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Shirai K, Aoki S, Endo M, Takahashi Y, Fukuda Y, Akahane K, Musha A, Sato H, Wakatsuki M, Ishikawa H, Sasaki R. Recent developments in the field of radiotherapy for the management of lung cancer. Jpn J Radiol 2024:10.1007/s11604-024-01663-8. [PMID: 39316285 DOI: 10.1007/s11604-024-01663-8] [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: 08/05/2024] [Accepted: 09/10/2024] [Indexed: 09/25/2024]
Abstract
Lung cancer has a poor prognosis, and further improvements in outcomes are needed. Radiotherapy plays an important role in the treatment of unresectable lung cancer, and there have been recent developments in the field of radiotherapy for the management of lung cancer. However, to date, there have been few reviews on the improvement in treatment outcomes associated with high precision radiotherapy for lung cancer. Thus, this review aimed to summarize the recent developments in radiotherapy techniques and indicate the future directions in the use of radiotherapy for lung cancer. Stereotactic body radiotherapy (SBRT) for unresectable stage I lung cancer has been reported to improve local control rates without severe adverse events, such as radiation pneumonitis. For locally advanced lung cancer, a combination of chemoradiotherapy and adjuvant immune checkpoint inhibitors dramatically improves treatment outcomes, and intensity-modulated radiotherapy (IMRT) enables safer radiation therapy with less frequent pneumonitis. Particle beam therapy, such as carbon-ion radiotherapy and proton beam therapy, has been administered as advanced medical care for patients with lung cancer. Since 2024, it has been covered under insurance for early stage lung cancer with tumors ≤ 5 cm in size in Japan. In addition to chemotherapy, local ablative radiotherapy improves treatment outcomes in patients with oligometastatic stage IV lung cancer. A particular problem with radiotherapy for lung cancer is that the target location changes with respiratory motion, and various physical methods have been used to control respiratory motion. Recently, coronavirus disease has had a major impact on lung cancer treatment, and cancer treatment during situations, such as the coronavirus pandemic, must be performed carefully. To improve treatment outcomes for lung cancer, it is necessary to fully utilize evolving radiotherapy modalities, and the role of radiotherapy in lung cancer treatment is expected to increase.
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Affiliation(s)
- Katsuyuki Shirai
- Department of Radiology, Jichi Medical University Hospital, 3311-1, Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan.
- Department of Radiology, Jichi Medical University Saitama Medical Center, Saitama, Saitama, Japan.
| | - Shuri Aoki
- QST Hospital, National Institutes for Quantum Science and Technology, Anagawa, Chiba, Japan
| | - Masashi Endo
- Department of Radiology, Jichi Medical University Hospital, 3311-1, Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan
| | - Yuta Takahashi
- Department of Radiology, Jichi Medical University Saitama Medical Center, Saitama, Saitama, Japan
| | - Yukiko Fukuda
- Department of Radiology, Jichi Medical University Hospital, 3311-1, Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan
- Department of Radiology, Jichi Medical University Saitama Medical Center, Saitama, Saitama, Japan
| | - Keiko Akahane
- Department of Radiology, Jichi Medical University Saitama Medical Center, Saitama, Saitama, Japan
| | - Atsushi Musha
- Gunma University Heavy Ion Medical Center, Maebashi, Gunma, Japan
| | - Harutoshi Sato
- Department of Radiology, Jichi Medical University Hospital, 3311-1, Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan
| | - Masaru Wakatsuki
- QST Hospital, National Institutes for Quantum Science and Technology, Anagawa, Chiba, Japan
| | - Hitoshi Ishikawa
- QST Hospital, National Institutes for Quantum Science and Technology, Anagawa, Chiba, Japan
| | - Ryohei Sasaki
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
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Wimmert L, Schwarz A, Gauer T, Hofmann C, Dickmann J, Sentker T, Werner R. Impact of breathing signal-guided dose modulation on step-and-shoot 4D CT image reconstruction. Med Phys 2024. [PMID: 39172134 DOI: 10.1002/mp.17360] [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: 04/26/2024] [Revised: 07/27/2024] [Accepted: 07/31/2024] [Indexed: 08/23/2024] Open
Abstract
BACKGROUND Breathing signal-guided 4D CT sequence scanning such as the intelligent 4D CT (i4DCT) approach reduces imaging artifacts compared to conventional 4D CT. By design, i4DCT captures entire breathing cycles during beam-on periods, leading to redundant projection data and increased radiation exposure to patients exhibiting prolonged exhalation phases. A recently proposed breathing-guided dose modulation (DM) algorithm promises to lower the imaging dose by temporarily reducing the CT tube current, but the impact on image reconstruction and the resulting images have not been investigated. PURPOSE We evaluate the impact of breathing signal-guided DM on 4D CT image reconstruction and corresponding images. METHODS This study is designed as a comparative and retrospective analysis based on 104 4D CT datasets. Each dataset underwent retrospective reconstruction twice: (a) utilizing the acquired clinical projection data for reconstruction, which yields reference image data, and (b) excluding projections acquired during potential DM phases from image reconstruction, resulting in DM-affected image data. Resulting images underwent automatic organ segmentation (lung/liver). (Dis)Similarity of reference and DM-affected images were quantified by the Dice coefficient of the entire organ masks and the organ overlaps within the DM-affected slices. Further, for lung cases, (a) and (b) were deformably registered and median magnitudes of the obtained displacement field were computed. Eventually, for 17 lung cases, gross tumor volumes (GTV) were recontoured on both (a) and (b). Target volume similarity was quantified by the Hausdorff distance. RESULTS DM resulted in a median imaging dose reduction of 15.4% (interquartile range [IQR]: 11.3%-19.9%) for the present patient cohort. Dice coefficients for lung (n = 73 $n=73$ ) and liver (n = 31 $n=31$ ) patients were consistently high for both the entire organs and the DM-affected slices (IQR lung:0.985 / 0.982 $0.985/0.982$ [entire lung/DM-affected slices only] to0.992 / 0.989 $0.992/0.989$ ; IQR liver:0.977 / 0.972 $0.977/0.972$ to0.986 / 0.986 $0.986/0.986$ ), demonstrating that DM did not cause organ distortions or alterations. Median displacements for DM-affected to reference image registration varied; however, only two out of 73 cases exhibited a median displacement larger than one isotropic 1mm 3 ${\rm mm}^3$ voxel size. The impact on GTV definition for the end-exhalation phase was also minor (median Hausdorff distance: 0.38 mm, IQR: 0.15-0.46 mm). CONCLUSION This study demonstrates that breathing signal-guided DM has a minimal impact on image reconstruction and image appearance while improving patient safety by reducing dose exposure.
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Affiliation(s)
- Lukas Wimmert
- Institute for Applied Medical Informatics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Center for Biomedical Artificial Intelligence, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Annette Schwarz
- Siemens Healthineers AG, Forchheim, Germany
- Pattern Recognition Lab, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Tobias Gauer
- Department of Radiotherapy and Radiation Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - Thilo Sentker
- Institute for Applied Medical Informatics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Center for Biomedical Artificial Intelligence, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Rene Werner
- Institute for Applied Medical Informatics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Center for Biomedical Artificial Intelligence, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Szkitsak J, Karius A, Fernolendt S, Schubert P, Speer S, Fietkau R, Bert C, Hofmann C. Optimized raw data selection for artifact reduction of breathing controlled four-dimensional sequence scanning. Phys Imaging Radiat Oncol 2024; 30:100584. [PMID: 38803466 PMCID: PMC11128500 DOI: 10.1016/j.phro.2024.100584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 04/10/2024] [Accepted: 05/02/2024] [Indexed: 05/29/2024] Open
Abstract
Background and purpose Even with most breathing-controlled four-dimensional computed tomography (4DCT) algorithms image artifacts caused by single significant longer breathing still occur, resulting in negative consequences for radiotherapy. Our study presents first phantom examinations of a new optimized raw data selection and binning algorithm, aiming to improve image quality and geometric accuracy without additional dose exposure. Materials and methods To validate the new approach, phantom measurements were performed to assess geometric accuracy (volume fidelity, root mean square error, Dice coefficient of volume overlap) for one- and three-dimensional tumor motion trajectories with and without considering motion hysteresis effects. Scans without significantly longer breathing cycles served as references. Results Median volume deviations between optimized approach and reference of at maximum 1% were obtained considering all movements. In comparison, standard reconstruction yielded median deviations of 9%, 21% and 12% for one-dimensional, three-dimensional, and hysteresis motion, respectively. Measurements in one- and three-dimensional directions reached a median Dice coefficient of 0.970 ± 0.013 and 0.975 ± 0.012, respectively, but only 0.918 ± 0.075 for hysteresis motions averaged over all measurements for the optimized selection. However, for the standard reconstruction median Dice coefficients were 0.845 ± 0.200, 0.868 ± 0.205 and 0.915 ± 0.075 for one- and three-dimensional as well as hysteresis motions, respectively. Median root mean square errors for the optimized algorithm were 30 ± 16 HU2 and 120 ± 90 HU2 for three-dimensional and hysteresis motions, compared to 212 ± 145 HU2 and 130 ± 131 HU2 for the standard reconstruction. Conclusions The algorithm was proven to reduce 4DCT-related artifacts due to missing projection data without further dose exposure. An improvement in radiotherapy treatment planning due to better image quality can be expected.
