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Shen CM, Lin YH, Li DF, Pan LK, Peng BR. Enhanced acrylic gauge with five eccentric circles for optimizing CT angiography spatial resolution via Taguchi's methodology. Technol Health Care 2024; 32:65-78. [PMID: 38669496 PMCID: PMC11191523 DOI: 10.3233/thc-248006] [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] [Indexed: 04/28/2024]
Abstract
BACKGROUND Cerebral examination via CTA is always the first choice for patients with unexpected brain injury or different types of brain lesions to detect ruptured hemangiomas, vascular infarcts, or other brain tissue lesions. OBJECTIVE This study innovated the acrylic gauge with five eccentric circles for computed tomography angiography (CTA) analysis to optimize the spatial resolution via Taguchi's methodology. METHODS The customized gauge was revised from the V-shaped slit gauge and transferred into five eccentric circles' slit gauge. The gauge was assembled with another six acrylic layers to simulate the human head. Taguchi's L18 orthogonal array was adopted to optimize the spatial resolution of CTA imaging quality. In doing so, six essential factors of CTA are kVp, mAs, spiral rotation pitch, FOV, rotation time of the CT and reconstruction filter, and each factor has either two or three levels to organize into eighteen combinations to simulate the full factor combination of 486 (21 × 35 = 486) times according to Taguchi's recommendation. Three well-trained radiologists ranked the gauge's 18 CTA scanned imaging qualities according to contrast, sharpness, and spatial resolution and derived the unique fish-bone-plot of six factors for further analysis. The optimal factor combination of CTA was proven by follow-up verification and ANOVA to obtain this study's dominant or minor factor. RESULTS The optimal factor combination of CTA was A2 (120 kVp), B3 (200 mAs), C1 (Pitch 0.6), D2 (FOV 220 mm2), E1 (rotation time 0.33 s), and F3 (Brain sharp, UC). Furthermore, deriving a quantified MDD (minimum detectable difference) to imply the spatial resolution of CTA, a semiauto profile analysis program run in MATLAB and OriginPro was recommended to evaluate the MDD and to suppress the manual error in calculation. Eventually, the derived MDDs of the conventional and optimal factor combinations of CTA were 2.35 and 2.26 mm, respectively, in this study. CONCLUSION Taguchi's methodology was found applicable for quantifying the CTA imaging quality in practical applications.
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Affiliation(s)
- Cheng-Mao Shen
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
- Department of Gastroenterology and Hepatology, Department of Internal Medicine, Taichung Armed Forces General Hospital, Taichung, Taiwan
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Ya-Hui Lin
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
- Department of Clinical Pharmacy Taichung Armed Forces General Hospital, Taichung, Taiwan
| | - Dian-Fong Li
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
- Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Lung-Kwang Pan
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
| | - Bing-Ru Peng
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
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2
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Aehle M, Alme J, Gábor Barnaföldi G, Blühdorn J, Bodova T, Borshchov V, van den Brink A, Eikeland V, Feofilov G, Garth C, Gauger NR, Grøttvik O, Helstrup H, Igolkin S, Keidel R, Kobdaj C, Kortus T, Kusch L, Leonhardt V, Mehendale S, Ningappa Mulawade R, Harald Odland O, O'Neill G, Papp G, Peitzmann T, Pettersen HES, Piersimoni P, Pochampalli R, Protsenko M, Rauch M, Ur Rehman A, Richter M, Röhrich D, Sagebaum M, Santana J, Schilling A, Seco J, Songmoolnak A, Sudár Á, Tambave G, Tymchuk I, Ullaland K, Varga-Kofarago M, Volz L, Wagner B, Wendzel S, Wiebel A, Xiao R, Yang S, Zillien S. Exploration of differentiability in a proton computed tomography simulation framework. Phys Med Biol 2023; 68:244002. [PMID: 37949060 DOI: 10.1088/1361-6560/ad0bdd] [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: 05/16/2023] [Accepted: 11/10/2023] [Indexed: 11/12/2023]
Abstract
Objective.Gradient-based optimization using algorithmic derivatives can be a useful technique to improve engineering designs with respect to a computer-implemented objective function. Likewise, uncertainty quantification through computer simulations can be carried out by means of derivatives of the computer simulation. However, the effectiveness of these techniques depends on how 'well-linearizable' the software is. In this study, we assess how promising derivative information of a typical proton computed tomography (pCT) scan computer simulation is for the aforementioned applications.Approach.This study is mainly based on numerical experiments, in which we repeatedly evaluate three representative computational steps with perturbed input values. We support our observations with a review of the algorithmic steps and arithmetic operations performed by the software, using debugging techniques.Main results.The model-based iterative reconstruction (MBIR) subprocedure (at the end of the software pipeline) and the Monte Carlo (MC) simulation (at the beginning) were piecewise differentiable. However, the observed high density and magnitude of jumps was likely to preclude most meaningful uses of the derivatives. Jumps in the MBIR function arose from the discrete computation of the set of voxels intersected by a proton path, and could be reduced in magnitude by a 'fuzzy voxels' approach. The investigated jumps in the MC function arose from local changes in the control flow that affected the amount of consumed random numbers. The tracking algorithm solves an inherently non-differentiable problem.Significance.Besides the technical challenges of merely applying AD to existing software projects, the MC and MBIR codes must be adapted to compute smoother functions. For the MBIR code, we presented one possible approach for this while for the MC code, this will be subject to further research. For the tracking subprocedure, further research on surrogate models is necessary.
