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Johnson RP. Meeting the detector challenges for pre-clinical proton and ion computed tomography. Phys Med Biol 2024; 69:11TR02. [PMID: 38657632 DOI: 10.1088/1361-6560/ad42fc] [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: 09/21/2023] [Accepted: 04/24/2024] [Indexed: 04/26/2024]
Abstract
Six decades after its conception, proton computed tomography (pCT) and proton radiography have yet to be used in medical clinics. However, good progress has been made on relevant detector technologies in the past two decades, and a few prototype pCT systems now exist that approach the performance needed for a clinical device. The tracking and energy-measurement technologies in common use are described, as are the few pCT scanners that are in routine operation at this time. Most of these devices still look like detector R&D efforts as opposed to medical devices, are difficult to use, are at least a factor of five slower than desired for clinical use, and are too small to image many parts of the human body. Recommendations are made for what to consider when engineering a pre-clinical pCT scanner that is designed to meet clinical needs in terms of performance, cost, and ease of use.
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Affiliation(s)
- Robert P Johnson
- Physics Department, University of California at Santa Cruz, Santa Cruz, CA 95064, United States of America
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2
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Lundberg M, Meijers A, Souris K, Deffet S, Weber DC, Lomax A, Knopf A. Technical note: development of a simulation framework, enabling the investigation of locally tuned single energy proton radiography. Biomed Phys Eng Express 2024; 10:027002. [PMID: 38241732 DOI: 10.1088/2057-1976/ad20a8] [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: 09/27/2023] [Accepted: 01/19/2024] [Indexed: 01/21/2024]
Abstract
Range uncertainties remain a limitation for the confined dose distribution that proton therapy can offer. The uncertainty stems from the ambiguity when translating CT Hounsfield Units (HU) into proton stopping powers. Proton Radiography (PR) can be used to verify the proton range. Specifically, PR can be used as a quality-control tool for CBCT-based synthetic CTs. An essential part of the work illustrating the potential of PR has been conducted using multi-layer ionization chamber (MLIC) detectors and mono-energetic PR. Due to the dimensions of commercially available MLICs, clinical adoption is cumbersome. Here, we present a simulation framework exploring locally-tuned single energy (LTSE) proton radiography and corresponding potential compact PR detector designs. Based on a planning CT data set, the presented framework models the water equivalent thickness. Subsequently, it analyses the proton energies required to pass through the geometry within a defined ROI. In the final step, an LTSE PR is simulated using the MCsquare Monte Carlo code. In an anatomical head phantom, we illustrate that LTSE PR allows for a significantly shorter longitudinal dimension of MLICs. We compared PR simulations for two exemplary 30 × 30 mm2proton fields passing the phantom at a 90° angle at an anterior and a posterior location in an iso-centric setup. The longitudinal distance over which all spots per field range out is significantly reduced for LTSE PR compared to mono-energetic PR. In addition, we illustrate the difference in shape of integral depth dose (IDD) when using constrained PR energies. Finally, we demonstrate the accordance of simulated and experimentally acquired IDDs for an LTSE PR acquisition. As the next steps, the framework will be used to investigate the sensitivity of LTSE PR to various sources of errors. Furthermore, we will use the framework to systematically explore the dimensions of an optimized MLIC design for daily clinical use.
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Affiliation(s)
- Måns Lundberg
- Institute for Medical Engineering and Medical Informatics, School of Life Science FHNW, Muttenz, Switzerland
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
| | - Arturs Meijers
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
| | - Kevin Souris
- Ion Beam Applications SA, Louvain-La-Neuve, Belgium
| | | | - Damien C Weber
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
- Department of Radiation Oncology, University Hospital of Zürich, Zürich, Switzerland
- Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Antony Lomax
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
- Department of Physics, ETH Zurich, Zurich, Switzerland
| | - Antje Knopf
- Institute for Medical Engineering and Medical Informatics, School of Life Science FHNW, Muttenz, Switzerland
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3
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Darne CD, Robertson DG, Alsanea F, Collins-Fekete CA, Beddar S. A novel proton-integrating radiography system design using a monolithic scintillator detector: experimental studies. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2022; 1027:166077. [PMID: 35221402 PMCID: PMC8872121 DOI: 10.1016/j.nima.2021.166077] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Research on proton-based imaging systems aims to improve treatment planning, internal anatomy visualization, and patient alignment for proton radiotherapy. The purpose of this study was to demonstrate a new proton radiography system design consisting of a monolithic plastic scintillator volume and two optical cameras for use with scanning proton pencil beams. Unlike the thin scintillating plates currently used for proton radiography, the plastic scintillator volume (20 × 20 × 20 cm3) captures a wider distribution of proton beam energy depositions and avoids proton-beam modulation. The proton imaging system's characteristics were tested using image uniformity (2.6% over a 5 × 5 cm2 area), stability (0.37%), and linearity (R2 = 1) studies. We used the light distribution produced within the plastic scintillator to generate proton radiographs via two different approaches: (a) integrating light by using a camera placed along the beam axis, and (b) capturing changes to the proton Bragg peak positions with a camera placed perpendicularly to the beam axis. The latter method was used to plot and evaluate relative shifts in percentage depth light (PDL) profiles of proton beams with and without a phantom in the beam path. A curvelet minimization algorithm used differences in PDL profiles to reconstruct and refine the phantom water-equivalent thickness (WET) map. Gammex phantoms were used to compare the proton radiographs generated by these two methods. The relative accuracies in calculating WET of the phantoms using the calibration-based beam-integration (and the PDL) methods were -0.18 ± 0.35% (-0.29 ± 3.11%), -0.11 ± 0.51% (-0.15 ± 2.64%), -2.94 ± 1.20% (-0.75 ± 6.11%), and -1.65 ± 0.35% (0.36 ± 3.93%) for solid water, adipose, cortical bone, and PMMA, respectively. Further exploration of this unique multicamera-based imaging system is warranted and could lead to clinical applications that improve treatment planning and patient alignment for proton radiotherapy.
