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Zhang J, Qi P, Wang J. Multi-objective genetic algorithm for synchrotron radiation beamline optimization. JOURNAL OF SYNCHROTRON RADIATION 2023; 30:51-56. [PMID: 36601925 PMCID: PMC9814073 DOI: 10.1107/s1600577522010050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 10/17/2022] [Indexed: 06/17/2023]
Abstract
In beamline design, there are many floating parameters that need to be tuned; manual optimization is time-consuming and laborious work, and it is also difficult to obtain well optimized results. Moreover, there are always several objectives that need to be considered and optimized at the same time, making the problem more complicated. For example, asking for both the flux and energy to be as large as possible is a usual requirement, but the changing trends of these two variables are often contradictory. In this study, a novel optimization method based on a multi-objective genetic algorithm is introduced, the first attempt to optimize a beamline with multiple objectives. In order to verify this method, beamline ID17 of the European Synchrotron Radiation Facility (ESRF) is taken as an example for simulation, with energy and dose rate as objectives. The result shows that this method can be effective for beamline optimization, and an optimal solution set can be obtained within 30 generations. For the solutions whose objectives are both improved compared with those of ESRF beamline ID17, the maximums of energy and dose rate increase by around 7% and 20%, respectively.
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Affiliation(s)
- Junyu Zhang
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Pengyuan Qi
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, People’s Republic of China
| | - Jike Wang
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, People’s Republic of China
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2
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Shende R, Dhoble S, Gupta G. Geometrical source modeling of 6MV flattening-filter-free (FFF) beam from TrueBeam linear accelerator and its commissioning validation using Monte Carlo simulation approach for radiotherapy. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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3
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Keshmiri S, Brocard S, Serduc R, Adam JF. A high resolution dose calculation engine for x-ray microbeams radiation therapy. Med Phys 2022; 49:3999-4017. [PMID: 35342953 PMCID: PMC9322281 DOI: 10.1002/mp.15637] [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: 11/10/2021] [Revised: 03/04/2022] [Accepted: 03/08/2022] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Microbeam radiation therapy (MRT) is a treatment modality based on spatial fractionation of synchrotron generated x-rays into parallel, high dose, microbeams of a few microns width. MRT is still an under-development radiosurgery technique for which, promising preclinical results on brain tumors and epilepsy encourages its clinical transfer. PURPOSE A safe clinical transfer of MRT needs a specific treatment planning system (TPS) that provides accurate dose calculations in human patients, taking into account the MRT beams properties (high dose gradients, spatial fractionation, polarization effects). So far, the most advanced MRT treatment planning system, based on a hybrid dose calculation algorithm, is limited to a macroscopic rendering of the dose and does not account for the complex dose distribution inherent to MRT if delivered as conformal irradiations with multiple incidences. For overcoming these limitations, a multi-scale full Monte-Carlo calculation engine called penMRT has been developed and benchmarked against two general purpose Monte Carlo codes: penmain based on PENELOPE and Gate based on Geant4. METHODS PenMRT, is based on the PENELOPE (2018) Monte Carlo (MC) code, modified to take into account the voxelized geometry of the patients (CT-scans) and offering an adaptive micrometric dose calculation grid independent to the CT size, location and orientation. The implementation of the dynamic memory allocation in penMRT, makes the simulations feasible within a huge number of dose scoring bins. The possibility of using a source replication approach to simulate arrays of microbeams, and the parallelization using OpenMPI have been added to penMRT in order to increase the calculation speed for clinical usages. This engine can be implemented in a TPS as a dose calculation core. RESULTS The performance tests highlight the reliability of penMRT to be used for complex irradiation conditions in MRT. The benchmarking against a standard PENELOPE code did not show any significant difference for calculations in centimetric beams, for a single microbeam and for a microbeam array. The comparisons between penMRT and Gate as an independent MC code did not show any difference in the beam paths, whereas in valley regions, relative differences between the two codes rank from 1 to 7.5% which are probably due to the differences in physics lists that are used in these two codes. The reliability of the source replication approach has also been tested and validated with an underestimation of no more than 0.6% in low dose areas. CONCLUSIONS Good agreements (a relative difference between 0 to 8%) were found when comparing calculated peak to valley dose ratio (PVDR) values using penMRT, for irradiations with a full microbeam array, with calculated values in the literature. The high-resolution calculated dose maps obtained with penMRT are used to extract differential and cumulative dose-volume histograms (DVHs) and analyze treatment plans with much finer metrics regarding the irradiation complexity. To our knowledge, these are the first high-resolution dose maps and associated DVHs ever obtained for cross-fired microbeams irradiation, which is bringing a significant added value to the field of treatment planning in spatially fractionated radiation therapy. This article is protected by copyright. All rights reserved.
