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Lim Joon D, Berry C, Harris B, Tacey M, Smith D, Lawrentschuk N, Schneider ME, Fraser O, Hall M, Chao M, Foroudi F, Jenkins T, Angus D, Wada M, Sengupta S, Khoo V. A clinical study comparing polymer and gold fiducials for prostate cancer radiotherapy. Front Oncol 2023; 12:1023288. [PMID: 36818674 PMCID: PMC9930895 DOI: 10.3389/fonc.2022.1023288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 12/30/2022] [Indexed: 02/04/2023] Open
Abstract
Introduction Image guidance with gold fiducials improves outcomes of prostate radiotherapy. However, gold produces artefact on CT imaging, interfering with contouring and verification. The purpose of this study was to compare polymer to standard gold fiducials using radiotherapy imaging modalities to assess the visibility and artefact. Methods Twenty eight patients with locally advanced prostate cancer were enrolled, half had three polymer fiducials implanted into the prostate and half underwent insertion of gold fiducials. Patients were imaged with CT, T2 weighted MRI, cone-beam CT (CBCT) and planar KV images. Fiducials were scored for visibility and assessed for CT artefact in surrounding prostate tissue. The artefact was quantified from Hounsfield number histograms and separated into percentile ranges and proportion of voxels in HU normal tissue range of a 2cm sphere surrounding the fiducial. Results Gold and polymer fiducials were sufficiently visible for CT and CBCT verification. The gold fiducials could be visualized well on KV planar imaging; however, the polymer markers were obscured by pelvic bones. Neither polymer nor gold fiducials could be visualized on MRI. The polymer fiducial produced less artefact than gold on CT, having less voxel spread for the HU percentile ranges and a greater proportion of voxels in the normal tissue range. Conclusions Polymer fiducials are a more suitable fiducial than gold for CT/CBCT in prostate cancer radiotherapy, demonstrating minimal artefact and good visibility on CT. However, they were not well seen on MRI or KV imaging and thus not suitable for co-registration or planar KV verification.
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Affiliation(s)
- Daryl Lim Joon
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia,*Correspondence: Daryl Lim Joon,
| | - Colleen Berry
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Benjamin Harris
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Mark Tacey
- Office of Research, The Northern Hospital, Epping, VIC, Australia,Melbourne School of Population and Global Health, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Carlton, VIC, Australia
| | - Drew Smith
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | | | | | - Olivia Fraser
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Megan Hall
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Michael Chao
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Farshad Foroudi
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Trish Jenkins
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - David Angus
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Morikatsu Wada
- Radiation Oncology Department, Olivia Newton-John Cancer Centre, Heidelberg, VIC, Australia
| | - Shomik Sengupta
- Austin Health, University of Melbourne, Melbourne, VIC, Australia,*Correspondence: Daryl Lim Joon,
| | - Vincent Khoo
- Department of Clinical Oncology, Royal Marsden Hospital, London, United Kingdom,*Correspondence: Daryl Lim Joon,
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Mylonas A, Booth J, Nguyen DT. A review of artificial intelligence applications for motion tracking in radiotherapy. J Med Imaging Radiat Oncol 2021; 65:596-611. [PMID: 34288501 DOI: 10.1111/1754-9485.13285] [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: 03/05/2021] [Accepted: 06/29/2021] [Indexed: 11/28/2022]
Abstract
During radiotherapy, the organs and tumour move as a result of the dynamic nature of the body; this is known as intrafraction motion. Intrafraction motion can result in tumour underdose and healthy tissue overdose, thereby reducing the effectiveness of the treatment while increasing toxicity to the patients. There is a growing appreciation of intrafraction target motion management by the radiation oncology community. Real-time image-guided radiation therapy (IGRT) can track the target and account for the motion, improving the radiation dose to the tumour and reducing the dose to healthy tissue. Recently, artificial intelligence (AI)-based approaches have been applied to motion management and have shown great potential. In this review, four main categories of motion management using AI are summarised: marker-based tracking, markerless tracking, full anatomy monitoring and motion prediction. Marker-based and markerless tracking approaches focus on tracking the individual target throughout the treatment. Full anatomy algorithms monitor for intrafraction changes in the full anatomy within the field of view. Motion prediction algorithms can be used to account for the latencies due to the time for the system to localise, process and act.