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Affiliation(s)
- Chinmay D Darne
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Daniel G Robertson
- Division of Medical Physics, Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, AZ 85054, USA
| | - Fahed Alsanea
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Sam Beddar
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Dedes G, Dickmann J, Giacometti V, Rit S, Krah N, Meyer S, Bashkirov V, Schulte R, Johnson RP, Parodi K, Landry G. The role of Monte Carlo simulation in understanding the performance of proton computed tomography. Z Med Phys 2022; 32:23-38. [PMID: 32798033 PMCID: PMC9948882 DOI: 10.1016/j.zemedi.2020.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 05/18/2020] [Accepted: 06/16/2020] [Indexed: 01/28/2023]
Abstract
Proton computed tomography (pCT) is a promising tomographic imaging modality allowing direct reconstruction of proton relative stopping power (RSP) required for proton therapy dose calculation. In this review article, we aim at highlighting the role of Monte Carlo (MC) simulation in pCT studies. After describing the requirements for performing proton computed tomography and the various pCT scanners actively used in recent research projects, we present an overview of available MC simulation platforms. The use of MC simulations in the scope of investigations of image reconstruction, and for the evaluation of optimal RSP accuracy, precision and spatial resolution omitting detector effects is then described. In the final sections of the review article, we present specific applications of realistic MC simulations of an existing pCT scanner prototype, which we describe in detail.
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Affiliation(s)
- George Dedes
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany.
| | - Jannis Dickmann
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany
| | - Valentina Giacometti
- The Patrick G Johnston Centre for Cancer Research, Queen's University of Belfast, Northern Ireland Cancer Centre, Belfast, Northern Ireland, United Kingdom
| | - Simon Rit
- University of Lyon, CREATIS, CNRS UMR5220; Inserm U1044, INSA-Lyon, Université Lyon 1, Centre Léon Bérard, Lyon, France
| | - Nils Krah
- University of Lyon, CREATIS, CNRS UMR5220; Inserm U1044, INSA-Lyon, Université Lyon 1, Centre Léon Bérard, Lyon, France; University of Lyon, Institute of Nuclear Physics Lyon (IPNL), CNRS UMR 5822, Villeurbanne, France
| | - Sebastian Meyer
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany; Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Vladimir Bashkirov
- Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, CA, United States of America
| | - Reinhard Schulte
- Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, CA, United States of America
| | - Robert P Johnson
- Department of Physics, U. C. Santa Cruz, Santa Cruz, CA, United States of America
| | - Katia Parodi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany
| | - Guillaume Landry
- Department of Radiation Oncology, Department of Medical Physics, University Hospital, LMU Munich, Munich, Germany; German Cancer Consortium, (DKTK), Munich, Germany; Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany
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5
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DeJongh DF, DeJongh EA, Rykalin V, DeFillippo G, Pankuch M, Best AW, Coutrakon G, Duffin KL, Karonis NT, Ordoñez CE, Sarosiek C, Schulte RW, Winans JR, Block AM, Hentz CL, Welsh JS. A comparison of proton stopping power measured with proton CT and x-ray CT in fresh postmortem porcine structures. Med Phys 2021; 48:7998-8009. [PMID: 34739140 PMCID: PMC8678357 DOI: 10.1002/mp.15334] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/05/2021] [Accepted: 10/22/2021] [Indexed: 12/31/2022] Open
Abstract
PURPOSE Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield units of patient tissues into proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly measuring proton stopping power. We aim to demonstrate proton CT imaging with complex porcine samples, to analyze in detail three-dimensional regions of interest, and to compare proton stopping powers directly measured by proton CT to those determined from x-ray CT scans. METHODS We have used a prototype proton imaging system with single proton tracking to acquire proton radiography and proton CT images of a sample of porcine pectoral girdle and ribs, and a pig's head. We also acquired close in time x-ray CT scans of the same samples and compared proton stopping power measurements from the two modalities. In the case of the pig's head, we obtained x-ray CT scans from two different scanners and compared results from high-dose and low-dose settings. RESULTS Comparing our reconstructed proton CT images with images derived from x-ray CT scans, we find agreement within 1% to 2% for soft tissues and discrepancies of up to 6% for compact bone. We also observed large discrepancies, up to 40%, for cavitated regions with mixed content of air, soft tissue, and bone, such as sinus cavities or tympanic bullae. CONCLUSIONS Our images and findings from a clinically realistic proton CT scanner demonstrate the potential for proton CT to be used for low-dose treatment planning with reduced margins.