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Affiliation(s)
- Max Aehle
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Johan Alme
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Johannes Blühdorn
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Tea Bodova
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | | | - Viljar Eikeland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Christoph Garth
- Scientific Visualization Lab, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Nicolas R Gauger
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Ola Grøttvik
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Håvard Helstrup
- Department of Computer Science, Electrical Engineering and Mathematical Sciences, Western Norway University of Applied Sciences, NO-5020 Bergen, Norway
| | | | - Ralf Keidel
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
- 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
| | - Lisa Kusch
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Viktor Leonhardt
- Scientific Visualization Lab, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Shruti Mehendale
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Raju Ningappa Mulawade
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
| | - Odd Harald Odland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
- Department of Oncology and Medical Physics, Haukeland University Hospital, NO-5021 Bergen, Norway
| | - George O'Neill
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Gábor Papp
- Institute for Physics, Eötvös Loránd University, 1/A Pázmány P. Sétány, H-1117 Budapest, Hungary
| | - Thomas Peitzmann
- Institute for Subatomic Physics, Utrecht University/Nikhef, Utrecht, Netherlands
| | | | - Pierluigi Piersimoni
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
- FSN Department, ENEA, Frascati Research Center, I-00044, Frascati, Italy
| | - Rohit Pochampalli
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Maksym Protsenko
- Research and Production Enterprise 'LTU' (RPE LTU), Kharkiv, Ukraine
| | - Max Rauch
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Attiq Ur Rehman
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Dieter Röhrich
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Max Sagebaum
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - 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, DKFZGerman Cancer Research Center, Heidelberg, Germany
- Department of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
| | - Arnon Songmoolnak
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
- Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Ákos Sudár
- Wigner Research Centre for Physics, Budapest, Hungary
| | - Ganesh Tambave
- Center for Medical and Radiation Physics (CMRP), National Institute of Science Education and Research (NISER), Bhubaneswar, India
| | - Ihor Tymchuk
- Research and Production Enterprise 'LTU' (RPE LTU), Kharkiv, Ukraine
| | - Kjetil Ullaland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Lennart Volz
- Biophysics, GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt, Germany
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Boris Wagner
- Department of Physics and Technology, University of Bergen, NO-5007 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, NO-5007 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, NO-5007 Bergen, Norway
| | - Sebastian Zillien
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, Worms, Germany
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Kortus T, Keidel R, Gauger NR. Towards Neural Charged Particle Tracking in Digital Tracking Calorimeters With Reinforcement Learning. IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 2023; 45:15820-15833. [PMID: 37581965 DOI: 10.1109/tpami.2023.3305027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
We propose a novel technique for reconstructing charged particles in digital tracking calorimeters using reinforcement learning aiming to benefit from the rapid progress and success of neural network architectures without the dependency on simulated or manually-labeled data. Here we optimize by trial-and-error a behavior policy acting as an approximation to the full combinatorial optimization problem, maximizing the physical plausibility of sampled trajectories. In modern processing pipelines used in high energy physics and related applications, tracking plays an essential role allowing to identify and follow charged particle trajectories traversing particle detectors. Due to the high multiplicity of charged particles and their physical interactions, randomly deflecting the particles, the reconstruction is a challenging undertaking, requiring fast, accurate and robust algorithms. Our approach works on graph-structured data, capturing track hypotheses through edge connections between particles in the detector layers. We demonstrate in a comprehensive study on simulated data for a particle detector used for proton computed tomography, the high potential as well as the competitiveness of our approach compared to a heuristic search algorithm and a model trained on ground truth. Finally, we point out limitations of our approach, guiding towards a robust foundation for further development of reinforcement learning based tracking.