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Affiliation(s)
- Juliane Szkitsak
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Andre Karius
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | | | - Philipp Schubert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Stefan Speer
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Christoph Bert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Comprehensive Cancer Center Erlangen-EMN (CCC ER-EMN), Erlangen, Germany
| | - Christian Hofmann
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Siemens Healthcare GmbH, 91301 Forchheim, Germany
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Keijnemans K, Borman PTS, Raaymakers BW, Fast MF. Effectiveness of visual biofeedback-guided respiratory-correlated 4D-MRI for radiotherapy guidance on the MR-linac. Magn Reson Med 2024; 91:297-311. [PMID: 37799101 DOI: 10.1002/mrm.29857] [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: 01/12/2023] [Revised: 08/18/2023] [Accepted: 08/18/2023] [Indexed: 10/07/2023]
Abstract
PURPOSE Respiratory-correlated 4D-MRI may provide motion characteristics for radiotherapy but is susceptible to irregular breathing. This study investigated the effectiveness of visual biofeedback (VBF) guidance for breathing regularization during 4D-MRI acquisitions on an MR-linac. METHODS A simultaneous multislice-accelerated 4D-MRI sequence was interleaved with a one-dimensional respiratory navigator (1D-RNAV) in 10 healthy volunteers on a 1.5T Unity MR-linac (Elekta AB, Stockholm, Sweden). Volunteer-specific breathing amplitudes and periods were derived from the 1D-RNAV signal obtained during unguided 4D-MRI acquisitions. These were used for the guidance waveform, while the 1D-RNAV positions were overlayed as VBF. VBF effectiveness was quantified by calculating the change in coefficient of variation (CV diff $$ {\mathrm{CV}}^{\mathrm{diff}} $$ ) for the breathing amplitude and period, the position SD of end-exhale, end-inhale and midposition locations, and the agreement between the 1D-RNAV signals and guidance waveforms. The 4D-MRI quality was assessed by quantifying amounts of missing data. RESULTS VBF had an average latency of 520 ± 2 ms. VBF reduced median breathing variations by 18% to 35% (amplitude) and 29% to 57% (period). Median position SD reductions ranged from -3% to 35% (end-exhale), 29% to 38% (end-inhale), and 25% to 37% (midposition). Average differences between guidance waveforms and 1D-RNAV signals were 0.0 s (period) and +1.7 mm (amplitude). VBF also decreased the median amount of missing data by 11% and 29%. CONCLUSION A VBF system was successfully implemented, and all volunteers were able to adapt to the guidance waveform. VBF during 4D-MRI acquisitions drastically reduced breathing variability but had limited effect on missing data in respiratory-correlated 4D-MRI.
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Affiliation(s)
- Katrinus Keijnemans
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Pim T S Borman
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bas W Raaymakers
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Martin F Fast
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
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Sarihan S, Tunc SG, Kahraman A, Irem ZK. Dosimetric comparison of free-breathing versus respiratory motion-managed radiotherapy via four-dimensional computed tomography-based volumetric-modulated arctherapy for lung cancer. Cancer Radiother 2023; 27:698-704. [PMID: 37925346 DOI: 10.1016/j.canrad.2023.05.006] [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: 07/24/2022] [Revised: 10/09/2022] [Accepted: 05/20/2023] [Indexed: 11/06/2023]
Abstract
PURPOSE The aim of this study is to use respiratory motion-managed radiotherapy (RT) to reduce side effects and to compare dosimetric factors with free-breathing planning in patients with lung cancer. MATERIALS AND METHODS Simulation images were obtained in 10 respiratory phases with free breathing using four-dimensional computed tomography (4D-CT) scanner. Planning target volume (PTV) was created with 5mm margins in each direction of the internal target volume delineated using the maximum intensity projection. A volumetric arc treatment (VMAT) plan was created so that the prescribed dose would cover 98% of the PTV. Target volumes for the free-breathing VMAT plan were created according to ICRU Reports 62 and the same prescribed dose was used. RESULTS Patients were evaluated during January 2020. Median 63Gy (59.4-64) RT was administered. Median PTV volumes were 173.53 and 494.50cm3 (P=0.008) and dose covering 95% of PTV volume was 62.97 and 60.51Gy (P=0.13) in 4D-CT based and free-breathing VMAT plans, respectively. The mean and V50 heart dose was 6.03Gy (vs. 10.36Gy, P=0.043) and 8.2% (vs. 33.9%, P=0.007), and significantly lower in 4D-CT based VMAT plans and there was also found a non-significant reduction for other risky organ doses. CONCLUSION Ten patients treated with respiratory motion-managed RT with 4D-CT based VMAT technique. It was observed that PTV did not increase, the target was covered with 95% accuracy, and with statistical significance in heart doses, all risky organ doses were found to be less.
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Affiliation(s)
- S Sarihan
- Department of Radiation Oncology, Faculty of Medicine, Bursa Uludag University, 16059 Bursa, Turkey.
| | - S G Tunc
- Department of Radiation Oncology, Faculty of Medicine, Bursa Uludag University, 16059 Bursa, Turkey.
| | - A Kahraman
- Department of Radiation Oncology, Faculty of Medicine, Bursa Uludag University, 16059 Bursa, Turkey.
| | - Z K Irem
- Department of Radiation Oncology, Faculty of Medicine, Bursa Uludag University, 16059 Bursa, Turkey.
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Schwarz A, Werner R, Wimmert L, Vornehm M, Gauer T, Hofmann C. Dose reduction in sequence scanning 4D CT imaging through respiratory signal-guided tube current modulation: A feasibility study. Med Phys 2023; 50:7539-7547. [PMID: 37831550 DOI: 10.1002/mp.16785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 06/28/2023] [Accepted: 10/01/2023] [Indexed: 10/15/2023] Open
Abstract
BACKGROUND Respiratory signal-guided 4D CT sequence scanning such as the recently introduced Intelligent 4D CT (i4DCT) approach reduces image artifacts compared to conventional 4D CT, especially for irregular breathing. i4DCT selects beam-on periods during scanning such that data sufficiency conditions are fulfilled for each couch position. However, covering entire breathing cycles during beam-on periods leads to redundant projection data and unnecessary dose to the patient during long exhalation phases. PURPOSE We propose and evaluate the feasibility of respiratory signal-guided dose modulation (i.e., temporary reduction of the CT tube current) to reduce the i4DCT imaging dose while maintaining high projection data coverage for image reconstruction. METHODS The study is designed as an in-silico feasibility study. Dose down- and up-regulation criteria were defined based on the patients' breathing signals and their representative breathing cycle learned before and during scanning. The evaluation (including an analysis of the impact of the dose modulation criteria parameters) was based on 510 clinical 4D CT breathing curves. Dose reduction was determined as the fraction of the downregulated dose delivery time to the overall beam-on time. Furthermore, under the assumption of a 10-phase 4D CT and amplitude-based reconstruction, beam-on periods were considered negatively affected by dose modulation if the downregulation period covered an entire phase-specific amplitude range for a specific breathing phase (i.e., no appropriate reconstruction of the phase image possible for this specific beam-on period). Corresponding phase-specific amplitude bins are subsequently denoted as compromised bins. RESULTS Dose modulation resulted in a median dose reduction of 10.4% (lower quartile: 7.4%, upper quartile: 13.8%, maximum: 28.6%; all values corresponding to a default parameterization of the dose modulation criteria). Compromised bins were observed in 1.0% of the beam-on periods (72 / 7370 periods) and affected 10.6% of the curves (54/510 curves). The extent of possible dose modulation depends strongly on the individual breathing patterns and is weakly correlated with the median breathing cycle length (Spearman correlation coefficient 0.22, p < 0.001). Moreover, the fraction of beam-on periods with compromised bins is weakly anti-correlated with the patient's median breathing cycle length (Spearman correlation coefficient -0.24; p < 0.001). Among the curves with the 17% longest average breathing cycles, no negatively affected beam-on periods were observed. CONCLUSION Respiratory signal-guided dose modulation for i4DCT imaging is feasible and promises to significantly reduce the imaging dose with little impact on projection data coverage. However, the impact on image quality remains to be investigated in a follow-up study.
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Affiliation(s)
- Annette Schwarz
- Pattern Recognition Lab, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Siemens Healthcare GmbH, Forchheim, Germany
| | - René Werner
- Institute of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Applied Medical Informatics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Lukas Wimmert
- Institute of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute of Applied Medical Informatics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marc Vornehm
- Siemens Healthcare GmbH, Forchheim, Germany
- Computational Imaging Lab, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Tobias Gauer
- Department of Radiotherapy and Radiation Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Werner R, Szkitsak J, Madesta F, Büttgen L, Wimmert L, Sentker T, Fietkau R, Haderlein M, Bert C, Gauer T, Hofmann C. Clinical application of breathing-adapted 4D CT: image quality comparison to conventional 4D CT. Strahlenther Onkol 2023; 199:686-691. [PMID: 37000223 PMCID: PMC10281893 DOI: 10.1007/s00066-023-02062-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 02/17/2023] [Indexed: 04/01/2023]
Abstract
PURPOSE 4D CT imaging is an integral part of 4D radiotherapy workflows. However, 4D CT data often contain motion artifacts that mitigate treatment planning. Recently, breathing-adapted 4D CT (i4DCT) was introduced into clinical practice, promising artifact reduction in in-silico and phantom studies. Here, we present an image quality comparison study, pooling clinical patient data from two centers: a new i4DCT and a conventional spiral 4D CT patient cohort. METHODS The i4DCT cohort comprises 129 and the conventional spiral 4D CT cohort 417 4D CT data sets of lung and liver tumor patients. All data were acquired for treatment planning. The study consists of three parts: illustration of image quality in selected patients of the two cohorts with similar breathing patterns; an image quality expert rater study; and automated analysis of the artifact frequency. RESULTS Image data of the patients with similar breathing patterns underline artifact reduction by i4DCT compared to conventional spiral 4D CT. Based on a subgroup of 50 patients with irregular breathing patterns, the rater study reveals a fraction of almost artifact-free scans of 89% for i4DCT and only 25% for conventional 4D CT; the quantitative analysis indicated a reduction of artifact frequency by 31% for i4DCT. CONCLUSION The results demonstrate 4D CT image quality improvement for patients with irregular breathing patterns by breathing-adapted 4D CT in this first corresponding clinical data image quality comparison study.
