1
|
van Wagenberg T, Voncken R, van Beveren C, Berbee M, van Limbergen E, Verhaegen F, Paiva Fonseca G. Time-resolved clinical dose volume metrics, calculations and predictions based on source tracking measurements and uncertainties to aid treatment verification and error detection for HDR brachytherapy-a proof-of-principle study. Phys Med Biol 2024; 69:135006. [PMID: 38870948 DOI: 10.1088/1361-6560/ad580e] [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: 02/29/2024] [Accepted: 06/13/2024] [Indexed: 06/15/2024]
Abstract
Objective.High-dose-rate (HDR) brachytherapy lacks routinely available treatment verification methods. Real-time tracking of the radiation source during HDR brachytherapy can enhance treatment verification capabilities. Recent developments in source tracking allow for measurement of dwell times and source positions with high accuracy. However, more clinically relevant information, such as dose discrepancies, is still needed. To address this, a real-time dose calculation implementation was developed to provide more relevant information from source tracking data. A proof-of-principle of the developed tool was shown using source tracking data obtained from a 3D-printed anthropomorphic phantom.Approach.Software was developed to calculate dose-volume-histograms (DVH) and clinical dose metrics from experimental HDR prostate treatment source tracking data, measured in a realistic pelvic phantom. Uncertainty estimation was performed using repeat measurements to assess the inherent dose measuring uncertainty of thein vivodosimetry (IVD) system. Using a novel approach, the measurement uncertainty can be incorporated in the dose calculation, and used for evaluation of cumulative dose and clinical dose-volume metrics after every dwell position, enabling real-time treatment verification.Main results.The dose calculated from source tracking measurements aligned with the generated uncertainty bands, validating the approach. Simulated shifts of 3 mm in 5/17 needles in a single plan caused DVH deviations beyond the uncertainty bands, indicating errors occurred during treatment. Clinical dose-volume metrics could be monitored in a time-resolved approach, enabling early detection of treatment plan deviations and prediction of their impact on the final dose that will be delivered in real-time.Significance.Integrating dose calculation with source tracking enhances the clinical relevance of IVD methods. Phantom measurements show that the developed tool aids in tracking treatment progress, detecting errors in real-time and post-treatment evaluation. In addition, it could be used to define patient-specific action limits and error thresholds, while taking the uncertainty of the measurement system into consideration.
Collapse
Affiliation(s)
- Teun van Wagenberg
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Robert Voncken
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Celine van Beveren
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Maaike Berbee
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Evert van Limbergen
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Frank Verhaegen
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Gabriel Paiva Fonseca
- Department of Radiation Oncology (Maastro), GROW-Research Institute for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| |
Collapse
|
2
|
Wang L, Ding Y, Bruno TL, Stafford RJ, Lin E, Bathala TK, Sanders JW, Ning MS, Ma J, Klopp AH, Venkatesan A, Wang J, Martirosyan KS, Frank SJ. A Novel Positive-Contrast Magnetic Resonance Imaging Line Marker for High-Dose-Rate (HDR) MRI-Assisted Radiosurgery (MARS). Cancers (Basel) 2024; 16:1922. [PMID: 38792000 PMCID: PMC11119838 DOI: 10.3390/cancers16101922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/15/2024] [Accepted: 05/17/2024] [Indexed: 05/26/2024] Open
Abstract
Magnetic resonance imaging (MRI) can facilitate accurate organ delineation and optimal dose distributions in high-dose-rate (HDR) MRI-Assisted Radiosurgery (MARS). Its use for this purpose has been limited by the lack of positive-contrast MRI markers that can clearly delineate the lumen of the HDR applicator and precisely show the path of the HDR source on T1- and T2-weighted MRI sequences. We investigated a novel MRI positive-contrast HDR brachytherapy or interventional radiotherapy line marker, C4:S, consisting of C4 (visible on T1-weighted images) complexed with saline. Longitudinal relaxation time (T1) and transverse relaxation time (T2) for C4:S were measured on a 1.5 T MRI scanner. High-density polyethylene (HDPE) tubing filled with C4:S as an HDR brachytherapy line marker was tested for visibility on T1- and T2-weighted MRI sequences in a tissue-equivalent female ultrasound training pelvis phantom. Relaxivity measurements indicated that C4:S solution had good T1-weighted contrast (relative to oil [fat] signal intensity) and good T2-weighted contrast (relative to water signal intensity) at both room temperature (relaxivity ratio > 1; r2/r1 = 1.43) and body temperature (relaxivity ratio > 1; r2/r1 = 1.38). These measurements were verified by the positive visualization of the C4:S (C4/saline 50:50) HDPE tube HDR brachytherapy line marker on both T1- and T2-weighted MRI sequences. Orientation did not affect the relaxivity of the C4:S contrast solution. C4:S encapsulated in HDPE tubing can be visualized as a positive line marker on both T1- and T2-weighted MRI sequences. MRI-guided HDR planning may be possible with these novel line markers for HDR MARS for several types of cancer.
Collapse
Affiliation(s)
- Li Wang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.W.); (E.L.)
| | - Yao Ding
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (Y.D.); (J.W.)
| | - Teresa L. Bruno
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.L.B.); (M.S.N.); (A.H.K.)
| | - R. Jason Stafford
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (R.J.S.); (J.M.)
| | - Eric Lin
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (L.W.); (E.L.)
| | - Tharakeswara K. Bathala
- Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.K.B.); (A.V.)
| | | | - Matthew S. Ning
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.L.B.); (M.S.N.); (A.H.K.)
| | - Jingfei Ma
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (R.J.S.); (J.M.)
| | - Ann H. Klopp
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.L.B.); (M.S.N.); (A.H.K.)
| | - Aradhana Venkatesan
- Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.K.B.); (A.V.)
| | - Jihong Wang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (Y.D.); (J.W.)
| | - Karen S. Martirosyan
- Department of Physics, The University of Texas Rio Grande Valley, Brownsville, TX 78500, USA;
| | - Steven J. Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; (T.L.B.); (M.S.N.); (A.H.K.)