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4
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Schilling A, Aehle M, Alme J, Barnaföldi GG, Bodova T, Borshchov V, van den Brink A, Eikeland V, Feofilov G, Garth C, Gauger NR, Grøttvik O, Helstrup H, Igolkin S, Keidel R, Kobdaj C, Kortus T, Leonhardt V, Mehendale S, Ningappa Mulawade R, Harald Odland O, O'Neill G, Papp G, Peitzmann T, Pettersen HES, Piersimoni P, Protsenko M, Rauch M, Ur Rehman A, Richter M, Röhrich D, Santana J, Seco J, Songmoolnak A, Sudár Á, Tambave G, Tymchuk I, Ullaland K, Varga-Kofarago M, Volz L, Wagner B, Wendzel S, Wiebel A, Xiao R, Yang S, Zillien S. Uncertainty-aware spot rejection rate as quality metric for proton therapy using a digital tracking calorimeter. Phys Med Biol 2023; 68:194001. [PMID: 37652034 DOI: 10.1088/1361-6560/acf5c2] [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: 05/25/2023] [Accepted: 08/31/2023] [Indexed: 09/02/2023]
Abstract
Objective.Proton therapy is highly sensitive to range uncertainties due to the nature of the dose deposition of charged particles. To ensure treatment quality, range verification methods can be used to verify that the individual spots in a pencil beam scanning treatment fraction match the treatment plan. This study introduces a novel metric for proton therapy quality control based on uncertainties in range verification of individual spots.Approach.We employ uncertainty-aware deep neural networks to predict the Bragg peak depth in an anthropomorphic phantom based on secondary charged particle detection in a silicon pixel telescope designed for proton computed tomography. The subsequently predicted Bragg peak positions, along with their uncertainties, are compared to the treatment plan, rejecting spots which are predicted to be outside the 95% confidence interval. The such-produced spot rejection rate presents a metric for the quality of the treatment fraction.Main results.The introduced spot rejection rate metric is shown to be well-defined for range predictors with well-calibrated uncertainties. Using this method, treatment errors in the form of lateral shifts can be detected down to 1 mm after around 1400 treated spots with spot intensities of 1 × 107protons. The range verification model used in this metric predicts the Bragg peak depth to a mean absolute error of 1.107 ± 0.015 mm.Significance.Uncertainty-aware machine learning has potential applications in proton therapy quality control. This work presents the foundation for future developments in this area.
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Affiliation(s)
- Alexander Schilling
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Max Aehle
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Johan Alme
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Tea Bodova
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | | | - Viljar Eikeland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Christoph Garth
- Scientific Visualization Lab, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Nicolas R Gauger
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Ola Grøttvik
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Håvard Helstrup
- Department of Computer Science, Electrical Engineering and Mathematical Sciences, Western Norway University of Applied Sciences, NO-5020 Bergen, Norway
| | | | - Ralf Keidel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
- Chair for Scientific Computing, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, 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, D-67549 Worms, Germany
| | - Viktor Leonhardt
- Scientific Visualization Lab, University of Kaiserslautern-Landau, D-67663 Kaiserslautern, Germany
| | - Shruti Mehendale
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Raju Ningappa Mulawade
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
| | - Odd Harald Odland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
- Department of Oncology and Medical Physics, Haukeland University Hospital, NO-5021 Bergen, Norway
| | - George O'Neill
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Gábor Papp
- Institute for Physics, Eötvös Loránd University, 1/A Pázmány P. Sétány, H-1117 Budapest, Hungary
| | - Thomas Peitzmann
- Institute for Subatomic Physics, Utrecht University/Nikhef, Utrecht, Netherlands
| | | | - Pierluigi Piersimoni
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
- UniCamillus-Saint Camillus International University of Health Sciences, Rome, Italy
| | - Maksym Protsenko
- Research and Production Enterprise 'LTU' (RPELTU), Kharkiv, Ukraine
| | - Max Rauch
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Attiq Ur Rehman
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Matthias Richter
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Dieter Röhrich
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Joshua Santana
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 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, NO-5007 Bergen, Norway
- Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Ákos Sudár
- Wigner Research Centre for Physics, Budapest, Hungary
- Budapest University of Technology and Economics, Budapest, Hungary
| | - Ganesh Tambave
- Center for Medical and Radiation Physics (CMRP), National Institute of Science Education and Research (NISER), Bhubaneswar, India
| | - Ihor Tymchuk
- Research and Production Enterprise 'LTU' (RPELTU), Kharkiv, Ukraine
| | - Kjetil Ullaland
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | | | - Lennart Volz
- Biophysics, GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt, Germany
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Boris Wagner
- Department of Physics and Technology, University of Bergen, NO-5007 Bergen, Norway
| | - Steffen Wendzel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
| | - Alexander Wiebel
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
| | - RenZheng Xiao
- Department of Physics and Technology, University of Bergen, NO-5007 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, NO-5007 Bergen, Norway
| | - Sebastian Zillien
- Center for Technology and Transfer (ZTT), University of Applied Sciences Worms, D-67549 Worms, Germany
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Götz S, Dickmann J, Rit S, Krah N, Khellaf F, Schulte RW, Parodi K, Dedes G, Landry G. Evaluation of the impact of a scanner prototype on proton CT and helium CT image quality and dose efficiency with Monte Carlo simulation. Phys Med Biol 2022; 67. [PMID: 35086073 DOI: 10.1088/1361-6560/ac4fa4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/27/2022] [Indexed: 11/12/2022]
Abstract
Objective.The use of ion computed tomography (CT) promises to yield improved relative stopping power (RSP) estimation as input to particle therapy treatment planning. Recently, proton CT (pCT) has been shown to yield RSP accuracy on par with state-of-the-art x-ray dual energy CT. There are however concerns that the lower spatial resolution of pCT compared to x-ray CT may limit its potential, which has spurred interest in the use of helium ion CT (HeCT). The goal of this study was to investigate image quality of pCT and HeCT in terms of noise, spatial resolution, RSP accuracy and imaging dose using a detailed Monte Carlo (MC) model of an existing ion CT prototype.Approach.Three phantoms were used in simulated pCT and HeCT scans allowing estimation of noise, spatial resolution and the scoring of dose. An additional phantom was used to evaluate RSP accuracy. The imaging dose required to achieve the same image noise in a water and a head phantom was estimated at both native spatial resolution, and in a scenario where the HeCT spatial resolution was reduced and matched to that of pCT using Hann windowing of the reconstruction filter. A variance reconstruction formalism was adapted to account for Hann windowing.Main results.We confirmed that the scanner prototype would produce higher spatial resolution for HeCT than pCT by a factor 1.8 (0.86 lp mm-1versus 0.48 lp mm-1at the center of a 20 cm water phantom). At native resolution, HeCT required a factor 2.9 more dose than pCT to achieve the same noise, while at matched resolution, HeCT required only 38% of the pCT dose. Finally, RSP mean absolute percent error (MAPE) was found to be 0.59% for pCT and 0.67% for HeCT.Significance.This work compared the imaging performance of pCT and HeCT when using an existing scanner prototype, with the spatial resolution advantage of HeCT coming at the cost of increased dose. When matching spatial resolution via Hann windowing, HeCT had a substantial dose advantage. Both modalities provided state-of-the-art RSP MAPE. HeCT might therefore help reduce the dose exposure of patients with comparable image noise to pCT, enhanced spatial resolution and acceptable RSP accuracy at the same time.