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Affiliation(s)
| | | | | | - Greg DeFillippo
- Northwestern Medicine Chicago Proton Center, Warrenville, Illinois, USA
| | - Mark Pankuch
- Northwestern Medicine Chicago Proton Center, Warrenville, Illinois, USA
| | - Andrew W Best
- Department of Physics, Northern Illinois University, DeKalb, Illinois, USA
| | - George Coutrakon
- Department of Physics, Northern Illinois University, DeKalb, Illinois, USA
| | - Kirk L Duffin
- Department of Computer Science, Northern Illinois University, DeKalb, Illinois, USA
| | - Nicholas T Karonis
- Department of Computer Science, Northern Illinois University, DeKalb, Illinois, USA
- Argonne National Laboratory, Data Science and Learning Division, Argonne, Illinois, USA
| | - Caesar E Ordoñez
- Department of Computer Science, Northern Illinois University, DeKalb, Illinois, USA
| | - Christina Sarosiek
- Department of Physics, Northern Illinois University, DeKalb, Illinois, USA
| | | | - John R Winans
- Department of Computer Science, Northern Illinois University, DeKalb, Illinois, USA
| | - Alec M Block
- Edward Hines Jr. VA Medical Center, Radiation Oncology Service, Hines, Illinois, USA
- Department of Radiation Oncology, Loyola University Stritch School of Medicine, Maywood, Illinois, USA
| | - Courtney L Hentz
- Edward Hines Jr. VA Medical Center, Radiation Oncology Service, Hines, Illinois, USA
- Department of Radiation Oncology, Loyola University Stritch School of Medicine, Maywood, Illinois, USA
| | - James S Welsh
- Edward Hines Jr. VA Medical Center, Radiation Oncology Service, Hines, Illinois, USA
- Department of Radiation Oncology, Loyola University Stritch School of Medicine, Maywood, Illinois, USA
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6
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Pettersen HES, Aehle M, Alme J, Barnaföldi GG, Borshchov V, van den Brink A, Chaar M, Eikeland V, Feofilov G, Garth C, Gauger NR, Genov G, Grøttvik O, Helstrup H, Igolkin S, Keidel R, Kobdaj C, Kortus T, Leonhardt V, Mehendale S, Mulawade RN, Odland OH, Papp G, Peitzmann T, Piersimoni P, Protsenko M, Rehman AU, Richter M, Santana J, Schilling A, Seco J, Songmoolnak A, Sølie JR, Tambave G, Tymchuk I, Ullaland K, Varga-Kofarago M, Volz L, Wagner B, Wendzel S, Wiebel A, Xiao R, Yang S, Yokoyama H, Zillien S, Röhrich D. Investigating particle track topology for range telescopes in particle radiography using convolutional neural networks. Acta Oncol 2021; 60:1413-1418. [PMID: 34259117 DOI: 10.1080/0284186x.2021.1949037] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Proton computed tomography (pCT) and radiography (pRad) are proposed modalities for improved treatment plan accuracy and in situ treatment validation in proton therapy. The pCT system of the Bergen pCT collaboration is able to handle very high particle intensities by means of track reconstruction. However, incorrectly reconstructed and secondary tracks degrade the image quality. We have investigated whether a convolutional neural network (CNN)-based filter is able to improve the image quality. MATERIAL AND METHODS The CNN was trained by simulation and reconstruction of tens of millions of proton and helium tracks. The CNN filter was then compared to simple energy loss threshold methods using the Area Under the Receiver Operating Characteristics curve (AUROC), and by comparing the image quality and Water Equivalent Path Length (WEPL) error of proton and helium radiographs filtered with the same methods. RESULTS The CNN method led to a considerable improvement of the AUROC, from 74.3% to 97.5% with protons and from 94.2% to 99.5% with helium. The CNN filtering reduced the WEPL error in the helium radiograph from 1.03 mm to 0.93 mm while no improvement was seen in the CNN filtered pRads. CONCLUSION The CNN improved the filtering of proton and helium tracks. Only in the helium radiograph did this lead to improved image quality.
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Affiliation(s)
| | - Max Aehle
- Chair for Scientific Computing, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Johan Alme
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | | | | | | | - Mamdouh Chaar
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Viljar Eikeland
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Grigory Feofilov
- Department of High Energy and Elementary Particles Physics, St. Petersburg University, St. Petersburg, Russia
| | - Christoph Garth
- Scientific Visualization Lab, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Nicolas R. Gauger
- Chair for Scientific Computing, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Georgi Genov
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Ola Grøttvik
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Håvard Helstrup
- Department of Computer Science, Electrical Engineering and Mathematical Sciences, Western Norway University of Applied Sciences, Bergen, Norway
| | - Sergey Igolkin
- Department of High Energy and Elementary Particles Physics, St. Petersburg University, St. Petersburg, Russia
| | - Ralf Keidel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Chinorat Kobdaj
- Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Tobias Kortus
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Viktor Leonhardt
- Scientific Visualization Lab, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Shruti Mehendale
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Raju Ningappa Mulawade
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Odd Harald Odland
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Gábor Papp
- Institute for Physics, Eötvös Loránd University, Budapest, Hungary
| | - Thomas Peitzmann
- Institute for Subatomic Physics, Utrecht University/Nikhef, Utrecht, Netherlands
| | | | - Maksym Protsenko
- Research and Production Enterprise “LTU” (RPE LTU), Kharkiv, Ukraine
| | - Attiq Ur Rehman
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | | | - Joshua Santana
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Alexander Schilling
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Joao Seco
- Department of Biomedical Physics in Radiation Oncology, DKFZ-German Cancer Research Center, Heidelberg, Germany
- Department of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
| | - Arnon Songmoolnak
- Department of Physics and Technology, University of Bergen, Bergen, Norway
- Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Jarle Rambo Sølie
- Department of Diagnostic Physics, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Ganesh Tambave
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Ihor Tymchuk
- Research and Production Enterprise “LTU” (RPE LTU), Kharkiv, Ukraine
| | - Kjetil Ullaland
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | | | - Lennart Volz
- Department of Biophysics, GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt, Germany
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Boris Wagner
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Steffen Wendzel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Alexander Wiebel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - RenZheng Xiao
- Department of Physics and Technology, University of Bergen, Bergen, Norway
- College of Mechanical & Power Engineering, China Three Gorges University, Yichang, People’s Republic of China
| | - Shiming Yang
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Hiroki Yokoyama
- Institute for Subatomic Physics, Utrecht University/Nikhef, Utrecht, Netherlands
| | - Sebastian Zillien
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Dieter Röhrich
- Department of Physics and Technology, University of Bergen, Bergen, Norway
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Tanaka S, Miyamoto N, Matsuo Y, Yoshimura T, Takao S, Matsuura T. First experimental results of gated proton imaging using x-ray fluoroscopy to detect a fiducial marker. Phys Med Biol 2021; 66. [PMID: 34433146 DOI: 10.1088/1361-6560/ac212b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 08/25/2021] [Indexed: 11/12/2022]
Abstract
Increasing numbers of proton imaging research studies are being conducted for accurate proton range determination in proton therapy treatment planning. However, there is no proton imaging system that deals with motion artifacts. In this study, a gated proton imaging system was developed and the first experimental results of proton radiography (pRG) were obtained for a moving object without motion artifacts. A motion management system using dual x-ray fluoroscopy for detecting a spherical gold fiducial marker was introduced and the proton beam was gated in accordance with the motion of the object. To demonstrate the performance of the gated proton imaging system, gated pRG images of a moving phantom were acquired experimentally, and the motion artifacts clearly were diminished. Also, the factors causing image deteriorations were evaluated focusing on the new gating system developed here, and the main factor was identified as the latency (with a maximum value of 93 ms) between the ideal gating signal according to the actual marker position and the actual gating signal. The possible deterioration due to the latency of the proton imaging system and proton beam irradiation was small owing to appropriate setting of the time structure.
