- Email: [email protected]
CT imaging system using GATE Monte Carlo simulation
Abstracts / Physica Medica 42 (2017) 1–50
virtual machine based on the multi-purpose proton nozzle. In the wobbling mode, scanning mode, and scanning mode with dynamic MLC, the neutron dose equivalent generated through the nozzle was compared using the 12 cm diameter receptor. The receptors were located at the distance of r = 0, 25, 50, 100, 150, and 200 cm from the isocenter. In both field size conditions, the neutron dose equivalent in the scanning mode were 96.6%, 98.7%, 98.7%, 98.4%, 98.2%, and 97.9% lower than the wobbling mode in each receptor position, respectively. However, the neutron doses equivalent using line scanning with MLC to reduce the lateral penumbral width were 53.0%, 91.8%, 90.0%, 90.2%, 92.0%, and 91.6%, respectively, compared to the wobbling mode. The use of dynamic MLC in the scanning increases the neutron dose equivalent, but the use of dynamic MLC can reduce the dose to the organ at risk around the target and avoid disadvantages of the conventional scanning proton therapy [2]. However, according to the results of this study, secondary cancer caused by the effect of neutron dose increased when scanning with dynamic MLC is not negligible [3]
References 1. Agostinelli S, Allison J, Amako K, et al. GEANT4 – a simulation toolkit. Nucl Instrum Methods A 2003;504:250–303. 2. Safai S, Bortfeld T, Engelsman M. Comparison between the lateral penumber of a collimated double-scattered beam and uncollimated scanning beam in proton radiotherapy. Phys Med Biol 2008;53:1729–50. 3. Jarlskog CZ, Paganetti H. Risk of developing second cancer from neutron dose in proton therapy as function of field characteristics, organ, and patient age. Int J Radiat Oncol Biol Phys 2008;72:228–35. http://dx.doi.org/10.1016/j.ejmp.2017.09.142
Abstract ID: 67 MC codes and range monitoring in particle therapy: The case of secondary charged particles S. Muraro g,*, G. Battistoni f, E. De Lucia e, C. Mancini-Terracciano c, M. Marafini b,c, I. Mattei f, R. Mirabelli a,c, A. Sarti d,e,c, A. Sciubba d,b,c, E. Solfaroli Camillocci a,c, M. Toppi e, G. Traini a,c, S.M. Valle f,h, C. Voena c, V. Patera d,b,c a
Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Rome, Italy c INFN Sezione di Roma, Roma, Italy d Dipartimento di Scienze di Base e Applicate per l’Ingegneria, Sapienza University, Roma, Italy e INFN Sezione Laboratori Nazionali di Frascati, Frascati (Roma), Italy f INFN Sezione di Milano, Milano, Italy g INFN Sezione di Pisa, Pisa, Italy h Università degli Studi di Milano, Milano, Italy ⇑ presenting author. b
Particle therapy planning gets fundamental information from MC codes. Its millimetric precision needs the assurance of the successfulness of the treatment session. Different range monitoring techniques are under development exploiting secondary particles which are generated in the patient during the treatment: prompt gammas, annihilation gammas from beta+ induced activity, charged fragments. The yield of produced particles and their propagation in the human tissue must be studied with MC codes. In this contribution, in the framework of the INSIDE collaboration (Innovative Solutions for In-beam Dosimetry in hadrontherapy), the
49
case of secondary charged fragments emission during the treatment is considered[1]. A detector named Dose Profiler (DP), able to track secondary charged fragments (mainly protons) emitted at large angles with respect to the beam direction, is under construction and test. The tracker is made by six layers (20 20 cm2) of BCF-12 square scintillating fibres (500 lm) coupled to Silicon Photo-Multipliers, followed by two plastic scintillator layers of 6 mm thickness. The detector characterization with cosmic rays has been performed and a calibration data taking campaign with protons is currently undergoing. The attenuation of the secondary charged particles emission profile due to the crossed material is studied and parametrized with the FLUKA MC code. A full simulation of a treatment in a realistic patient-detector system and the secondary charged fragments reconstruction is presented. Track reconstruction is performed by means of a Kalman filter algorithm using the GenFit code. The on-line operation of DP requires the real-time reconstruction of the amount of material crossed in the patient by each detected proton. This task will be accomplished using FRED, a fast GPU-MC code.