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Affiliation(s)
| | - Sylvan Brocard
- Univ. Grenoble Alpes, INSERM, UA07 STROBE, Grenoble, 38000, France
| | - Raphaël Serduc
- Univ. Grenoble Alpes, INSERM, UA07 STROBE, Grenoble, 38000, France.,Centre Hospitalier Universitaire de Grenoble, Grenoble, 38000, France
| | - Jean-François Adam
- Univ. Grenoble Alpes, INSERM, UA07 STROBE, Grenoble, 38000, France.,Centre Hospitalier Universitaire de Grenoble, Grenoble, 38000, France
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4
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Wright MD, Romanelli P, Bravin A, Le Duc G, Brauer-Krisch E, Requardt H, Bartzsch S, Hlushchuk R, Laissue JA, Djonov V. Non-conventional Ultra-High Dose Rate (FLASH) Microbeam Radiotherapy Provides Superior Normal Tissue Sparing in Rat Lung Compared to Non-conventional Ultra-High Dose Rate (FLASH) Radiotherapy. Cureus 2021; 13:e19317. [PMID: 35223216 PMCID: PMC8864723 DOI: 10.7759/cureus.19317] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2021] [Indexed: 12/12/2022] Open
Abstract
Conventional radiotherapy is a widely used non-invasive form of treatment for many types of cancer. However, due to a low threshold in the lung for radiation-induced normal tissue damage, it is of less utility in treating lung cancer. For this reason, surgery is the preferred treatment for lung cancer, which has the detriment of being highly invasive. Non-conventional ultra-high dose rate (FLASH) radiotherapy is currently of great interest in the radiotherapy community due to demonstrations of reduced normal tissue toxicity in lung and other anatomy. This study investigates the effects of FLASH microbeam radiotherapy, which in addition to ultra-high dose rate incorporates a spatial segmentation of the radiation field, on the normal lung tissue of rats. With a focus on fibrotic damage, this work demonstrates that FLASH microbeam radiotherapy provides an order of magnitude increase in normal tissue radio-resistance compared to FLASH radiotherapy. This result suggests FLASH microbeam radiotherapy holds promise for much improved non-invasive control of lung cancer.
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Affiliation(s)
- Michael D Wright
- Ginzton Technology Center, Varian Medical Systems, Palo Alto, USA.,Research & Development Center, Avail Medical Devices, Roseville, USA
| | | | - Alberto Bravin
- Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble, FRA
| | - Geraldine Le Duc
- Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble, FRA.,Pharmaceutics, NH TherAguix, Lyon, FRA
| | - Elke Brauer-Krisch
- Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble, FRA
| | - Herwig Requardt
- Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble, FRA
| | - Stefan Bartzsch
- Department of Radiation Oncology, School of Medicine, Technical University of Munich, Munich, DEU.,Institute for Radiation Medicine, Helmholtz Centre Munich, Munich, DEU
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5
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Laissue JA. Elke Bräuer-Krisch: dedication, creativity and generosity: May 17, 1961-September 10, 2018. Int J Radiat Biol 2021; 98:280-287. [PMID: 34129423 DOI: 10.1080/09553002.2021.1941385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE This extraordinary woman worked her professional way from a radiation protection engineer to become the successful principal investigator of a prestigious international European project for a new radiation therapy (ERC Synergy grant, HORIZON 2020). The evaluation of the submitted proposal was very positive. The panel proposed that it be funded. Elke tragically passed away a few days before this conclusion of the panel. The present account describes her gradual career development; it includes many episodes that Elke personally chronicled in her curriculum of 2017. METHODS An internet literature search was performed using Google Scholar and other sources to assist in the writing of this narrative review and account. CONCLUSIONS In parallel to the development of the new Biomedical Beamline ID17 at the European Synchrotron Radiation Facility in Grenoble in the late nineties, Elke focused her interest and her personal and professional priorities on MRT, particularly on its clinical goals. She outlined her main objectives in several documents: (1) develop a new paradigm of cancer care by broadening the foundation for MRT. (2) Filling the gaps in basic biological knowledge about the mechanisms of MRT effects on normal and neoplastic tissues. (3) Broaden the preclinical level of evidence for the low normal organ toxicity of MRT versus standard X-ray irradiations; preclinical experiments involved the application of MRT to animal tumor patients, to animals of larger size than laboratory rodents, using larger radiation field sizes, and irradiating in a real-time scenario comparable to the one planned for human patients. (4) To foster the specific purpose of radiosurgical MRT of tumor patients at the ESRF that required development of new, specific state of the art modalities and tools for treatment planning, dosimetry, dose calculation, patient positioning and, of particular importance, redundant levels of patient safety. Just as she was about to take responsibility as principal investigator for a prestigious international European project on a new radiation therapy, death called Elke in.
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Affiliation(s)
- Jean A Laissue
- Institute of Pathology, University of Bern, Bern, Switzerland
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6
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Pellicioli P, Donzelli M, Davis JA, Estève F, Hugtenburg R, Guatelli S, Petasecca M, Lerch MLF, Bräuer-Krisch E, Krisch M. Study of the X-ray radiation interaction with a multislit collimator for the creation of microbeams in radiation therapy. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:392-403. [PMID: 33650550 DOI: 10.1107/s1600577520016811] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 12/31/2020] [Indexed: 06/12/2023]
Abstract
Microbeam radiation therapy (MRT) is a developing radiotherapy, based on the use of beams only a few tens of micrometres wide, generated by synchrotron X-ray sources. The spatial fractionation of the homogeneous beam into an array of microbeams is possible using a multislit collimator (MSC), i.e. a machined metal block with regular apertures. Dosimetry in MRT is challenging and previous works still show differences between calculated and experimental dose profiles of 10-30%, which are not acceptable for a clinical implementation of treatment. The interaction of the X-rays with the MSC may contribute to the observed discrepancies; the present study therefore investigates the dose contribution due to radiation interaction with the MSC inner walls and radiation leakage of the MSC. Dose distributions inside a water-equivalent phantom were evaluated for different field sizes and three typical spectra used for MRT studies at the European Synchrotron Biomedical beamline ID17. Film dosimetry was utilized to determine the contribution of radiation interaction with the MSC inner walls; Monte Carlo simulations were implemented to calculate the radiation leakage contribution. Both factors turned out to be relevant for the dose deposition, especially for small fields. Photons interacting with the MSC walls may bring up to 16% more dose in the valley regions, between the microbeams. Depending on the chosen spectrum, the radiation leakage close to the phantom surface can contribute up to 50% of the valley dose for a 5 mm × 5 mm field. The current study underlines that a detailed characterization of the MSC must be performed systematically and accurate MRT dosimetry protocols must include the contribution of radiation leakage and radiation interaction with the MSC in order to avoid significant errors in the dose evaluation at the micrometric scale.