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Affiliation(s)
- Sodai Tanaka
- Institute for Quantum Medical Science, Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology, Chiba, Chiba, 263-8555, Japan
| | - Naoki Miyamoto
- Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan
| | - Yuto Matsuo
- Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo, Hokkaido, 060-8648, Japan
| | - Takaaki Yoshimura
- Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido 060-0812, Japan
| | - Seishin Takao
- Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan
| | - Taeko Matsuura
- Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan
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8
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van der Heyden B, Cohilis M, Souris K, de Freitas Nascimento L, Sterpin E. Artificial intelligence supported single detector multi-energy proton radiography system. Phys Med Biol 2021; 66. [PMID: 33621962 DOI: 10.1088/1361-6560/abe918] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 02/23/2021] [Indexed: 12/12/2022]
Abstract
Proton radiography imaging was proposed as a promising technique to evaluate internal anatomical changes, to enable pre-treatment patient alignment, and most importantly, to optimize the patient specific CT number to stopping-power ratio conversion. The clinical implementation rate of proton radiography systems is still limited due to their complex bulky design, together with the persistent problem of (in)elastic nuclear interactions and multiple Coulomb scattering (i.e. range mixing). In this work, a compact multi-energy proton radiography system was proposed in combination with an artificial intelligence network architecture (ProtonDSE) to remove the persistent problem of proton scatter in proton radiography. A realistic Monte Carlo model of the Proteus®One accelerator was built at 200 and 220 MeV to isolate the scattered proton signal in 236 proton radiographies of 80 digital anthropomorphic phantoms. ProtonDSE was trained to predict the proton scatter distribution at two beam energies in a 60%/25%/15% scheme for training, testing, and validation. A calibration procedure was proposed to derive the water equivalent thickness image based on the detector dose response relationship at both beam energies. ProtonDSE network performance was evaluated with quantitative metrics that showed an overall mean absolute percentage error below 1.4% ± 0.4% in our test dataset. For one example patient, detector dose to WET conversions were performed based on the total dose (ITotal), the primary proton dose (IPrimary), and the ProtonDSE corrected detector dose (ICorrected). The determined WET accuracy was compared with respect to the reference WET by idealistic raytracing in a manually delineated region-of-interest inside the brain. The error was determined 4.3% ± 4.1% forWET(ITotal),2.2% ± 1.4% forWET(IPrimary),and 2.5% ± 2.0% forWET(ICorrected).
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Affiliation(s)
- Brent van der Heyden
- KU Leuven, Department of Oncology, Laboratory of Experimental Radiotherapy, Leuven, Belgium
| | - Marie Cohilis
- UCLouvain, Institut de recherche expérimentale et clinique, Molecular Imaging Radiotherapy and Oncology Lab, Brussels, Belgium
| | - Kevin Souris
- UCLouvain, Institut de recherche expérimentale et clinique, Molecular Imaging Radiotherapy and Oncology Lab, Brussels, Belgium
| | | | - Edmond Sterpin
- KU Leuven, Department of Oncology, Laboratory of Experimental Radiotherapy, Leuven, Belgium.,UCLouvain, Institut de recherche expérimentale et clinique, Molecular Imaging Radiotherapy and Oncology Lab, Brussels, Belgium
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9
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Farace P, Tommasino F, Righetto R, Fracchiolla F, Scaringella M, Bruzzi M, Civinini C. Technical Note: CT calibration for proton treatment planning by cross-calibration with proton CT data. Med Phys 2021; 48:1349-1355. [PMID: 33382083 DOI: 10.1002/mp.14698] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 11/30/2020] [Accepted: 12/23/2020] [Indexed: 12/31/2022] Open
Abstract
PURPOSE This study explores the possibility of a new method for x-ray computed tomography (CT) calibration by means of cross-calibration with proton CT (pCT) data. The proposed method aims at a more accurate conversion of CT Hounsfield Units (HU) into proton stopping power ratio (SPR) relative to water to be used in proton-therapy treatment planning. METHODS X-ray CT scan was acquired on a synthetic anthropomorphic phantom, composed of different tissue equivalent materials (TEMs). A pCT apparatus was instead adopted to obtain a reference three-dimensional distribution of the phantom's SPR values. After rigid registration, the x-ray CT was artificially blurred to the same resolution of pCT. Then a scatter plot showing voxel-by-voxel SPR values as a function of HU was employed to link the two measurements and thus obtaining a cross-calibrated x-ray CT calibration curve. The cross-calibration was tested at treatment planning system and then compared with a conventional calibration based on exactly the same TEMs constituting the anthropomorphic phantom. RESULTS Cross-calibration provided an accurate SPR mapping, better than by conventional TEMs calibration. The dose distribution of single beams optimized on the reference SPR map was recomputed on cross-calibrated CT, showing, with respect to conventional calibration, minor deviation at the dose fall-off (lower than 1%). CONCLUSIONS The presented data demonstrated that, by means of reference pCT data, a heterogeneous phantom can be used for CT calibration, paving the way to the use of biological samples, with their accurate description of patients' tissues. This overcomes the limitations of conventional CT calibration requiring homogenous samples, only available by synthetic TEMs, which fail in accurately mimicking the properties of biological tissues. Once a heterogeneous biological sample is provided with its corresponding reference SPR maps, a cross-calibration procedure could be adopted by other PT centers, even when not equipped with a pCT system.