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Affiliation(s)
- S Götz
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), D-85748 Garching bei München, Germany
| | - J Dickmann
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), D-85748 Garching bei München, Germany
| | - S Rit
- University of Lyon, INSA-Lyon, Unversité Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS, UMR 5220, U1294 F-69373, Lyon, France
| | - N Krah
- University of Lyon, INSA-Lyon, Unversité Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS, UMR 5220, U1294 F-69373, Lyon, France.,IP2I, UMR 5822 F-69622, Villeurbanne, France
| | - F Khellaf
- University of Lyon, INSA-Lyon, Unversité Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS, UMR 5220, U1294 F-69373, Lyon, France
| | - R W Schulte
- Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, CA 92354, United States of America
| | - K Parodi
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), D-85748 Garching bei München, Germany
| | - G Dedes
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), D-85748 Garching bei München, Germany
| | - G Landry
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), D-85748 Garching bei München, Germany.,Department of Radiation Oncology, University Hospital, LMU Munich, D-81377 Munich, Germany.,German Cancer Consortium (DKTK), D-81377 Munich, Germany
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6
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Censor Y, Schubert KE, Schulte RW. Developments in Mathematical Algorithms and Computational Tools for Proton CT and Particle Therapy Treatment Planning. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2022. [DOI: 10.1109/trpms.2021.3107322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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7
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Volz L, Collins-Fekete CA, Bär E, Brons S, Graeff C, Johnson RP, Runz A, Sarosiek C, Schulte RW, Seco J. The accuracy of helium ion CT based particle therapy range prediction: an experimental study comparing different particle and x-ray CT modalities. Phys Med Biol 2021; 66:10.1088/1361-6560/ac33ec. [PMID: 34706355 PMCID: PMC8792995 DOI: 10.1088/1361-6560/ac33ec] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 10/27/2021] [Indexed: 11/12/2022]
Abstract
This work provides a quantitative assessment of helium ion CT (HeCT) for particle therapy treatment planning. For the first time, HeCT based range prediction accuracy in a heterogeneous tissue phantom is presented and compared to single-energy x-ray CT (SECT), dual-energy x-ray CT (DECT) and proton CT (pCT). HeCT and pCT scans were acquired using the US pCT collaboration prototype particle CT scanner at the Heidelberg Ion-Beam Therapy Center. SECT and DECT scans were done with a Siemens Somatom Definition Flash and converted to RSP. A Catphan CTP404 module was used to study the RSP accuracy of HeCT. A custom phantom of 20 cm diameter containing several tissue equivalent plastic cubes was used to assess the spatial resolution of HeCT and compare it to DECT. A clinically realistic heterogeneous tissue phantom was constructed using cranial slices from a pig head placed inside a cylindrical phantom (ø150 mm). A proton beam (84.67 mm range) depth-dose measurement was acquired using a stack of GafchromicTM EBT-XD films in a central dosimetry insert in the phantom. CT scans of the phantom were acquired with each modality, and proton depth-dose estimates were simulated based on the reconstructions. The RSP accuracy of HeCT for the plastic phantom was found to be 0.3 ± 0.1%. The spatial resolution for HeCT of the cube phantom was 5.9 ± 0.4 lp cm-1for central, and 7.6 ± 0.8 lp cm-1for peripheral cubes, comparable to DECT spatial resolution (7.7 ± 0.3 lp cm-1and 7.4 ± 0.2 lp cm-1, respectively). For the pig head, HeCT, SECT, DECT and pCT predicted range accuracy was 0.25%, -1.40%, -0.45% and 0.39%, respectively. In this study, HeCT acquired with a prototype system showed potential for particle therapy treatment planning, offering RSP accuracy, spatial resolution, and range prediction accuracy comparable to that achieved with a commercial DECT scanner. Still, technical improvements of HeCT are needed to enable clinical implementation.