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Affiliation(s)
- P Pellicioli
- ID17 Biomedical Beamline, ESRF - The European Synchrotron, 71 avenue des Martyrs, Grenoble, France
| | - M Donzelli
- ID17 Biomedical Beamline, ESRF - The European Synchrotron, 71 avenue des Martyrs, Grenoble, France
| | - J A Davis
- School of Physics, University of Wollongong, Wollongong, Australia
| | - F Estève
- STROBE - Synchrotron Radiation for Biomedicine, Grenoble, France
| | - R Hugtenburg
- Swansea University Medical School, Singleton Park, Swansea, United Kingdom
| | - S Guatelli
- School of Physics, University of Wollongong, Wollongong, Australia
| | - M Petasecca
- School of Physics, University of Wollongong, Wollongong, Australia
| | - M L F Lerch
- School of Physics, University of Wollongong, Wollongong, Australia
| | - E Bräuer-Krisch
- ID17 Biomedical Beamline, ESRF - The European Synchrotron, 71 avenue des Martyrs, Grenoble, France
| | - M Krisch
- ID17 Biomedical Beamline, ESRF - The European Synchrotron, 71 avenue des Martyrs, Grenoble, France
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7
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Schültke E, Fiedler S, Menk RH, Jaekel F, Dreossi D, Casarin K, Tromba G, Bartzsch S, Kriesen S, Hildebrandt G, Arfelli F. Perspectives for microbeam irradiation at the SYRMEP beamline. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:410-418. [PMID: 33650552 PMCID: PMC7941286 DOI: 10.1107/s1600577521000400] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/12/2021] [Indexed: 05/10/2023]
Abstract
It has been shown previously both in vitro and in vivo that microbeam irradiation (MBI) can control malignant tumour cells more effectively than the clinically established concepts of broad beam irradiation. With the aim to extend the international capacity for microbeam research, the first MBI experiment at the biomedical beamline SYRMEP of the Italian synchrotron facility ELETTRA has been conducted. Using a multislit collimator produced by the company TECOMET, arrays of quasi-parallel microbeams were successfully generated with a beam width of 50 µm and a centre-to-centre distance of 400 µm. Murine melanoma cell cultures were irradiated with a target dose of approximately 65 Gy at a mean photon energy of ∼30 keV with a dose rate of 70 Gy s-1 and a peak-to-valley dose of ∼123. This work demonstrated a melanoma cell reduction of approximately 80% after MBI. It is suggested that, while a high energy is essential to achieve high dose rates in order to deposit high treatment doses in a short time in a deep-seated target, for in vitro studies and for the treatment of superficial tumours a spectrum in the lower energy range might be equally suitable or even advantageous.
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Affiliation(s)
- Elisabeth Schültke
- Department of Radiooncology, Rostock University Medical Center, Südring 75, 18059 Rostock, Germany
| | - Stefan Fiedler
- European Molecular Biology Laboratory, Notkestrasse 85, 22607 Hamburg, Germany
| | - Ralf Hendrik Menk
- Elettra-Sincrotrone Trieste, Strada Statale 14, Trieste 34149, Italy
- University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- Trieste Section, Istituto Nazionale Fisica Nucleare (INFN), Trieste, Italy
| | - Felix Jaekel
- Department of Radiooncology, Rostock University Medical Center, Südring 75, 18059 Rostock, Germany
| | - Diego Dreossi
- Elettra-Sincrotrone Trieste, Strada Statale 14, Trieste 34149, Italy
| | - Katia Casarin
- Elettra-Sincrotrone Trieste, Strada Statale 14, Trieste 34149, Italy
| | - Giuliana Tromba
- Elettra-Sincrotrone Trieste, Strada Statale 14, Trieste 34149, Italy
| | - Stefan Bartzsch
- Department of Radiooncology, Technical University Munich, Munich, Germany
- Institute for Innovative Radiotherapy, Helmholtz-Zentrum Munich (HMGU), Munich, Germany
| | - Stephan Kriesen
- Department of Radiooncology, Rostock University Medical Center, Südring 75, 18059 Rostock, Germany
| | - Guido Hildebrandt
- Department of Radiooncology, Rostock University Medical Center, Südring 75, 18059 Rostock, Germany
| | - Fulvia Arfelli
- Trieste Section, Istituto Nazionale Fisica Nucleare (INFN), Trieste, Italy
- Department of Physics, University of Trieste, Trieste, Italy
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8
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A Monte Carlo intercomparison of peak-to-valley dose ratios and output factors for microbeam radiation therapy. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108980] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Day LRJ, Pellicioli P, Gagliardi F, Barnes M, Smyth LML, Butler D, Livingstone J, Stevenson AW, Lye J, Poole CM, Hausermann D, Rogers PAW, Crosbie JC. A Monte Carlo model of synchrotron radiotherapy shows good agreement with experimental dosimetry measurements: Data from the imaging and medical beamline at the Australian Synchrotron. Phys Med 2020; 77:64-74. [PMID: 32791426 DOI: 10.1016/j.ejmp.2020.07.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 06/22/2020] [Accepted: 07/13/2020] [Indexed: 02/06/2023] Open
Abstract