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Affiliation(s)
- René Werner
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Juliane Szkitsak
- Department of Radiation Oncology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
- Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Frederic Madesta
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Laura Büttgen
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Lukas Wimmert
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Thilo Sentker
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
- Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Marlen Haderlein
- Department of Radiation Oncology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
- Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Christoph Bert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, 91054 Erlangen, Germany
- Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Tobias Gauer
- University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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Guberina M, Santiago A, Pöttgen C, Indenkämpen F, Lübcke W, Qamhiyeh S, Gauler T, Hoffmann C, Guberina N, Stuschke M. Respiration-controlled radiotherapy in lung cancer: Systematic evaluation of the optimal application practice. Clin Transl Radiat Oncol 2023; 40:100628. [PMID: 37138702 PMCID: PMC10149340 DOI: 10.1016/j.ctro.2023.100628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 04/05/2023] [Accepted: 04/15/2023] [Indexed: 05/05/2023] Open
Abstract
Background and purpose Definitive radiochemotherapy (RCT) for non-small cell lung cancer (NSCLC) in UICC/TNM I-IVA (singular, oligometastatic) is one of the treatment methods with a potentially curative concept. However, tumour respiratory motion during RT requires exact pre-planning. There are various techniques of motion management like creating internal target volume (ITV), gating, inspiration breath-hold and tracking. The primary goal is to cover the PTV with the prescribed dose while at the same time maximizing dose reduction of surrounding normal tissues (organs at risk, OAR). In this study, two standardized online breath-controlled application techniques used alternately in our department are compared with respect to lung and heart dose. Materials and methods Twenty-four patients who were indicated for thoracic RT received planning CTs in voluntary deep inspiration breath-hold (DIBH) and in free shallow breathing, prospectively gated in expiration (FB-EH). A respiratory gating system by Varian (Real-time Position Management, RPM) was used for monitoring. OAR, GTV, CTV and PTV were contoured on both planning CTs. The PTV margin to the CTV was 5 mm in the axial and 6-8 mm in the cranio-caudal direction. The consistency of the contours was checked by elastic deformation (Varian Eclipse Version 15.5). RT plans were generated and compared in both breathing positions using the same technique, IMRT over fixed irradiation directions or VMAT. The patients were treated in a prospective registry study with the approval of the local ethics committee. Results The PTV in expiration (FB-EH) was on average significantly smaller than the PTV in inspiration (DIBH): for tumours in the lower lobe (LL) 431.5 vs. 477.6 ml (Wilcoxon test for connected samples; p = 0.004), in the upper lobe (UL) 659.5 vs. 686.8 ml (p = 0.005). The intra-patient comparison of plans in DIBH and FB-EH showed superiority of DIBH for UL-tumours and equality of DIBH and FB-EH for LL-tumours. The dose for OAR in UL-tumours was lower in DIBH than in FB-EH (mean lung dose p = 0.011; lungV20, p = 0.002; mean heart dose p = 0.016). The plans for LL-tumours in FB-EH showed no difference in OAR compared to DIBH (mean lung dose p = 0.683; V20Gy p = 0.33; mean heart dose p = 0.929). The RT setting was controlled online for each fraction and was robustly reproducible in FB-EH. Conclusion RT plans for treating lung tumours implemented depend on the reproducibility of the DIBH and advantages of the respiratory situation with respect to OAR. The primary tumour localization in UL correlates with advantages of RT in DIBH, compared to FB-EH. For LL-tumours there is no difference between RT in FB-EH and RT in DIBH with respect to heart or lung exposure and therefore, reproducibility is the dominant criterion. FB-EH is recommended as a very robust and efficient technique for LL-tumours.
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Affiliation(s)
- M. Guberina
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- German Consortium for Translational Cancer Research, Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site University Hospital Essen, Deutsche Krebsforschungszentrum (DKFZ), Essen, Germany
- Corresponding author at: Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Hufealndstr. 55, Essen 45147, Germany.
| | - A. Santiago
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- Medical Physics, Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - C. Pöttgen
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - F. Indenkämpen
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- Medical Physics, Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - W. Lübcke
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- Medical Physics, Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - S. Qamhiyeh
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- Medical Physics, Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - T. Gauler
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - C. Hoffmann
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - N. Guberina
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
| | - M. Stuschke
- Department for Radiotherapy, University Hospital Essen, West German Cancer Center, University Duisburg-Essen, Essen, Germany
- German Consortium for Translational Cancer Research, Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site University Hospital Essen, Deutsche Krebsforschungszentrum (DKFZ), Essen, Germany
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9
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Keijnemans K, Borman PTS, Uijtewaal P, Woodhead PL, Raaymakers BW, Fast MF. A hybrid 2D/4D-MRI methodology using simultaneous multislice imaging for radiotherapy guidance. Med Phys 2022; 49:6068-6081. [PMID: 35694905 PMCID: PMC9545880 DOI: 10.1002/mp.15802] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/18/2022] [Accepted: 05/27/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose Respiratory motion management is important in abdominothoracic radiotherapy. Fast imaging of the tumor can facilitate multileaf collimator (MLC) tracking that allows for smaller treatment margins, while repeatedly imaging the full field‐of‐view is necessary for 4D dose accumulation. This study introduces a hybrid 2D/4D‐MRI methodology that can be used for simultaneous MLC tracking and dose accumulation on a 1.5 T Unity MR‐linac (Elekta AB, Stockholm, Sweden). Methods We developed a hybrid 2D/4D‐MRI methodology that uses a simultaneous multislice (SMS) accelerated MRI sequence, which acquires two coronal slices simultaneously and repeatedly cycles through slice positions over the image volume. As a result, the fast 2D imaging can be used prospectively for MLC tracking and the SMS slices can be sorted retrospectively into respiratory‐correlated 4D‐MRIs for dose accumulation. Data were acquired in five healthy volunteers with an SMS‐bTFE and SMS‐TSE MRI sequence. For each sequence, a prebeam dataset and a beam‐on dataset were acquired simulating the two phases of MR‐linac treatments. Prebeam data were used to generate a 4D‐based motion model and a reference mid‐position volume, while beam‐on data were used for real‐time motion extraction and reconstruction of beam‐on 4D‐MRIs. In addition, an in‐silico computational phantom was used for validation of the hybrid 2D/4D‐MRI methodology. MLC tracking experiments were performed with the developed methodology, for which real‐time SMS data reconstruction was enabled on the scanner. A 15‐beam 8× 7.5 Gy intensity‐modulated radiotherapy plan for lung stereotactic body radiotherapy with isotropic 3 mm GTV‐to‐PTV margins was created. Dosimetry experiments were performed using a 4D motion phantom. The latency between target motion and updating the radiation beam was determined and compensated. Local gamma analyses were performed to quantify dose differences compared to a static reference delivery, and dose area histograms (DAHs) were used to quantify the GTV and PTV coverage. Results In‐vivo data acquisition and MLC tracking experiments were successfully performed with the developed hybrid 2D/4D‐MRI methodology. Real‐time liver–lung interface motion estimation had a Pearson's correlation of 0.996 (in‐vivo) and 0.998 (in‐silico). A median (5th–95th percentile) error of 0.0 (−0.9 to 0.7) mm and 0.0 (−0.2 to 0.2) mm was found for real‐time motion estimation for in‐vivo and in‐silico, respectively. Target motion prediction beyond the liver–lung interface had a median root mean square error of 1.6 mm (in‐vivo) and 0.5 mm (in‐silico). Beam‐on 4D MRI reconstruction required a median amount of data equal to an acquisition time of 2:21–3:17 min, which was 20% less data compared to the prebeam‐derived 4D‐MRI. System latency was reduced from 501 ± 12 ms to −1 ± 3 ms (SMS‐TSE) and from 398 ± 10 ms to −10 ± 4 ms (SMS‐bTFE) by a linear regression prediction filter. The local gamma analysis agreed within −3.8% to 3.3% (SMS‐bTFE) and −5.3% to 10% (SMS‐TSE) with a reference MRI sequence. The DAHs revealed a relative D98% GTV coverage between 97% and 100% (SMS‐bTFE) and 100% and 101% (SMS‐TSE) compared to the static reference. Conclusions The presented 2D/4D‐MRI methodology demonstrated the potential for accurately extracting real‐time motion for MLC tracking in abdominothoracic radiotherapy, while simultaneously reconstructing contiguous respiratory‐correlated 4D‐MRIs for dose accumulation.