| |
Collapse
|
3
|
Oh G, Lee J, Kim H, Kim W, Kang S, Chung J, Jeong S, Lee H, Yoon M, Lee B. Monte Carlo simulation study of an in vivo four-dimensional tracking system with a diverging collimator for monitoring radiation source (Ir-192) location during brachytherapy: proof of concept and feasibility. Front Physiol 2024; 15:1302301. [PMID: 38590693 PMCID: PMC10999580 DOI: 10.3389/fphys.2024.1302301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 01/09/2024] [Indexed: 04/10/2024] Open
Abstract
Introduction: The aim of this study was to demonstrate the potential of an in vivo four-dimensional (4D) tracking system to accurately localize the radiation source, Iridium-192 (Ir-192) in high-dose rate brachytherapy. Methods: To achieve time-dependent 3D positioning of the Ir-192 source, we devised a 4D tracking system employing multiple compact detectors. During the system's design phase, we conducted comprehensive optimization and analytical evaluations of the diverging collimator employed for detection purposes. Subsequently, we executed 3D reconstruction and positioning procedures based on the 2D images obtained by six detectors, each equipped with an optimized diverging collimator. All simulations for designing and evaluating the 4D tracking system were performed using the open-source GATE (v9.1) Monte Carlo platform based on the GEANT4 (v10.7) toolkit. In addition, to evaluate the accuracy of the proposed 4D tracking system, we conducted simulations and 3D positioning using a solid phantom and patient data. Finally, the error between the reconstructed position coordinates determined by the tracking system and the original coordinates of the Ir-192 radiation source was analyzed. Results: The parameters for the optimized diverging collimator were a septal thickness of 0.3 mm and a collimator height of 30 mm. A tracking system comprising 6 compact detectors was designed and implemented utilizing this collimator. Analysis of the accuracy of the proposed Ir-192 source tracking system found that the average of the absolute values of the error between the 3D reconstructed and original positions for the simulation with the solid phantom were 0.440 mm for the x coordinate, 0.423 mm for the y coordinate, and 0.764 mm for the z coordinate, and the average Euclidean distance was 1.146 mm. Finally, in a simulation based on data from a patient who underwent brachytherapy, the average Euclidean distance between the original and reconstructed source position was 0.586 mm. Discussion: These results indicated that the newly designed in vivo 4D tracking system for monitoring the Ir-192 source during brachytherapy could determine the 3D position of the radiation source in real time during treatment. We conclude that the proposed positioning system has the potential to make brachytherapy more accurate and reliable.
Collapse
Affiliation(s)
- Geon Oh
- Department of Bioengineering, College of Health Sciences, Korea University, Seoul, Republic of Korea
- Department of Radiation Oncology, Inha University Hospital, Incheon, Republic of Korea
| | - Jeongshim Lee
- Department of Radiation Oncology, Inha University Hospital, Incheon, Republic of Korea
| | - Hunjung Kim
- Department of Radiation Oncology, Inha University Hospital, Incheon, Republic of Korea
| | - Woochul Kim
- Department of Radiation Oncology, Inha University Hospital, Incheon, Republic of Korea
| | - Sangwon Kang
- Department of Radiation Oncology, Seoul National University Bundang Hospital, Seongnam, Gyeonggi, Republic of Korea
| | - Jinbeom Chung
- Department of Radiation Oncology, Seoul National University Bundang Hospital, Seongnam, Gyeonggi, Republic of Korea
| | - Seonghoon Jeong
- Department of Neurology, Inje University Ilsan Paik Hospital, Goyang, Gyeonggi, Republic of Korea
| | - Hakjae Lee
- ARALE Laboratory Co., Ltd., Seoul, Republic of Korea
| | - Myonggeun Yoon
- Department of Bioengineering, College of Health Sciences, Korea University, Seoul, Republic of Korea
| | - Boram Lee
- Department of Radiation Oncology, Inha University Hospital, Incheon, Republic of Korea
| |
Collapse
|
4
|
Bui TNH, Large M, Poder J, Bucci J, Bianco E, Giampaolo RA, Rivetti A, Da Rocha Rolo M, Pastuovic Z, Corradino T, Pancheri L, Petasecca M. Preliminary Characterization of an Active CMOS Pad Detector for Tracking and Dosimetry in HDR Brachytherapy. SENSORS (BASEL, SWITZERLAND) 2024; 24:692. [PMID: 38276383 PMCID: PMC10818778 DOI: 10.3390/s24020692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/15/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024]
Abstract
We assessed the accuracy of a prototype radiation detector with a built in CMOS amplifier for use in dosimetry for high dose rate brachytherapy. The detectors were fabricated on two substrates of epitaxial high resistivity silicon. The radiation detection performance of prototypes has been tested by ion beam induced charge (IBIC) microscopy using a 5.5 MeV alpha particle microbeam. We also carried out the HDR Ir-192 radiation source tracking at different depths and angular dose dependence in a water equivalent phantom. The detectors show sensitivities spanning from (5.8 ± 0.021) × 10-8 to (3.6 ± 0.14) × 10-8 nC Gy-1 mCi-1 mm-2. The depth variation of the dose is within 5% with that calculated by TG-43. Higher discrepancies are recorded for 2 mm and 7 mm depths due to the scattering of secondary particles and the perturbation of the radiation field induced in the ceramic/golden package. Dwell positions and dwell time are reconstructed within ±1 mm and 20 ms, respectively. The prototype detectors provide an unprecedented sensitivity thanks to its monolithic amplification stage. Future investigation of this technology will include the optimisation of the packaging technique.
Collapse
Affiliation(s)
- Thi Ngoc Hang Bui
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia; (T.N.H.B.); (M.L.); (J.P.); (J.B.)
| | - Matthew Large
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia; (T.N.H.B.); (M.L.); (J.P.); (J.B.)
| | - Joel Poder
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia; (T.N.H.B.); (M.L.); (J.P.); (J.B.)
- St George Cancer Care Centre, Kogarah, NSW 2217, Australia
- School of Physics, University of Sydney, Camperdown, NSW 2050, Australia
| | - Joseph Bucci
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia; (T.N.H.B.); (M.L.); (J.P.); (J.B.)
- St George Cancer Care Centre, Kogarah, NSW 2217, Australia
| | - Edoardo Bianco
- Department of Electronics and Telecommunications, Polytechnic University of Turin, 10129 Turin, Italy; (E.B.); (R.A.G.)
- Istituto Nazionale di Fisica Nucleare—Section of Turin, 10125 Turin, Italy; (A.R.); (M.D.R.R.)
| | - Raffaele Aaron Giampaolo
- Department of Electronics and Telecommunications, Polytechnic University of Turin, 10129 Turin, Italy; (E.B.); (R.A.G.)