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Affiliation(s)
- Paolo Farace
- Protontherapy Unit, Hospital of Trento, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy.,Istituto Nazionale di Fisica Nucleare TIFPA, via Sommarive, 14, Trento, Italy
| | - Francesco Tommasino
- Istituto Nazionale di Fisica Nucleare TIFPA, via Sommarive, 14, Trento, Italy.,Department of Physics, University of Trento, via Sommarive, 14, Trento, Italy
| | - Roberto Righetto
- Protontherapy Unit, Hospital of Trento, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy.,Istituto Nazionale di Fisica Nucleare TIFPA, via Sommarive, 14, Trento, Italy
| | - Francesco Fracchiolla
- Protontherapy Unit, Hospital of Trento, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy.,Istituto Nazionale di Fisica Nucleare TIFPA, via Sommarive, 14, Trento, Italy
| | - Monica Scaringella
- Istituto Nazionale di Fisica Nucleare sezione di Firenze, Via G. Sansone 1, Sesto Fiorentino, Italy
| | - Mara Bruzzi
- Istituto Nazionale di Fisica Nucleare sezione di Firenze, Via G. Sansone 1, Sesto Fiorentino, Italy.,Dipartimento di Fisica e Astronomia, Università degli Studi di Firenze, via G. Sansone 1, Sesto Fiorentino, Italy
| | - Carlo Civinini
- Istituto Nazionale di Fisica Nucleare sezione di Firenze, Via G. Sansone 1, Sesto Fiorentino, Italy
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10
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Meijers A, Seller Oria C, Free J, Langendijk JA, Knopf AC, Both S. Technical Note: First report on an in vivo range probing quality control procedure for scanned proton beam therapy in head and neck cancer patients. Med Phys 2021; 48:1372-1380. [PMID: 33428795 DOI: 10.1002/mp.14713] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/23/2020] [Accepted: 01/05/2021] [Indexed: 01/07/2023] Open
Abstract
PURPOSE The capability of proton therapy to provide highly conformal dose distributions is impaired by range uncertainties. The aim of this work is to apply range probing (RP), a form of a proton radiography-based quality control (QC) procedure for range accuracy assessment in head and neck cancer (HNC) patients in a clinical setting. METHODS AND MATERIALS This study included seven HNC patients. RP acquisition was performed using a multi-layer ionization chamber (MLIC). Per patient, two RP frames were acquired within the first two weeks of treatment, on days when a repeated CT scan was obtained. Per RP frame, integral depth dose (IDD) curves of 81 spots around the treatment isocenter were acquired. Range errors are determined as a discrepancy between calculated IDDs in the treatment planning system and measured residual ranges by the MLIC. Range errors are presented relative to the water equivalent path length of individual proton spots. In addition to reporting results for complete measurement frames, an analysis, excluding range error contributions due to anatomical changes, is presented. RESULTS Discrepancies between measured and calculated ranges are smaller when performing RP calculations on the day-specific patient anatomy rather than the planning CT. The patient-specific range evaluation shows an agreement between calculated and measured ranges for spots in anatomically consistent areas within 3% (1.5 standard deviation). CONCLUSIONS The results of an RP-based QC procedure implemented in the clinical practice for HNC patients have been demonstrated. The agreement of measured and simulated proton ranges confirms the 3% uncertainty margin for robust optimization. Anatomical variations show a predominant effect on range accuracy, motivating efforts towards the implementation of adaptive radiotherapy.
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Affiliation(s)
- Arturs Meijers
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Carmen Seller Oria
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Jeffrey Free
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Antje C Knopf
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Division for Medical Radiation Physics, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Stefan Both
- Department of Radiation Oncology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
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11
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DeJongh EA, DeJongh DF, Polnyi I, Rykalin V, Sarosiek C, Coutrakon G, Duffin KL, Karonis NT, Ordoñez CE, Pankuch M, Winans JR, Welsh JS. Technical Note: A fast and monolithic prototype clinical proton radiography system optimized for pencil beam scanning. Med Phys 2021; 48:1356-1364. [PMID: 33382453 DOI: 10.1002/mp.14700] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/12/2020] [Accepted: 12/21/2020] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To demonstrate a proton-imaging system based on well-established fast scintillator technology to achieve high performance with low cost and complexity, with the potential of a straightforward translation into clinical use. METHODS The system tracks individual protons through one (X, Y) scintillating fiber tracker plane upstream and downstream of the object and into a 13-cm -thick scintillating block residual energy detector. The fibers in the tracker planes are multiplexed into silicon photomultipliers (SiPMs) to reduce the number of electronics channels. The light signal from the residual energy detector is collected by 16 photomultiplier tubes (PMTs). Only four signals from the PMTs are output from each event, which allows for fast signal readout. A robust calibration method of the PMT signal to residual energy has been developed to obtain accurate proton images. The development of patient-specific scan patterns using multiple input energies allows for an image to be produced with minimal excess dose delivered to the patient. RESULTS The calibration of signals in the energy detector produces accurate residual range measurements limited by intrinsic range straggling. We measured the water-equivalent thickness (WET) of a block of solid water (physical thickness of 6.10 mm) with a proton radiograph. The mean WET from all pixels in the block was 6.13 cm (SD 0.02 cm). The use of patient-specific scan patterns using multiple input energies enables imaging with a compact range detector. CONCLUSIONS We have developed a prototype clinical proton radiography system for pretreatment imaging in proton radiation therapy. We have optimized the system for use with pencil beam scanning systems and have achieved a reduction of size and complexity compared to previous designs.