References 1. Traini G et al. Design of a new tracking device for on-line beam range monitor in carbon therapy. Phys Med 2017;34:18–27. doi:10.1016/j.ejmp.2017.01.004. http://dx.doi.org/10.1016/j.ejmp.2017.09.143
Abstract ID: 120 Performance evaluation of the Siemens Biograph6 PET/CT imaging system using GATE Monte Carlo simulation Hanieh Sadat Jozi a,*, Saba Fakhroo a, Elham Saeedzadeh a, Parham Geramifar b a Science and Research Branch, Islamic Azad University, Department of medical radiation engineering, Tehran, Iran b Research Center For Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran ⇑ Corresponding author.
Introduction. As the performance of a PET scanner depends not only on the scintillating material but also on the scanner design. [1], researchers use the Monte Carlo simulation in designing the scanners or evaluating their performance and optimizing the functional parameters before commercialization. In this study, was simulated a clinical PET/CT scanner with LSO crystal using Monte Carlo method for the purpose of investigation of the performance and obtaining the optimal patient injected activity. Materials and methods. The PET scanner of the Siemens Biograph6 PET/CT system was simulated using GATE Monte Carlo simulation code [2]. Sensitivity, scatter fraction (SF) and the noise equivalent count rate (NECR) metric were derived by the simulation of the standard sensitivity and count rate phantom in accordance with the NEMA NU 2-2001 protocol. GATE results were compared and validated against the published data in accordance with the vendor’s specifications. Results. The simulated NEMA standard phantoms showed scatter fraction and sensitivity of 36%, and 4.16 cps/kBq respectively. The difference between the measured and simulated sensitivity of system was less than 1%, and scatter fraction was within the accepted range. Also maximum NECR value in 35 kBq/cc activity concentration was 92 kcps results in less than 5% difference between simulated and measured data.
50
Abstracts / Physica Medica 42 (2017) 1–50
Conclusion. Our results demonstrated an excellent agreement between GATE simulated data and measured data. The evaluation of the PET scanner performance in the Siemens Biograph6 PET/CT scanner using Monte Carlo modeling shows that GATE is adequately accurate to describe the performance of PET system. Keywords: Monte Carlo; GATE; PET scanner References
Abstract ID: 54 The application of the FLUKA Monte Carlo code in medical physics Giuseppe Battistoni a,*, Francesca Ballarini b,c, Julia Bauer d, Till Böhlen e, Mario Pietro Carante b,c, Francesco Cerutti f, Mary Chin g, Ricardo Dos Santos Augusto f,h, Andrea Fontana c, Alessia Embriaco b,c, Alfredo Ferrari f, Wioletta Kozlowska f, Giuseppe Magro i, Andrea Mairani i,j, Katia Parodi h, Pablo Ortega f, Paola Sala a, Philippe Schoofs f, Thomas Tessonier h, Vasilis Vlachoudis f a
INFN, Sezione di Milano, Italy University of Pavia, Pavia, Italy c INFN, Sezione di Pavia, Pavia, Italy d Uniklinikum Heidelberg, Heidelberg, Germany e Medaustron, Wiener Neustadt, Austria f CERN, Geneva, Switzerland g TRIUMF, Canada h Ludwig Maximilians Universität, München, Germany i CNAO, Pavia, Italy j HIT, Heildeberg, Germany ⇑ presenting author. b
1. Ghazanfari N et al. Quantitative assessment of crystal material and size on the performance of rotating dual head small animal PET scanners using Monte Carlo modeling. Hell J Nucl Med 2012;15(1):33–9. 2. OpenGATE Collaboration, GATE Users Guide, Version 7.1, http:// www-lphe.epfl.ch/GATE. http://dx.doi.org/10.1016/j.ejmp.2017.09.144
Abstract ID: 19 Validation of the Monte Carlo GATE platform for the dosimetry of ocular protontherapy Laoues Mostafa a,b,*, Khelifi Rachid b, Sidi Moussa Ahmed a,b a
Laboratory of Nuclear Science and Radiation-Matter Interactions (LSNIRM) USTHB, Bab Ezzouar 16111, Algiers, Algeria b Laboratory of Theoretical Physics and Radiation-Matter Interactions (LPTHIRM) USDB, Soumaa 09000, Blida, Algeria ⇑ Corresponding author. E-mail: [email protected] The aim of this work consisted to validate the Monte Carlo GATE platform in dose distributions of a proton beam on a mathematical model of the human eye. As a first step, a recommended 62 MeV proton beam for the treatment of ocular melanoma was simulated with GATE to check its aptitude to reproduce experimental measurements. In the second step, this beam was applied to a mathematical model of the human eye was defined precisely with real dimensions and densities. Depth-dose profile, lateral profile, dosimetric parameters according to international recommendations, and absolute dose in tumor and each organ were calculated and compared to other therapeutic techniques and Monte Carlo codes. A total of 106 incident protons were