- Istituto Nazionale di Fisica Nucleare—Section of Turin, 10125 Turin, Italy; (A.R.); (M.D.R.R.)
| | - Angelo Rivetti
- Istituto Nazionale di Fisica Nucleare—Section of Turin, 10125 Turin, Italy; (A.R.); (M.D.R.R.)
| | - Manuel Da Rocha Rolo
- Istituto Nazionale di Fisica Nucleare—Section of Turin, 10125 Turin, Italy; (A.R.); (M.D.R.R.)
| | - Zeljko Pastuovic
- Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia;
| | - Thomas Corradino
- Department of Industrial Engineering, University of Trento, 38123 Trento, Italy (L.P.)
- Trento Institute for Fundamental Physics and Applications, Istituto Nazionale di Fisica Nucleare, 38123 Trento, Italy
| | - Lucio Pancheri
- Department of Industrial Engineering, University of Trento, 38123 Trento, Italy (L.P.)
- Trento Institute for Fundamental Physics and Applications, Istituto Nazionale di Fisica Nucleare, 38123 Trento, Italy
| | - Marco Petasecca
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia; (T.N.H.B.); (M.L.); (J.P.); (J.B.)
| |
Collapse
|
5
|
Nakanishi K, Yamamoto S, Yabe T, Yogo K, Noguchi Y, Okudaira K, Kawachi N, Kataoka J. Estimating blurless and noise-free Ir-192 source images from gamma camera images for high-dose-rate brachytherapy using a deep-learning approach. Biomed Phys Eng Express 2023; 10:015006. [PMID: 37948761 DOI: 10.1088/2057-1976/ad0bb2] [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: 10/03/2023] [Accepted: 11/10/2023] [Indexed: 11/12/2023]
Abstract
Objective. Precise monitoring of the position and dwell time of iridium-192 (Ir-192) during high-dose-rate (HDR) brachytherapy is crucial to avoid serious damage to normal tissues. Source imaging using a compact gamma camera is a potential approach for monitoring. However, images from the gamma camera are affected by blurring and statistical noise, which impact the accuracy of source position monitoring. This study aimed to develop a deep-learning approach for estimating ideal source images that reduce the effect of blurring and statistical noise from experimental images captured using a compact gamma camera.Approach. A double pix2pix model was trained using the simulated gamma camera images of an Ir-192 source. The first model was responsible for denoising the Ir-192 images, whereas the second model performed super resolution. Trained models were then applied to the experimental images to estimate the ideal images.Main results. At a distance of 100 mm between the compact gamma camera and the Ir-192 source, the difference in full width at half maximum (FWHM) between the estimated and actual source sizes was approximately 0.5 mm for a measurement time of 1.5 s. This difference has been improved from approximately 2.7 mm without the use of DL. Even with a measurement time of 0.1 s, the ideal images could be estimated as accurately as in the 1.5 s measurements. This method consistently achieved accurate estimations of the source images at any position within the field of view; however, the difference increased with the distance between the Ir-192 source and the compact gamma camera.Significance. The proposed method successfully provided estimated images from the experimental images within errors smaller than 0.5 mm at 100 mm. This method is promising for reducing blurring and statistical noise from the experimental images, enabling precise real-time monitoring of Ir-192 sources during HDR brachytherapy.
Collapse
Affiliation(s)
- Kohei Nakanishi
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Japan
| | | | - Takuya Yabe
- Takasaki Institute for Advanced Quantum Science, Foundational Quantum Technology Research Directorate, National Institutes for Quantum Science and Technology (QST), Japan
| | - Katsunori Yogo
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Japan
| | - Yumiko Noguchi
- Department of Radiological Technology, Nagoya University Hospital, Japan
| | - Kuniyasu Okudaira
- Department of Radiological Technology, Nagoya University Hospital, Japan
| | - Naoki Kawachi
- Takasaki Institute for Advanced Quantum Science, Foundational Quantum Technology Research Directorate, National Institutes for Quantum Science and Technology (QST), Japan
| | - Jun Kataoka
- Faculty of Science and Engineering, Waseda University, Japan
| |
Collapse
|
6
|
Sung S, Lee M, Choi HJ, Park H, Cheon BW, Min CH, Yeom YS, Kim H, You SH, Choi HJ. Feasibility of internal-source tracking with C-arm CT/SPECT imaging with limited-angle projection data for online in vivo dose verification in brachytherapy: A Monte Carlo simulation study. Brachytherapy 2023; 22:673-685. [PMID: 37301703 DOI: 10.1016/j.brachy.2023.05.003] [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: 10/01/2022] [Revised: 03/13/2023] [Accepted: 05/07/2023] [Indexed: 06/12/2023]
Abstract
PURPOSE The current protocol for use of the image-guided adaptive brachytherapy (IGABT) procedure entails transport of a patient between the treatment room and the 3-D tomographic imaging room after implantation of the applicators in the body, which movement can cause position displacement of the applicator. Moreover, it is not possible to track 3-D radioactive source movement inside the body, even though there can be significant inter- and intra-fractional patient-setup changes. In this paper, therefore, we propose an online single-photon emission computed tomography (SPECT) imaging technique with a combined C-arm fluoroscopy X-ray system and attachable parallel-hole collimator for internal radioactive source tracking of every source position in the applicator. METHODS AND MATERIALS In the present study, using Geant4 Monte Carlo (MC) simulation, the feasibility of high-energy gamma detection with a flat-panel detector for X-ray imaging was assessed. Further, a parallel-hole collimator geometry was designed based on an evaluation of projection image quality for a 192Ir point source, and 3-D limited-angle SPECT-image-based source-tracking performances were evaluated for various source intensities and positions. RESULTS The detector module attached to the collimator could discriminate the 192Ir point source with about 3.4% detection efficiency when including the total counts in the entire deposited energy region. As the result of collimator optimization, hole size, thickness, and length were determined to be 0.5, 0.2, and 45 mm, respectively. Accordingly, the source intensities and positions also were successfully tracked with the 3-D SPECT imaging system when the C-arm was rotated within 110° in 2 seconds. CONCLUSIONS We expect that this system can be effectively implemented for online IGABT and in vivo patient dose verification.