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Affiliation(s)
| | | | | | | | - Christina Sarosiek
- Department of Physics, Northern Illinois University, DeKalb, IL, 60115, USA
| | - George Coutrakon
- Department of Physics, Northern Illinois University, DeKalb, IL, 60115, USA
| | - Kirk L Duffin
- Department of Computer Science, Northern Illinois University, DeKalb, IL, 60115, USA
| | - Nicholas T Karonis
- Department of Computer Science, Northern Illinois University, DeKalb, IL, 60115, USA.,Data Science and Learning Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Caesar E Ordoñez
- Department of Computer Science, Northern Illinois University, DeKalb, IL, 60115, USA
| | - Mark Pankuch
- Northwestern Medicine Chicago Proton Center, Warrenville, IL, 60555, USA
| | - John R Winans
- Department of Computer Science, Northern Illinois University, DeKalb, IL, 60115, USA
| | - James S Welsh
- Radiation Oncology Service, Edward Hines Jr VA Medical Center, Hines, IL, 60141, USA.,Department of Radiation Oncology, Loyola University Stritch School of Medicine, Maywood, IL, 60153, USA
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12
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Pettersen HES, Volz L, Sølie JR, Alme J, Barnaföldi GG, Barthel R, van den Brink A, Borshchov V, Chaar M, Eikeland V, Genov G, Grøttvik O, Helstrup H, Keidel R, Kobdaj C, van der Kolk N, Mehendale S, Meric I, Harald Odland O, Papp G, Peitzmann T, Piersimoni P, Protsenko M, Ur Rehman A, Richter M, Tefre Samnøy A, Seco J, Shafiee H, Songmoolnak A, Tambave G, Tymchuk I, Ullaland K, Varga-Kofarago M, Wagner B, Xiao R, Yang S, Yokoyama H, Röhrich D. Helium radiography with a digital tracking calorimeter-a Monte Carlo study for secondary track rejection. Phys Med Biol 2021; 66:035004. [PMID: 33181502 DOI: 10.1088/1361-6560/abca03] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Radiation therapy using protons and heavier ions is a fast-growing therapeutic option for cancer patients. A clinical system for particle imaging in particle therapy would enable online patient position verification, estimation of the dose deposition through range monitoring and a reduction of uncertainties in the calculation of the relative stopping power of the patient. Several prototype imaging modalities offer radiography and computed tomography using protons and heavy ions. A Digital Tracking Calorimeter (DTC), currently under development, has been proposed as one such detector. In the DTC 43 longitudinal layers of laterally stacked ALPIDE CMOS monolithic active pixel sensor chips are able to reconstruct a large number of simultaneously recorded proton tracks. In this study, we explored the capability of the DTC for helium imaging which offers favorable spatial resolution over proton imaging. Helium ions exhibit a larger cross section for inelastic nuclear interactions, increasing the number of produced secondaries in the imaged object and in the detector itself. To that end, a filtering process able to remove a large fraction of the secondaries was identified, and the track reconstruction process was adapted for helium ions. By filtering on the energy loss along the tracks, on the incoming angle and on the particle ranges, 97.5% of the secondaries were removed. After passing through 16 cm water, 50.0% of the primary helium ions survived; after the proposed filtering 42.4% of the primaries remained; finally after subsequent image reconstruction 31% of the primaries remained. Helium track reconstruction leads to more track matching errors compared to protons due to the increased available focus strength of the helium beam. In a head phantom radiograph, the Water Equivalent Path Length error envelope was 1.0 mm for helium and 1.1 mm for protons. This accuracy is expected to be sufficient for helium imaging for pre-treatment verification purposes.
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13
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Gianoli C, Göppel M, Meyer S, Palaniappan P, Rädler M, Kamp F, Belka C, Riboldi M, Parodi K. Patient-specific CT calibration based on ion radiography for different detector configurations in 1H, 4He and 12C ion pencil beam scanning. Phys Med Biol 2020; 65:245014. [PMID: 32629442 DOI: 10.1088/1361-6560/aba319] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The empirical conversion of the treatment planning x-ray computed tomography (CT) image to ion stopping power relative to water causes dose calculation inaccuracies in ion beam therapy. A patient-specific calibration of the CT image is enabled by the combination of an ion radiography (iRad) with the forward-projection of the empirically converted CT image along the estimated ion trajectories. This work investigated the patient-specific CT calibration for list-mode and integration-mode detector configurations, with reference to a ground truth ion CT (iCT) image. Analytical simulations of idealized carbon ion and proton trajectories in a numerical anthropomorphic phantom and realistic Monte Carlo simulations of proton, helium and carbon ion pencil beam scanning in a clinical CT image of a head-and-neck patient were considered. Controlled inaccuracy and noise levels were applied to the calibration curve and to the iRad, respectively. The impact of the selection of slices and angles of the iRads, as well as the choice of the optimization algorithm, were investigated. Accurate and robust CT calibration was obtained in analytical simulations of straight carbon ion trajectories. Analytical simulations of non-straight proton trajectories due to scattering suggested limitations for integration-mode but not for list-mode. To make the most of integration-mode, a dedicated objective function was proposed, demonstrating the desired accuracy for sufficiently high proton statistics in analytical simulations. In clinical data the inconsistencies between the iRad and the forward-projection of the ground truth iCT image were in the same order of magnitude as the applied inaccuracies (up to 5%). The accuracy of the CT calibration were within 2%-5% for integration-mode and 1%-3% for list-mode. The feasibility of successful patient-specific CT calibration depends on detector technologies and is primarily limited by these above mentioned inconsistencies that slightly penalize protons over helium and carbon ions due to larger scattering and beam spot size.
