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Li G, Wang G, Wei W, Li Z, Xiao Q, He H, Luo D, Chen L, Li J, Zhang X, Song Y, Bai S. Cardiorespiratory motion characteristics and their dosimetric impact on cardiac stereotactic body radiotherapy. Med Phys 2024. [PMID: 38994881 DOI: 10.1002/mp.17284] [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: 02/05/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/13/2024] Open
Abstract
BACKGROUND Cardiac stereotactic body radiotherapy (CSBRT) is an emerging and promising noninvasive technique for treating refractory arrhythmias utilizing highly precise, single or limited-fraction high-dose irradiations. This method promises to revolutionize the treatment of cardiac conditions by delivering targeted therapy with minimal exposure to surrounding healthy tissues. However, the dynamic nature of cardiorespiratory motion poses significant challenges to the precise delivery of dose in CSBRT, introducing potential variabilities that can impact treatment efficacy. The complexities of the influence of cardiorespiratory motion on dose distribution are compounded by interplay and blurring effects, introducing additional layers of dose uncertainty. These effects, critical to the understanding and improvement of the accuracy of CSBRT, remain unexplored, presenting a gap in current clinical literature. PURPOSE To investigate the cardiorespiratory motion characteristics in arrhythmia patients and the dosimetric impact of interplay and blurring effects induced by cardiorespiratory motion on CSBRT plan quality. METHODS The position and volume variations in the substrate target and cardiac substructures were evaluated in 12 arrhythmia patients using displacement maximum (DMX) and volume metrics. Moreover, a four-dimensional (4D) dose reconstruction approach was employed to examine the dose uncertainty of the cardiorespiratory motion. RESULTS Cardiac pulsation induced lower DMX than respiratory motion but increased the coefficient of variation and relative range in cardiac substructure volumes. The mean DMX of the substrate target was 0.52 cm (range: 0.26-0.80 cm) for cardiac pulsation and 0.82 cm (range: 0.32-2.05 cm) for respiratory motion. The mean DMX of the cardiac structure ranged from 0.15 to 1.56 cm during cardiac pulsation and from 0.35 to 1.89 cm during respiratory motion. Cardiac pulsation resulted in an average deviation of -0.73% (range: -4.01%-4.47%) in V25 between the 3D and 4D doses. The mean deviations in the homogeneity index (HI) and gradient index (GI) were 1.70% (range: -3.10%-4.36%) and 0.03 (range: -0.14-0.11), respectively. For cardiac substructures, the deviations in D50 due to cardiac pulsation ranged from -1.88% to 1.44%, whereas the deviations in Dmax ranged from -2.96% to 0.88% of the prescription dose. By contrast, the respiratory motion led to a mean deviation of -1.50% (range: -10.73%-4.23%) in V25. The mean deviations in HI and GI due to respiratory motion were 4.43% (range: -3.89%-13.98%) and 0.18 (range: -0.01-0.47) (p < 0.05), respectively. Furthermore, the deviations in D50 and Dmax in cardiac substructures for the respiratory motion ranged from -0.28% to 4.24% and -4.12% to 1.16%, respectively. CONCLUSIONS Cardiorespiratory motion characteristics vary among patients, with the respiratory motion being more significant. The intricate cardiorespiratory motion characteristics and CSBRT plan complexity can induce substantial dose uncertainty. Therefore, assessing individual motion characteristics and 4D dose reconstruction techniques is critical for implementing CSBRT without compromising efficacy and safety.