Collapse
Affiliation(s)
- Saerom Sung
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Minjae Lee
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Hyung-Joo Choi
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Hyojun Park
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Bo-Wi Cheon
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Chul Hee Min
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Yeon Soo Yeom
- Department of Radiation Convergence Engineering, Yonsei University, Wonju-si, Gangwon-do, Republic of Korea
| | - Hyemi Kim
- Department of Radiation Oncology, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju-si, Gangwon-do, Republic of Korea
| | - Sei Hwan You
- Department of Radiation Oncology, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju-si, Gangwon-do, Republic of Korea
| | - Hyun Joon Choi
- Department of Radiation Oncology, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju-si, Gangwon-do, Republic of Korea.
| |
Collapse
|
7
|
Seo J, Lee H, Hwan Ahn S, Yoon M. Feasibility study of a scintillation sheet-based detector for fluence monitoring during external photon beam radiotherapy. Phys Med 2023; 112:102628. [PMID: 37354806 DOI: 10.1016/j.ejmp.2023.102628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 03/24/2023] [Accepted: 06/13/2023] [Indexed: 06/26/2023] Open
Abstract
PURPOSE This study evaluated the properties of a scintillation sheet-based dosimetry system for beam monitoring with high spatial resolution, including the effects of this system on the treatment beam. The dosimetric characteristics and feasibility of this system for clinical use were also evaluated. METHODS The effects of the dosimetry system on the beam were evaluated by measuring the percentage depth doses, dose profiles, and transmission factors. Fifteen treatment plans were created, and the influence of the dosimetry system on these clinical treatment plans was evaluated. The performance of the system was assessed by determining signal linearity, dose rate dependence, and reproducibility. The feasibility of the system for clinical use was evaluated by comparing intensity distributions with reference intensity distributions verified by quality assurance. RESULTS The spatial resolution of the dosimetry system was found to be 0.43 mm/pixel when projected to the isocenter plane. The dosimetry system attenuated the intensity of 6 MV beams by about 1.1%, without affecting the percentage depth doses and dose profiles. The response of the dosimetry system was linear, independent of the dose rate used in the clinic, and reproducible. Comparison of intensity distributions of evaluation treatment fields with reference intensity distributions showed that the 1%/1 mm average gamma passing rate was 99.6%. CONCLUSIONS The dosimetry system did not significantly alter the beam characteristics, indicating that the system could be implemented by using only a transmission factor. The dosimetry system is clinically suitable for monitoring treatment beam delivery with higher spatial resolution than other transmission detectors.
Collapse
Affiliation(s)
- Jaehyeon Seo
- Department of Bio-Convergence Engineering, Korea University, Seoul, Republic of Korea; Environmental Radioactivity Assessment Team, Korea Atomic Energy Research Institute, Daejeon, Republic of Korea
| | - Hyunho Lee
- Department of Bio-Convergence Engineering, Korea University, Seoul, Republic of Korea; Department of Radiation Oncology, Samsung Medical Center, Seoul, Republic of Korea
| | - Sung Hwan Ahn
- Department of Radiation Oncology, Samsung Medical Center, Seoul, Republic of Korea.
| | - Myonggeun Yoon
- Department of Bio-Convergence Engineering, Korea University, Seoul, Republic of Korea; FieldCure Ltd, Seoul, Republic of Korea.
| |
Collapse
|
8
|
van Wagenberg T, Fonseca GP, Voncken R, van Beveren C, van Limbergen E, Lutgens L, Vanneste BGL, Berbee M, Reniers B, Verhaegen F. Treatment verification in high dose rate brachytherapy using a realistic 3D printed head phantom and an imaging panel. Brachytherapy 2023; 22:269-278. [PMID: 36631373 DOI: 10.1016/j.brachy.2022.11.012] [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: 06/15/2022] [Revised: 10/24/2022] [Accepted: 11/26/2022] [Indexed: 01/11/2023]
Abstract
PURPOSE Even though High Dose Rate (HDR) brachytherapy has good treatment outcomes in different treatment sites, treatment verification is far from widely implemented because of a lack of easily available solutions. Previously it has been shown that an imaging panel (IP) near the patient can be used to determine treatment parameters such as the dwell time and source positions in a single material pelvic phantom. In this study we will use a heterogeneous head phantom to test this IP approach, and simulate common treatment errors to assess the sensitivity and specificity of the error-detecting capabilities of the IP. METHODS AND MATERIALS A heterogeneous head-phantom consisting of soft tissue and bone equivalent materials was 3D-printed to simulate a base of tongue treatment. An High Dose Rate treatment plan with 3 different catheters was used to simulate a treatment delivery, using dwell times ranging from 0.3 s to 4 s and inter-dwell distances of 2 mm. The IP was used to measure dwell times, positions and detect simulated errors. Measured dwell times and positions were used to calculate the delivered dose. RESULTS Dwell times could be determined within 0.1 s. Source positions were measured with submillimeter accuracy in the plane of the IP, and average distance accuracy of 1.7 mm in three dimensions. All simulated treatment errors (catheter swap, catheter shift, afterloader errors) were detected. Dose calculations show slightly different distributions with the measured dwell positions and dwell times (gamma pass rate for 1 mm/1% of 96.5%). CONCLUSIONS Using an IP, it was possible to verify the treatment in a realistic heterogeneous phantom and detect certain treatment errors.
Collapse
Affiliation(s)
- Teun van Wagenberg
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Gabriel Paiva Fonseca
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Robert Voncken
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Celine van Beveren
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Evert van Limbergen
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Ludy Lutgens
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Ben G L Vanneste
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands; Department of Human Structure and Repair; Department of Radiation Oncology, Ghent University Hospital, Gent, Belgium
| | - Maaike Berbee
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Brigitte Reniers
- Research group NuTeC, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Frank Verhaegen
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Reproduction, Maastricht University Medical Centre+, Maastricht, The Netherlands.
| |
Collapse
|
9
|
Nagata J, Yamamoto S, Yabe T, Yogo K, Nakanishi K, Noguchi Y, Okudaira K, Kamada K, Yoshikawa A, Kataoka J. Technical note: Short-time sequential high-energy gamma photon imaging using list-mode data acquisition system for high-dose-rate brachytherapy. Med Phys 2022; 49:7703-7714. [PMID: 36063027 DOI: 10.1002/mp.15957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 07/28/2022] [Accepted: 08/16/2022] [Indexed: 12/27/2022] Open
Abstract
PURPOSE Measurement of the dwell time and moving speed of a high-activity iridium-192 (Ir-192) source used for high-dose-rate (HDR) brachytherapy is important for estimating the precise dose delivery to a tumor. For this purpose, we used a cerium-doped yttrium aluminum perovskite (YA1O3 :YAP(Ce)) gamma camera system, combined with a list-mode data acquisition system that can acquire short-time sequential images, and measured the dwell times and moving speeds of the Ir-192 source. METHODS Gamma photon imaging was conducted using the gamma camera in list mode for the Ir-192 source of HDR brachytherapy with fixed dwell times and positions. The acquired list-mode images were sorted to millisecond-order interval time sequential images to evaluate the dwell time at each position. Time count rate curves were derived to calculate the dwell time at each source position and moving speed of the source. RESULTS We could measure the millisecond-order time sequential images for the Ir-192 source. The measured times for the preset dwell times of 2 s and 10 s were 1.98 to 2.00 s full width at half maximum (FWHM) and 10.0 s FWHM, respectively. The dwell times at the first dwell position were larger than those at other positions. We also measured the moving speeds of the source after the dwells while moving back to the afterloader and found the speed increased with the distance from the edge of the field of view to the last dwell position. CONCLUSION We conclude that millisecond-order time sequential imaging of the Ir-192 source is possible by using a gamma camera and is useful for evaluating the dwell times and moving speeds of the Ir-192 source.