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Affiliation(s)
- Chiara Gianoli
- Department of Medical Physics - Experimental Physics, Ludwig-Maximilians-Universität München, Munich, Germany. Author to whom any correspondence should be addressed
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14
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Deffet S, Cohilis M, Souris K, Salvo K, Depuydt T, Sterpin E, Macq B. openPR - A computational tool for CT conversion assessment with proton radiography. Med Phys 2020; 48:387-396. [PMID: 33125725 DOI: 10.1002/mp.14571] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/20/2020] [Accepted: 10/15/2020] [Indexed: 12/21/2022] Open
Abstract
PURPOSE One of the main sources of uncertainty in proton therapy is the conversion of the Hounsfield Units of the planning CT to (relative) proton stopping powers. Proton radiography provides range error maps but these can be affected by other sources of errors as well as the CT conversion (e.g., residual misalignment). To better understand and quantify range uncertainty, it is desirable to measure the individual contributions and particularly those associated to the CT conversion. METHODS A workflow is proposed to carry out an assessment of the CT conversion solely on the basis of proton radiographs of real tissues measured with a multilayer ionization chamber (MLIC). The workflow consists of a series of four stages: (a) CT and proton radiography acquisitions, (b) CT and proton radiography registration in postprocessing, (c) sample-specific validation of the semi-empirical model both used in the registration and to estimate the water equivalent path length (WEPL), and (d) WEPL error estimation. The workflow was applied to a pig head as part of the validation of the CT calibration of the proton therapy center PARTICLE at UZ Leuven, Belgium. RESULTS The CT conversion-related uncertainty computed based on the well-established safety margin rule of 1.2 mm + 2.4% were overestimated by 71% on the pig head. However, the range uncertainty was very much underestimated where cavities were encountered by the protons. Excluding areas with cavities, the overestimation of the uncertainty was 500%. A correlation was found between these localized errors and HUs between -1000 and -950, suggesting that the underestimation was not a consequence of an inaccurate conversion but was probably rather due to the resolution of the CT leading to material mixing at interfaces. To reduce these errors, the CT calibration curve was adapted by increasing the HU interval corresponding to the air up to -950. CONCLUSION The application of the workflow as part of the validation of the CT conversion to RSPs showed an overall overestimation of the expected uncertainty. Moreover, the largest WEPL errors were found to be related to the presence of cavities which nevertheless are associated with low WEPL values. This suggests that the use of this workflow on patients or in a generalized study on different types of animal tissues could shed sufficient light on how the contributions to the CT conversion-related uncertainty add up to potentially reduce up to several millimeters the uncertainty estimations taken into account in treatment planning. All the algorithms required to perform the workflow were implemented in the computational tool named openPR which is part of openREGGUI, an open-source image processing platform for adaptive proton therapy.
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Affiliation(s)
- Sylvain Deffet
- Institute of Information and Communication Technologies, Université catholique de Louvain, Louvain-La-Neuve, 1348, Belgium
| | - Marie Cohilis
- Center of Molecular Imaging, Radiotherapy and Oncology, Institut de Recherche Expérimentale et Clinique (IREC), Universitécatholique de Louvain, Louvain-La-Neuve, 1348, Belgium
| | - Kevin Souris
- Center of Molecular Imaging, Radiotherapy and Oncology, Institut de Recherche Expérimentale et Clinique (IREC), Universitécatholique de Louvain, Louvain-La-Neuve, 1348, Belgium
| | - Koen Salvo
- Department of Oncology, Katholieke Universiteit Leuven, Leuven, 3000, Belgium
| | - Tom Depuydt
- Department of Oncology, Katholieke Universiteit Leuven, Leuven, 3000, Belgium.,Department of Radiation Oncology, University Hospitals Leuven, Leuven, 3000, Belgium
| | - Edmond Sterpin
- Center of Molecular Imaging, Radiotherapy and Oncology, Institut de Recherche Expérimentale et Clinique (IREC), Universitécatholique de Louvain, Louvain-La-Neuve, 1348, Belgium.,Department of Oncology, Laboratory of Experimental Radiotherapy, Katholieke Universiteit Leuven, Leuven, 3000, Belgium
| | - Benoit Macq
- Institute of Information and Communication Technologies, Université catholique de Louvain, Louvain-La-Neuve, 1348, Belgium
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15
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Biston MC, Chiavassa S, Grégoire V, Thariat J, Lacornerie T. Time of PTV is ending, robust optimization comes next. Cancer Radiother 2020; 24:676-686. [PMID: 32861608 DOI: 10.1016/j.canrad.2020.06.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 12/25/2022]
Abstract
Continuous improvements have been made in the way to prescribe, record and report dose distributions since the therapeutic use of ionizing radiations. The international commission for radiation units and measurement (ICRU) has provided a common language for physicians and physicists to plan and evaluate their treatments. The PTV concept has been used for more than two decades but is becoming obsolete as the CTV-to-PTV margin creates a static dose cloud that does not properly recapitulate all planning vs. delivery uncertainties. The robust optimization concept has recently emerged to overcome the limitations of the PTV concept. This concept is integrated in the inverse planning process and minimizes deviations to planned dose distribution through integration of uncertainties in the planning objectives. It appears critical to account for the uncertainties that are specific to protons and should be accounted for to better exploit the clinical potential of proton therapy. It may also improve treatment quality particularly in hypofractionated photon plans of mobile tumors and more widely to photon radiotherapy. However, in contrast to the PTV concept, a posteriori evaluation of plan quality, called robust evaluation, using error-based scenarios is still warranted. Robust optimization metrics are warranted. These metrics are necessary to compare PTV-based photon and robustly optimized proton plans in general and in model-based NTCP approaches. Assessment of computational demand and approximations of robust optimization algorithms along with metrics to evaluate plan quality are needed but a step further to better prescribe radiotherapy may has been achieved.
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Affiliation(s)
- M-C Biston
- Department of Radiation Oncology, centre Léon-Bérard, 28, rue Laennec 69373 Lyon cedex 08, France; Creatis, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Villeurbanne, France.