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Affiliation(s)
- Guangjun Li
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Guangyu Wang
- State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Weige Wei
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Zhibin Li
- Department of Radiotherapy & Oncology, The First Affiliated Hospital of Soochow University, Institute of Radiotherapy & Oncology, Soochow University, Suzhou, China
| | - Qing Xiao
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Haiping He
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Dashuang Luo
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Li Chen
- Department of Radiotherapy & Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Jing Li
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xiangyu Zhang
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Ying Song
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Sen Bai
- Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Radiotherapy Physics & Technology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
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Cecchi DD, Ploquin NP, Faruqi S, Morrison H. Impact of abdominal compression on heart and stomach motion for stereotactic arrhythmia radioablation. J Appl Clin Med Phys 2024; 25:e14346. [PMID: 38661250 PMCID: PMC11244678 DOI: 10.1002/acm2.14346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/26/2024] [Accepted: 03/12/2024] [Indexed: 04/26/2024] Open
Abstract
PURPOSE To evaluate the effectiveness of abdominal compression (AC) as a respiratory motion management method for the heart and stomach during stereotactic arrhythmia radioablation (STAR). METHODS 4D computed tomography (4DCT) scans of patients imaged with AC or without AC (free-breathing: FB) were obtained from ventricular-tachycardia (VT) (n = 3), lung cancer (n = 18), and liver cancer (n = 18) patients. Patients treated for VT were imaged both FB and with AC. Lung and liver patients were imaged once with FB or with AC, respectively. The heart, left ventricle (LV), LV components (LVCs), and stomach were contoured on each phase of the 4DCTs. Centre of mass (COM) translations in the left/right (LR), ant/post (AP), and sup/inf (SI) directions were measured for each structure. Minimum distances between LVCs and the stomach over the respiratory cycle were also measured on each 4DCT phase. Mann-Whitney U-tests were performed between AC and FB datasets with a significance of α = 0.05. RESULTS No statistical difference (all p values were >0.05) was found in COM translations between FB and AC patient datasets for all contoured cardiac structures. A reduction in COM translation with AC relative to FB was patient, direction, and structure specific for the three VT patients. A significant decrease in the AP range of motion of the stomach was observed under AC compared to FB. No statistical difference was found between minimum distances to the stomach and LVCs between FB and AC. CONCLUSIONS AC was not a consistent motion management method for STAR, nor does not uniformly affect the separation distance between LVCs and the stomach. If AC is employed in future STAR protocols, the motion of the target volume and its relative distance to the stomach should be compared on two 4DCTs: one while the patient is FB and one under AC.
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Affiliation(s)
- Daniel David Cecchi
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada
- Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta, Canada
| | - Nicolas Paul Ploquin
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada
- Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta, Canada
- Department of Oncology, Division of Medical Physics, University of Calgary, Calgary, Alberta, Canada
| | - Salman Faruqi
- Department of Radiation Oncology, Tom Baker Cancer Centre, Calgary, Alberta, Canada
- Department of Oncology, Division of Radiation Oncology, University of Calgary, Calgary, Alberta, Canada
| | - Hali Morrison
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada
- Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta, Canada
- Department of Oncology, Division of Medical Physics, University of Calgary, Calgary, Alberta, Canada
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Chin V, Finnegan RN, Chlap P, Holloway L, Thwaites DI, Otton J, Delaney GP, Vinod SK. Dosimetric Impact of Delineation and Motion Uncertainties on the Heart and Substructures in Lung Cancer Radiotherapy. Clin Oncol (R Coll Radiol) 2024; 36:420-429. [PMID: 38649309 DOI: 10.1016/j.clon.2024.04.002] [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: 07/17/2023] [Revised: 03/27/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024]
Abstract
AIMS Delineation variations and organ motion produce difficult-to-quantify uncertainties in planned radiation doses to targets and organs at risk. Similar to manual contouring, most automatic segmentation tools generate single delineations per structure; however, this does not indicate the range of clinically acceptable delineations. This study develops a method to generate a range of automatic cardiac structure segmentations, incorporating motion and delineation uncertainty, and evaluates the dosimetric impact in lung cancer. MATERIALS AND METHODS Eighteen cardiac structures were delineated using a locally developed auto-segmentation tool. It was applied to lung cancer planning CTs for 27 curative (planned dose ≥50 Gy) cases, and delineation variations were estimated by using ten mapping-atlases to provide separate substructure segmentations. Motion-related cardiac segmentation variations were estimated by auto-contouring structures on ten respiratory phases for 9/27 cases that had 4D-planning CTs. Dose volume histograms (DVHs) incorporating these variations were generated for comparison. RESULTS Variations in mean doses (Dmean), defined as the range in values across ten feasible auto-segmentations, were calculated for each cardiac substructure. Over the study cohort the median variations for delineation uncertainty and motion were 2.20-11.09 Gy and 0.72-4.06 Gy, respectively. As relative values, variations in Dmean were between 18.7%-65.3% and 7.8%-32.5% for delineation uncertainty and motion, respectively. Doses vary depending on the individual planned dose distribution, not simply on segmentation differences, with larger dose variations to cardiac structures lying within areas of steep dose gradient. CONCLUSION Radiotherapy dose uncertainties from delineation variations and respiratory-related heart motion were quantified using a cardiac substructure automatic segmentation tool. This predicts the 'dose range' where doses to structures are most likely to fall, rather than single DVH curves. This enables consideration of these uncertainties in cardiotoxicity research and for future plan optimisation. The tool was designed for cardiac structures, but similar methods are potentially applicable to other OARs.