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Affiliation(s)
- Katrinus Keijnemans
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Pim T S Borman
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Prescilla Uijtewaal
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Peter L Woodhead
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.,Elekta AB, kungstensgatan 18, 113 57 Stockholm, Sweden
| | - Bas W Raaymakers
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
| | - Martin F Fast
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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10
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Werner R, Szkitsak J, Sentker T, Madesta F, Schwarz A, Fernolendt S, Vornehm M, Gauer T, Bert C, Hofmann C. Comparison of intelligent 4D CT sequence scanning and conventional spiral 4D CT: a first comprehensive phantom study. Phys Med Biol 2021; 66. [PMID: 33171441 DOI: 10.1088/1361-6560/abc93a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/10/2020] [Indexed: 11/11/2022]
Abstract
4D CT imaging is a cornerstone of 4D radiotherapy treatment. Clinical 4D CT data are, however, often affected by severe artifacts. The artifacts are mainly caused by breathing irregularity and retrospective correlation of breathing phase information and acquired projection data, which leads to insufficient projection data coverage to allow for proper reconstruction of 4D CT phase images. The recently introduced 4D CT approach i4DCT (intelligent 4D CT sequence scanning) aims to overcome this problem by breathing signal-driven tube control. The present motion phantom study describes the first in-depth evaluation of i4DCT in a real-world scenario. Twenty-eight 4D CT breathing curves of lung and liver tumor patients with pronounced breathing irregularity were selected to program the motion phantom. For every motion pattern, 4D CT imaging was performed with i4DCT and a conventional spiral 4D CT mode. For qualitative evaluation, the reconstructed 4D CT images were presented to clinical experts, who scored image quality. Further quantitative evaluation was based on established image intensity-based artifact metrics to measure (dis)similarity of neighboring image slices. In addition, beam-on and scan times of the scan modes were analyzed. The expert rating revealed a significantly higher image quality for the i4DCT data. The quantitative evaluation further supported the qualitative: While 20% of the slices of the conventional spiral 4D CT images were found to be artifact-affected, the corresponding fraction was only 4% for i4DCT. The beam-on time (surrogate of imaging dose) did not significantly differ between i4DCT and spiral 4D CT. Overall i4DCT scan times (time between first beam-on and last beam-on event, including scan breaks to compensate for breathing irregularity) were, on average, 53% longer compared to spiral CT. Thus, the results underline that i4DCT significantly improves 4D CT image quality compared to standard spiral CT scanning in the case of breathing irregularity during scanning.
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Affiliation(s)
- René Werner
- University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Juliane Szkitsak
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friederich-Alexander-Universität Erlangen-Nürnberg, 91504 Erlangen, Germany
| | - Thilo Sentker
- University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Frederic Madesta
- University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Annette Schwarz
- Friederich-Alexander-Universität Erlangen-Nürnberg, 91504 Erlangen, Germany.,Siemens Healthcare GmbH, Siemensstr. 3, 91301 Forchheim, Germany
| | - Susanne Fernolendt
- Friederich-Alexander-Universität Erlangen-Nürnberg, 91504 Erlangen, Germany.,Siemens Healthcare GmbH, Siemensstr. 3, 91301 Forchheim, Germany
| | - Marc Vornehm
- Friederich-Alexander-Universität Erlangen-Nürnberg, 91504 Erlangen, Germany.,Siemens Healthcare GmbH, Siemensstr. 3, 91301 Forchheim, Germany
| | - Tobias Gauer
- University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Christoph Bert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friederich-Alexander-Universität Erlangen-Nürnberg, 91504 Erlangen, Germany
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11
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Dumas M, Laugeman E, Sevak P, Snyder KC, Mao W, Chetty IJ, Ajlouni M, Wen N. Technical Note: Comparison of the internal target volume (ITV) contours and dose calculations on 4DCT, average CBCT, and 4DCBCT imaging for lung stereotactic body radiation therapy (SBRT). J Appl Clin Med Phys 2020; 21:288-294. [PMID: 33044040 PMCID: PMC7700943 DOI: 10.1002/acm2.13041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 07/22/2020] [Accepted: 09/15/2020] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To investigate the differences between internal target volumes (ITVs) contoured on the simulation 4DCT and daily 4DCBCT images for lung cancer patients treated with stereotactic body radiotherapy (SBRT) and determine the dose delivered on 4D planning technique. METHODS For nine patients, 4DCBCTs were acquired before each fraction to assess tumor motion. An ITV was contoured on each phase of the 4DCBCT and a union of the 10 ITVs was used to create a composite ITV. Another ITV was drawn on the average 3DCBCT (avgCBCT) to compare with current clinical practice. The Dice coefficient, Hausdorff distance, and center of mass (COM) were averaged over four fractions to compare the ITVs contoured on the 4DCT, avgCBCT, and 4DCBCT for each patient. Planning was done on the average CT, and using the online registration, plans were calculated on each phase of the 4DCBCT and on the avgCBCT. Plan dose calculations were tested by measuring ion chamber dose in the CIRS lung phantom. RESULTS The Dice coefficients were similar for all three comparisons: avgCBCT-to-4DCBCT (0.7 ± 0.1), 4DCT-to-avgCBCT (0.7 ± 0.1), and 4DCT-to-4DCBCT (0.7 ± 0.1); while the mean COM differences were also comparable (2.6 ± 2.2mm, 2.3 ± 1.4mm, and 3.1 ± 1.1mm, respectively). The Hausdorff distances for the comparisons with 4DCBCT (8.2 ± 2.9mm and 8.1 ± 3.2mm) were larger than the comparison without (6.5 ± 2.5mm). The differences in ITV D95% between the treatment plan and avgCBCT calculations were 4.3 ± 3.0% and -0.5 ± 4.6%, between treatment plan and 4DCBCT plans, respectively, while the ITV V100% coverages were 99.0 ± 1.9% and 93.1 ± 8.0% for avgCBCT and 4DCBCT, respectively. CONCLUSION There is great potential for 4DCBCT to evaluate the extent of tumor motion before treatment, but image quality challenges the clinician to consistently delineate lung target volumes.
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Affiliation(s)
- Michael Dumas
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
| | - Eric Laugeman
- Department of Radiation OncologyWashington UniversitySt. LouisMOUSA
| | - Parag Sevak
- Department of Radiation OncologyColumbus Regional HealthColumbusINUSA
| | - Karen C. Snyder
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
| | - Weihua Mao
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
| | - Indrin J. Chetty
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
| | - Munther Ajlouni
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
| | - Ning Wen
- Department of Radiation OncologyHenry Ford Health SystemDetroitMIUSA
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12
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Werner R, Sentker T, Madesta F, Schwarz A, Vornehm M, Gauer T, Hofmann C. Intelligent 4D CT sequence scanning (i4DCT): First scanner prototype implementation and phantom measurements of automated breathing signal-guided 4D CT. Med Phys 2020; 47:2408-2412. [PMID: 32115724 DOI: 10.1002/mp.14106] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/05/2020] [Accepted: 02/20/2020] [Indexed: 11/05/2022] Open
Abstract
PURPOSE Four-dimensional (4D) computed tomography (CT) imaging is an essential part of current 4D radiotherapy treatment planning workflows, but clinical 4D CT images are often affected by artifacts. The artifacts are mainly caused by breathing irregularity during data acquisition, which leads to projection data coverage issues for currently available commercial 4D CT protocols. It was proposed to improve projection data coverage by online respiratory signal analysis and signal-guided CT tube control, but related work was always theoretical and presented as pure in silico studies. The present work demonstrates a first CT prototype implementation along with respective phantom measurements for the recently introduced intelligent 4D CT (i4DCT) sequence scanning concept (https://doi.org/10.1002/mp.13632). METHODS Intelligent 4D CT was implemented on the Siemens SOMATOM go platform. Four-dimensional CT measurements were performed using the CIRS motion phantom. Motion curves were programmed to systematically vary from regular to very irregular, covering typical irregular patterns that are known to result in image artifacts using standard 4D CT imaging protocols. Corresponding measurements were performed using i4DCT and routine spiral 4D CT with similar imaging parameters (e.g., mAs setting and gantry rotation time, retrospective ten-phase reconstruction) to allow for a direct comparison of the image data. RESULTS Following technological implementation of i4DCT on the clinical CT scanner platform, 4D CT motion artifacts were significantly reduced for all investigated levels of breathing irregularity when compared to routine spiral 4D CT scanning. CONCLUSIONS The present study confirms feasibility of fully automated respiratory signal-guided 4D CT scanning by means of a first implementation of i4DCT on a CT scanner. The measurements thereby support the conclusions of respective in silico studies and demonstrate that respiratory signal-guided 4D CT (here: i4DCT) is ready for integration into clinical CT scanners.