Collapse
Affiliation(s)
- Jura Nagata
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Seiichi Yamamoto
- Faculty of Science and Engineering, Waseda University, Tokyo, Japan
| | - Takuya Yabe
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Katsunori Yogo
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kohei Nakanishi
- Department of Integrated Health Science, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yumiko Noguchi
- Department of Radiological Technology, Nagoya University Hospital, Nagoya, Japan
| | - Kuniyasu Okudaira
- Department of Radiological Technology, Nagoya University Hospital, Nagoya, Japan
| | - Kei Kamada
- New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai, Japan
| | - Akira Yoshikawa
- New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai, Japan
| | - Jun Kataoka
- Faculty of Science and Engineering, Waseda University, Tokyo, Japan
| |
Collapse
|
10
|
Melhus CS, Simiele SJ, Aima M, Richardson S. Learning from the past: a century of accuracy, aspirations, and aspersions in brachytherapy. Br J Radiol 2022; 95:20220500. [PMID: 35969474 PMCID: PMC9733622 DOI: 10.1259/bjr.20220500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 11/05/2022] Open
Abstract
The oldest form of radiation therapy, brachytherapy, has been investigated and reported in the scientific and medical literature for well over a century. Known by many names over the years, radium-based, empirical practices evolved over decades to contemporary practice. This includes treatment at various dose rates using multiple radionuclides or even electrically generated photon sources. Predictions or prognostications of what may happen in the future enjoy a history that spans centuries, e.g. those by Nostradamus in the 1500s. In this review article, publications from several eras of past practice between the early 1900s and the late 2010s where the authors address the "future of brachytherapy" are presented, and for many of these publications, one can use the benefit of the intervening years to comment on the accuracy or the inaccuracies inherent in those publications. Finally, recently published papers are reviewed to examine current expectations for the future practice of brachytherapy.
Collapse
Affiliation(s)
- Christopher S Melhus
- Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts
| | - Samantha J Simiele
- Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Manik Aima
- Department of Radiation Oncology, Stanford University, Stanford, California, United States
| | - Susan Richardson
- Department of Radiation Oncology, Swedish Medical Center, Seattle, Washington, United States
| |
Collapse
|
11
|
Optimization of the energy window setting in Ir-192 source imaging for high-dose-rate brachytherapy using a YAP(Ce) gamma camera. Phys Med 2022; 103:66-73. [DOI: 10.1016/j.ejmp.2022.09.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/19/2022] Open
|
12
|
Lekatou A, Peppa V, Karaiskos P, Pantelis E, Papagiannis P. On the potential of 2D ion chamber arrays for high-dose rate remote afterloading brachytherapy quality assurance. Phys Med Biol 2022; 67. [PMID: 35334474 DOI: 10.1088/1361-6560/ac612d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 03/25/2022] [Indexed: 01/08/2023]
Abstract
Objective. To investigate the potential of 2D ion chamber arrays to serve as a standalone tool for the verification of source strength, positioning and dwell time, within the framework of192Ir high-dose rate brachytherapy device quality assurance (QA).Approach.A commercially available ion chamber array was used. Fitting of a 2D Lorentzian peak function to experimental data from a multiple source dwell position irradiation on a frame-by-frame basis, facilitated tracking of the source center orthogonal projection on the array plane. For source air kerma strength verification, Monte Carlo simulation was employed to obtain a chamber array- and source-specific correction factor of calibration with a 6 MV photon beam. This factor converted the signal measured by each ion chamber element to air kerma in free space. A source positioning correction was also applied to lift potential geometry mismatch between experiment and Monte Carlo simulation.Main results.Spatial and temporal accuracy of source movement was verified within 0.5 mm and 0.02 s, respectively, in compliance with the test endpoints recommended by international professional societies. The source air kerma strength was verified experimentally within method uncertainties estimated as 1.44% (k = 1). The source positioning correction method employed did not introduce bias to experimental results of irradiations where source positioning was accurate. Development of a custom jig attachable to the chamber array for accurate and reproducible experimental set up would improve testing accuracy and obviate the need for source positioning correction in air kerma strength verification.Significance.Delivery of a single irradiation plan, optimized based on results of this work, to a 2D ion chamber array can be used for concurrent testing of source position, dwell time and air kerma strength, and the procedure can be expedited through automation. Chamber arrays merit further study in treatment planning QA and real time,in vivodose verification.
Collapse
Affiliation(s)
- Aristea Lekatou
- Medical Physics Laboratory, Department of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - Vasiliki Peppa
- Medical Physics Laboratory, Department of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - Pantelis Karaiskos
- Medical Physics Laboratory, Department of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - Evangelos Pantelis
- Medical Physics Laboratory, Department of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| | - Panagiotis Papagiannis
- Medical Physics Laboratory, Department of Medicine, National and Kapodistrian University of Athens, 75 Mikras Asias, 11527 Athens, Greece
| |
Collapse
|
13
|
Hanlon MD, Smith RL, Franich RD. MaxiCalc: A tool for online dosimetric evaluation of source-tracking based treatment verification in HDR brachytherapy. Phys Med 2022; 94:58-64. [PMID: 34998133 DOI: 10.1016/j.ejmp.2021.12.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 12/09/2021] [Accepted: 12/16/2021] [Indexed: 01/11/2023] Open
Abstract
PURPOSE Source tracking is becoming a more widely used approach in HDR brachytherapy treatment verification. While it provides a sensitive method to detect deviations from the treatment plan during delivery, it does not show the clinical significance of any detected changes. By incorporating a tool that calculates volumetric doses and DVH indices from measurements, source tracking systems can be expanded to assess dosimetric significance of any deviations from the plan. METHODS The source tracking dose calculation tool, MaxiCalc, was developed in MATLAB. Validation was performed by comparing doses and DVH indices calculated in MaxiCalc to those calculated by the clinical TPS, for several test plans and 10 clinical plans. Clinical implementation was demonstrated by calculating volumetric doses from a clinical source tracking event. RESULTS MaxiCalc showed excellent agreement with the clinical TPS for point and volumetric doses (mean difference < 0.01% and 0.1% respectively). MaxiCalc calculates dosimetrically equivalent plans to the TPS with agreement < 0.3% for all DVH indices except PTV V200%. Small differences seen for the clinical source tracking event were consistent with the known tracking uncertainties enabling them to be quantified for clinical decision making. Calculations are fast, enabling real-time use. CONCLUSIONS MaxiCalc is an independent tool that calculates doses and DVH indices from dwells measured with any clinical HDR brachytherapy source tracking system. This extends the capabilities of source tracking systems from determining discrepancies in positions or times during delivery to assessing the dosimetric impact of any detected deviations, allowing for more comprehensive treatment verification and evaluation.