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Affiliation(s)
- Adam Mylonas
- ACRF Image X Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,School of Biomedical Engineering, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Jeremy Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, New South Wales, Australia.,Institute of Medical Physics, School of Physics, The University of Sydney, Sydney, New South Wales, Australia
| | - Doan Trang Nguyen
- ACRF Image X Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,School of Biomedical Engineering, University of Technology Sydney, Sydney, New South Wales, Australia.,Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, New South Wales, Australia
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3
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A phantom study to contrast and compare polymer and gold fiducial markers in radiotherapy simulation imaging. Sci Rep 2021; 11:8931. [PMID: 33903651 PMCID: PMC8076319 DOI: 10.1038/s41598-021-88300-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 04/06/2021] [Indexed: 11/15/2022] Open
Abstract
To assess visibility and artifact characteristics of polymer fiducials compared to standard gold fiducials for radiotherapy CT and MRI simulation. Three gold and three polymer fiducials were inserted into a CT and MRI tissue-equivalent phantom that approximated the prostate cancer radiotherapy configuration. The phantom and fiducials were imaged on CT and MRI. Images were assessed in terms of fiducial visibility and artifact. ImageJ was employed to quantify the pixel gray-scale of each fiducial and artifact. Fiducial gray-scale histograms and profiles were generated for analysis. Objective measurements of the contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and artifact index (AI) were calculated. The CT images showed that the gold fiducials are visually brighter, with greater contrast than the polymer. The higher peak values illustrate this in the line profiles. However, they produce bright radiating and dark shadowing artifacts. This is depicted by the greater width of line profiles and the disruption of phantom area profiles. Quantitatively this results in greater percentile ranges of the histograms. Furthermore, for CT, gold had a higher CNR than polymer, relative to the phantom. However, the gold CNR and SNR were degraded by the greater artifact and thus AI. Both fiducials were visible on MRI and had similar histograms and profiles that were also reflected in comparable CNR, SNR and AI. Polymer fiducials were well visualized in a phantom on CT and MR and produce less artifact than the gold fiducials. Polymer markers could enhance the quality and accuracy of radiotherapy co-registration and planning but require clinical confirmation.
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4
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Sagara T, Kato T, Murakami M. Biological impact of dosimetric perturbations of a fiducial marker and the daily number of fields in proton therapy for prostate cancer. Biomed Phys Eng Express 2021; 7:025007. [PMID: 33522497 DOI: 10.1088/2057-1976/abd9d4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this study was to estimate the biological impact of dosimetric perturbations of a fiducial marker and the daily number of fields in proton therapy for prostate cancer. Using a linear-quadratic model, normalized total doses (NTDs) of points where deposited dose was reduced from the prescribed dose by dosimetric perturbation of a fiducial marker were calculated in two hypothetical prostate cancer treatment schedules: a) irradiation of both parallel-opposed lateral fields and b) irradiation of alternate field in each daily treatment. The impact of hypofractionation and sublethal damage repair between irradiation on NTD was also estimated. The NTD of two fields/day schedule becomes lower than that of one field/day schedule. The difference becomes larger as dose reduction from one of two fields becomes more enhanced. The NTD reduction from the total dose in the two fields/day schedule is largest (30% of total dose) where the dose from one beam is completely lost by a fiducial marker. In contrast, the NTD reduction from the total dose in the one field/day schedule is largest (9% of total dose) where the half dose from one beam is decreased by a fiducial marker. In addition, the NTD reduction becomes larger as the fractional dose increases in a hypofractionated regimen, and when the effect of sublethal damage repair was incorporated. These influences become significant in prostate cancer since the radiobiological sensitivity α/β of prostate cancer is lower than other cancer types and normal tissues late complication. Treating with one alternate field in a daily treatment can improve a deteriorating treatment effect by dosimetric distortion of a fiducial marker in prostate cancer treatment. However, the choice of the number of beams in a fraction must also be determined by considering the sparing of normal tissues and patient-specific status.
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Affiliation(s)
- Tatstuhiko Sagara
- Department of Radiation Physics and Technology, Southern Tohoku Proton Therapy Center, Fukushima, Japan
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5
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Kasanda E, Burbadge C, Bildstein V, Turko J, Spyrou A, Höhr C, Mücher D. GEANT4 simulation of a range verification method using delayed γ spectroscopy of a 92Mo marker. Phys Med Biol 2020; 65:245047. [PMID: 33331299 DOI: 10.1088/1361-6560/abbd15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this work, we propose a novel technique for in-vivo proton therapy range verification. This technique makes use of a molybdenum hadron tumour marker, implanted at a short distance from the clinical treatment volume. Signals emitted from the marker during treatment can provide a direct measurement of the proton beam energy at the marker's position. Fusion-evaporation reactions between the proton beam and marker nucleus result in the emission of delayed characteristic γ rays, which are detected off-beam for an improved signal-to-noise ratio. In order to determine the viability of this technique and to establish an experimental setup for future work, the Monte Carlo package GEANT4 was used in combination with ROOT to simulate a treatment scenario with the new method outlined in this work. These simulations show that the intensity of delayed γ rays produced from competing reactions yields a precise measurement of the range of the proton beam relative to the marker, with sub-millimetre uncertainty.