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Affiliation(s)
- René Werner
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.,Center for Biomedical Artificial Intelligence (bAIome), University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Thilo Sentker
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.,Department of Radiotherapy and Radio-Oncology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Frederic Madesta
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Annette Schwarz
- Friedrich-Alexander-Universität Erlangen, 91504, Erlangen, Germany.,Siemens Healthcare GmbH, 91301, Forchheim, Germany
| | - Marc Vornehm
- Friedrich-Alexander-Universität Erlangen, 91504, Erlangen, Germany.,Siemens Healthcare GmbH, 91301, Forchheim, Germany
| | - Tobias Gauer
- Department of Radiotherapy and Radio-Oncology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
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13
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Azcona JD, Huesa‐Berral C, Moreno‐Jiménez M, Barbés B, Aristu JJ, Burguete J. A novel concept to include uncertainties in the evaluation of stereotactic body radiation therapy after 4D dose accumulation using deformable image registration. Med Phys 2019; 46:4346-4355. [DOI: 10.1002/mp.13759] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/30/2019] [Accepted: 07/31/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Juan Diego Azcona
- Service of Radiation Physics and Radiation Protection Clínica Universidad de Navarra Avda. Pío XII 31008Pamplona Navarra Spain
| | - Carlos Huesa‐Berral
- Service of Radiation Physics and Radiation Protection Clínica Universidad de Navarra Avda. Pío XII 31008Pamplona Navarra Spain
- Department of Physics and Applied Mathematics, School of Sciences Universidad de Navarra. C/ Irunlarrea 31008Pamplona Navarra Spain
| | - Marta Moreno‐Jiménez
- Service of Radiation Oncology Clínica Universidad de Navarra Avda. Pío XII 31008Pamplona Navarra Spain
| | - Benigno Barbés
- Service of Radiation Physics and Radiation Protection Clínica Universidad de Navarra Avda. Pío XII 31008Pamplona Navarra Spain
| | - José Javier Aristu
- Service of Radiation Oncology Clínica Universidad de Navarra Avda. Pío XII 31008Pamplona Navarra Spain
| | - Javier Burguete
- Department of Physics and Applied Mathematics, School of Sciences Universidad de Navarra. C/ Irunlarrea 31008Pamplona Navarra Spain
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14
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Miyamae Y, Akimoto M, Sasaki M, Fujimoto T, Yano S, Nakamura M. Variation in target volume and centroid position due to breath holding during four-dimensional computed tomography scanning: A phantom study. J Appl Clin Med Phys 2019; 21:11-17. [PMID: 31385421 PMCID: PMC6964747 DOI: 10.1002/acm2.12692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/18/2019] [Accepted: 07/22/2019] [Indexed: 11/08/2022] Open
Abstract
This study investigated the effects of respiratory motion, including unwanted breath holding, on the target volume and centroid position on four‐dimensional computed tomography (4DCT) imaging. Cine 4DCT images were reconstructed based on a time‐based sorting algorithm, and helical 4DCT images were reconstructed based on both the time‐based sorting algorithm and an amplitude‐based sorting algorithm. A spherical object 20 mm in diameter was moved according to several simulated respiratory motions, with a motion period of 4.0 s and maximum amplitude of 5 mm. The object was extracted automatically, and the target volume and centroid position in the craniocaudal direction were measured using a treatment planning system. When the respiratory motion included unwanted breath‐holding times shorter than the breathing cycle, the root mean square errors (RSME) between the reference and imaged target volumes were 18.8%, 14.0%, and 5.5% in time‐based images in cine mode, time‐based images in helical mode, and amplitude‐based images in helical mode, respectively. In helical mode, the RSME between the reference and imaged centroid position was reduced from 1.42 to 0.50 mm by changing the reconstruction method from time‐ to amplitude‐based sorting. When the respiratory motion included unwanted breath‐holding times equal to the breathing cycle, the RSME between the reference and imaged target volumes were 19.1%, 24.3%, and 15.6% in time‐based images in cine mode, time‐based images in helical mode, and amplitude‐based images in helical mode, respectively. In helical mode, the RSME between the reference and imaged centroid position was reduced from 1.61 to 0.83 mm by changing the reconstruction method from time‐ to amplitude‐based sorting. With respiratory motion including breath holding of shorter duration than the breathing cycle, the accuracies of the target volume and centroid position were improved by amplitude‐based sorting, particularly in helical 4DCT.
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Affiliation(s)
- Yuta Miyamae
- Division of Clinical Radiology Service, Kyoto University Hospital, Kyoto, Japan.,Department of Radiological Technology, Radiological Diagnosis, National Cancer Center Hospital, Tokyo, Japan
| | - Mami Akimoto
- Department of Radiation Oncology, Kurashiki Central Hospital, Okayama, Japan
| | - Makoto Sasaki
- Division of Clinical Radiology Service, Kyoto University Hospital, Kyoto, Japan
| | - Takahiro Fujimoto
- Division of Clinical Radiology Service, Kyoto University Hospital, Kyoto, Japan
| | - Shinsuke Yano
- Division of Clinical Radiology Service, Kyoto University Hospital, Kyoto, Japan
| | - Mitsuhiro Nakamura
- Division of Medical Physics, Department of Information Technology and Medical Engineering, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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15
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Werner R, Sentker T, Madesta F, Gauer T, Hofmann C. Intelligent 4D CT sequence scanning (i4DCT): Concept and performance evaluation. Med Phys 2019; 46:3462-3474. [DOI: 10.1002/mp.13632] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/30/2019] [Accepted: 05/22/2019] [Indexed: 12/20/2022] Open
Affiliation(s)
- René Werner
- Department of Computational Neuroscience University Medical Center Hamburg‐Eppendorf 20246Hamburg Germany
| | - Thilo Sentker
- Department of Computational Neuroscience University Medical Center Hamburg‐Eppendorf 20246Hamburg Germany
- Department of Radiotherapy and Radio‐Oncology University Medical Center Hamburg‐Eppendorf 20246Hamburg Germany
| | - Frederic Madesta
- Department of Computational Neuroscience University Medical Center Hamburg‐Eppendorf 20246Hamburg Germany
| | - Tobias Gauer
- Department of Radiotherapy and Radio‐Oncology University Medical Center Hamburg‐Eppendorf 20246Hamburg Germany
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16
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Tian S, Switchenko JM, Cassidy RJ, Escott CE, Castillo R, Patel PR, Curran WJ, Higgins KA. Predictors of pneumonitis-free survival following lung stereotactic body radiation therapy. Transl Lung Cancer Res 2019; 8:15-23. [PMID: 30788231 DOI: 10.21037/tlcr.2018.10.11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background Radiation pneumonitis is a common toxicity following lung stereotactic body radiation therapy (SBRT). We explored whether motion management technique, in conjunction with patient and treatment characteristics, is a predictor of radiation pneumonitis-free survival (PNFS). Methods A single institution multi-center lung SBRT database was retrospectively reviewed. PNFS was defined as time to earliest onset of radiation pneumonitis or last clinical follow-up. Patients were simulated using a 4-dimensional approach, and those with 1 cm or greater tumor motion were selected for respiratory-gated treatment. Real-time Position Management and phase-based gating were employed. Univariate and multivariable Cox proportional hazard models were fit for relevant covariates to determine the impact of free-breathing versus respiratory-gated treatment on PNFS. Results The initial treatment courses of 208 patients were included, with a median follow-up length of 23 months. The median age at treatment was 71 years. About 91.8% of patient had early stage (T1-2) non-small cell lung cancer and were treated with common regimens including 10 Gy ×5, 12 Gy ×4 and 18 Gy ×3; 26.4% underwent respiratory-gated SBRT. The overall rate of grade 3 or higher radiation pneumonitis was 10.1%. PNFS was not significantly different between patients treated with respiratory-gated versus free-breathing SBRT (HR =0.88; P=0.707); tumor location and fractionation were predictors of PNFS in the multivariate setting. Conclusions The method of motion management does not appear to impact PNFS when the tolerance for tumor displacement is 1 cm or less for free-breathing treatment planning and delivery. This approach may be appropriate when selecting patients for respiratory gating.
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Affiliation(s)
- Sibo Tian
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Jeffrey M Switchenko
- Department of Biostatistics and Bioinformatics, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Richard J Cassidy
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Chase E Escott
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Richard Castillo
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Pretesh R Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Walter J Curran
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Kristin A Higgins
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
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17
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Datta A, Aznar MC, Dubec M, Parker GJM, O'Connor JPB. Delivering Functional Imaging on the MRI-Linac: Current Challenges and Potential Solutions. Clin Oncol (R Coll Radiol) 2018; 30:702-710. [PMID: 30224203 DOI: 10.1016/j.clon.2018.08.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/09/2018] [Accepted: 08/20/2018] [Indexed: 12/30/2022]
Abstract
Magnetic resonance imaging (MRI) is a highly versatile imaging modality that can be used to measure features of the tumour microenvironment including cell death, proliferation, metabolism, angiogenesis, and hypoxia. Mapping and quantifying these pathophysiological features has the potential to alter the use of adaptive radiotherapy planning. Although these methods are available for use on diagnostic machines, several challenges exist for implementing these functional MRI methods on the MRI-linear accelerators (linacs). This review considers these challenges and potential solutions.
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Affiliation(s)
- A Datta
- Department of Radiology, The Christie Hospital NHS Trust, Manchester, UK
| | - M C Aznar
- Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - M Dubec
- Division of Cancer Sciences, University of Manchester, Manchester, UK; Christie Medical Physics and Engineering, The Christie Hospital NHS Trust, Manchester, UK
| | - G J M Parker
- Bioxydyn Ltd, Manchester, UK; Centre for Imaging Sciences, University of Manchester, Manchester, UK
| | - J P B O'Connor
- Department of Radiology, The Christie Hospital NHS Trust, Manchester, UK; Division of Cancer Sciences, University of Manchester, Manchester, UK.
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18
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de Blanck SR, Rydhög JS, Larsen KR, Clementsen PF, Josipovic M, Aznar MC, Af Rosenschöld PM, Jølck RI, Specht L, Andresen TL, Persson GF. Long term safety and visibility of a novel liquid fiducial marker for use in image guided radiotherapy of non-small cell lung cancer. Clin Transl Radiat Oncol 2018; 13:24-28. [PMID: 30258990 PMCID: PMC6154396 DOI: 10.1016/j.ctro.2018.07.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/27/2018] [Accepted: 07/31/2018] [Indexed: 11/16/2022] Open
Abstract
Safety and clinical feasibility of injecting a novel liquid fiducial marker for use in image guided radiotherapy in 15 patients with non-small cell lung cancer are reported. No major safety or toxicity issues were encountered. Markers present at start of radiotherapy remained visible in cone beam computed tomography and fluoroscopy images throughout the treatment course and on computed tomography images during follow-up (0-38 months). Marker volume reduction was seen until 9 months after treatment, after which no further marker breakdown was found. No post-treatment migration or marker related complications were found.