Collapse
Affiliation(s)
- Maximilian D Hanlon
- School of Science, RMIT University, Melbourne, Australia; Alfred Health Radiation Oncology, The Alfred, Melbourne, Australia.
| | - Ryan L Smith
- School of Science, RMIT University, Melbourne, Australia; Alfred Health Radiation Oncology, The Alfred, Melbourne, Australia
| | - Rick D Franich
- School of Science, RMIT University, Melbourne, Australia
| |
Collapse
|
14
|
Jørgensen EB, Johansen JG, Overgaard J, Piché-Meunier D, Tho D, Rosales HML, Tanderup K, Beaulieu L, Kertzscher G, Beddar S. A high-Z inorganic scintillator-based detector for time-resolved in vivo dosimetry during brachytherapy. Med Phys 2021; 48:7382-7398. [PMID: 34586641 DOI: 10.1002/mp.15257] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/08/2021] [Accepted: 09/09/2021] [Indexed: 11/11/2022] Open
Abstract
PURPOSE High-dose rate (HDR) and pulsed-dose rate (PDR) brachytherapy would benefit from an independent treatment verification system to monitor treatment delivery and to detect errors in real time. This paper characterizes and provides an uncertainty budget for a detector based on a fiber-coupled high-Z inorganic scintillator capable of performing time-resolved in vivo dosimetry during HDR and PDR brachytherapy. METHOD The detector was composed of a detector probe and an optical reader. The detector probe consisted of either a 0.5 × 0.4 × 0.4 mm3 (HDR) or a 1.0 × 0.4 × 0.4 mm3 (PDR) cuboid ZnSe:O crystal glued onto an optical-fiber cable. The outer diameter of the detector probes was 1 mm, and fit inside standard brachytherapy catheters. The signal from the detector probe was read out at 20 Hz by a photodiode and a data acquisition device inside the optical reader. In order to construct an uncertainty budget for the detector, six characteristics were determined: (1) temperature dependence of the detector probe, (2) energy dependence as a function of the probe-to-source position in 2D (determined with 2 mm resolution using a robotic arm), (3) the signal-to-noise ratio (SNR), (4) short-term stability over 8 h, and (5) long-term stability of three optical readers and four probes used for in vivo monitoring in HDR and PDR treatments over 21 months (196 treatments and 189 detector calibrations, and (6) dose-rate dependence. RESULTS The total uncertainty of the detector at a 20 mm probe-to-source distance was < 5.1% and < 5.8% for the HDR and PDR versions, respectively. Regarding the above characteristics, (1) the sensitivity of the detector decreased by an average of 1.4%/°C for detector probe temperatures varying from 22 to 37°C; (2) the energy dependence of the detector was nonlinear and depended on both probe-to-source distance and the angle between the probe and the brachytherapy source; (3) the median SNRs were 187 and 34 at a 20 mm probe-to-source distance for the HDR and PDR versions, respectively (corresponding median source activities of 4.8 and 0.56 Ci, respectively); (4) the detector response varied by 0.6% in 11 identical irradiations over 8 h; (5) the sensitivity of the four detector probes decreased systematically by 0-1.2%/100 Gy of dose delivered to the probes, and random fluctuations of 4.8% in the sensitivity were observed for the three probes used in PDR and 1.9% for the probe used in HDR; and (6) the detector response was linear with dose rate. CONCLUSION ZnSe:O detectors can be used effectively for in vivo dosimetry and with high accuracy for HDR and PDR brachytherapy applications.
Collapse
Affiliation(s)
- Erik B Jørgensen
- Health Graduate School, Aarhus University, Aarhus, Denmark.,Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Jacob G Johansen
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Dominique Piché-Meunier
- Département de physique-de génie physique et d'optique et Centre de recherche sur le cancer, Université Laval, Québec City, Quebec, Canada.,Département de radio-oncologie et Axe Oncologie, CHU de Québec-Université Laval, Québec City, Quebec, Canada
| | - Daline Tho
- Département de physique-de génie physique et d'optique et Centre de recherche sur le cancer, Université Laval, Québec City, Quebec, Canada.,Département de radio-oncologie et Axe Oncologie, CHU de Québec-Université Laval, Québec City, Quebec, Canada
| | - Haydee M L Rosales
- Département de physique-de génie physique et d'optique et Centre de recherche sur le cancer, Université Laval, Québec City, Quebec, Canada.,Département de radio-oncologie et Axe Oncologie, CHU de Québec-Université Laval, Québec City, Quebec, Canada
| | - Kari Tanderup
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Luc Beaulieu
- Département de physique-de génie physique et d'optique et Centre de recherche sur le cancer, Université Laval, Québec City, Quebec, Canada.,Département de radio-oncologie et Axe Oncologie, CHU de Québec-Université Laval, Québec City, Quebec, Canada
| | - Gustavo Kertzscher
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark.,Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Sam Beddar
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| |
Collapse
|
15
|
Linares Rosales HM, Johansen JG, Kertzscher G, Tanderup K, Beaulieu L, Beddar S. 3D source tracking and error detection in HDR using two independent scintillator dosimetry systems. Med Phys 2021; 48:2095-2107. [PMID: 33222208 DOI: 10.1002/mp.14607] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/22/2020] [Accepted: 11/01/2020] [Indexed: 01/22/2023] Open
Abstract
PURPOSE The aim of this study is to perform three-dimensional (3D) source position reconstruction by combining in vivo dosimetry measurements from two independent detector systems. METHODS Time-resolved dosimetry was performed in a water phantom during HDR brachytherapy irradiation with 192 Ir source using two detector systems. The first was based on three plastic scintillator detectors and the second on a single inorganic crystal (CsI:Tl). Brachytherapy treatments were simulated in water under TG-43U1 conditions, including a HDR prostate plan. Treatment needles were placed in distances covering a range of source movement of 120 mm around the detectors. The distance from each dwell position to each scintillator was determined based on the measured dose rates. The three distances given by the mPSD were recalculated to a position along the catheter (z) and a distance radially away from the mPSD (xy) for each dwell position (a circumference around the mPSD). The source x, y, and z coordinates were derived from the intersection of the mPSD's circumference with the sphere around the ISD based on the distance to this detector. We evaluated the accuracy of the source position reconstruction as a function of the distance to the source, the most likely location for detector positioning within a prostate volume, as well as the capacity to detect positioning errors. RESULTS Approximately 4000 source dwell positions were tracked for eight different HDR plans. An intersection of the mPSD torus and the ISD sphere was observed in 77.2% of the dwell positions, assuming no uncertainty in the dose rate determined distance. This increased to 100% if 1σ search regions were added. However, only 73(96)% of the expected dwell positions were found within the intersection band for 1(2) σ uncertainties. The agreement between the source's reconstructed and expected positions was within 3 mm for a range of distances to the source up to 50 mm. The experiments on a HDR prostate plan, showed that by having at least one of the detectors located in the middle of the prostate volume, reduces the measurement deviations considerably compared to scenarios where the detectors were located outside of the prostate volume. The analysis showed a detection probability that, in most cases, is far from the random detection threshold. Errors of 1(2) mm can be detected in ranges of 5-25 (25-50) mm from the source, with a true detection probability rate higher than 80%, while the false probability rate is kept below 20%. CONCLUSIONS By combining two detector responses, we enabled the determination of the absolute source coordinates. The combination of the mPSD and the ISD in vivo dosimetry constitutes a promising alternative for real-time 3D source tracking in HDR brachytherapy.