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Affiliation(s)
- V Chin
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centres, Department of Radiation Oncology, Sydney, Australia; Ingham Institute for Applied Medical Research, Sydney, Australia; University of Sydney, Image X Institute, Sydney, Australia.
| | - R N Finnegan
- Ingham Institute for Applied Medical Research, Sydney, Australia; University of Sydney, Institute of Medical Physics, Sydney, Australia; Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - P Chlap
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centres, Department of Radiation Oncology, Sydney, Australia; Ingham Institute for Applied Medical Research, Sydney, Australia
| | - L Holloway
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centres, Department of Radiation Oncology, Sydney, Australia; Ingham Institute for Applied Medical Research, Sydney, Australia; University of Sydney, Institute of Medical Physics, Sydney, Australia
| | - D I Thwaites
- University of Sydney, Institute of Medical Physics, Sydney, Australia; St James's Hospital and University of Leeds, Leeds Institute of Medical Research, Radiotherapy Research Group, Leeds, United Kingdom
| | - J Otton
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool Hospital, Department of Cardiology, Sydney, Australia
| | - G P Delaney
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centres, Department of Radiation Oncology, Sydney, Australia; Ingham Institute for Applied Medical Research, Sydney, Australia
| | - S K Vinod
- University of New South Wales, South Western Sydney Clinical School, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centres, Department of Radiation Oncology, Sydney, Australia; Ingham Institute for Applied Medical Research, Sydney, Australia
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Deng Y, Qiu M, Li Y, Wang C, Zhong J, Xiao Z, Wang C, Chen R. A generalized model of cardiac surface motion for evaluating left anterior descending coronary artery dose in left breast cancer radiotherapy. Med Phys 2024. [PMID: 38922708 DOI: 10.1002/mp.17261] [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: 02/09/2024] [Revised: 05/22/2024] [Accepted: 05/22/2024] [Indexed: 06/28/2024] Open
Abstract
BACKGROUND Retrospective studies indicate that radiation damage to left anterior descending coronary artery (LAD) may be critical for late-stage radiation-induced cardiac morbidity. Developing a method that accurately depicts LAD motion and perform dose assessment is crucial. PURPOSE To construct a generalized cardiac surface motion model for LAD dose assessment in left breast cancer radiotherapy. METHODS Cine MRI of 25 cases were divided into training and testing sets for model construction, and five external cases were gathered for generalization validation. Motion prediction from average intensity projection images (AIP) surface point cloud to that of each phase was realized by mapping the relationship between datum points and corresponding points with statistical shape modeling (SSM). Root mean square error (RMSE) for predicted corresponding points and Euclidean distance (ED) for predicted surface point cloud were used to assess model's accuracy. LAD dose assessment for 10 left breast cancer radiotherapy cases was perform by model application. RESULTS The RMSE in testing cases and external cases were 0.209 ± 0.020 mm to 0.841 ± 0.074 mm and 0.895 ± 0.093 mm to 1.912 ± 0.138 mm, respectively; while the ED were 1.399 ± 0.029 mm to 1.658 ± 0.100 mm, 1.571 ± 0.080 mm to 1.779 ± 0.104 mm, respectively, proving the generalized model's high accuracy. The volume of LAD characterizing motion range (WPLAD) (2.392 ± 0.639 cm3) was approximately twice that of LAD from superimposed images (SPLAD) (0.927 ± 0.326 cm3) with p < 0.05, and the former's Dmax (3582.06 ± 575.92 cGy) was significantly larger than latter's (3222.71 ± 665.37 cGy) (p < 0.05). While WPLAD's Dmean (1408.06 ± 413.06 cGy) was slightly smaller than that of SPLAD (1504.15 ± 448.03 cGy), the difference did not reach statistical significance (p > 0.05). WPLAD's V20 (23.42% ± 16.62%) was less than SPLAD's (29.18% ± 21.07%) with p < 0.05, but their comparison in V30 and V40 did not yield statistically significant results. It implies the conventional LAD dose assessment ignores motion impact and may not be justified. CONCLUSIONS The generalized cardiac surface motion model informs LAD dose accurate assessment in left breast cancer radiotherapy.