simulated in 20 min on a single i5 3.2 GHz CPU. Relative comparisons of percentage depth-dose and lateral profiles, performed between measured beam data and the simulated, show an agreement of the order of 2% in dose and 0.1 mm in range accuracy. These comparisons carried out with and without beam-modifying device, yield results compatible to the required precision in ocular melanoma treatments. Doses distributions issued from calculations and measurements were also compared. GATE platform show better results compared to other Monte Carlo codes. Results obtained from this study show that protontherapy is the most suitable treatment for ocular melanoma due to the unique property of its beam (Bragg peak). The ease of use, reproducibility and speed of GATE allows it to be used as an integrated tool for modeling imaging, dosimetry and processing in the same simulation platform. Ocular protontherapy offers excellent levels of eye retention, even in unfavorable cases such as large tumors. http://dx.doi.org/10.1016/j.ejmp.2017.09.145
Monte Carlo codes are increasingly spreading in medical physics community due to their capability of performing a detailed description of radiation transport and interaction with matter. This contribution will address the recent developments of the FLUKA code and its practical application in medical physics. FLUKA is being used in radiation therapy and nuclear medicine. At present, it is of particular interest in the context of particle therapy, thanks to the development of accurate and reliable physical models capable of handling all components of the expected radiation field. At the same time, the code can be interfaced to different radiobiological models. These features become extremely important for correctly performing not only physical but also biologically based dose calculations, especially in cases where ions heavier than protons are involved. At the same time, in order to support the application of FLUKA in hospital-based environments, the FLUKA graphical interface has been enhanced with the capability of translating CT DICOM images into voxel-based computational phantoms in a fast and wellstructured way. The interface is capable of importing also radiotherapy treatment data described in DICOM RT standard. Therefore, the FLUKA code not only is a reliable instrument for the simulation of therapeutic beams, but it is also used in some of the leading European hadron therapy centers as an accurate tool for Treatment Planning verification and correction. In addition, it allows an accurate prediction of emerging secondary radiation and this is of the utmost importance in innovative areas of research aiming at in vivo treatment verification. Here we shall review the features of the FLUKA code, pointing out the recent refinements of the nuclear models, relevant for the therapeutic energy interval, which lead to an improved description of the mixed radiation field. Benchmarks against experimental data with both proton and ion beams will be shown. Examples of clinical application will be presented, together with a review of some results in medical physics research. http://dx.doi.org/10.1016/j.ejmp.2017.09.146
virtual machine based on the multi-purpose proton nozzle. In the wobbling mode, scanning mode, and scanning mode with dynamic MLC, the neutron dose equivalent generated through the nozzle was compared using the 12 cm diameter receptor. The receptors were located at the distance of r = 0, 25, 50, 100, 150, and 200 cm from the isocenter. In both field size conditions, the neutron dose equivalent in the scanning mode were 96.6%, 98.7%, 98.7%, 98.4%, 98.2%, and 97.9% lower than the wobbling mode in each receptor position, respectively. However, the neutron doses equivalent using line scanning with MLC to reduce the lateral penumbral width were 53.0%, 91.8%, 90.0%, 90.2%, 92.0%, and 91.6%, respectively, compared to the wobbling mode. The use of dynamic MLC in the scanning increases the neutron dose equivalent, but the use of dynamic MLC can reduce the dose to the organ at risk around the target and avoid disadvantages of the conventional scanning proton therapy [2]. However, according to the results of this study, secondary cancer caused by the effect of neutron dose increased when scanning with dynamic MLC is not negligible [3]
References 1. Agostinelli S, Allison J, Amako K, et al. GEANT4 – a simulation toolkit. Nucl Instrum Methods A 2003;504:250–303. 2. Safai S, Bortfeld T, Engelsman M. Comparison between the lateral penumber of a collimated double-scattered beam and uncollimated scanning beam in proton radiotherapy. Phys Med Biol 2008;53:1729–50. 3. Jarlskog CZ, Paganetti H. Risk of developing second cancer from neutron dose in proton therapy as function of field characteristics, organ, and patient age. Int J Radiat Oncol Biol Phys 2008;72:228–35. http://dx.doi.org/10.1016/j.ejmp.2017.09.142