Collapse
Affiliation(s)
| | - Jacob G Johansen
- Department of Oncology, Aarhus University Hospital, Aarhus C, Denmark
| | | | - Kari Tanderup
- Department of Oncology, Aarhus University Hospital, Aarhus C, Denmark
| | - Luc Beaulieu
- CHU de Quebec-Université Laval, Quebec, Canada.,Université Laval, Quebec, Canada
| | - Sam Beddar
- The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
16
|
Aldelaijan S, Devic S, Bekerat H, Papaconstadopoulos P, Schneider J, Seuntjens J, Cormack RA, Buzurovic IM. Positional and angular tracking of HDR 192 Ir source for brachytherapy quality assurance using radiochromic film dosimetry. Med Phys 2020; 47:6122-6139. [PMID: 33064876 DOI: 10.1002/mp.14540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/31/2020] [Accepted: 09/25/2020] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To quantify and verify the dosimetric impact of high-dose rate (HDR) source positional uncertainty in brachytherapy, and to introduce a model for three-dimensional (3D) position tracking of the HDR source based on a two-dimensional (2D) measurement. This model has been utilized for the development of a comprehensive source quality assurance (QA) method using radiochromic film (RCF) dosimetry including assessment of different digitization uncertainties. METHODS An algorithm was developed and verified to generate 2D dose maps of the mHDR-V2 192 Ir source (Elekta, Veenendaal, Netherlands) based on the AAPM TG-43 formalism. The limits of the dosimetric error associated with source (0.9 mm diameter) positional uncertainty were evaluated and experimentally verified with EBT3 film measurements for 6F (2.0 mm diameter) and 4F (1.3 mm diameter) size catheters at the surface (4F, 6F) and 10 mm further (4F only). To quantify this uncertainty, a source tracking model was developed to incorporate the unique geometric features of all isodose lines (IDLs) within any given 2D dose map away from the source. The tracking model normalized the dose map to its maximum, then quantified the IDLs using blob analysis based on features such as area, perimeter, weighted centroid, elliptic orientation, and circularity. The Pearson correlation coefficients (PCCs) between these features and source coordinates (x, y, z, θy , θz ) were calculated. To experimentally verify the accuracy of the tracking model, EBT3 film pieces were positioned within a Solid Water® (SW) phantom above and below the source and they were exposed simultaneously. RESULTS The maximum measured dosimetric variations on the 6F and 4F catheter surfaces were 39.8% and 36.1%, respectively. At 10 mm further, the variation reduced to 2.6% for the 4F catheter which is in agreement with the calculations. The source center (x, y) was strongly correlated with the low IDL-weighted centroid (PCC = 0.99), while the distance to source (z) was correlated with the IDL areas (PCC = 0.96) and perimeters (PCC = 0.99). The source orientation θy was correlated with the difference between high and low IDL-weighted centroids (PCC = 0.98), while θz was correlated with the elliptic orientation of the 60-90% IDLs (PCC = 0.97) for a maximum distance of z = 5 mm. Beyond 5 mm, IDL circularity was significant, therefore limiting the determination of θz (PCC ≤ 0.48). The measured positional errors from the film sets above and below the source indicated a source position at the bottom of the catheter (-0.24 ± 0.07 mm). CONCLUSIONS Isodose line features of a 2D dose map away from the HDR source can reveal its spatial coordinates. RCF was shown to be a suitable dosimeter for source tracking and dosimetry. This technique offers a novel source QA method and has the potential to be used for QA of commercial and customized applicators.