Experimental measurement of Synchrotron Radiotherapy (SyncRT) doses is challenging, especially for Microbeam Radiotherapy (MRT), which is characterised by very high dynamic ranges with spatial resolutions on the micrometer scale. Monte Carlo (MC) simulation is considered a gold standard for accurate dose calculation in radiotherapy, and is therefore routinely relied upon to produce verification data. We present a MC model for Australian Synchrotron's Imaging and Medical Beamline (IMBL), which is capable of generating accurate dosimetry data to inform and/or verify SyncRT experiments. Our MC model showed excellent agreement with dosimetric measurement for Synchrotron Broadbeam Radiotherapy (SBBR). Our MC model is also the first to achieve validation for MRT, using two methods of dosimetry, to within clinical tolerances of 5% for a 20×20 mm2 field size, except for surface measurements at 5 mm depth, which remained to within good agreement of 7.5%. Our experimental methodology has allowed us to control measurement uncertainties for MRT doses to within 5-6%, which has also not been previously achieved, and provides a confidence which until now has been lacking in MRT validation studies. The MC model is suitable for SyncRT dose calculation of clinically relevant field sizes at the IMBL, and can be extended to include medical beamlines at other Synchrotron facilities as well. The presented MC model will be used as a validation tool for treatment planning dose calculation algorithms, and is an important step towards veterinary SyncRT trials at the Australian Synchrotron.
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Affiliation(s)
- L R J Day
- School of Science, RMIT University, Melbourne, Australia.
| | - P Pellicioli
- The European Synchrotron Radiation Facility, ID17 Biomedical Beamline, Grenoble, France; Inserm UA7 STROBE, Grenoble Alps University, Grenoble, France; Swansea University Medical School, Singleton Park, Swansea, United Kingdom
| | - F Gagliardi
- Radiation Oncology, Alfred Hospital, Melbourne, Australia; School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
| | - M Barnes
- Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia; Australian Nuclear Science and Technology Organisation (ANSTO), Australian Synchrotron, Clayton, Australia
| | - L M L Smyth
- Department of Obstetrics and Gynaecology, University of Melbourne, Royal Women's Hospital, Melbourne, Australia
| | - D Butler
- Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), Melbourne, Australia
| | - J Livingstone
- Australian Nuclear Science and Technology Organisation (ANSTO), Australian Synchrotron, Clayton, Australia
| | - A W Stevenson
- Australian Nuclear Science and Technology Organisation (ANSTO), Australian Synchrotron, Clayton, Australia
| | - J Lye
- Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), Melbourne, Australia
| | - C M Poole
- Radiation Analytics, Brisbane, Australia
| | - D Hausermann
- Australian Nuclear Science and Technology Organisation (ANSTO), Australian Synchrotron, Clayton, Australia
| | - P A W Rogers
- Department of Obstetrics and Gynaecology, University of Melbourne, Royal Women's Hospital, Melbourne, Australia
| | - J C Crosbie
- School of Science, RMIT University, Melbourne, Australia
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10
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Bartzsch S, Corde S, Crosbie JC, Day L, Donzelli M, Krisch M, Lerch M, Pellicioli P, Smyth LML, Tehei M. Technical advances in x-ray microbeam radiation therapy. Phys Med Biol 2020; 65:02TR01. [PMID: 31694009 DOI: 10.1088/1361-6560/ab5507] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In the last 25 years microbeam radiation therapy (MRT) has emerged as a promising alternative to conventional radiation therapy at large, third generation synchrotrons. In MRT, a multi-slit collimator modulates a kilovoltage x-ray beam on a micrometer scale, creating peak dose areas with unconventionally high doses of several hundred Grays separated by low dose valley regions, where the dose remains well below the tissue tolerance level. Pre-clinical evidence demonstrates that such beam geometries lead to substantially reduced damage to normal tissue at equal tumour control rates and hence drastically increase the therapeutic window. Although the mechanisms behind MRT are still to be elucidated, previous studies indicate that immune response, tumour microenvironment, and the microvasculature may play a crucial role. Beyond tumour therapy, MRT has also been suggested as a microsurgical tool in neurological disorders and as a primer for drug delivery. The physical properties of MRT demand innovative medical physics and engineering solutions for safe treatment delivery. This article reviews technical developments in MRT and discusses existing solutions for dosimetric validation, reliable treatment planning and safety. Instrumentation at synchrotron facilities, including beam production, collimators and patient positioning systems, is also discussed. Specific solutions reviewed in this article include: dosimetry techniques that can cope with high spatial resolution, low photon energies and extremely high dose rates of up to 15 000 Gy s-1, dose calculation algorithms-apart from pure Monte Carlo Simulations-to overcome the challenge of small voxel sizes and a wide dynamic dose-range, and the use of dose-enhancing nanoparticles to combat the limited penetrability of a kilovoltage energy spectrum. Finally, concepts for alternative compact microbeam sources are presented, such as inverse Compton scattering set-ups and carbon nanotube x-ray tubes, that may facilitate the transfer of MRT into a hospital-based clinical environment. Intensive research in recent years has resulted in practical solutions to most of the technical challenges in MRT. Treatment planning, dosimetry and patient safety systems at synchrotrons have matured to a point that first veterinary and clinical studies in MRT are within reach. Should these studies confirm the promising results of pre-clinical studies, the authors are confident that MRT will become an effective new radiotherapy option for certain patients.