Abstract ID: 67 MC codes and range monitoring in particle therapy: The case of secondary charged particles S. Muraro g,*, G. Battistoni f, E. De Lucia e, C. Mancini-Terracciano c, M. Marafini b,c, I. Mattei f, R. Mirabelli a,c, A. Sarti d,e,c, A. Sciubba d,b,c, E. Solfaroli Camillocci a,c, M. Toppi e, G. Traini a,c, S.M. Valle f,h, C. Voena c, V. Patera d,b,c a
Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Rome, Italy c INFN Sezione di Roma, Roma, Italy d Dipartimento di Scienze di Base e Applicate per l’Ingegneria, Sapienza University, Roma, Italy e INFN Sezione Laboratori Nazionali di Frascati, Frascati (Roma), Italy f INFN Sezione di Milano, Milano, Italy g INFN Sezione di Pisa, Pisa, Italy h Università degli Studi di Milano, Milano, Italy ⇑ presenting author. b
Particle therapy planning gets fundamental information from MC codes. Its millimetric precision needs the assurance of the successfulness of the treatment session. Different range monitoring techniques are under development exploiting secondary particles which are generated in the patient during the treatment: prompt gammas, annihilation gammas from beta+ induced activity, charged fragments. The yield of produced particles and their propagation in the human tissue must be studied with MC codes. In this contribution, in the framework of the INSIDE collaboration (Innovative Solutions for In-beam Dosimetry in hadrontherapy), the
49
case of secondary charged fragments emission during the treatment is considered[1]. A detector named Dose Profiler (DP), able to track secondary charged fragments (mainly protons) emitted at large angles with respect to the beam direction, is under construction and test. The tracker is made by six layers (20 20 cm2) of BCF-12 square scintillating fibres (500 lm) coupled to Silicon Photo-Multipliers, followed by two plastic scintillator layers of 6 mm thickness. The detector characterization with cosmic rays has been performed and a calibration data taking campaign with protons is currently undergoing. The attenuation of the secondary charged particles emission profile due to the crossed material is studied and parametrized with the FLUKA MC code. A full simulation of a treatment in a realistic patient-detector system and the secondary charged fragments reconstruction is presented. Track reconstruction is performed by means of a Kalman filter algorithm using the GenFit code. The on-line operation of DP requires the real-time reconstruction of the amount of material crossed in the patient by each detected proton. This task will be accomplished using FRED, a fast GPU-MC code.
References 1. Traini G et al. Design of a new tracking device for on-line beam range monitor in carbon therapy. Phys Med 2017;34:18–27. doi:10.1016/j.ejmp.2017.01.004. http://dx.doi.org/10.1016/j.ejmp.2017.09.143
Abstract ID: 120 Performance evaluation of the Siemens Biograph6 PET/CT imaging system using GATE Monte Carlo simulation Hanieh Sadat Jozi a,*, Saba Fakhroo a, Elham Saeedzadeh a, Parham Geramifar b a Science and Research Branch, Islamic Azad University, Department of medical radiation engineering, Tehran, Iran b Research Center For Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran ⇑ Corresponding author.
Introduction. As the performance of a PET scanner depends not only on the scintillating material but also on the scanner design. [1], researchers use the Monte Carlo simulation in designing the scanners or evaluating their performance and optimizing the functional parameters before commercialization. In this study, was simulated a clinical PET/CT scanner with LSO crystal using Monte Carlo method for the purpose of investigation of the performance and obtaining the optimal patient injected activity. Materials and methods. The PET scanner of the Siemens Biograph6 PET/CT system was simulated using GATE Monte Carlo simulation code [2]. Sensitivity, scatter fraction (SF) and the noise equivalent count rate (NECR) metric were derived by the simulation of the standard sensitivity and count rate phantom in accordance with the NEMA NU 2-2001 protocol. GATE results were compared and validated against the published data in accordance with the vendor’s specifications. Results. The simulated NEMA standard phantoms showed scatter fraction and sensitivity of 36%, and 4.16 cps/kBq respectively. The difference between the measured and simulated sensitivity of system was less than 1%, and scatter fraction was within the accepted range. Also maximum NECR value in 35 kBq/cc activity concentration was 92 kcps results in less than 5% difference between simulated and measured data.