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Affiliation(s)
- L Volz
- Department of Biomedical Physics in Radiation Oncology, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany
- Department of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
| | - C-A Collins-Fekete
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - E Bär
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
- Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - S Brons
- Heidelberg Ion-Beam Therapy Center, Universitäts Klinikum Heidelberg, Heidelberg, Germany
| | - C Graeff
- Biophysics, GSI Helmholtz Center for Heavy Ion Research GmbH, Darmstadt, Germany
| | - R P Johnson
- Department of Physics, University of California at Santa Cruz, Santa Cruz, United States of America
| | - A Runz
- Department of Medical Physics in Radiation Therapy, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany
| | - C Sarosiek
- Department of Physics, Northern Illinois University, DeKalb, United States of America
| | - R W Schulte
- Department of Basic Sciences, Division of Biomedical Engineering Sciences, Loma Linda University, Loma Linda, United States of America
| | - J Seco
- Department of Biomedical Physics in Radiation Oncology, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg, Germany
- Department of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
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8
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Dickmann J, Sarosiek C, Götz S, Pankuch M, Coutrakon G, Johnson RP, Schulte RW, Parodi K, Landry G, Dedes G. An empirical artifact correction for proton computed tomography. Phys Med 2021; 86:57-65. [PMID: 34058718 DOI: 10.1016/j.ejmp.2021.05.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/20/2021] [Accepted: 05/12/2021] [Indexed: 12/31/2022] Open
Abstract
PURPOSE To reduce image artifacts of proton computed tomography (pCT) from a preclinical scanner, for imaging of the relative stopping power (RSP) needed for particle therapy treatment planning using a simple empirical artifact correction method. METHODS We adapted and employed a correction method previously used for beam-hardening correction in x-ray CT which makes use of a single scan of a custom-built homogeneous phantom with known RSP. Exploiting the linearity of the filtered backprojection operation, a function was found which corrects water-equivalent path lengths (RSP line integrals) in experimental scans using a prototype pCT scanner. The correction function was applied to projection values of subsequent scans of a homogeneous water phantom, a sensitometric phantom with various inserts and an anthropomorphic head phantom. Data were acquired at two different incident proton energies to test the robustness of the method. RESULTS Inaccuracies in the detection process caused an offset and known ring artifacts in the water phantom which were considerably reduced using the proposed method. The mean absolute percentage error (MAPE) of mean RSP values of all inserts of the sensitometric phantom and the water phantom was reduced from 0.87% to 0.44% and from 0.86% to 0.48% for the two incident energies respectively. In the head phantom a clear reduction of artifacts was observed. CONCLUSIONS Image artifacts of experimental pCT scans with a prototype scanner could substantially be reduced both in homogeneous, heterogeneous and anthropomorphic phantoms. RSP accuracy was also improved.
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Affiliation(s)
- Jannis Dickmann
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), Am Coulombwall 1, Garching bei München, Germany.
| | - Christina Sarosiek
- Department of Physics, Northern Illinois University, 1425 W. Lincoln Highway, DeKalb, Illinois, United States.
| | - Stefanie Götz
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), Am Coulombwall 1, Garching bei München, Germany.
| | - Mark Pankuch
- Northwestern Medicine Chicago Proton Center, 4455 Weaver Parkway, Warrenville, Illinois, United States.
| | - George Coutrakon
- Department of Physics, Northern Illinois University, 1425 W. Lincoln Highway, DeKalb, Illinois, United States.
| | - Robert P Johnson
- Department of Physics, U.C. Santa Cruz, 1156 High Street, Santa Cruz, California, United States.
| | - Reinhard W Schulte
- Division of Biomedical Engineering Sciences, Loma Linda University, 11175 Campus Street, Loma Linda, California, United States.
| | - Katia Parodi
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), Am Coulombwall 1, Garching bei München, Germany.
| | - Guillaume Landry
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), Am Coulombwall 1, Garching bei München, Germany; Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, Munich, Germany; German Cancer Consortium (DKTK), Marchioninistraße 15, Munich, Germany.
| | - George Dedes
- Department of Medical Physics, Fakultät für Physik, Ludwig-Maximilians-Universität München (LMU Munich), Am Coulombwall 1, Garching bei München, Germany.