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Affiliation(s)
- E Kasanda
- Department of Physics, University of Guelph, 50 Stone Rd E, Guelph, ON, N1G 2W1, Canada
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Dal Bello R, Magalhaes Martins P, Graça J, Hermann G, Kihm T, Seco J. Results from the experimental evaluation of CeBr 3 scintillators for 4 He prompt gamma spectroscopy. Med Phys 2019; 46:3615-3626. [PMID: 31087394 DOI: 10.1002/mp.13594] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 05/08/2019] [Accepted: 05/08/2019] [Indexed: 12/16/2022] Open
Abstract
PURPOSE The presence of range uncertainties hinders the exploitation of the full potential of charged particle therapy. Several range verification techniques have been proposed to mitigate this limitation. Prompt gamma spectroscopy (PGS) is among the most promising solutions for online and in vivo range verification. In this work, we present the experimental results of the detection of prompt gamma radiation, induced by 4 He beams at the Heidelberg Ion-Beam Therapy Center (HIT). The results were obtained, using a spectroscopic unit of which the design has been optimized using Monte Carlo simulations. METHODS The spectroscopic unit is composed by a primary cerium bromide (CeBr 3 ) crystal surrounded by a secondary bismuth germanate (BGO) crystal for anticoincidence detection (AC). The digitalization of the signals is performed with an advanced FADC/FPGA system. The 4 He beams at clinical energies and intensities are delivered to multiple targets in the experimental cave at the HIT. We analyze the production of prompt gamma on oxygen and carbon targets, as well as high Z materials such as titanium and aluminum. The quantitative analysis includes a systematic comparison of the signal-to-noise ratio (SNR) improvement for the spectral lines when introducing the AC detection. Moreover, the SNR improvement could provide a reduction of the number of events required to draw robust conclusions. We perform a statistic analysis to determine the magnitude of such an effect. RESULTS We present the energy spectra detected by the primary CeBr 3 and the secondary BGO. The combination of these two detectors leads to an average increase of the signal-to-noise ratio by a factor 2.1, which confirms the Monte Carlo predictions. The spectroscopic unit is capable of detecting efficiently the discrete gamma emission over the full energy spectrum. We identify and analyze 19 independent spectral lines in an energy range spacing from E γ = 0.718 MeV to E γ = 6.13 MeV. Moreover, when introducing the AC detection, the number of events required to determine robustly the intensity of the discrete lines decreases. Finally, the analysis of the low-energy reaction lines determines whether a thin metal insert is introduced in the beam direction. CONCLUSIONS This work provides the experimental characterization of the spectroscopy unit in development for range verification through PGS at the HIT. Excellent performances have been demonstrated over the full prompt gamma energy spectrum with 4 He beams at clinical energies and intensities.
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Affiliation(s)
- Riccardo Dal Bello
- Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany.,Department of Physics and Astronomy, Heidelberg University, Neuenheimer Feld 226, Heidelberg, 69120, Germany
| | - Paulo Magalhaes Martins
- Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany.,Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Lisboa, 1749-016, Portugal
| | - João Graça
- Electronic Development Laboratory, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - German Hermann
- Max-Planck-Institute for Nuclear Physics, P.O. Box 103980, Heidelberg, 69029, Germany
| | - Thomas Kihm
- Max-Planck-Institute for Nuclear Physics, P.O. Box 103980, Heidelberg, 69029, Germany
| | - Joao Seco
- Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany.,Department of Physics and Astronomy, Heidelberg University, Neuenheimer Feld 226, Heidelberg, 69120, Germany
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7
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Arjomandy B, Taylor P, Ainsley C, Safai S, Sahoo N, Pankuch M, Farr JB, Yong Park S, Klein E, Flanz J, Yorke ED, Followill D, Kase Y. AAPM task group 224: Comprehensive proton therapy machine quality assurance. Med Phys 2019; 46:e678-e705. [DOI: 10.1002/mp.13622] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 12/11/2022] Open
Affiliation(s)
- Bijan Arjomandy
- Karmanos Cancer Institute at McLaren‐Flint McLaren Proton Therapy Center Flint MI USA
| | - Paige Taylor
- Imaging and Radiation Oncology Core (IROC) Houston University of Texas MD Anderson Cancer Center Houston TX USA
| | | | - Sairos Safai
- Center for Proton Therapy Paul Scherrer Institute Villigen Switzerland
| | - Narayan Sahoo
- University of Texas, MD Anderson Cancer Center Houston TX USA
| | - Mark Pankuch
- Northwestern Medicine Chicago Proton Center Warrenville IL USA
| | - Jonathan B. Farr
- Applications of Detectors and Accelerators to Medicine 1217Meyrin Switzerland
| | | | - Eric Klein
- Rhode Island Hospital, The Warren Alpert Medical School of Brown University Providence RI USA
