahlung (SEB). Monte Carlo simulations of a 12C-beam (290 MeV/u) irradiated on a water phantom were performed. A detector was placed beside the water phantom with a lead collimator between the phantom and the detector. To move the Bragg-peak position, a binary filter was placed in an upper stream of the phantom. The energy distributions of the particles incident on the detector and those deposited in the detector were analyzed. The simulation was also performed with suppressed delta-ray and/or bremsstrahlung generation to identify the SEB components. It was found that the particles incident on the detector were predominantly photons and neutrons. The yields of the photons and energy deposition decreased with the suppression of SEB generation. It is concluded that one of the predominant components of the yields in the regions shallower than the Bragg-peak position is due to SEB generation, and these components become significantly smaller in regions deeper than the Bragg-peak position.
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Affiliation(s)
- Mitsutaka Yamaguchi
- Takasaki Advanced Radiation Research Institute, Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki-machi, Takasaki, Gunma, Japan
| | - Yuto Nagao
- Takasaki Advanced Radiation Research Institute, Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki-machi, Takasaki, Gunma, Japan
| | - Takahiro Satoh
- Takasaki Advanced Radiation Research Institute, Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki-machi, Takasaki, Gunma, Japan
| | - Hiroyuki Sugai
- Fukushima Prefectural Centre for Environmental Creation, 10-2 Fukasaku, Miharu-machi, Tamura-gun, Fukushima, Japan
| | - Makoto Sakai
- Gunma University Heavy Ion Medical Center, Gunma University, 3-39-22 Showa-machi, Maebashi, Gunma, Japan
| | - Kazuo Arakawa
- Takasaki Advanced Radiation Research Institute, Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki-machi, Takasaki, Gunma, Japan
| | - Naoki Kawachi
- Takasaki Advanced Radiation Research Institute, Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 1233 Watanuki-machi, Takasaki, Gunma, Japan
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20
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Huisman BFB, Létang JM, Testa É, Sarrut D. Accelerated prompt gamma estimation for clinical proton therapy simulations. Phys Med Biol 2016; 61:7725-7743. [DOI: 10.1088/0031-9155/61/21/7725] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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21
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Schumann A, Priegnitz M, Schoene S, Enghardt W, Rohling H, Fiedler F. From prompt gamma distribution to dose: a novel approach combining an evolutionary algorithm and filtering based on Gaussian-powerlaw convolutions. Phys Med Biol 2016; 61:6919-6934. [DOI: 10.1088/0031-9155/61/19/6919] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Durante M, Paganetti H. Nuclear physics in particle therapy: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:096702. [PMID: 27540827 DOI: 10.1088/0034-4885/79/9/096702] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Charged particle therapy has been largely driven and influenced by nuclear physics. The increase in energy deposition density along the ion path in the body allows reducing the dose to normal tissues during radiotherapy compared to photons. Clinical results of particle therapy support the physical rationale for this treatment, but the method remains controversial because of the high cost and of the lack of comparative clinical trials proving the benefit compared to x-rays. Research in applied nuclear physics, including nuclear interactions, dosimetry, image guidance, range verification, novel accelerators and beam delivery technologies, can significantly improve the clinical outcome in particle therapy. Measurements of fragmentation cross-sections, including those for the production of positron-emitting fragments, and attenuation curves are needed for tuning Monte Carlo codes, whose use in clinical environments is rapidly increasing thanks to fast calculation methods. Existing cross sections and codes are indeed not very accurate in the energy and target regions of interest for particle therapy. These measurements are especially urgent for new ions to be used in therapy, such as helium. Furthermore, nuclear physics hardware developments are frequently finding applications in ion therapy due to similar requirements concerning sensors and real-time data processing. In this review we will briefly describe the physics bases, and concentrate on the open issues.
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Affiliation(s)
- Marco Durante
- Trento Institute for Fundamental Physics and Applications (TIFPA), National Institute of Nuclear Physics (INFN), University of Trento, Via Sommarive 14, 38123 Povo (TN), Italy. Department of Physics, University Federico II, Naples, Italy
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Solevi P, Muñoz E, Solaz C, Trovato M, Dendooven P, Gillam JE, Lacasta C, Oliver JF, Rafecas M, Torres-Espallardo I, Llosá G. Performance of MACACO Compton telescope for ion-beam therapy monitoring: first test with proton beams. Phys Med Biol 2016; 61:5149-65. [DOI: 10.1088/0031-9155/61/14/5149] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Dedes G, Parodi K. Monte Carlo Simulations of Particle Interactions with Tissue in Carbon Ion Therapy. Int J Part Ther 2016; 2:447-458. [PMID: 31772955 PMCID: PMC6874200 DOI: 10.14338/ijpt-15-00021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 12/08/2015] [Indexed: 11/21/2022] Open
Abstract
Monte Carlo simulations are increasingly considered the most accurate tool for calculating particle interactions with tissue. This contribution reviews the basics of Monte Carlo methods and their emerging role for application to several areas of macroscopic simulation in the worldwide rapidly growing field of carbon ion therapy, spanning from dosimetric calculations to imaging of secondary radiation.