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Affiliation(s)
- Steen Riisgaard de Blanck
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Jonas Scherman Rydhög
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark.,Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark
| | - Klaus Richter Larsen
- Department of Respiratory Medicine, Bispebjerg Hospital, Bispebjerg Bakke 23, 2400 København, NV, Denmark
| | - Paul Frost Clementsen
- Department of Respiratory Medicine, Gentofte University Hospital and Copenhagen Academy for Medical Education and Simulation (CAMES), Rigshospitalet, Copenhagen, Denmark
| | - Mirjana Josipovic
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark.,Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark
| | - Marianne Camille Aznar
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark.,Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark
| | - Per Munck Af Rosenschöld
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark.,Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark
| | - Rasmus Irming Jølck
- DTU Nanotech, Department of Micro-and Nanotechnology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Building 345E, Ørsteds Plads, 2800 Kgs. Lyngby, Denmark.,Nanovi Radiotherapy A/S, Diplomvej 373N, 2800 Kgs. Lyngby, Denmark
| | - Lena Specht
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Thomas Lars Andresen
- DTU Nanotech, Department of Micro-and Nanotechnology, Center for Nanomedicine and Theranostics, Technical University of Denmark, Building 345E, Ørsteds Plads, 2800 Kgs. Lyngby, Denmark
| | - Gitte Fredberg Persson
- Department of Oncology, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark
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19
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Molitoris JK, Diwanji T, Snider JW, Mossahebi S, Samanta S, Badiyan SN, Simone CB, Mohindra P. Advances in the use of motion management and image guidance in radiation therapy treatment for lung cancer. J Thorac Dis 2018; 10:S2437-S2450. [PMID: 30206490 PMCID: PMC6123191 DOI: 10.21037/jtd.2018.01.155] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 01/26/2018] [Indexed: 12/22/2022]
Abstract
The development of advanced radiation technologies, including intensity-modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT) and proton therapy, has resulted in increasingly conformal radiation treatments. Recent evidence for the importance of minimizing dose to normal critical structures including the heart and lungs has led to incorporation of these advanced treatment modalities into radiation therapy (RT) for non-small cell lung cancer (NSCLC). While such technologies have allowed for improved dose delivery, implementation requires improved target accuracy with treatments, placing increasing importance on evaluating tumor motion at the time of planning and verifying tumor position at the time of treatment. In this review article, we describe issues and updates related both to motion management and image guidance in the treatment of NSCLC.
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Affiliation(s)
- Jason K. Molitoris
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tejan Diwanji
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - James W. Snider
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
| | - Sina Mossahebi
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
| | - Santanu Samanta
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
| | - Shahed N. Badiyan
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
| | - Charles B. Simone
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
| | - Pranshu Mohindra
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Radiation Oncology, Maryland Proton Treatment Center, University of Maryland, Baltimore, MD, USA
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20
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Aznar MC, Warren S, Hoogeman M, Josipovic M. The impact of technology on the changing practice of lung SBRT. Phys Med 2018; 47:129-138. [PMID: 29331227 PMCID: PMC5883320 DOI: 10.1016/j.ejmp.2017.12.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 11/20/2017] [Accepted: 12/23/2017] [Indexed: 02/09/2023] Open
Abstract
Stereotactic body radiotherapy (SBRT) for lung tumours has been gaining wide acceptance in lung cancer. Here, we review the technological evolution of SBRT delivery in lung cancer, from the first treatments using the stereotactic body frame in the 1990's to modern developments in image guidance and motion management. Finally, we discuss the impact of current technological approaches on the requirements for quality assurance as well as future technological developments.
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Affiliation(s)
- Marianne Camille Aznar
- Clinical Trial Service Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK; Institute for Clinical Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Niels Bohr Institute, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
| | - Samantha Warren
- Hall Edwards Radiotherapy Group, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Mischa Hoogeman
- MC-Daniel den Hoed Cancer Center, Erasmus University, Rotterdam, Netherlands
| | - Mirjana Josipovic
- Niels Bohr Institute, Faculty of Science, University of Copenhagen, Copenhagen, Denmark; Department of Oncology, Section for Radiotherapy, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
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21
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Shiinoki T. [4. Commissioning and Clinical Application of the Respiratory Motion Management in Radiation Therapy]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2018; 74:1352-1359. [PMID: 30464104 DOI: 10.6009/jjrt.2018_jsrt_74.11.1352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Takehiro Shiinoki
- Department of Radiation Oncology, Yamaguchi University Graduate School of Medicine
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22
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Managing an Older Adult with Cancer: Considerations for Radiation Oncologists. BIOMED RESEARCH INTERNATIONAL 2017; 2017:1695101. [PMID: 29387715 PMCID: PMC5745659 DOI: 10.1155/2017/1695101] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/03/2017] [Accepted: 11/16/2017] [Indexed: 02/07/2023]
Abstract
Older adults with cancer present a unique set of management complexities for oncologists and radiation oncologists. Prognosis and resilience to cancer treatments are notably dependent on the presence or risk of "geriatric syndromes," in addition to cancer stage and histology. Recognition, proper evaluation, and management of these conditions in conjunction with management of the cancer itself are critical and can be accomplished by utilization of various geriatric assessment tools. Here we review principles of the geriatric assessment, common geriatric syndromes, and application of these concepts to multidisciplinary oncologic treatment. Older patients may experience toxicities related to treatments that impact treatment effectiveness, quality of life, treatment-related mortality, and treatment compliance. Treatment-related burdens from radiotherapy are increasingly important considerations and include procedural demands, travel, costs, and temporary or permanent loss of functional independence. An overall approach to delivering radiotherapy to an older cancer patient requires a comprehensive assessment of both physical and nonphysical factors that may impact treatment outcome. Patient and family-centered communication is also an important part of developing a shared understanding of illness and reasonable expectations of treatment.
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23
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Tan Z, Liu C, Zhou Y, Shen W. Preliminary comparison of the registration effect of 4D-CBCT and 3D-CBCT in image-guided radiotherapy of Stage IA non-small-cell lung cancer. JOURNAL OF RADIATION RESEARCH 2017; 58:854-861. [PMID: 28992047 PMCID: PMC5710603 DOI: 10.1093/jrr/rrx040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 04/04/2017] [Indexed: 06/07/2023]
Abstract
In this study, we compared the registration effectiveness of 4D cone-beam computed tomography (CBCT) and 3D-CBCT for image-guided radiotherapy in 20 Stage IA non-small-cell lung cancer (NSCLC) patients. Patients underwent 4D-CBCT and 3D-CBCT immediately before radiotherapy, and the X-ray Volume Imaging software system was used for image registration. We performed automatic bone registration and soft tissue registration between 4D-CBCT or 3D-CBCT and 4D-CT images; the regions of interest (ROIs) were the vertebral body on the layer corresponding to the tumor and the internal target volume region. The relative displacement of the gross tumor volume between the 4D-CBCT end-expiratory phase sequence and 4D-CT was used to evaluate the registration error. Among the 20 patients (12 males, 8 females; 35-67 years old; median age, 52 years), 3 had central NSCLC and 17 had peripheral NSCLC, 8 in the upper or middle lobe and 12 in the lower lobe (maximum tumor diameter range, 18-27 mm). The internal motion range in three-dimensional space was 12.52 ± 2.65 mm, accounting for 47.8 ± 15.3% of the maximum diameter of each tumor. The errors of image-guided registration using 4D-CBCT and 3D-CBCT on the x (left-right), y (superior-inferior), z (anterior-posterior) axes, and 3D space were 0.80 ± 0.21 mm and 1.08 ± 0.25 mm, 2.02 ± 0.46 mm and 3.30 ± 0.53 mm, 0.52 ± 0.16 mm and 0.85 ± 0.24 mm, and 2.25 ± 0.44 mm and 3.59 ± 0.48 mm (all P < 0.001), respectively. Thus, 4D-CBCT is preferable to 3D-CBCT for image guidance in small pulmonary tumors because 4D-CBCT can reduce the uncertainty in the tumor location resulting from internal motion caused by respiratory movements, thereby increasing the image-guidance accuracy.
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Affiliation(s)
- Zhibo Tan
- Department of Oncology, Shenzhen Hospital of Southern Medical University, #1333 Xinhu Road, Bao'an District, Shenzhen 518110, Guangdong Province, PR China
- Department of Radiation Oncology, Sichuan Cancer Hospital, #55 Renmin Road South, Wuhou District, Chengdu 610041, Sichuan Province, PR China
| | - Chuanyao Liu
- Department of Rehabilitation, Shenzhen Hospital of Southern Medical University, #1333 Xinhu Road, Bao'an District, Shenzhen 518110, Guangdong Province, PR China
| | - Ying Zhou
- Department of Oncology and Hematology, Shenzhen Hospital of Southern Medical University, #1333 Xinhu Road, Bao'an District, Shenzhen 518110, Guangdong Province, PR China
| | - Weixi Shen
- Department of Oncology, Shenzhen Hospital of Southern Medical University, #1333 Xinhu Road, Bao'an District, Shenzhen 518110, Guangdong Province, PR China
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24
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Abstract
Patient motion can cause misalignment of the tumour and toxicities to the healthy lung tissue during lung stereotactic body radiation therapy (SBRT). Any deviations from the reference setup can miss the target and have acute toxic effects on the patient with consequences onto its quality of life and survival outcomes. Correction for motion, either immediately prior to treatment or intra-treatment, can be realized with image-guided radiation therapy (IGRT) and motion management devices. The use of these techniques has demonstrated the feasibility of integrating complex technology with clinical linear accelerator to provide a higher standard of care for the patients and increase their quality of life.