| | - Jacob Flanz
- Massachusetts General Hospital, Burr Proton Therapy Center Boston MA
- Harvard Medical School Cambridge MA USA
| | | | - David Followill
- Imaging and Radiation Oncology Core (IROC) Houston University of Texas MD Anderson Cancer Center Houston TX USA
| | - Yuki Kase
- Proton Therapy Division Shizuoka Cancer Center Shizuoka Japan
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8
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Gleeson FC, Tryggestad EJ, Remmes NB, Beltran CJ, Kruse JJ, Haddock MG, Hallemeier CL, Storm AC, Levy MJ. Knowledge of endoscopic ultrasound-delivered fiducial composition and dimension necessary when planning proton beam radiotherapy. Endosc Int Open 2018; 6:E766-E768. [PMID: 29876514 PMCID: PMC5988542 DOI: 10.1055/a-0588-4800] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/05/2018] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND AND STUDY AIMS Little consideration has been given to selection of endoscopic ultrasound-guided fiducials for proton radiotherapy and the resulting perturbations in the therapy dose and pattern. Our aim was to assess the impact of perturbations caused by six fiducials of different composition and dimensions in a phantom gel model. MATERIALS AND METHODS The phantom was submerged in a water bath and irradiated with a uniform 10 cm × 10 cm field of 119.7 MeV monoenergetic spot scanning protons delivered through a 45 mm range shifter. The proton "Bragg Peak" was evaluated. RESULTS Dose perturbations manifesting as dose reductions up to 30 % were observed. A carbon composite (1 × 5 mm) and gold (0.4 × 10 mm) fiducial with backload potential rather than dedicated EUS pre-loaded gold fiducial needles had the best performance in terms of minimizing the dose perturbation. CONCLUSIONS Our data demonstrate that a carbon composite fiducial has a less untoward effect on proton therapy dose distribution than dedicated EUS pre-loaded gold fiducial needles. Such information is important to consider when selecting fiducials specifically for proton therapy.
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Affiliation(s)
- Ferga C. Gleeson
- Division of Gastroenterology & Hepatology, Mayo Clinic Rochester, Minnesota, United States,Corresponding author Ferga C. Gleeson, MD Mayo ClinicDivision of Gastroenterology & Hepatology
200 1
st
St SW
Rochester MN 55905, USA+1-507-266-3931
| | - Erik J. Tryggestad
- Department of Radiation Oncology, Mayo Clinic Rochester, Minnesota, United States
| | - Nicholas B. Remmes
- Department of Radiation Oncology, Mayo Clinic Rochester, Minnesota, United States
| | - Chris J. Beltran
- Department of Radiation Oncology, Mayo Clinic Rochester, Minnesota, United States
| | - Jon J. Kruse
- Department of Radiation Oncology, Mayo Clinic Rochester, Minnesota, United States
| | - Michael G. Haddock
- Department of Radiation Oncology, Mayo Clinic Rochester, Minnesota, United States
| | | | - Andrew C. Storm
- Division of Gastroenterology & Hepatology, Mayo Clinic Rochester, Minnesota, United States
| | - Michael J. Levy
- Division of Gastroenterology & Hepatology, Mayo Clinic Rochester, Minnesota, United States
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9
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Terunuma T, Tokui A, Sakae T. Novel real-time tumor-contouring method using deep learning to prevent mistracking in X-ray fluoroscopy. Radiol Phys Technol 2018; 11:43-53. [PMID: 29285686 PMCID: PMC5840203 DOI: 10.1007/s12194-017-0435-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 12/08/2017] [Accepted: 12/13/2017] [Indexed: 12/25/2022]
Abstract
Robustness to obstacles is the most important factor necessary to achieve accurate tumor tracking without fiducial markers. Some high-density structures, such as bone, are enhanced on X-ray fluoroscopic images, which cause tumor mistracking. Tumor tracking should be performed by controlling "importance recognition": the understanding that soft-tissue is an important tracking feature and bone structure is unimportant. We propose a new real-time tumor-contouring method that uses deep learning with importance recognition control. The novelty of the proposed method is the combination of the devised random overlay method and supervised deep learning to induce the recognition of structures in tumor contouring as important or unimportant. This method can be used for tumor contouring because it uses deep learning to perform image segmentation. Our results from a simulated fluoroscopy model showed accurate tracking of a low-visibility tumor with an error of approximately 1 mm, even if enhanced bone structure acted as an obstacle. A high similarity of approximately 0.95 on the Jaccard index was observed between the segmented and ground truth tumor regions. A short processing time of 25 ms was achieved. The results of this simulated fluoroscopy model support the feasibility of robust real-time tumor contouring with fluoroscopy. Further studies using clinical fluoroscopy are highly anticipated.
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Affiliation(s)
- Toshiyuki Terunuma
- Faculty of Medicine, University of Tsukuba, Ten-nohdai 1-1-1, Tsukuba, 305-8575, Japan.