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Affiliation(s)
- George Dedes
- Department of Medical Physics, Ludwig-Maximilians-University, Munich, Germany
| | - Katia Parodi
- Department of Medical Physics, Ludwig-Maximilians-University, Munich, Germany
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25
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Pinto M, Dauvergne D, Freud N, Krimmer J, Létang JM, Testa E. Assessment of Geant4 Prompt-Gamma Emission Yields in the Context of Proton Therapy Monitoring. Front Oncol 2016; 6:10. [PMID: 26858937 PMCID: PMC4729887 DOI: 10.3389/fonc.2016.00010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 01/11/2016] [Indexed: 11/13/2022] Open
Abstract
Monte Carlo tools have been long used to assist the research and development of solutions for proton therapy monitoring. The present work focuses on the prompt-gamma emission yields by comparing experimental data with the outcomes of the current version of Geant4 using all applicable proton inelastic models. For the case in study and using the binary cascade model, it was found that Geant4 overestimates the prompt-gamma emission yields by 40.2 ± 0.3%, even though it predicts the prompt-gamma profile length of the experimental profile accurately. In addition, the default implementations of all proton inelastic models show an overestimation in the number of prompt gammas emitted. Finally, a set of built-in options and physically sound Geant4 source code changes have been tested in order to try to improve the discrepancy observed. A satisfactory agreement was found when using the QMD model with a wave packet width equal to 1.3 fm2.
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Affiliation(s)
- Marco Pinto
- CNRS/IN2P3 UMR 5822, IPNL, Université de Lyon, Université Lyon 1 , Villeurbanne , France
| | - Denis Dauvergne
- CNRS/IN2P3 UMR 5822, IPNL, Université de Lyon, Université Lyon 1 , Villeurbanne , France
| | - Nicolas Freud
- CREATIS, CNRS UMR 5220, INSERM U1044, INSA-Lyon, Centre Léon Bérard, Université de Lyon, Université Lyon 1 , Lyon , France
| | - Jochen Krimmer
- CNRS/IN2P3 UMR 5822, IPNL, Université de Lyon, Université Lyon 1 , Villeurbanne , France
| | - Jean M Létang
- CREATIS, CNRS UMR 5220, INSERM U1044, INSA-Lyon, Centre Léon Bérard, Université de Lyon, Université Lyon 1 , Lyon , France
| | - Etienne Testa
- CNRS/IN2P3 UMR 5822, IPNL, Université de Lyon, Université Lyon 1 , Villeurbanne , France
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26
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Battistoni G. Nuclear physics and particle therapy. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201611705001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Kraan AC. Range Verification Methods in Particle Therapy: Underlying Physics and Monte Carlo Modeling. Front Oncol 2015; 5:150. [PMID: 26217586 PMCID: PMC4493660 DOI: 10.3389/fonc.2015.00150] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 06/17/2015] [Indexed: 01/27/2023] Open
Abstract
Hadron therapy allows for highly conformal dose distributions and better sparing of organs-at-risk, thanks to the characteristic dose deposition as function of depth. However, the quality of hadron therapy treatments is closely connected with the ability to predict and achieve a given beam range in the patient. Currently, uncertainties in particle range lead to the employment of safety margins, at the expense of treatment quality. Much research in particle therapy is therefore aimed at developing methods to verify the particle range in patients. Non-invasive in vivo monitoring of the particle range can be performed by detecting secondary radiation, emitted from the patient as a result of nuclear interactions of charged hadrons with tissue, including β (+) emitters, prompt photons, and charged fragments. The correctness of the dose delivery can be verified by comparing measured and pre-calculated distributions of the secondary particles. The reliability of Monte Carlo (MC) predictions is a key issue. Correctly modeling the production of secondaries is a non-trivial task, because it involves nuclear physics interactions at energies, where no rigorous theories exist to describe them. The goal of this review is to provide a comprehensive overview of various aspects in modeling the physics processes for range verification with secondary particles produced in proton, carbon, and heavier ion irradiation. We discuss electromagnetic and nuclear interactions of charged hadrons in matter, which is followed by a summary of some widely used MC codes in hadron therapy. Then, we describe selected examples of how these codes have been validated and used in three range verification techniques: PET, prompt gamma, and charged particle detection. We include research studies and clinically applied methods. For each of the techniques, we point out advantages and disadvantages, as well as clinical challenges still to be addressed, focusing on MC simulation aspects.
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Affiliation(s)
- Aafke Christine Kraan
- Department of Physics, National Institute for Nuclear Physics (INFN), University of Pisa, Pisa, Italy
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