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9
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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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10
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Azimbagirad M, Grillo FW, Hadadian Y, Carneiro AAO, Murta LO. Biomimetic phantom with anatomical accuracy for evaluating brain volumetric measurements with magnetic resonance imaging. J Med Imaging (Bellingham) 2021; 8:013503. [PMID: 33532513 PMCID: PMC7844423 DOI: 10.1117/1.jmi.8.1.013503] [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] [Received: 04/01/2020] [Accepted: 01/11/2021] [Indexed: 11/14/2022] Open
Abstract
Purpose: Brain image volumetric measurements (BVM) methods have been used to quantify brain tissue volumes using magnetic resonance imaging (MRI) when investigating abnormalities. Although BVM methods are widely used, they need to be evaluated to quantify their reliability. Currently, the gold-standard reference to evaluate a BVM is usually manual labeling measurement. Manual volume labeling is a time-consuming and expensive task, but the confidence level ascribed to this method is not absolute. We describe and evaluate a biomimetic brain phantom as an alternative for the manual validation of BVM. Methods: We printed a three-dimensional (3D) brain mold using an MRI of a three-year-old boy diagnosed with Sturge-Weber syndrome. Then we prepared three different mixtures of styrene-ethylene/butylene-styrene gel and paraffin to mimic white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF). The mold was filled by these three mixtures with known volumes. We scanned the brain phantom using two MRI scanners, 1.5 and 3.0 Tesla. Our suggestion is a new challenging model to evaluate the BVM which includes the measured volumes of the phantom compartments and its MRI. We investigated the performance of an automatic BVM, i.e., the expectation-maximization (EM) method, to estimate its accuracy in BVM. Results: The automatic BVM results using the EM method showed a relative error (regarding the phantom volume) of 0.08, 0.03, and 0.13 ( ± 0.03 uncertainty) percentages of the GM, CSF, and WM volume, respectively, which was in good agreement with the results reported using manual segmentation. Conclusions: The phantom can be a potential quantifier for a wide range of segmentation methods.
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Affiliation(s)
- Mehran Azimbagirad
- University of Western Brittany, Faculty of Medicine and Health Sciences, Brest, France
- University of São Paulo, Department of Physics, Faculty of Philosophy, Science and Languages, Ribeirão Preto, São Paulo, Brazil
| | - Felipe Wilker Grillo
- University of São Paulo, Department of Physics, Faculty of Philosophy, Science and Languages, Ribeirão Preto, São Paulo, Brazil
| | - Yaser Hadadian
- University of São Paulo, Department of Physics, Faculty of Philosophy, Science and Languages, Ribeirão Preto, São Paulo, Brazil
| | | | - Luiz Otavio Murta
- University of São Paulo, Department of Computing and Mathematics, Faculty of Philosophy, Science and Languages, Ribeirão Preto, São Paulo, Brazil
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11
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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 2020; 32:23-38. [PMID: 32798033 PMCID: PMC9948882 DOI: 10.1016/j.zemedi.2020.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [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 Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching b. München, Germany,Department of Radiation Oncology, Department of Medical Physics, University Hospital, LMU Munich, Munich, Germany,German Cancer Consortium, (DKTK), Munich, Germany
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12
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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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13
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Dickmann J, Rit S, Pankuch M, Johnson RP, Schulte RW, Parodi K, Dedes G, Landry G. An optimization algorithm for dose reduction with fluence‐modulated proton CT. Med Phys 2020; 47:1895-1906. [DOI: 10.1002/mp.14084] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 01/30/2020] [Accepted: 02/05/2020] [Indexed: 01/12/2023] Open
Affiliation(s)
- J. Dickmann
- Department of Medical Physics Faculty of Physics Ludwig‐Maximilians‐Universität München Am Coulombwall 1 85748 Garching b. München Germany
| | - S. Rit
- Univ Lyon INSA‐Lyon Université Claude Bernard Lyon 1 UJM‐Saint Étienne CNRS, Inserm CREATIS UMR 5220 U1206 F‐69373 Lyon France
| | - M. Pankuch
- Northwestern Medicine Chicago Proton Center Warrenville IL 60555 USA
| | - R. P. Johnson
- Department of Physics University of California Santa Cruz Santa Cruz CA 95064 USA
| | - R. W. Schulte
- Division of Biomedical Engineering Sciences Loma Linda University Loma Linda CA 92354 USA
| | - K. Parodi
- Department of Medical Physics Faculty of Physics Ludwig‐Maximilians‐Universität München Am Coulombwall 1 85748 Garching b. München Germany
| | - G. Dedes
- Department of Medical Physics Faculty of Physics Ludwig‐Maximilians‐Universität München Am Coulombwall 1 85748 Garching b. München Germany
| | - G. Landry
- Department of Medical Physics Faculty of Physics Ludwig‐Maximilians‐Universität München Am Coulombwall 1 85748 Garching b. München Germany
- Department of Radiation Oncology University Hospital, LMU Munich 81377 Munich Germany
- German Cancer Consortium (DKTK) 81377 Munich Germany
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14
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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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15
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Han MC, Ku Y, Lee HS, Yeom YS, Han H, Kim CH. New calculation method for 3D dose distribution in tetrahedral-mesh phantoms in Geant4. Phys Med 2019; 66:97-103. [PMID: 31585335 DOI: 10.1016/j.ejmp.2019.09.239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/27/2019] [Accepted: 09/23/2019] [Indexed: 11/18/2022] Open
Abstract
The tetrahedral-mesh (TM) geometry, which is a very promising geometry for computational human phantoms, has a limitation in 3D dose distribution calculation for medical applications. Even though Geant4 provides the read-out geometry for calculating 3D dose distribution in the TM geometry, this method significantly slows down the computation speed. In the present study, we developed a new method, called Moving Voxel-based Dose-Distribution Calculator (MVDDC), to rapidly calculate a 3D dose distribution in a TM geometry. To evaluate the performance of the MVDDC method, a simple TM cubic phantom and a human phantom were implemented in Geant4. Subsequently, the phantoms were irradiated with proton spot beams under various conditions, and the obtained results were compared with those of the read-out geometry method. The results show that there is no significant difference between the dose distributions calculated using the new method and the read-out geometry method. With respect to the computational performance, the speeds of simulations using the MVDDC were approximately 1.4-2.7 times faster than those of the simulations using the read-out geometry method.