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Affiliation(s)
- Stefan Bartzsch
- Department of Radiation Oncology, School of Medicine, Technical University of Munich, Klinikum rechts der Isar, Munich, Germany. Helmholtz Centre Munich, Institute for Radiation Medicine, Munich, Germany
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11
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Dipuglia A, Cameron M, Davis JA, Cornelius IM, Stevenson AW, Rosenfeld AB, Petasecca M, Corde S, Guatelli S, Lerch MLF. Validation of a Monte Carlo simulation for Microbeam Radiation Therapy on the Imaging and Medical Beamline at the Australian Synchrotron. Sci Rep 2019; 9:17696. [PMID: 31776395 PMCID: PMC6881291 DOI: 10.1038/s41598-019-53991-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 11/05/2019] [Indexed: 01/05/2023] Open
Abstract
Microbeam Radiation Therapy (MRT) is an emerging cancer treatment modality characterised by the use of high-intensity synchrotron-generated x-rays, spatially fractionated by a multi-slit collimator (MSC), to ablate target tumours. The implementation of an accurate treatment planning system, coupled with simulation tools that allow for independent verification of calculated dose distributions are required to ensure optimal treatment outcomes via reliable dose delivery. In this article we present data from the first Geant4 Monte Carlo radiation transport model of the Imaging and Medical Beamline at the Australian Synchrotron. We have developed the model for use as an independent verification tool for experiments in one of three MRT delivery rooms and therefore compare simulation results with equivalent experimental data. The normalised x-ray spectra produced by the Geant4 model and a previously validated analytical model, SPEC, showed very good agreement using wiggler magnetic field strengths of 2 and 3 T. However, the validity of absolute photon flux at the plane of the Phase Space File (PSF) for a fixed number of simulated electrons was unable to be established. This work shows a possible limitation of the G4SynchrotronRadiation process to model synchrotron radiation when using a variable magnetic field. To account for this limitation, experimentally derived normalisation factors for each wiggler field strength determined under reference conditions were implemented. Experimentally measured broadbeam and microbeam dose distributions within a Gammex RMI457 Solid Water® phantom were compared to simulated distributions generated by the Geant4 model. Simulated and measured broadbeam dose distributions agreed within 3% for all investigated configurations and measured depths. Agreement between the simulated and measured microbeam dose distributions agreed within 5% for all investigated configurations and measured depths.
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Affiliation(s)
- Andrew Dipuglia
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Matthew Cameron
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Jeremy A Davis
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Iwan M Cornelius
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Andrew W Stevenson
- CSIRO, Clayton, 3168, Australia
- Imaging and Medical Beamline, ANSTO/Australian Synchrotron, Melbourne, 3168, Australia
| | - Anatoly B Rosenfeld
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Marco Petasecca
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Stéphanie Corde
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
- Department of Radiation Oncology, Prince of Wales Hospital, Randwick, 2031, Australia
| | - Susanna Guatelli
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia
| | - Michael L F Lerch
- Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, 2522, Australia.
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12
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First experimental measurement of the effect of cardio‐synchronous brain motion on the dose distribution during microbeam radiation therapy. Med Phys 2019; 47:213-222. [DOI: 10.1002/mp.13899] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 09/16/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023] Open
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13
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Donzelli M, Bräuer-Krisch E, Oelfke U, Wilkens JJ, Bartzsch S. Hybrid dose calculation: a dose calculation algorithm for microbeam radiation therapy. Phys Med Biol 2018; 63:045013. [PMID: 29324439 PMCID: PMC5964549 DOI: 10.1088/1361-6560/aaa705] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/07/2017] [Accepted: 01/11/2018] [Indexed: 12/17/2022]
Abstract
Microbeam radiation therapy (MRT) is still a preclinical approach in radiation oncology that uses planar micrometre wide beamlets with extremely high peak doses, separated by a few hundred micrometre wide low dose regions. Abundant preclinical evidence demonstrates that MRT spares normal tissue more effectively than conventional radiation therapy, at equivalent tumour control. In order to launch first clinical trials, accurate and efficient dose calculation methods are an inevitable prerequisite. In this work a hybrid dose calculation approach is presented that is based on a combination of Monte Carlo and kernel based dose calculation. In various examples the performance of the algorithm is compared to purely Monte Carlo and purely kernel based dose calculations. The accuracy of the developed algorithm is comparable to conventional pure Monte Carlo calculations. In particular for inhomogeneous materials the hybrid dose calculation algorithm out-performs purely convolution based dose calculation approaches. It is demonstrated that the hybrid algorithm can efficiently calculate even complicated pencil beam and cross firing beam geometries. The required calculation times are substantially lower than for pure Monte Carlo calculations.