- Proton Medical Research Center (PMRC), University of Tsukuba Hospital, Amakubo 2-1-1, Tsukuba, 305-8576, Japan.
| | - Aoi Tokui
- Graduate School of Comprehensive Human Science, University of Tsukuba, Ten-nohdai 1-1-1, Tsukuba, 305-8575, Japan
| | - Takeji Sakae
- Faculty of Medicine, University of Tsukuba, Ten-nohdai 1-1-1, Tsukuba, 305-8575, Japan
- Proton Medical Research Center (PMRC), University of Tsukuba Hospital, Amakubo 2-1-1, Tsukuba, 305-8576, Japan
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10
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Oancea C, Ambrožová I, Popescu A, Mytsin G, Vondráček V, Davídková M. LET spectra behind high-density titanium and stainless steel hip implants irradiated with a therapeutic proton beam. RADIAT MEAS 2018. [DOI: 10.1016/j.radmeas.2018.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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11
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Saini J, Bowen SR, James SS, Wong T, Bloch C. Evaluation of ceramic marker for the treatment of ocular melanoma with proton therapy. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa62cf] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Scherman Rydhög J, Perrin R, Jølck RI, Gagnon-Moisan F, Larsen KR, Clementsen P, Riisgaard de Blanck S, Fredberg Persson G, Weber DC, Lomax T, Andresen TL, Munck Af Rosenschold P. Liquid fiducial marker applicability in proton therapy of locally advanced lung cancer. Radiother Oncol 2017; 122:393-399. [PMID: 28104299 DOI: 10.1016/j.radonc.2016.12.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 12/16/2016] [Accepted: 12/23/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE We investigated the clinical applicability of a novel liquid fiducial marker (LFM) for image-guided pencil beam scanned (PBS) proton therapy (PBSPT) of locally advanced lung cancer (LALC). MATERIALS AND METHODS The relative proton stopping power (RSP) of the LFM was calculated and measured. Dose perturbations of the LFM and three solid markers, in a phantom, were measured. PBSPT treatment planning on computer tomography scans of five patients with LALC with the LFM implanted was performed with 1-3 fields. RESULTS The RSP was experimentally determined to be 1.164 for the LFM. Phantom measurements revealed a maximum relative deviation in dose of 4.8% for the LFM in the spread-out Bragg Peak, compared to 12-67% for the solid markers. Using the experimentally determined RSP, the maximum proton range error introduced by the LFM is about 1mm. If the marker was displaced at PBSPT, the maximum dosimetric error was limited to 2 percentage points for 3-field plans. CONCLUSION The dose perturbations introduced by the LFM were considerably smaller than the solid markers investigated. The RSP of the fiducial marker should be corrected in the treatment planning system to avoid errors. The investigated LFM introduced clinically acceptable dose perturbations for image-guided PBSPT of LALC.
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Affiliation(s)
- Jonas Scherman Rydhög
- Department of Oncology, Section of Radiotherapy, 3994, Rigshospitalet, Copenhagen, Denmark; Niels Bohr Institute, University of Copenhagen, Denmark.
| | - Rosalind Perrin
- Paul Scherrer Institut, Center for Proton Therapy, Switzerland
| | - Rasmus Irming Jølck
- DTU Nanotech, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Kgs. Lyngby, Denmark; Nanovi Radiotherapy A/S, Kgs. Lyngby, Denmark
| | | | | | - Paul Clementsen
- Copenhagen Academy for Medical Education and Simulation (CAMES), Rigshospitalet, Copenhagen, Denmark; Department of Internal Medicine, Zealand University Hospital, Roskilde, Denmark
| | | | - Gitte Fredberg Persson
- Department of Oncology, Section of Radiotherapy, 3994, Rigshospitalet, Copenhagen, Denmark
| | | | - Tony Lomax
- Paul Scherrer Institut, Center for Proton Therapy, Switzerland
| | - Thomas Lars Andresen
- DTU Nanotech, Department of Micro- and Nanotechnology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Per Munck Af Rosenschold
- Department of Oncology, Section of Radiotherapy, 3994, Rigshospitalet, Copenhagen, Denmark; Niels Bohr Institute, University of Copenhagen, Denmark
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13
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Jeang EH, Min S, Cho KH, Hwang UJ, Choi SH, Kwak J, Jeong JH, Kim H, Lee SB, Shin D, Park J, Kim JY, Kim DY, Lim YK. Two-dimensional in vivo rectal dosimetry using an endorectal balloon with unfoldable radiochromic film during prostate cancer radiotherapy. Radiother Oncol 2016; 120:327-32. [PMID: 27222297 DOI: 10.1016/j.radonc.2016.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 04/27/2016] [Accepted: 05/05/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND AND PURPOSE The present study aims to investigate the feasibility of two-dimensional (2D) in vivo rectal dosimetry using an endorectal balloon for the radiotherapy of prostate cancer. MATERIALS AND METHODS The endorectal balloon was equipped with an unfoldable radiochromic film. The film was unrolled as the balloon was inflated, and rolled as it was deflated. Its mechanical and imaging properties were tested, and the dosimetric effectiveness was evaluated in clinical photon and proton beams. RESULTS The size of the endorectal balloon including the film was linearly proportional to the volume of water filled in the balloon, and its position could be identified by X-ray radiography. The loss of dose information due to film cutting was within ±1mm from the cutting line. Applying linear interpolation on cut film, the gamma passing rate was more than 95% for 2%/2mm criteria. The measured dose profiles agreed with the plan within 3% and 4% for the photon and proton beams, respectively. A dose-volume histogram of the anterior rectal wall could be obtained from the measured dose distribution in the balloon, which also agreed well with the plan. CONCLUSIONS 2D in vivo rectal dosimetry is feasible using the endorectal balloon with a radiochromic film in the radiotherapy of prostate cancer.