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Affiliation(s)
- Vincent Caillet
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia; School of Physics, University of Sydney, Sydney, Australia.
| | - Jeremy T Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia; School of Physics, University of Sydney, Sydney, Australia
| | - Paul Keall
- School of Medicine, University of Sydney, Sydney, Australia
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Schwarz M, Cattaneo GM, Marrazzo L. Geometrical and dosimetrical uncertainties in hypofractionated radiotherapy of the lung: A review. Phys Med 2017; 36:126-139. [DOI: 10.1016/j.ejmp.2017.02.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/23/2016] [Accepted: 02/14/2017] [Indexed: 12/25/2022] Open
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Ueda Y, Oohira S, Isono M, Miyazaki M, Teshima T. Asymmetric margin setting at the cranial and caudal sides in respiratory gated and non-gated stereotactic body radiotherapy for lung cancer. Br J Radiol 2015; 89:20150499. [PMID: 26693594 DOI: 10.1259/bjr.20150499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To evaluate total errors, including setup errors, and tumour motion changes with a electronic portal imaging device (EPID) cine at the cranial and caudal sides in respiratory gated and non-gated radiotherapy. METHODS Co-ordinates of the tumour centres (TCs) in the craniocaudal direction were obtained by using four-dimensional CT (4DCT) for each bin and EPID cine frame. During the 100% duty cycle (DC100), 50% duty cycle (DC50) and 30% duty cycle (DC30), both centred on the 50 phase, the co-ordinates of the TCs were compared at the most cranial and caudal positions on both 4DCT and EPID cine. RESULTS During DC100, total errors were -0.2 ± 2.1 and 1.1 ± 2.6 mm at the cranial and caudal sides, respectively. During DC50, the corresponding values were -0.2 ± 2.1 and 1.7 ± 3.2 mm, respectively; during DC30, they were -0.1 ± 2.1 and 1.8 ± 2.9 mm, respectively. The tumour motion changes at the caudal side were strongly correlated with tumour motion observed on 4DCT during DC100 (R(2) = 0.59). CONCLUSION Total errors and tumour motion changes on the caudal side were larger than on the cranial side because of the patients' breathing levels. Owing to variations of the TCs at beam-trigger events, the larger margin was required at the caudal side in gated radiotherapy. ADVANCES IN KNOWLEDGE Variations of the TCs were evaluated at the cranial and caudal sides separately. Providing some margins to compensate for tumour motion changes was a significant requirement at the caudal side in gated and non-gated radiotherapy.
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Affiliation(s)
- Yoshihiro Ueda
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.,2 Department of Radiation Oncology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Shingo Oohira
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.,3 Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Japan
| | - Masaru Isono
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Masayoshi Miyazaki
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Teruki Teshima
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
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27
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Abstract
In this review, image guidance and motion management in radiotherapy for lung cancer is discussed. Motion characteristics of lung tumours and image guidance techniques to obtain motion information are elaborated. Possibilities for management of image guidance and motion in the various steps of the treatment chain are explained, including imaging techniques and beam delivery techniques. Clinical studies using different motion management techniques are reviewed, and finally future directions for image guidance and motion management are outlined.
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Affiliation(s)
- S S Korreman
- Department of Science, Systems and Models, Roskilde University, Roskilde, Denmark
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28
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Yan H, Zhen X, Folkerts M, Li Y, Pan T, Cervino L, Jiang SB, Jia X. A hybrid reconstruction algorithm for fast and accurate 4D cone-beam CT imaging. Med Phys 2015; 41:071903. [PMID: 24989381 DOI: 10.1118/1.4881326] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE 4D cone beam CT (4D-CBCT) has been utilized in radiation therapy to provide 4D image guidance in lung and upper abdomen area. However, clinical application of 4D-CBCT is currently limited due to the long scan time and low image quality. The purpose of this paper is to develop a new 4D-CBCT reconstruction method that restores volumetric images based on the 1-min scan data acquired with a standard 3D-CBCT protocol. METHODS The model optimizes a deformation vector field that deforms a patient-specific planning CT (p-CT), so that the calculated 4D-CBCT projections match measurements. A forward-backward splitting (FBS) method is invented to solve the optimization problem. It splits the original problem into two well-studied subproblems, i.e., image reconstruction and deformable image registration. By iteratively solving the two subproblems, FBS gradually yields correct deformation information, while maintaining high image quality. The whole workflow is implemented on a graphic-processing-unit to improve efficiency. Comprehensive evaluations have been conducted on a moving phantom and three real patient cases regarding the accuracy and quality of the reconstructed images, as well as the algorithm robustness and efficiency. RESULTS The proposed algorithm reconstructs 4D-CBCT images from highly under-sampled projection data acquired with 1-min scans. Regarding the anatomical structure location accuracy, 0.204 mm average differences and 0.484 mm maximum difference are found for the phantom case, and the maximum differences of 0.3-0.5 mm for patients 1-3 are observed. As for the image quality, intensity errors below 5 and 20 HU compared to the planning CT are achieved for the phantom and the patient cases, respectively. Signal-noise-ratio values are improved by 12.74 and 5.12 times compared to results from FDK algorithm using the 1-min data and 4-min data, respectively. The computation time of the algorithm on a NVIDIA GTX590 card is 1-1.5 min per phase. CONCLUSIONS High-quality 4D-CBCT imaging based on the clinically standard 1-min 3D CBCT scanning protocol is feasible via the proposed hybrid reconstruction algorithm.
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Affiliation(s)
- Hao Yan
- Department of Radiation Oncology, The University of Texas, Southwestern Medical Center, Dallas, Texas 75390
| | - Xin Zhen
- Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Michael Folkerts
- Department of Radiation Oncology, The University of Texas, Southwestern Medical Center, Dallas, Texas 75390
| | - Yongbao Li
- Department of Radiation Oncology, The University of Texas, Southwestern Medical Center, Dallas, Texas 75390 and Department of Engineering Physics, Tsinghua University, Beijing 100084, China
| | - Tinsu Pan
- Department of Imaging Physics, The University of Texas, MD Anderson Cancer Center, Houston, Texas 77030
| | - Laura Cervino
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California 92093
| | - Steve B Jiang
- Department of Radiation Oncology, The University of Texas, Southwestern Medical Center, Dallas, Texas 75390
| | - Xun Jia
- Department of Radiation Oncology, The University of Texas, Southwestern Medical Center, Dallas, Texas 75390
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29
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Knopf A, Nill S, Yohannes I, Graeff C, Dowdell S, Kurz C, Sonke JJ, Biegun AK, Lang S, McClelland J, Champion B, Fast M, Wölfelschneider J, Gianoli C, Rucinski A, Baroni G, Richter C, van de Water S, Grassberger C, Weber D, Poulsen P, Shimizu S, Bert C. Challenges of radiotherapy: report on the 4D treatment planning workshop 2013. Phys Med 2014; 30:809-15. [PMID: 25172392 DOI: 10.1016/j.ejmp.2014.07.341] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 07/23/2014] [Accepted: 07/28/2014] [Indexed: 01/27/2023] Open
Abstract
This report, compiled by experts on the treatment of mobile targets with advanced radiotherapy, summarizes the main conclusions and innovations achieved during the 4D treatment planning workshop 2013. This annual workshop focuses on research aiming to advance 4D radiotherapy treatments, including all critical aspects of time resolved delivery, such as in-room imaging, motion detection, motion managing, beam application, and quality assurance techniques. The report aims to revise achievements in the field and to discuss remaining challenges and potential solutions. As main achievements advances in the development of a standardized 4D phantom and in the area of 4D-treatment plan optimization were identified. Furthermore, it was noticed that MR imaging gains importance and high interest for sequential 4DCT/MR data sets was expressed, which represents a general trend of the field towards data covering a longer time period of motion. A new point of attention was work related to dose reconstructions, which may play a major role in verification of 4D treatment deliveries. The experimental validation of results achieved by 4D treatment planning and the systematic evaluation of different deformable image registration methods especially for inter-modality fusions were identified as major remaining challenges. A challenge that was also suggested as focus for future 4D workshops was the adaptation of image guidance approaches from conventional radiotherapy into particle therapy. Besides summarizing the last workshop, the authors also want to point out new evolving demands and give an outlook on the focus of the next workshop.