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Affiliation(s)
- Mattia Donzelli
- The European
Synchrotron Radiation Facility, 71 Avenue des Martyrs 38000,
Grenoble, France
- The Institute of
Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG,
United Kingdom
- Author to whom any correspondence should be
addressed
| | - Elke Bräuer-Krisch
- The European
Synchrotron Radiation Facility, 71 Avenue des Martyrs 38000,
Grenoble, France
| | - Uwe Oelfke
- The Institute of
Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG,
United Kingdom
| | - Jan J Wilkens
- Department of Radiation Oncology, Klinikum rechts
der Isar, Technical University of
Munich, Ismaninger Straße 22, 81675 Munich,
Germany
| | - Stefan Bartzsch
- The Institute of
Cancer Research, 15 Cotswold Road, Sutton, London SM2 5NG,
United Kingdom
- Department of Radiation Oncology, Klinikum rechts
der Isar, Technical University of
Munich, Ismaninger Straße 22, 81675 Munich,
Germany
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14
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Gagliardi FM, Day L, Poole CM, Franich RD, Geso M. Water equivalent PRESAGE®
for synchrotron radiation therapy dosimetry. Med Phys 2018; 45:1255-1265. [DOI: 10.1002/mp.12745] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 11/17/2017] [Accepted: 12/16/2017] [Indexed: 11/12/2022] Open
Affiliation(s)
- Frank M. Gagliardi
- Alfred Health Radiation Oncology; The Alfred; Melbourne Vic 3004 Australia
- School of Health and Biomedical Sciences; RMIT University; Bundoora Vic 3083 Australia
| | - Liam Day
- School of Science; RMIT University; Melbourne Vic 3000 Australia
| | | | - Rick D. Franich
- School of Science; RMIT University; Melbourne Vic 3000 Australia
| | - Moshi Geso
- School of Health and Biomedical Sciences; RMIT University; Bundoora Vic 3083 Australia
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15
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Lin H, Jing J, Xu L, Mao X. Monte Carlo study of the influence of energy spectra, mesh size, high Z element on dose and PVDR based on 1-D and 3-D heterogeneous mouse head phantom for Microbeam Radiation Therapy. Phys Med 2017; 44:96-107. [DOI: 10.1016/j.ejmp.2017.07.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/05/2017] [Accepted: 07/07/2017] [Indexed: 12/01/2022] Open
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16
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Schültke E, Balosso J, Breslin T, Cavaletti G, Djonov V, Esteve F, Grotzer M, Hildebrandt G, Valdman A, Laissue J. Microbeam radiation therapy - grid therapy and beyond: a clinical perspective. Br J Radiol 2017; 90:20170073. [PMID: 28749174 PMCID: PMC5853350 DOI: 10.1259/bjr.20170073] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Microbeam irradiation is spatially fractionated radiation on a micrometer scale. Microbeam irradiation with therapeutic intent has become known as microbeam radiation therapy (MRT). The basic concept of MRT was developed in the 1980s, but it has not yet been tested in any human clinical trial, even though there is now a large number of animal studies demonstrating its marked therapeutic potential with an exceptional normal tissue sparing effect. Furthermore, MRT is conceptually similar to macroscopic grid based radiation therapy which has been used in clinical practice for decades. In this review, the potential clinical applications of MRT are analysed for both malignant and non-malignant diseases.