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Affiliation(s)
- Yongjin Deng
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Minmin Qiu
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Yangchan Li
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Chaoyang Wang
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Jiajian Zhong
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Zhenhua Xiao
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Chengtao Wang
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
| | - Ruiwan Chen
- The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong Province, PR China
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Finnegan RN, Quinn A, Booth J, Belous G, Hardcastle N, Stewart M, Griffiths B, Carroll S, Thwaites DI. Cardiac substructure delineation in radiation therapy - A state-of-the-art review. J Med Imaging Radiat Oncol 2024. [PMID: 38757728 DOI: 10.1111/1754-9485.13668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 04/29/2024] [Indexed: 05/18/2024]
Abstract
Delineation of cardiac substructures is crucial for a better understanding of radiation-related cardiotoxicities and to facilitate accurate and precise cardiac dose calculation for developing and applying risk models. This review examines recent advancements in cardiac substructure delineation in the radiation therapy (RT) context, aiming to provide a comprehensive overview of the current level of knowledge, challenges and future directions in this evolving field. Imaging used for RT planning presents challenges in reliably visualising cardiac anatomy. Although cardiac atlases and contouring guidelines aid in standardisation and reduction of variability, significant uncertainties remain in defining cardiac anatomy. Coupled with the inherent complexity of the heart, this necessitates auto-contouring for consistent large-scale data analysis and improved efficiency in prospective applications. Auto-contouring models, developed primarily for breast and lung cancer RT, have demonstrated performance comparable to manual contouring, marking a significant milestone in the evolution of cardiac delineation practices. Nevertheless, several key concerns require further investigation. There is an unmet need for expanding cardiac auto-contouring models to encompass a broader range of cancer sites. A shift in focus is needed from ensuring accuracy to enhancing the robustness and accessibility of auto-contouring models. Addressing these challenges is paramount for the integration of cardiac substructure delineation and associated risk models into routine clinical practice, thereby improving the safety of RT for future cancer patients.
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Affiliation(s)
- Robert N Finnegan
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
- Institute of Medical Physics, School of Physics, University of Sydney, Sydney, New South Wales, Australia
| | - Alexandra Quinn
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - Jeremy Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
- Institute of Medical Physics, School of Physics, University of Sydney, Sydney, New South Wales, Australia
| | - Gregg Belous
- Australian e-Health Research Centre, Commonwealth Scientific and Industrial Research Organisation, Brisbane, Queensland, Australia
| | - Nicholas Hardcastle
- Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria, Australia
| | - Maegan Stewart
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
- School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Brooke Griffiths
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - Susan Carroll
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
- School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - David I Thwaites
- Institute of Medical Physics, School of Physics, University of Sydney, Sydney, New South Wales, Australia
- Radiotherapy Research Group, Leeds Institute of Medical Research, St James's Hospital and University of Leeds, Leeds, UK
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Liulu X, Balaji P, Barber J, De Silva K, Murray T, Hickey A, Campbell T, Harris J, Gee H, Ahern V, Kumar S, Hau E, Qian PC. Radiation therapy for ventricular arrhythmias. J Med Imaging Radiat Oncol 2024. [PMID: 38698577 DOI: 10.1111/1754-9485.13662] [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: 01/02/2024] [Accepted: 04/15/2024] [Indexed: 05/05/2024]
Abstract
Ventricular arrhythmias (VA) can be life-threatening arrhythmias that result in significant morbidity and mortality. Catheter ablation (CA) is an invasive treatment modality that can be effective in the treatment of VA where medications fail. Recurrence occurs commonly following CA due to an inability to deliver lesions of adequate depth to cauterise the electrical circuits that drive VA or reach areas of scar responsible for VA. Stereotactic body radiotherapy is a non-invasive treatment modality that allows volumetric delivery of energy to treat circuits that cannot be reached by CA. It overcomes the weaknesses of CA and has been successfully utilised in small clinical trials to treat refractory VA. This article summarises the current evidence for this novel treatment modality and the steps that will be required to bring it to the forefront of VA treatment.