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Affiliation(s)
- Eun Hee Jeang
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Soonki Min
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Kwan Ho Cho
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Ui-Jung Hwang
- Department of Radiation Oncology, National Medical Center, Seoul, Republic of Korea
| | - Sang Hyoun Choi
- Department of Radiation Oncology, Korea Cancer Center Hospital, Seoul, Republic of Korea
| | - Jungwon Kwak
- Department of Radiation Oncology, Asan Medical Center, Seoul, Republic of Korea
| | - Jong Hwi Jeong
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Haksoo Kim
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Se Byeong Lee
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Dongho Shin
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Jeonghoon Park
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Joo-Young Kim
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Dae Yong Kim
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
| | - Young Kyung Lim
- Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea.
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Scherman Rydhög J, Irming Jølck R, Andresen TL, Munck af Rosenschöld P. Quantification and comparison of visibility and image artifacts of a new liquid fiducial marker in a lung phantom for image-guided radiation therapy. Med Phys 2015; 42:2818-26. [DOI: 10.1118/1.4919616] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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15
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Ahn SH, Gil MS, Lee DS, Han Y, Park HC, Sohn JW, Kim HY, Shin EH, Yu JI, Noh JM, Cho JS, Ahn SH, Choi DH. Preclinical investigation for developing injectable fiducial markers using a mixture of BaSO4
and biodegradable polymer for proton therapy. Med Phys 2015; 42:2626-37. [DOI: 10.1118/1.4916663] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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16
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Abstract
The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy.
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Affiliation(s)
- Wayne D Newhauser
- Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA, 70803, USA
- Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA, 70809, USA
| | - Rui Zhang
- Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA, 70803, USA
- Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA, 70809, USA
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17
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Dietlicher I, Casiraghi M, Ares C, Bolsi A, Weber DC, Lomax AJ, Albertini F. The effect of surgical titanium rods on proton therapy delivered for cervical bone tumors: experimental validation using an anthropomorphic phantom. Phys Med Biol 2014; 59:7181-94. [DOI: 10.1088/0031-9155/59/23/7181] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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18
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Ogrinc Potočnik N, Škrášková K, Flinders B, Pelicon P, Heeren RMA. Gold sputtered fiducial markers for combined secondary ion mass spectrometry and MALDI imaging of tissue samples. Anal Chem 2014; 86:6781-5. [PMID: 24918500 DOI: 10.1021/ac500308s] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mass spectrometry imaging (MSI) is a label free technique capable of providing simultaneous identification and localization of biomolecules. A multimodal approach is required that allows for the study of the complexity of biological tissue samples to overcome the limitations of a single MSI technique. Secondary ion mass spectrometry (SIMS) allows for high spatial resolution imaging while matrix-assisted laser desorption (MALDI) offers a significantly wider mass range. The combination of coregistered SIMS and MALDI images results in detailed and unique biomolecular information. In this Technical Note, we describe how gold sputtered/implanted fiducial markers (FM) are created and can be used to ensure a proper overlay and coregistration of the two-dimensional images provided by the two MSI modalities.
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19
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Dolney D, McDonough J, Vapiwala N, Metz JM. Dose perturbations by electromagnetic transponders in the proton environment. Phys Med Biol 2013; 58:1495-505. [PMID: 23403457 DOI: 10.1088/0031-9155/58/5/1495] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Surgically implanted electromagnetic transponders have been used in external beam radiotherapy for target localization and position monitoring in real time. The effect of transponders on proton therapy dose distributions has not been reported. A Monte Carlo implementation of the transponder geometry is validated against film measurements in a proton SOBP and subsequently used to generate dose distributions for transponders at different positions and orientations in the proton SOBP. The maximum dose deficit is extracted in each case. Dose shadows of up to 60% occur for transponders positioned very near the end of range of the Bragg peak. However, if transponders are positioned further than 5 mm from the end of range, and are not oriented parallel to the beam direction, then the dose deficit can be kept below 10%.