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Affiliation(s)
- Elisabeth Schültke
- 1 Department of Radiooncology, Rostock University Medical Center, Rostock, Germany
| | - Jacques Balosso
- 2 Departement of Radiation Oncology and Medical Physics, University Grenoble Alpes (UGA) and Centre Hospitalier Universitaire Grenoble Alpes (CHUGA), Grenoble, France
| | - Thomas Breslin
- 3 Department of Oncology, Clinical Sciences, Lund University, Lund, Sweden.,4 Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Guido Cavaletti
- 5 Experimental Neurology Unit and Milan Center for Neuroscience, School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
| | - Valentin Djonov
- 6 Institute of Anatomy, University of Bern, Bern, Switzerland
| | - Francois Esteve
- 2 Departement of Radiation Oncology and Medical Physics, University Grenoble Alpes (UGA) and Centre Hospitalier Universitaire Grenoble Alpes (CHUGA), Grenoble, France
| | - Michael Grotzer
- 7 Department of Oncology, University Children's Hospital of Zurich, Zurich, Switzerland
| | - Guido Hildebrandt
- 1 Department of Radiooncology, Rostock University Medical Center, Rostock, Germany
| | - Alexander Valdman
- 8 Department of Oncology and Pathology, Karolinska University Hospital, Stockholm, Sweden
| | - Jean Laissue
- 6 Institute of Anatomy, University of Bern, Bern, Switzerland
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17
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Cameron M, Cornelius I, Cutajar D, Davis J, Rosenfeld A, Lerch M, Guatelli S. Comparison of phantom materials for use in quality assurance of microbeam radiation therapy. JOURNAL OF SYNCHROTRON RADIATION 2017; 24:866-876. [PMID: 28664894 DOI: 10.1107/s1600577517005641] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 04/13/2017] [Indexed: 06/07/2023]
Abstract
Microbeam radiation therapy (MRT) is a promising radiotherapy modality that uses arrays of spatially fractionated micrometre-sized beams of synchrotron radiation to irradiate tumours. Routine dosimetry quality assurance (QA) prior to treatment is necessary to identify any changes in beam condition from the treatment plan, and is undertaken using solid homogeneous phantoms. Solid phantoms are designed for, and routinely used in, megavoltage X-ray beam radiation therapy. These solid phantoms are not necessarily designed to be water-equivalent at low X-ray energies, and therefore may not be suitable for MRT QA. This work quantitatively determines the most appropriate solid phantom to use in dosimetric MRT QA. Simulated dose profiles of various phantom materials were compared with those calculated in water under the same conditions. The phantoms under consideration were RMI457 Solid Water (Gammex-RMI, Middleton, WI, USA), Plastic Water (CIRS, Norfolk, VA, USA), Plastic Water DT (CIRS, Norfolk, VA, USA), PAGAT (CIRS, Norfolk, VA, USA), RW3 Solid Phantom (PTW Freiburg, Freiburg, Germany), PMMA, Virtual Water (Med-Cal, Verona, WI, USA) and Perspex. RMI457 Solid Water and Virtual Water were found to be the best approximations for water in MRT dosimetry (within ±3% deviation in peak and 6% in valley). RW3 and Plastic Water DT approximate the relative dose distribution in water (within ±3% deviation in the peak and 5% in the valley). PAGAT, PMMA, Perspex and Plastic Water are not recommended to be used as phantoms for MRT QA, due to dosimetric discrepancies greater than 5%.
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Affiliation(s)
- Matthew Cameron
- CMRP, University of Wollongong, Wollongong, NSW 2522, Australia
| | | | - Dean Cutajar
- CMRP, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Jeremy Davis
- CMRP, University of Wollongong, Wollongong, NSW 2522, Australia
| | | | - Michael Lerch
- CMRP, University of Wollongong, Wollongong, NSW 2522, Australia
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18
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Poole CM, Day LRJ, Rogers PAW, Crosbie JC. Synchrotron microbeam radiotherapy in a commercially available treatment planning system. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa5f1a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Stevenson AW, Crosbie JC, Hall CJ, Häusermann D, Livingstone J, Lye JE. Quantitative characterization of the X-ray beam at the Australian Synchrotron Imaging and Medical Beamline (IMBL). JOURNAL OF SYNCHROTRON RADIATION 2017; 24:110-141. [PMID: 28009552 DOI: 10.1107/s1600577516015563] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/04/2016] [Indexed: 06/06/2023]
Abstract
A critical early phase for any synchrotron beamline involves detailed testing, characterization and commissioning; this is especially true of a beamline as ambitious and complex as the Imaging & Medical Beamline (IMBL) at the Australian Synchrotron. IMBL staff and expert users have been performing precise experiments aimed at quantitative characterization of the primary polychromatic and monochromatic X-ray beams, with particular emphasis placed on the wiggler insertion devices (IDs), the primary-slit system and any in vacuo and ex vacuo filters. The findings from these studies will be described herein. These results will benefit IMBL and other users in the future, especially those for whom detailed knowledge of the X-ray beam spectrum (or `quality') and flux density is important. This information is critical for radiotherapy and radiobiology users, who ultimately need to know (to better than 5%) what X-ray dose or dose rate is being delivered to their samples. Various correction factors associated with ionization-chamber (IC) dosimetry have been accounted for, e.g. ion recombination, electron-loss effects. A new and innovative approach has been developed in this regard, which can provide confirmation of key parameter values such as the magnetic field in the wiggler and the effective thickness of key filters. IMBL commenced operation in December 2008 with an Advanced Photon Source (APS) wiggler as the (interim) ID. A superconducting multi-pole wiggler was installed and operational in January 2013. Results are obtained for both of these IDs and useful comparisons are made. A comprehensive model of the IMBL has been developed, embodied in a new computer program named spec.exe, which has been validated against a variety of experimental measurements. Having demonstrated the reliability and robustness of the model, it is then possible to use it in a practical and predictive manner. It is hoped that spec.exe will prove to be a useful resource for synchrotron science in general, and for hard X-ray beamlines, whether they are based on bending magnets or insertion devices, in particular. In due course, it is planned to make spec.exe freely available to other synchrotron scientists.