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Affiliation(s)
- Xingzhou Liulu
- Cardiology Department, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - Poornima Balaji
- Cardiology Department, Westmead Hospital, University of Sydney, Sydney, New South Wales, Australia
- Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Jeffrey Barber
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Kasun De Silva
- Cardiology Department, Westmead Hospital, University of Sydney, Sydney, New South Wales, Australia
- Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Tiarne Murray
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
| | - Andrew Hickey
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
| | - Timothy Campbell
- Cardiology Department, Westmead Hospital, University of Sydney, Sydney, New South Wales, Australia
- Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Jill Harris
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
| | - Harriet Gee
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Verity Ahern
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Saurabh Kumar
- Cardiology Department, Westmead Hospital, University of Sydney, Sydney, New South Wales, Australia
- Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Eric Hau
- Department of Radiation Oncology, Crown Princess Mary Cancer Centre, Westmead Hospital, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Translational Radiation Biology and Oncology Laboratory, Centre for Cancer Research, The Westmead Institute for Medical Research, Sydney, New South Wales, Australia
- Blacktown Hematology and Cancer Centre, Blacktown Hospital, Blacktown, New South Wales, Australia
| | - Pierre C Qian
- Cardiology Department, Westmead Hospital, University of Sydney, Sydney, New South Wales, Australia
- Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
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Poon J, Thompson RB, Deyell MW, Schellenberg D, Clark H, Reinsberg S, Thomas S. Analysis of left ventricle regional myocardial motion for cardiac radioablation: Left ventricular motion analysis. J Appl Clin Med Phys 2024; 25:e14333. [PMID: 38493500 PMCID: PMC11087184 DOI: 10.1002/acm2.14333] [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: 11/03/2023] [Revised: 02/06/2024] [Accepted: 02/20/2024] [Indexed: 03/19/2024] Open
Abstract
PURPOSE Left ventricle (LV) regional myocardial displacement due to cardiac motion was assessed using cardiovascular magnetic resonance (CMR) cine images to establish region-specific margins for cardiac radioablation treatments. METHODS CMR breath-hold cine images and LV myocardial tissue contour points were analyzed for 200 subjects, including controls (n = 50) and heart failure (HF) patients with preserved ejection fraction (HFpEF, n = 50), mid-range ejection fraction (HFmrEF, n = 50), and reduced ejection fraction (HFrEF, n = 50). Contour points were divided into segments according to the 17-segment model. For each patient, contour point displacements were determined for the long-axis (all 17 segments) and short-axis (segments 1-12) directions. Mean overall, tangential (longitudinal or circumferential), and normal (radial) displacements were calculated for the 17 segments and for each segment level. RESULTS The greatest overall motion was observed in the control group-long axis: 4.5 ± 1.2 mm (segment 13 [apical anterior] epicardium) to 13.8 ± 3.0 mm (segment 6 [basal anterolateral] endocardium), short axis: 4.3 ± 0.8 mm (segment 9 [mid inferoseptal] epicardium) to 11.5 ± 2.3 mm (segment 1 [basal anterior] endocardium). HF patients exhibited lesser motion, with the smallest overall displacements observed in the HFrEF group-long axis: 4.3 ± 1.7 mm (segment 13 [apical anterior] epicardium) to 10.6 ± 3.4 mm (segment 6 [basal anterolateral] endocardium), short axis: 3.9 ± 1.3 mm (segment 8 [mid anteroseptal] epicardium) to 7.4 ± 2.8 mm (segment 1 [basal anterior] endocardium). CONCLUSIONS This analysis provides an estimate of epicardial and endocardial displacement for the 17 segments of the LV for patients with normal and impaired LV function. This reference data can be used to establish treatment planning margin guidelines for cardiac radioablation. Smaller margins may be used for patients with higher degree of impaired heart function, depending on the LV segment.