50
Abstracts / Physica Medica 42 (2017) 1–50
Conclusion. Our results demonstrated an excellent agreement between GATE simulated data and measured data. The evaluation of the PET scanner performance in the Siemens Biograph6 PET/CT scanner using Monte Carlo modeling shows that GATE is adequately accurate to describe the performance of PET system. Keywords: Monte Carlo; GATE; PET scanner References
Abstract ID: 54 The application of the FLUKA Monte Carlo code in medical physics Giuseppe Battistoni a,*, Francesca Ballarini b,c, Julia Bauer d, Till Böhlen e, Mario Pietro Carante b,c, Francesco Cerutti f, Mary Chin g, Ricardo Dos Santos Augusto f,h, Andrea Fontana c, Alessia Embriaco b,c, Alfredo Ferrari f, Wioletta Kozlowska f, Giuseppe Magro i, Andrea Mairani i,j, Katia Parodi h, Pablo Ortega f, Paola Sala a, Philippe Schoofs f, Thomas Tessonier h, Vasilis Vlachoudis f a
INFN, Sezione di Milano, Italy University of Pavia, Pavia, Italy c INFN, Sezione di Pavia, Pavia, Italy d Uniklinikum Heidelberg, Heidelberg, Germany e Medaustron, Wiener Neustadt, Austria f CERN, Geneva, Switzerland g TRIUMF, Canada h Ludwig Maximilians Universität, München, Germany i CNAO, Pavia, Italy j HIT, Heildeberg, Germany ⇑ presenting author. b
1. Ghazanfari N et al. Quantitative assessment of crystal material and size on the performance of rotating dual head small animal PET scanners using Monte Carlo modeling. Hell J Nucl Med 2012;15(1):33–9. 2. OpenGATE Collaboration, GATE Users Guide, Version 7.1, http:// www-lphe.epfl.ch/GATE. http://dx.doi.org/10.1016/j.ejmp.2017.09.144
Abstract ID: 19 Validation of the Monte Carlo GATE platform for the dosimetry of ocular protontherapy Laoues Mostafa a,b,*, Khelifi Rachid b, Sidi Moussa Ahmed a,b a
Laboratory of Nuclear Science and Radiation-Matter Interactions (LSNIRM) USTHB, Bab Ezzouar 16111, Algiers, Algeria b Laboratory of Theoretical Physics and Radiation-Matter Interactions (LPTHIRM) USDB, Soumaa 09000, Blida, Algeria ⇑ Corresponding author. E-mail: [email protected] The aim of this work consisted to validate the Monte Carlo GATE platform in dose distributions of a proton beam on a mathematical model of the human eye. As a first step, a recommended 62 MeV proton beam for the treatment of ocular melanoma was simulated with GATE to check its aptitude to reproduce experimental measurements. In the second step, this beam was applied to a mathematical model of the human eye was defined precisely with real dimensions and densities. Depth-dose profile, lateral profile, dosimetric parameters according to international recommendations, and absolute dose in tumor and each organ were calculated and compared to other therapeutic techniques and Monte Carlo codes. A total of 106 incident protons were simulated in 20 min on a single i5 3.2 GHz CPU. Relative comparisons of percentage depth-dose and lateral profiles, performed between measured beam data and the simulated, show an agreement of the order of 2% in dose and 0.1 mm in range accuracy. These comparisons carried out with and without beam-modifying device, yield results compatible to the required precision in ocular melanoma treatments. Doses distributions issued from calculations and measurements were also compared. GATE platform show better results compared to other Monte Carlo codes. Results obtained from this study show that protontherapy is the most suitable treatment for ocular melanoma due to the unique property of its beam (Bragg peak). The ease of use, reproducibility and speed of GATE allows it to be used as an integrated tool for modeling imaging, dosimetry and processing in the same simulation platform. Ocular protontherapy offers excellent levels of eye retention, even in unfavorable cases such as large tumors. http://dx.doi.org/10.1016/j.ejmp.2017.09.145
Monte Carlo codes are increasingly spreading in medical physics community due to their capability of performing a detailed description of radiation transport and interaction with matter. This contribution will address the recent developments of the FLUKA code and its practical application in medical physics. FLUKA is being used in radiation therapy and nuclear medicine. At present, it is of particular interest in the context of particle therapy, thanks to the development of accurate and reliable physical models capable of handling all components of the expected radiation field. At the same time, the code can be interfaced to different radiobiological models. These features become extremely important for correctly performing not only physical but also biologically based dose calculations, especially in cases where ions heavier than protons are involved. At the same time, in order to support the application of FLUKA in hospital-based environments, the FLUKA graphical interface has been enhanced with the capability of translating CT DICOM images into voxel-based computational phantoms in a fast and wellstructured way. The interface is capable of importing also radiotherapy treatment data described in DICOM RT standard. Therefore, the FLUKA code not only is a reliable instrument for the simulation of therapeutic beams, but it is also used in some of the leading European hadron therapy centers as an accurate tool for Treatment Planning verification and correction. In addition, it allows an accurate prediction of emerging secondary radiation and this is of the utmost importance in innovative areas of research aiming at in vivo treatment verification. Here we shall review the features of the FLUKA code, pointing out the recent refinements of the nuclear models, relevant for the therapeutic energy interval, which lead to an improved description of the mixed radiation field. Benchmarks against experimental data with both proton and ion beams will be shown. Examples of clinical application will be presented, together with a review of some results in medical physics research. http://dx.doi.org/10.1016/j.ejmp.2017.09.146