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Affiliation(s)
- Andrew W Stevenson
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Jeffrey C Crosbie
- School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
| | - Christopher J Hall
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Daniel Häusermann
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Jayde Livingstone
- Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Jessica E Lye
- School of Science, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
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20
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Fournier P, Cornelius I, Donzelli M, Requardt H, Nemoz C, Petasecca M, Bräuer-Krisch E, Rosenfeld A, Lerch M. X-Tream quality assurance in synchrotron X-ray microbeam radiation therapy. JOURNAL OF SYNCHROTRON RADIATION 2016; 23:1180-1190. [PMID: 27577773 DOI: 10.1107/s1600577516009322] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/08/2016] [Indexed: 06/06/2023]
Abstract
Microbeam radiation therapy (MRT) is a novel irradiation technique for brain tumours treatment currently under development at the European Synchrotron Radiation Facility in Grenoble, France. The technique is based on the spatial fractionation of a highly brilliant synchrotron X-ray beam into an array of microbeams using a multi-slit collimator (MSC). After promising pre-clinical results, veterinary trials have recently commenced requiring the need for dedicated quality assurance (QA) procedures. The quality of MRT treatment demands reproducible and precise spatial fractionation of the incoming synchrotron beam. The intensity profile of the microbeams must also be quickly and quantitatively characterized prior to each treatment for comparison with that used for input to the dose-planning calculations. The Centre for Medical Radiation Physics (University of Wollongong, Australia) has developed an X-ray treatment monitoring system (X-Tream) which incorporates a high-spatial-resolution silicon strip detector (SSD) specifically designed for MRT. In-air measurements of the horizontal profile of the intrinsic microbeam X-ray field in order to determine the relative intensity of each microbeam are presented, and the alignment of the MSC is also assessed. The results show that the SSD is able to resolve individual microbeams which therefore provides invaluable QA of the horizontal field size and microbeam number and shape. They also demonstrate that the SSD used in the X-Tream system is very sensitive to any small misalignment of the MSC. In order to allow as rapid QA as possible, a fast alignment procedure of the SSD based on X-ray imaging with a low-intensity low-energy beam has been developed and is presented in this publication.
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Affiliation(s)
- Pauline Fournier
- Centre for Medical Radiation Physics, University of Wollongong, Australia
| | - Iwan Cornelius
- Centre for Medical Radiation Physics, University of Wollongong, Australia
| | | | | | | | - Marco Petasecca
- Centre for Medical Radiation Physics, University of Wollongong, Australia
| | | | - Anatoly Rosenfeld
- Centre for Medical Radiation Physics, University of Wollongong, Australia
| | - Michael Lerch
- Centre for Medical Radiation Physics, University of Wollongong, Australia
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21
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Lye JE, Harty PD, Butler DJ, Crosbie JC, Livingstone J, Poole CM, Ramanathan G, Wright T, Stevenson AW. Absolute dosimetry on a dynamically scanned sample for synchrotron radiotherapy using graphite calorimetry and ionization chambers. Phys Med Biol 2016; 61:4201-22. [DOI: 10.1088/0031-9155/61/11/4201] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Gagliardi FM, Cornelius I, Blencowe A, Franich RD, Geso M. High resolution 3D imaging of synchrotron generated microbeams. Med Phys 2015; 42:6973-86. [DOI: 10.1118/1.4935410] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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23
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Crosbie JC, Fournier P, Bartzsch S, Donzelli M, Cornelius I, Stevenson AW, Requardt H, Bräuer-Krisch E. Energy spectra considerations for synchrotron radiotherapy trials on the ID17 bio-medical beamline at the European Synchrotron Radiation Facility. JOURNAL OF SYNCHROTRON RADIATION 2015; 22:1035-1041. [PMID: 26134808 DOI: 10.1107/s1600577515008115] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/23/2015] [Indexed: 06/04/2023]
Abstract
The aim of this study was to validate the kilovoltage X-ray energy spectrum on the ID17 beamline at the European Synchrotron Radiation Facility (ESRF). The purpose of such validation was to provide an accurate energy spectrum as the input to a computerized treatment planning system, which will be used in synchrotron microbeam radiotherapy trials at the ESRF. Calculated and measured energy spectra on ID17 have been reported previously but recent additions and safety modifications to the beamline for veterinary trials warranted a fresh investigation. The authors used an established methodology to compare X-ray attenuation measurements in copper sheets (referred to as half value layer measurements in the radiotherapy field) with the predictions of a theoretical model. A cylindrical ionization chamber in air was used to record the relative attenuation of the X-ray beam intensity by increasing thicknesses of high-purity copper sheets. The authors measured the half value layers in copper for two beamline configurations, which corresponded to differing spectral conditions. The authors obtained good agreement between the measured and predicted half value layers for the two beamline configurations. The measured first half value layer was 1.754 ± 0.035 mm Cu and 1.962 ± 0.039 mm Cu for the two spectral conditions, compared with theoretical predictions of 1.763 ± 0.039 mm Cu and 1.984 ± 0.044 mm Cu, respectively. The calculated mean energies for the two conditions were 105 keV and 110 keV and there was not a substantial difference in the calculated percentage depth dose curves in water between the different spectral conditions. The authors observed a difference between their calculated energy spectra and the spectra previously reported by other authors, particularly at energies greater than 100 keV. The validation of the beam spectrum by the copper half value layer measurements means the authors can provide an accurate spectrum as an input to a treatment planning system for the forthcoming veterinary trials of microbeam radiotherapy to spontaneous tumours in cats and dogs.
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Affiliation(s)
- Jeffrey C Crosbie
- School of Applied Sciences, RMIT University, Melbourne, Victoria, Australia
| | - Pauline Fournier
- Centre for Medical Radiation Physics, University of Wollongong, New South Wales, Australia
| | | | | | - Iwan Cornelius
- Centre for Medical Radiation Physics, University of Wollongong, New South Wales, Australia
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