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Affiliation(s)
- Justin Poon
- Department of Physics and AstronomyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
- Department of Medical PhysicsBC CancerVancouverBritish ColumbiaCanada
| | - Richard B. Thompson
- Department of Biomedical EngineeringUniversity of AlbertaEdmontonAlbertaCanada
| | - Marc W. Deyell
- Heart Rhythm ServicesDivision of CardiologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | | | - Haley Clark
- Department of Physics and AstronomyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
- Department of Medical PhysicsBC CancerSurreyBritish ColumbiaCanada
| | - Stefan Reinsberg
- Department of Physics and AstronomyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Steven Thomas
- Department of Medical PhysicsBC CancerVancouverBritish ColumbiaCanada
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Haberl C, Crean AM, Zelt JGE, Redpath CJ, deKemp RA. Role of Nuclear Imaging in Cardiac Stereotactic Body Radiotherapy for Ablation of Ventricular Tachycardia. Semin Nucl Med 2024; 54:427-437. [PMID: 38658301 DOI: 10.1053/j.semnuclmed.2024.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 04/26/2024]
Abstract
Ventricular tachycardia (VT) is a life-threatening arrhythmia common in patients with structural heart disease or nonischemic cardiomyopathy. Many VTs originate from regions of fibrotic scar tissue, where delayed electrical signals exit scar and re-enter viable myocardium. Cardiac stereotactic body radiotherapy (SBRT) has emerged as a completely noninvasive alternative to catheter ablation for the treatment of recurrent or refractory ventricular tachycardia. While there is no common consensus on the ideal imaging workflow, therapy planning for cardiac SBRT often combines information from a plurality of imaging modalities including MRI, CT, electroanatomic mapping and nuclear imaging. MRI and CT provide detailed anatomic information, and late enhancement contrast imaging can indicate regions of fibrosis. Electroanatomic maps indicate regions of heterogenous conduction voltage or early activation which are indicative of arrhythmogenic tissue. Some early clinical adopters performing cardiac SBRT report the use of myocardial perfusion and viability nuclear imaging to identify regions of scar. Nuclear imaging of hibernating myocardium, inflammation and sympathetic innervation have been studied for ventricular arrhythmia prognosis and in research relating to catheter ablation of VT but have yet to be studied in their potential applications for cardiac SBRT. The integration of information from these many imaging modalities to identify a target for ablation can be challenging. Multimodality image registration and dedicated therapy planning tools may enable higher target accuracy, accelerate therapy planning workflows and improve patient outcomes. Understanding the pathophysiology of ventricular arrhythmias, and localizing the arrhythmogenic tissues, is vital for successful ablation with cardiac SBRT. Nuclear imaging provides an arsenal of imaging strategies to identify regional scar, hibernation, inflammation, and sympathetic denervation with some advantages over alternative imaging strategies.
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Affiliation(s)
- Connor Haberl
- University of Ottawa Heart Institute, Ottawa, ON; Carleton University, Ottawa, ON
| | - Andrew M Crean
- University of Ottawa Heart Institute, Ottawa, ON; North West Heart Center, University of Manchester Foundation NHS Trust, Manchester, UK
| | - Jason G E Zelt
- The Ottawa Hospital, Ottawa, ON; Department of Medicine, University of Ottawa, Ottawa, ON
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Petzl A, Benali K, Mbolamena N, Dyrda K, Rivard L, Seidl S, Martins R, Martinek M, Pürerfellner H, Aguilar M. Patient-specific quantification of cardiorespiratory motion for cardiac stereotactic radioablation treatment planning. Heart Rhythm O2 2024; 5:234-242. [PMID: 38690147 PMCID: PMC11056453 DOI: 10.1016/j.hroo.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024] Open
Abstract
Background Cardiac radioablation is a new treatment for patients with refractory ventricular tachycardia (VT). The target for cardiac radioablation is subject to cardiorespiratory motion (CRM), the heart's movement with breathing and cardiac contraction. Data regarding the magnitude of target CRM are limited but are highly important for treatment planning. Objectives The study sought to assess CRM amplitude by using ablation catheter geometrical data. Methods Electroanatomic mapping data of patients undergoing catheter ablation for VT at 3 academic centers were exported. The spatial position of the ablation catheter as a function of time while in contact with endocardium was analyzed and used to quantify CRM. Results Forty-four patients with ischemic and nonischemic cardiomyopathy and VT contributed 1364 ablation lesions to the analysis. Average cardiac and respiratory excursion were 1.62 ± 1.21 mm and 12.12 ± 4.10 mm, respectively. The average ratio of respiratory to cardiac motion was approximately 11:1. CRM was greatest along the craniocaudal axis (9.66 ± 4.00 mm). Regional variations with respect to respiratory and cardiac motion were observed: basal segments had smaller displacements vs midventricular and apical segments. Patient characteristics (previous cardiac surgery, height, weight, body mass index, and left ventricular ejection fraction) had a statistically significant, albeit clinically moderate, impact on CRM. Conclusion CRM is primarily determined by respiratory displacement and is modulated by the location of the target and the patient's biometric characteristics. The patient-specific quantification of CRM may allow to decrease treatment volume and reduce radiation exposure of surrounding organs at risk while delivering the therapeutic dose to the target.