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Affiliation(s)
- Derek Dolney
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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20
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Handsfield LL, Yue NJ, Zhou J, Chen T, Goyal S. Determination of optimal fiducial marker across image-guided radiation therapy (IGRT) modalities: visibility and artifact analysis of gold, carbon, and polymer fiducial markers. J Appl Clin Med Phys 2012; 13:3976. [PMID: 22955665 PMCID: PMC5718239 DOI: 10.1120/jacmp.v13i5.3976] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 06/01/2012] [Accepted: 06/04/2012] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study was to evaluate the visibility and artifact created by gold, carbon, and polymer fiducial markers in a simple phantom across computed tomography (CT), kilovoltage (kV), and megavoltage (MV) linear accelerator imaging and MV tomotherapy imaging. Three types of fiducial markers (gold, carbon, and polymer) were investigated for their visibility and artifacts in images acquired with various modalities and with different imaging parameters (kV, mAs, slice thickness). The imaging modalities include kV CT, 2D linac‐based kilovoltage and megavoltage X‐ray imaging systems, kV cone‐beam CT, and normal and fine tomotherapy imaging. The images were acquired on a phantom constructed using Superflab bolus in which markers of each type were inserted into the center layer. The visibility and artifacts produced by each marker were assessed qualitatively and quantitatively. All tested markers could be identified clearly on the acquired CT and linac‐based kV images; gold markers demonstrated the highest contrast. On the CT images, gold markers produced a significant artifact, while no artifacts were observed with polymer markers. Only gold markers were visible when using linac‐based MV and tomotherapy imaging. For linac‐based kV images, the contrast increased with kV and mAs values for all the markers, with the gold being the most pronounced. On CT images, the contrast increased with kV for the gold markers, while decreasing for the polymer and carbon marker. With the bolus phantom used, we found that when kV imaging‐based treatment verification equipment is available, polymer and carbon markers may be the preferred choice for target localization and patient treatment positioning verification due to less image artifacts. If MV imaging will be the sole modality for positioning verification, it may be necessary to use gold markers despite the artifacts they create on the simulation CT images. PACS number: 87
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Affiliation(s)
- Lydia L Handsfield
- Department of Radiation Oncology, The Cancer Institute of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08903, USA
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21
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Matsuura T, Maeda K, Sutherland K, Takayanagi T, Shimizu S, Takao S, Miyamoto N, Nihongi H, Toramatsu C, Nagamine Y, Fujimoto R, Suzuki R, Ishikawa M, Umegaki K, Shirato H. Biological effect of dose distortion by fiducial markers in spot-scanning proton therapy with a limited number of fields: A simulation study. Med Phys 2012; 39:5584-91. [DOI: 10.1118/1.4745558] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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22
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Vassiliev ON, Kudchadker RJ, Kuban DA, Frank SJ, Choi S, Nguyen Q, Lee AK. Dosimetric impact of fiducial markers in patients undergoing photon beam radiation therapy. Phys Med 2012; 28:240-4. [DOI: 10.1016/j.ejmp.2011.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 07/15/2011] [Accepted: 08/12/2011] [Indexed: 11/29/2022] Open
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23
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Improving Positioning in High-Dose Radiotherapy for Prostate Cancer: Safety and Visibility of Frequently Used Gold Fiducial Markers. Int J Radiat Oncol Biol Phys 2012; 83:46-52. [DOI: 10.1016/j.ijrobp.2011.05.058] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 05/28/2011] [Accepted: 05/31/2011] [Indexed: 11/21/2022]
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Chen Y, J O’Connell J, Ko CJ, Mayer RR, Belard A, McDonough JE. Fiducial markers in prostate for kV imaging: quantification of visibility and optimization of imaging conditions. Phys Med Biol 2011; 57:155-72. [DOI: 10.1088/0031-9155/57/1/155] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Huang JY, Newhauser WD, Zhu XR, Lee AK, Kudchadker RJ. Investigation of dose perturbations and the radiographic visibility of potential fiducials for proton radiation therapy of the prostate. Phys Med Biol 2011; 56:5287-302. [PMID: 21799236 PMCID: PMC3171138 DOI: 10.1088/0031-9155/56/16/014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Image guidance using implanted fiducial markers is commonly used to ensure accurate and reproducible target positioning in radiation therapy for prostate cancer. The ideal fiducial marker is clearly visible in kV imaging, does not perturb the therapeutic dose in the target volume and does not cause any artifacts on the CT images used for treatment planning. As yet, ideal markers that fully meet all three of these criteria have not been reported. In this study, 12 fiducial markers were evaluated for their potential clinical utility in proton radiation therapy for prostate cancer. In order to identify the good candidates, each fiducial was imaged using a CT scanner as well as a kV imaging system. Additionally, the dose perturbation caused by each fiducial was quantified using radiochromic film and a clinical proton beam. Based on the results, three fiducials were identified as good candidates for use in proton radiotherapy of prostate cancer.