| | - S Chiavassa
- Department of Medical Physics, Institut de cancérologie de l'Ouest, Saint-Herblain, France
| | - V Grégoire
- Department of Radiation Oncology, centre Léon-Bérard, 28, rue Laennec 69373 Lyon cedex 08, France
| | - J Thariat
- Department of radiation oncology, centre François-Baclesse/ARCHADE, Laboratoire de physique corpusculaire IN2P3/ENSICAEN-UMR6534, Unicaen, Normandie Universite, Caen, France
| | - T Lacornerie
- Department of Medical Physics, centre Oscar-Lambret, Lille, France
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16
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Rambo Sølie J, Volz L, Egil Seime Pettersen H, Piersimoni P, Harald Odland O, Röhrich D, Helstrup H, Peitzmann T, Ullaland K, Varga-Kofarago M, Mehendale S, Slettevoll Grøttvik O, Nilsen Eikeland V, Meric I, Seco J. Image quality of list-mode proton imaging without front trackers. ACTA ACUST UNITED AC 2020; 65:135012. [DOI: 10.1088/1361-6560/ab8ddb] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Parodi K. Latest developments in in-vivo imaging for proton therapy. Br J Radiol 2020; 93:20190787. [PMID: 31794249 PMCID: PMC7066959 DOI: 10.1259/bjr.20190787] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 11/18/2019] [Accepted: 11/28/2019] [Indexed: 12/11/2022] Open
Abstract
Owing to the favorable physical and biological properties of swift ions in matter, their application to radiation therapy for highly selective cancer treatment is rapidly spreading worldwide. To date, over 90 ion therapy facilities are operational, predominantly with proton beams, and about the same amount is under construction or planning.Over the last decades, considerable developments have been achieved in accelerator technology, beam delivery and medical physics to enhance conformation of the dose delivery to complex shaped tumor volumes, with excellent sparing of surrounding normal tissue and critical organs. Nevertheless, full clinical exploitation of the ion beam advantages is still challenged, especially by uncertainties in the knowledge of the beam range in the actual patient anatomy during the fractionated course of treatment, thus calling for continued multidisciplinary research in this rapidly emerging field.This contribution will review latest developments aiming to image the patient with the same beam quality as for therapy prior to treatment, and to visualize in-vivo the treatment delivery by exploiting irradiation-induced physical emissions, with different level of maturity from proof-of-concept studies in phantoms and first in-silico studies up to clinical testing and initial clinical evaluation.
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Affiliation(s)
- Katia Parodi
- Department of Experimental Physics – Medical Physics, Ludwig-Maximilians-Universität München, Faculty of Physics, Munich, Germany
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18
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Wohlfahrt P, Richter C. Status and innovations in pre-treatment CT imaging for proton therapy. Br J Radiol 2020; 93:20190590. [PMID: 31642709 PMCID: PMC7066941 DOI: 10.1259/bjr.20190590] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 10/04/2019] [Accepted: 10/21/2019] [Indexed: 12/19/2022] Open
Abstract
Pre-treatment CT imaging is a topic of growing importance in particle therapy. Improvements in the accuracy of stopping-power prediction are demanded to allow for a dose conformality that is not inferior to state-of-the-art image-guided photon therapy. Although range uncertainty has been kept practically constant over the last decades, recent technological and methodological developments, like the clinical application of dual-energy CT, have been introduced or arise at least on the horizon to improve the accuracy and precision of range prediction. This review gives an overview of the current status, summarizes the innovations in dual-energy CT and its potential impact on the field as well as potential alternative technologies for stopping-power prediction.
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Affiliation(s)
- Patrick Wohlfahrt
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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19
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Wohlfahrt P, Möhler C, Enghardt W, Krause M, Kunath D, Menkel S, Troost EGC, Greilich S, Richter C. Refinement of the Hounsfield look‐up table by retrospective application of patient‐specific direct proton stopping‐power prediction from dual‐energy CT. Med Phys 2020; 47:1796-1806. [DOI: 10.1002/mp.14085] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 02/03/2020] [Accepted: 02/05/2020] [Indexed: 12/26/2022] Open
Affiliation(s)
- Patrick Wohlfahrt
- OncoRay ‐ National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Helmholtz‐Zentrum Dresden‐Rossendorf Dresden Germany
- Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiooncology - OncoRay Dresden Germany
| | - Christian Möhler
- German Cancer Research Center (DKFZ) Heidelberg Germany
- National Center for Radiation Research in Oncology (NCRO) Heidelberg Institute for Radiation Oncology (HIRO) Heidelberg Germany
| | - Wolfgang Enghardt
- OncoRay ‐ National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Helmholtz‐Zentrum Dresden‐Rossendorf Dresden Germany
- Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiooncology - OncoRay Dresden Germany
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
- German Cancer Consortium (DKTK), Partner Site Dresden Germany
| | - Mechthild Krause
- OncoRay ‐ National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Helmholtz‐Zentrum Dresden‐Rossendorf Dresden Germany
- Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiooncology - OncoRay Dresden Germany
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
- German Cancer Consortium (DKTK), Partner Site Dresden Germany
- National Center for Tumor Diseases (NCT) Partner Site Dresden Dresden Germany
| | - Daniela Kunath
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
| | - Stefan Menkel
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
| | - Esther G. C. Troost
- OncoRay ‐ National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Helmholtz‐Zentrum Dresden‐Rossendorf Dresden Germany
- Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiooncology - OncoRay Dresden Germany
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
- German Cancer Consortium (DKTK), Partner Site Dresden Germany
- National Center for Tumor Diseases (NCT) Partner Site Dresden Dresden Germany
| | - Steffen Greilich
- German Cancer Research Center (DKFZ) Heidelberg Germany
- National Center for Radiation Research in Oncology (NCRO) Heidelberg Institute for Radiation Oncology (HIRO) Heidelberg Germany
| | - Christian Richter
- OncoRay ‐ National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Helmholtz‐Zentrum Dresden‐Rossendorf Dresden Germany
- Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiooncology - OncoRay Dresden Germany
- Department of Radiotherapy and Radiation Oncology Faculty of Medicine and University Hospital Carl Gustav Carus Technische Universität Dresden Dresden Germany
- German Cancer Consortium (DKTK), Partner Site Dresden Germany
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20
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Deffet S, Farace P, Macq B. Sparse deconvolution of proton radiography data to estimate water equivalent thickness maps. Med Phys 2019; 47:509-517. [DOI: 10.1002/mp.13917] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 09/30/2019] [Accepted: 11/04/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Sylvain Deffet
- Institute of Information and Communication Technologies Université catholique de Louvain Louvain‐La‐Neuve 1348Belgium
| | - Paolo Farace
- Proton Therapy Unit Hospital of Trento Trento 38100Italy
| | - Benoît Macq
- Institute of Information and Communication Technologies Université catholique de Louvain Louvain‐La‐Neuve 1348Belgium
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