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Affiliation(s)
- Min Cheol Han
- Department of Radiation Oncology, Yonsei University College of Medicine, Seoul 03722, South Korea
| | - Youngmo Ku
- Department of Nuclear Engineering, Hanyang University, Seoul 04763, South Korea
| | - Hyun Su Lee
- Department of Nuclear Engineering, Hanyang University, Seoul 04763, South Korea
| | - Yeon Soo Yeom
- Division of Cancer Epidemiology & Genetics, National Cancer Institute, MD 20892-9760, USA
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, Seoul 04763, South Korea
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Seoul 04763, South Korea.
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16
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Michelet C, Li Z, Yang W, Incerti S, Desbarats P, Giovannelli JF, Barberet P, Delville MH, Gordillo N, Devès G, Seznec H. A Geant4 simulation for three-dimensional proton imaging of microscopic samples. Phys Med 2019; 65:172-180. [PMID: 31494371 DOI: 10.1016/j.ejmp.2019.08.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 08/29/2019] [Accepted: 08/29/2019] [Indexed: 11/18/2022] Open
Abstract
Proton imaging can be carried out on microscopic samples by focusing the beam to a diameter ranging from a few micrometers down to a few tens of nanometers, depending on the required beam intensity and spatial resolution. Three-dimensional (3D) imaging by tomography is obtained from proton transmission (STIM: Scanning Transmission Ion Microscopy) and/or X-ray emission (PIXE: Particle Induced X-ray Emission). In these experiments, the samples are dehydrated for under vacuum analysis. In situ quantification of nanoparticles has been carried out at CENBG in the frame of nanotoxicology studies, on cells and small organisms used as biological models, especially on Caenorhabditis elegans (C. elegans) nematodes. Tomography experiments reveal the distribution of mass density and chemical content (in g.cm-3) within the analyzed volume. These density values are obtained using an inversion algorithm. To investigate the effect of this data reduction process, we defined different numerical phantoms, including a (dehydrated) C. elegans phantom whose geometry and density were derived from experimental data. A Monte Carlo simulation based on the Geant4 toolkit was developed. Using different simulation and reconstruction conditions, we compared the resulting tomographic images to the initial numerical reference phantom. A study of the relative error between the reconstructed and the reference images lead to the result that 20 protons per shot can be considered as an optimal number for 3D STIM imaging. Preliminary results for PIXE tomography are also presented, showing the interest of such numerical phantoms to produce reference data for future studies on X-ray signal attenuation in thick samples.
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Affiliation(s)
- Claire Michelet
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France.
| | - Zhuxin Li
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France
| | - Wen Yang
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France
| | - Sébastien Incerti
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France.
| | - Pascal Desbarats
- Laboratoire Bordelais de Recherche en Informatique (LaBRI, UMR5800) Univ. Bordeaux, 351 Cours de la Libération, F-33405 Talence cedex, France.
| | | | - Philippe Barberet
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France.
| | - Marie-Hélène Delville
- CNRS, Univ. Bordeaux, ICMCB, UMR5026, 87 avenue du Dr. A. Schweitzer, Pessac F-33608, France.
| | - Nuria Gordillo
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France
| | - Guillaume Devès
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France.
| | - Hervé Seznec
- CENBG, UMR5797, Université de Bordeaux, CNRS, F-33170 Gradignan, France.