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Affiliation(s)
- Jessie Y. Huang
- The University of Texas at Houston Graduate School of Biomedical Sciences, 6767 Bertner Avenue, S3.8344, Houston, TX 77030, USA
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 193, Houston, TX 77030, USA
| | - Wayne D. Newhauser
- The University of Texas at Houston Graduate School of Biomedical Sciences, 6767 Bertner Avenue, S3.8344, Houston, TX 77030, USA
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, TX 77030, USA
| | - X. Ronald Zhu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, TX 77030, USA
| | - Andrew K. Lee
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Rajat J. Kudchadker
- The University of Texas at Houston Graduate School of Biomedical Sciences, 6767 Bertner Avenue, S3.8344, Houston, TX 77030, USA
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, TX 77030, USA
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Cheung J, Kudchadker RJ, Zhu XR, Lee AK, Newhauser WD. Dose perturbations and image artifacts caused by carbon-coated ceramic and stainless steel fiducials used in proton therapy for prostate cancer. Phys Med Biol 2010; 55:7135-47. [PMID: 21076190 DOI: 10.1088/0031-9155/55/23/s13] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Image-guided radiation therapy using implanted fiducial markers is a common solution for prostate localization to improve targeting accuracy. However, fiducials that are typically used for conventional photon radiotherapy cause large dose perturbations in patients who receive proton radiotherapy. A proposed solution has been to use fiducials of lower atomic number (Z) materials to minimize this effect in tissue, but the effects of these fiducials on dose distributions have not been quantified. The objective of this study was to analyze the magnitude of the dose perturbations caused by select lower-Z fiducials (a carbon-coated zirconium dioxide fiducial and a plastic-coated stainless steel fiducial) and compare them to perturbations caused by conventional gold fiducials. Sets of phantoms were used to assess select components of the effects on dose. First, the fiducials were assessed for radiographic visibility using both conventional computed tomography (CT) and an on-board kilovoltage imaging device at our proton therapy center. CT streak artifacts from the fiducials were also measured in a separate phantom. Second, dose perturbations were measured downstream of the fiducials using radiochromic film. The magnitude of dose perturbation was characterized as a function of marker material, implantation depth and orientation with respect to the beam axis. The radiographic visibility of the markers was deemed to be acceptable for clinical use. The dose measurements showed that the perpendicularly oriented zirconium dioxide and stainless steel fiducials located near the center of modulation of the proton beam perturbed the dose by less than 10%, but that the same fiducials in a parallel orientation near the end of the range of the beam could perturb the dose by as much as 38%. This suggests that carbon-coated and stainless steel fiducials could be used in proton therapy if they are located far from the end of the range of the beam and if they are oriented perpendicular to the beam axis.
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Affiliation(s)
- Joey Cheung
- The University of Texas at Houston Graduate School of Biomedical Sciences, Houston, TX 77030, USA
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Herrmann R, Carl J, Jäkel O, Bassler N, Petersen JBB. Investigation of the dosimetric impact of a Ni-Ti fiducial marker in carbon ion and proton beams. Acta Oncol 2010; 49:1160-4. [PMID: 20831508 DOI: 10.3109/0284186x.2010.505934] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
INTRODUCTION Fiducial markers based on a removable stent are currently used in image guided radiotherapy. Here it is investigated what the possible dosimetric impact of such a marker could be, if used in proton or carbon ion treatment. MATERIAL AND METHODS The simulations have been done using the Monte Carlo particle transport code FLUKA with its default hadron therapy settings. A 3 cm long stent is approximated in FLUKA by stacking hollow tori. To simulate realistic clinical conditions a field 5 × 5 cm has been used, delivering a 5 cm wide spread out Bragg peak located 5 cm deep for protons and carbon ions. For protons fields mimicking active and passive beam delivery have been investigated. The stent has been arranged perpendicular, turned 45 degrees, and parallel to the beam axis. RESULTS The position of the 95% dose level shifts for carbon ions 7 mm in proximal direction for the marker perpendicular to the beam and 8 mm if the stent is turned 45 degree for a 1 × 1 cm dose binning on the centre beam axis. For the case where the stent was parallel to beam direction the 95% dose level shifts 26 mm. For active delivered protons, the shift of the 95% dose level is less. The shift for a perpendicular arranged marker is 6 mm, for 45 degrees turned it is 7 mm. For the case where the stent was oriented parallel to the beam, the observed shift is 21 mm. Dose inhomogeneities caused by straggling effects occur only near the distal edge of the field. CONCLUSIONS The results of our investigations show that the Ni-Ti marker has a non negligible impact on the dose distributions for the used radiation types. However if the treatment plan rules out narrow angles between symmetry axis of the stent and the beam direction, this may be compensated.
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Affiliation(s)
- Rochus Herrmann
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Denmark.
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