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Affiliation(s)
- Adrian Petzl
- Electrophysiology Service, Department of Medicine, Montreal Heart Institute and Université de Montréal, Canada
| | - Karim Benali
- Department of Cardiac Electrophysiology, Saint-Etienne University Hospital, France
| | - Nicolas Mbolamena
- Electrophysiology Service, Department of Medicine, Montreal Heart Institute and Université de Montréal, Canada
| | - Katia Dyrda
- Electrophysiology Service, Department of Medicine, Montreal Heart Institute and Université de Montréal, Canada
| | - Léna Rivard
- Electrophysiology Service, Department of Medicine, Montreal Heart Institute and Université de Montréal, Canada
| | - Sebastian Seidl
- Department of Internal Medicine 2/Cardiology, Ordensklinikum Linz Elisabethinen, Linz, Austria
| | - Raphaël Martins
- Department of Cardiac Electrophysiology, Rennes University Hospital, France
| | - Martin Martinek
- Department of Internal Medicine 2/Cardiology, Ordensklinikum Linz Elisabethinen, Linz, Austria
| | - Helmut Pürerfellner
- Department of Internal Medicine 2/Cardiology, Ordensklinikum Linz Elisabethinen, Linz, Austria
| | - Martin Aguilar
- Electrophysiology Service, Department of Medicine, Montreal Heart Institute and Université de Montréal, Canada
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10
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Fast MF, Cao M, Parikh P, Sonke JJ. Intrafraction Motion Management With MR-Guided Radiation Therapy. Semin Radiat Oncol 2024; 34:92-106. [PMID: 38105098 DOI: 10.1016/j.semradonc.2023.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
High quality radiation therapy requires highly accurate and precise dose delivery. MR-guided radiotherapy (MRgRT), integrating an MRI scanner with a linear accelerator, offers excellent quality images in the treatment room without subjecting patient to ionizing radiation. MRgRT therefore provides a powerful tool for intrafraction motion management. This paper summarizes different sources of intrafraction motion for different disease sites and describes the MR imaging techniques available to visualize and quantify intrafraction motion. It provides an overview of MR guided motion management strategies and of the current technical capabilities of the commercially available MRgRT systems. It describes how these motion management capabilities are currently being used in clinical studies, protocols and provides a future outlook.
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Affiliation(s)
- Martin F Fast
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Minsong Cao
- Department of Radiation Oncology, University of California, Los Angeles, CA
| | - Parag Parikh
- Department of Radiation Oncology, Henry Ford Health - Cancer, Detroit, MI
| | - Jan-Jakob Sonke
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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11
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Omidi A, Weiss E, Wilson JS, Rosu-Bubulac M. Effects of respiratory and cardiac motion on estimating radiation dose to the left ventricle during radiotherapy for lung cancer. J Appl Clin Med Phys 2023; 24:e13855. [PMID: 36564951 PMCID: PMC10018663 DOI: 10.1002/acm2.13855] [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: 07/25/2022] [Revised: 10/11/2022] [Accepted: 11/02/2022] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Establish a workflow to evaluate radiotherapy (RT) dose variation induced by respiratory and cardiac motion on the left ventricle (LV) and left ventricular myocardium (LVM). METHODS Eight lung cancer patients underwent 4D-CT, expiratory T1-volumetric-interpolated-breath-hold-examination (VIBE), and cine MRI scans in expiration. Treatment plans were designed on the average intensity projection (AIP) datasets from 4D-CTs. RT dose from AIP was transferred onto 4D-CT respiratory phases. About 50% 4D-CT dose was mapped onto T1-VIBE (following registration) and from there onto average cine MRI datasets. Dose from average cine MRI was transferred onto all cardiac phases. Cumulative cardiac dose was estimated by transferring dose from each cardiac phase onto a reference cine phase following deformable image registration. The LV was contoured on each 4D-CT breathing phase and was called clinical LV (cLV); this structure is blurred by cardiac motion. Additionally, LV, LVM, and an American Heart Association (AHA) model were contoured on all cardiac phases. Relative maximum/mean doses for contoured regions were calculated with respect to each patient's maximum/mean AIP dose. RESULTS During respiration, relative maximum and mean doses on the cLV ranged from -4.5% to 5.6% and -14.2% to 16.5%, respectively, with significant differences in relative mean doses between inspiration and expiration (P < 0.0145). During cardiac motion at expiration, relative maximum and mean doses on the LV ranged from 1.6% to 59.3%, 0.5% to 27.4%, respectively. Relative mean doses were significantly different between diastole and systole (P = 0.0157). No significant differences were noted between systolic, diastolic, or cumulative cardiac doses compared to the expiratory 4D-CT (P > 0.14). Significant differences were observed in AHA segmental doses depending on tumour proximity compared to global LV doses on expiratory 4D-CT (P < 0.0117). CONCLUSION In this study, the LV dose was highest during expiration and diastole. Segmental evaluation suggested that future cardiotoxicity evaluations may benefit from regional assessments of dose that account for cardiopulmonary motion.