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17
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Dickmann J, Wesp P, Rädler M, Rit S, Pankuch M, Johnson RP, Bashkirov V, Schulte RW, Parodi K, Landry G, Dedes G. Prediction of image noise contributions in proton computed tomography and comparison to measurements. ACTA ACUST UNITED AC 2019; 64:145016. [DOI: 10.1088/1361-6560/ab2474] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Poder J, Cutajar D, Guatelli S, Petasecca M, Howie A, Bucci J, Carrara M, Rosenfeld A. A Monte Carlo study on the feasibility of real-time in vivo source tracking during ultrasound based HDR prostate brachytherapy treatments. Phys Med 2019; 59:30-36. [DOI: 10.1016/j.ejmp.2019.02.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/14/2018] [Accepted: 02/14/2019] [Indexed: 10/27/2022] Open
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19
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Poder J, Cutajar D, Guatelli S, Petasecca M, Howie A, Bucci J, Rosenfeld A. HDR brachytherapy in vivo source position verification using a 2D diode array: A Monte Carlo study. J Appl Clin Med Phys 2018; 19:163-172. [PMID: 29855128 PMCID: PMC6036394 DOI: 10.1002/acm2.12360] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 03/21/2018] [Accepted: 04/18/2018] [Indexed: 11/23/2022] Open
Abstract
PURPOSE This study aims to assess the accuracy of source position verification during high-dose rate (HDR) prostate brachytherapy using a novel, in-house developed two-dimensional (2D) diode array (the Magic Plate), embedded exactly below the patient within a carbon fiber couch. The effect of tissue inhomogeneities on source localization accuracy is examined. METHOD Monte Carlo (MC) simulations of 12 source positions from a HDR prostate brachytherapy treatment were performed using the Geant4 toolkit. An Ir-192 Flexisource (Isodose Control, Veenendaal, the Netherlands) was simulated inside a voxelized patient geometry, and the dose deposited in each detector of the Magic Plate evaluated. The dose deposited in each detector was then used to localize the source position using a proprietary reconstruction algorithm. RESULTS The accuracy of source position verification using the Magic Plate embedded in the patient couch was found to be affected by the tissue inhomogeneities within the patient, with an average difference of 2.1 ± 0.8 mm (k = 1) between the Magic Plate predicted and known source positions. Recalculation of the simulations with all voxels assigned a density of water improved this verification accuracy to within 1 mm. CONCLUSION Source position verification using the Magic Plate during a HDR prostate brachytherapy treatment was examined using MC simulations. In a homogenous geometry (water), the Magic Plate was able to localize the source to within 1 mm, however, the verification accuracy was negatively affected by inhomogeneities; this can be corrected for by using density information obtained from CT, making the proposed tool attractive for use as a real-time in vivo quality assurance (QA) device in HDR brachytherapy for prostate cancer.
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Affiliation(s)
- Joel Poder
- Centre of Medical Radiation PhysicsUniversity of WollongongWollongongNSWAustralia
- St George Hospital Cancer Care CentreKogarahNSWAustralia
| | - Dean Cutajar
- Centre of Medical Radiation PhysicsUniversity of WollongongWollongongNSWAustralia
- St George Hospital Cancer Care CentreKogarahNSWAustralia
| | - Susanna Guatelli
- Centre of Medical Radiation PhysicsUniversity of WollongongWollongongNSWAustralia
| | - Marco Petasecca
- Centre of Medical Radiation PhysicsUniversity of WollongongWollongongNSWAustralia
| | - Andrew Howie
- St George Hospital Cancer Care CentreKogarahNSWAustralia
| | - Joseph Bucci
- St George Hospital Cancer Care CentreKogarahNSWAustralia
| | - Anatoly Rosenfeld
- Centre of Medical Radiation PhysicsUniversity of WollongongWollongongNSWAustralia
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20
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Giacometti V, Bashkirov VA, Piersimoni P, Guatelli S, Plautz TE, Sadrozinski HF, Johnson RP, Zatserklyaniy A, Tessonnier T, Parodi K, Rosenfeld AB, Schulte RW. Software platform for simulation of a prototype proton
CT
scanner. Med Phys 2017; 44:1002-1016. [DOI: 10.1002/mp.12107] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 12/21/2016] [Accepted: 01/04/2017] [Indexed: 01/14/2023] Open
Affiliation(s)
- Valentina Giacometti
- Centre for Medical Radiation Physics University of Wollongong Wollongong NSW Australia
- Division of Radiation Research Department of Basic Sciences Loma Linda University Loma Linda CA USA
| | - Vladimir A. Bashkirov
- Division of Radiation Research Department of Basic Sciences Loma Linda University Loma Linda CA USA
| | | | - Susanna Guatelli
- Centre for Medical Radiation Physics University of Wollongong Wollongong NSW Australia
| | - Tia E. Plautz
- Santa Cruz Institute for Particle Physics Santa Cruz CA USA
| | | | | | | | - Thomas Tessonnier
- Department of Radiation Oncology Heidelberg University Clinic Heidelberg Germany
- Department of Medical Physics Ludwig‐Maximilians Universität München Munich Germany
| | - Katia Parodi
- Department of Medical Physics Ludwig‐Maximilians Universität München Munich Germany
- Heidelberg Ion Beam Therapy Center Heidelberg Germany
| | - Anatoly B. Rosenfeld
- Centre for Medical Radiation Physics University of Wollongong Wollongong NSW Australia
| | - Reinhard W. Schulte
- Division of Radiation Research Department of Basic Sciences Loma Linda University Loma Linda CA USA
- Department of Radiation Oncology University of California San Francisco CA USA
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21
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Guatelli S, Incerti S. Monte Carlo simulations for medical physics: From fundamental physics to cancer treatment. Phys Med 2017; 33:179-181. [PMID: 28111100 DOI: 10.1016/j.ejmp.2017.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 01/02/2017] [Indexed: 01/11/2023] Open
Affiliation(s)
- S Guatelli
- Centre For Medical Radiation Physics (CMRP), University of Wollongong (UOW), Wollongong, NSW, Australia.
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