Collapse
Affiliation(s)
- Saad Aldelaijan
- Department of Radiation Oncology, Dana Farber/Brigham and Women's Cancer Center, Harvard Medical School, Boston, MA, 02115, USA.,Department of Biomedical Engineering, Montreal Neurological Institute, McGill University, Montréal, QC, H3A 2B4, Canada.,Medical Physics Unit, McGill University, Montréal, QC, H4A 3J1, Canada.,Department of Radiation Oncology, SMBD Jewish General Hospital, Montréal, QC, H3T 1E2, Canada.,Biomedical Physics Department, King Faisal Specialist Hospital & Research Centre, Riyadh, 12713, Saudi Arabia
| | - Slobodan Devic
- Medical Physics Unit, McGill University, Montréal, QC, H4A 3J1, Canada.,Department of Radiation Oncology, SMBD Jewish General Hospital, Montréal, QC, H3T 1E2, Canada
| | - Hamed Bekerat
- Department of Radiation Oncology, SMBD Jewish General Hospital, Montréal, QC, H3T 1E2, Canada
| | | | - James Schneider
- Department of Radiation Oncology, SMBD Jewish General Hospital, Montréal, QC, H3T 1E2, Canada
| | - Jan Seuntjens
- Medical Physics Unit, McGill University, Montréal, QC, H4A 3J1, Canada
| | - Robert A Cormack
- Department of Radiation Oncology, Dana Farber/Brigham and Women's Cancer Center, Harvard Medical School, Boston, MA, 02115, USA
| | - Ivan M Buzurovic
- Department of Radiation Oncology, Dana Farber/Brigham and Women's Cancer Center, Harvard Medical School, Boston, MA, 02115, USA
| |
Collapse
|
17
|
Fonseca GP, Johansen JG, Smith RL, Beaulieu L, Beddar S, Kertzscher G, Verhaegen F, Tanderup K. In vivo dosimetry in brachytherapy: Requirements and future directions for research, development, and clinical practice. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2020; 16:1-11. [PMID: 33458336 PMCID: PMC7807583 DOI: 10.1016/j.phro.2020.09.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 08/24/2020] [Accepted: 09/17/2020] [Indexed: 12/19/2022]
Abstract
Brachytherapy can deliver high doses to the target while sparing healthy tissues due to its steep dose gradient leading to excellent clinical outcome. Treatment accuracy depends on several manual steps making brachytherapy susceptible to operational mistakes. Currently, treatment delivery verification is not routinely available and has led, in some cases, to systematic errors going unnoticed for years. The brachytherapy community promoted developments in in vivo dosimetry (IVD) through research groups and small companies. Although very few of the systems have been used clinically, it was demonstrated that the likelihood of detecting deviations from the treatment plan increases significantly with time-resolved methods. Time–resolved methods could interrupt a treatment avoiding gross errors which is not possible with time-integrated dosimetry. In addition, lower experimental uncertainties can be achieved by using source-tracking instead of direct dose measurements. However, the detector position in relation to the patient anatomy remains a main source of uncertainty. The next steps towards clinical implementation will require clinical trials and systematic reporting of errors and near-misses. It is of utmost importance for each IVD system that its sensitivity to different types of errors is well understood, so that end-users can select the most suitable method for their needs. This report aims to formulate requirements for the stakeholders (clinics, vendors, and researchers) to facilitate increased clinical use of IVD in brachytherapy. The report focuses on high dose-rate IVD in brachytherapy providing an overview and outlining the need for further development and research.
Collapse
Affiliation(s)
- Gabriel P Fonseca
- Department of Radiation Oncology (Maastro), GROW School for Oncology, Maastricht University Medical Centre+, Maastricht, Doctor Tanslaan 12, 6229 ET Maastricht, the Netherlands
| | - Jacob G Johansen
- Department of Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus, Denmark
| | - Ryan L Smith
- Alfred Health Radiation Oncology, Alfred Health, 55 Commercial Rd, Melbourne, VIC 3004, Australia
| | - Luc Beaulieu
- Department of Physics, Engineering Physics & Optics and Cancer Research Center, Université Laval, Quebec City, QC, Canada.,Department of Radiation Oncology, Research Center of CHU de Québec, Université Laval, Quebec City, QC, Canada
| | - Sam Beddar
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1420, Houston, TX 77030, United States
| | - Gustavo Kertzscher
- Department of Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus, Denmark
| | - Frank Verhaegen
- Department of Radiation Oncology (Maastro), GROW School for Oncology, Maastricht University Medical Centre+, Maastricht, Doctor Tanslaan 12, 6229 ET Maastricht, the Netherlands
| | - Kari Tanderup
- Department of Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus, Denmark
| |
Collapse
|
18
|
Watanabe Y, Maeyama T, Mochizuki A, Mizukami S, Hayashi SI, Terazaki T, Muraishi H, Takei H, Gomi T, Shimono T. Verification of dose distribution in high-dose-rate brachytherapy using a nanoclay-based radio-fluorogenic gel dosimeter. Phys Med Biol 2020; 65:175008. [PMID: 32485693 DOI: 10.1088/1361-6560/ab98d2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Dose distributions have become more complex with the introduction of image-guided brachytherapy in high-dose-rate (HDR) brachytherapy treatments. Therefore, to correctly execute HDR, conducting a quality assurance programme for the remote after-loading system and verifying the dose distribution in the patient treatment plan are necessary. The characteristics of the dose distribution of HDR brachytherapy are that the dose is high near the source and rapidly drops when the distance from the source increases. Therefore, a measurement tool corresponding to the characteristic is required. In this study, using an Iridium-192 (Ir-192) source, we evaluated the basic characteristics of a nanoclay-based radio-fluorogenic gel (NC-RFG) dosimeter that is a fluorescent gel dosimeter using dihydrorhodamine 123 hydrochloride as a fluorescent probe. The two-dimensional dose distribution measurements were performed at multiple source positions to simulate a clinical plan. Fluorescence images of the irradiated NC-RFG were obtained at a high resolution (0.04 mm pixel-1) using a gel scanner with excitation at 465 nm. Good linearity was confirmed up to a dose range of 100 Gy without dose rate dependence. The dose distribution measurement at the five-point source position showed good agreement with the treatment planning system calculation. The pass ratio by gamma analysis was 92.1% with a 2%/1 mm criterion. The NC-RFG dosimeter demonstrates to have the potential of being a useful tool for quality assurance of the dose distribution delivered by HDR brachytherapy. Moreover, compared with conventional gel dosimeters such as polymer gel and Fricke gel dosimeters it solves the problems of diffusion, dose rate dependence and inhibition of oxygen-induced reactions. Furthermore, it facilitates dose data to be read in a short time after irradiation, which is useful for clinical use.
Collapse
Affiliation(s)
- Yusuke Watanabe
- School of Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Clinical utility and value contribution of an MRI-positive line marker for image-guided brachytherapy in gynecologic malignancies. Brachytherapy 2020; 19:305-315. [DOI: 10.1016/j.brachy.2019.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/29/2019] [Accepted: 12/30/2019] [Indexed: 01/19/2023]
|
20
|
Yamamoto S, Yogo K, Noguchi Y, Nakaya T, Okudaira K. Imaging of Ir-192 source using a high energy gamma camera for high-dose-rate brachytherapy. RADIAT MEAS 2019. [DOI: 10.1016/j.radmeas.2019.106128] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
21
|
Johansen J, Kertzscher G, Jørgensen E, Rylander S, Bentzen L, Hokland S, Søndergaard C, With A, Buus S, Tanderup K. Dwell time verification in brachytherapy based on time resolved in vivo dosimetry. Phys Med 2019; 60:156-161. [DOI: 10.1016/j.ejmp.2019.03.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/22/2019] [Accepted: 03/29/2019] [Indexed: 10/27/2022] Open
|