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Affiliation(s)
| | | | | | | | | | | | | | - Aleksandra K Biegun
- KVI-Center for Advanced Radiation Technology, University of Groningen, Netherlands
| | | | | | | | | | | | - Chiara Gianoli
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Italy; Department of Radiation Oncology, Heidelberg University Hospital, Germany
| | - Antoni Rucinski
- Radiation Oncology Department, SLK-Klinik Heilbronn, Germany
| | - Guido Baroni
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano and Bioengineering Unit, CNAO Foundation, Pavia, Italy
| | - Christian Richter
- Oncoray - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital C.G. Carus, TU Dresden, Helmholtz-Zentrum Dresden-Rossendorf, DKTK, Dresden, Germany
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30
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Cole A, Hanna G, Jain S, O'Sullivan J. Motion Management for Radical Radiotherapy in Non-small Cell Lung Cancer. Clin Oncol (R Coll Radiol) 2014; 26:67-80. [DOI: 10.1016/j.clon.2013.11.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 09/23/2013] [Accepted: 09/24/2013] [Indexed: 11/28/2022]
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31
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Aznar MC, Persson GF, Kofoed IM, Nygaard DE, Korreman SS. Irregular breathing during 4DCT scanning of lung cancer patients: Is the midventilation approach robust? Phys Med 2014; 30:69-75. [DOI: 10.1016/j.ejmp.2013.03.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/11/2013] [Accepted: 03/13/2013] [Indexed: 10/27/2022] Open
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32
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Comparative evaluation of CT-based and respiratory-gated PET/CT-based planning target volume (PTV) in the definition of radiation treatment planning in lung cancer: preliminary results. Eur J Nucl Med Mol Imaging 2013; 41:702-10. [DOI: 10.1007/s00259-013-2594-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 10/01/2013] [Indexed: 12/25/2022]
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33
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Nielsen MS, Nyström MW, Carl J. Potential position errors using fiducial markers for gated image guided radiotherapy. Acta Oncol 2013; 52:1472-6. [PMID: 23984813 DOI: 10.3109/0284186x.2013.814153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Fiducials can be used as surrogate for target position during radiotherapy. However, fiducial motion could lead to potential position errors when using fiducials in four-dimensional computed tomography (4DCT) treatment planning and for gated image guided radiotherapy (IGRT). MATERIAL AND METHODS One gold marker (GM) and 5, 10 and 15 mm nickel-titanium (NiTi) stents were inserted in a moving phantom for the purpose of fiducial detection in 4DCT and gated IGRT. Fiducial position errors in 4DCT and BrainLAB's gated IGRT were defined as residuals between fiducial detection and the actual physical position at the instance of image acquisition. RESULTS Fiducials position errors correlate to speed, fiducial type and orientation during 4DCT acquisition. Lower detection accuracy was measured for the 5 mm NiTi-stent relative to the 10 and 15 mm NiTi stents and GM. Fiducials with orientation 45° relative to the scan direction showed a lower detection accuracy relative to parallel and perpendicular orientations. The standard deviation of position errors in 4DCT were up to 2.2 mm with a maximum deviation of 4.0 mm. Using BrainLAB's gated IGRT the fiducials were detected with a standard deviation of 0.6 mm and a maximum deviation of 1.9 mm. For gated IGRT no correlation to fiducial speed was found. CONCLUSIONS Clinical use of fiducials in combination with treatment planning on mid-ventilation CT phase for moving target should include margins up to 5.5 mm due to potential systematic position errors.
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Affiliation(s)
- Martin S Nielsen
- Department of Medical Physics, Aalborg University Hospital , Denmark
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34
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Chen T, Jabbour SK, Qin S, Haffty BG, Yue N. Objected constrained registration and manifold learning: a new patient setup approach in image guided radiation therapy of thoracic cancer. Med Phys 2013; 40:041710. [PMID: 23556880 PMCID: PMC10745985 DOI: 10.1118/1.4794489] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 02/20/2013] [Accepted: 02/21/2013] [Indexed: 12/16/2022] Open
Abstract
PURPOSE The management of thoracic malignancies with radiation therapy is complicated by continuous target motion. In this study, a real time motion analysis approach is proposed to improve the accuracy of patient setup. METHODS For 11 lung cancer patients a long training fluoroscopy was acquired before the first treatment, and multiple short testing fluoroscopies were acquired weekly at the pretreatment patient setup of image guided radiotherapy (IGRT). The data analysis consisted of three steps: first a 4D target motion model was constructed from 4DCT and projected to the training fluoroscopy through deformable registration. Then the manifold learning method was used to construct a 2D subspace based on the target motion (kinetic) and location (static) information in the training fluoroscopy. Thereafter the respiratory phase in the testing fluoroscopy was determined by finding its location in the subspace. Finally, the phase determined testing fluoroscopy was registered to the corresponding 4DCT to derive the pretreatment patient position adjustment for the IGRT. The method was tested on clinical image sets and numerical phantoms. RESULTS The registration successfully reconstructed the 4D motion model with over 98% volume similarity in 4DCT, and over 95% area similarity in the training fluoroscopy. The machine learning method derived the phase values in over 98% and 93% test images of the phantom and patient images, respectively, with less than 3% phase error. The setup approach achieved an average accumulated setup error less than 1.7 mm in the cranial-caudal direction and less than 1 mm in the transverse plane. All results were validated against the ground truth of manual delineations by an experienced radiation oncologist. The expected total time for the pretreatment setup analysis was less than 10 s. CONCLUSIONS By combining the registration and machine learning, the proposed approach has the potential to improve the accuracy of pretreatment setup for patients with thoracic malignancy.
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Affiliation(s)
- Ting Chen
- Radiation Oncology Department, Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, New Jersey 08901, USA.
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35
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36
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Jaffray DA. Image-guided radiotherapy: from current concept to future perspectives. Nat Rev Clin Oncol 2012; 9:688-99. [DOI: 10.1038/nrclinonc.2012.194] [Citation(s) in RCA: 302] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Cole AJ, McGarry CK, Butterworth KT, Prise KM, O'Sullivan JM, Hounsell AR. Development of a novel experimental model to investigate radiobiological implications of respiratory motion in advanced radiotherapy. Phys Med Biol 2012; 57:N411-20. [DOI: 10.1088/0031-9155/57/22/n411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Abstract
Over the past decade, concomitant chemotherapy and radiotherapy has become the established treatment for patients with stage III non-small-cell lung cancer (NSCLC). Unfortunately, many patients with NSCLC are too old or have multiple comorbidities to withstand such aggressive treatments. Attempts to improve outcomes have included studies of radiotherapy dose escalation and new chemotherapy combinations, as well as adding biological agents and cancer vaccines to existing regimens. Technical radiotherapy modifications, including intensity-modulated radiotherapy and particle beam therapy, have also been investigated. Given the number of potential advances to current models of treatment development, phase III trials of any single new treatment can take years to complete, which is inadequate. To advance research within shorter timescales to improve patient outcomes, we need methods of improving clinical trial accrual, which might require changes in models of research governance, cooperative group activity, trial design and patient consent.
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Mathew L, VanDyk J, Etemad-Rezai R, Rodrigues G, Parraga G. Hyperpolarized 3
He pulmonary functional magnetic resonance imaging prior to radiation therapy. Med Phys 2012; 39:4284-90. [DOI: 10.1118/1.4729713] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Sweeney RA, Seubert B, Stark S, Homann V, Müller G, Flentje M, Guckenberger M. Accuracy and inter-observer variability of 3D versus 4D cone-beam CT based image-guidance in SBRT for lung tumors. Radiat Oncol 2012; 7:81. [PMID: 22682767 PMCID: PMC3484063 DOI: 10.1186/1748-717x-7-81] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 06/08/2012] [Indexed: 12/31/2022] Open
Abstract
Background To analyze the accuracy and inter-observer variability of image-guidance (IG) using 3D or 4D cone-beam CT (CBCT) technology in stereotactic body radiotherapy (SBRT) for lung tumors. Materials and methods Twenty-one consecutive patients treated with image-guided SBRT for primary and secondary lung tumors were basis for this study. A respiration correlated 4D-CT and planning contours served as reference for all IG techniques. Three IG techniques were performed independently by three radiation oncologists (ROs) and three radiotherapy technicians (RTTs). Image-guidance using respiration correlated 4D-CBCT (IG-4D) with automatic registration of the planning 4D-CT and the verification 4D-CBCT was considered gold-standard. Results were compared with two IG techniques using 3D-CBCT: 1) manual registration of the planning internal target volume (ITV) contour and the motion blurred tumor in the 3D-CBCT (IG-ITV); 2) automatic registration of the planning reference CT image and the verification 3D-CBCT (IG-3D). Image quality of 3D-CBCT and 4D-CBCT images was scored on a scale of 1–3, with 1 being best and 3 being worst quality for visual verification of the IGRT results. Results Image quality was scored significantly worse for 3D-CBCT compared to 4D-CBCT: the worst score of 3 was given in 19 % and 7.1 % observations, respectively. Significant differences in target localization were observed between 4D-CBCT and 3D-CBCT based IG: compared to the reference of IG-4D, tumor positions differed by 1.9 mm ± 0.9 mm (3D vector) on average using IG-ITV and by 3.6 mm ± 3.2 mm using IG-3D; results of IG-ITV were significantly closer to the reference IG-4D compared to IG-3D. Differences between the 4D-CBCT and 3D-CBCT techniques increased significantly with larger motion amplitude of the tumor; analogously, differences increased with worse 3D-CBCT image quality scores. Inter-observer variability was largest in SI direction and was significantly larger in IG using 3D-CBCT compared to 4D-CBCT: 0.6 mm versus 1.5 mm (one standard deviation). Inter-observer variability was not different between the three ROs compared to the three RTTs. Conclusions Respiration correlated 4D-CBCT improves the accuracy of image-guidance by more precise target localization in the presence of breathing induced target motion and by reduced inter-observer variability.
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Affiliation(s)
- Reinhart A Sweeney
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str, 11 97080 Wuerzburg, Germany
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