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Affiliation(s)
- Alireza Omidi
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Elisabeth Weiss
- Department of Radiation Oncology, Virginia Commonwealth University Health System, Richmond, Virginia, USA
| | - John S Wilson
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, USA.,Pauley Heart Center, Virginia Commonwealth University Health System, Richmond, Virginia, USA
| | - Mihaela Rosu-Bubulac
- Department of Radiation Oncology, Virginia Commonwealth University Health System, Richmond, Virginia, USA
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12
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Harms J, Schreibmann E, Mccall NS, Lloyd MS, Higgins KA, Castillo R. Cardiac motion and its dosimetric impact during radioablation for refractory ventricular tachycardia. J Appl Clin Med Phys 2023:e13925. [PMID: 36747376 DOI: 10.1002/acm2.13925] [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: 09/08/2022] [Revised: 12/09/2022] [Accepted: 01/19/2023] [Indexed: 02/08/2023] Open
Abstract
INTRODUCTION Cardiac radioablation (CR) is a noninvasive treatment option for patients with refractory ventricular tachycardia (VT) during which high doses of radiation, typically 25 Gy, are delivered to myocardial scar. In this study, we investigate motion from cardiac cycle and evaluate the dosimetric impact in a cohort of patients treated with CR. METHODS This retrospective study included eight patients treated at our institution who had respiratory-correlated and ECG-gated 4DCT scans acquired within 2 weeks of CR. Deformable image registration was applied between maximum systole (SYS) and diastole (DIAS) CTs to assess cardiac motion. The average respiratory-correlated CT (AVGresp ) was deformably registered to the average cardiac (AVGcardiac ), SYS, and DIAS CTs, and contours were propagated using the deformation vector fields (DVFs). Finally, the original treatment plan was recalculated on the deformed AVGresp CT for dosimetric assessment. RESULTS Motion magnitudes were measured as the mean (SD) value over the DVFs within each structure. Displacement during the cardiac cycle for all chambers was 1.4 (0.9) mm medially/laterally (ML), 1.6 (1.0) mm anteriorly/posteriorly (AP), and 3.0 (2.8) mm superiorly/inferiorly (SI). Displacement for the 12 distinct clinical target volumes (CTVs) was 1.7 (1.5) mm ML, 2.4 (1.1) mm AP, and 2.1 (1.5) SI. Displacements between the AVGresp and AVGcardiac scans were 4.2 (2.0) mm SI and 5.8 (1.4) mm total. Dose recalculations showed that cardiac motion may impact dosimetry, with dose to 95% of the CTV dropping from 27.0 (1.3) Gy on the AVGresp to 20.5 (7.1) Gy as estimated on the AVGcardiac . CONCLUSIONS Cardiac CTV motion in this patient cohort is on average below 3 mm, location-dependent, and when not accounted for in treatment planning may impact target coverage. Further study is needed to assess the impact of cardiac motion on clinical outcomes.
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Affiliation(s)
- Joseph Harms
- Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Eduard Schreibmann
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia, USA
| | - Neal S Mccall
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia, USA
| | - Michael S Lloyd
- Section of Clinical Cardiac Electrophysiology, Emory University, Atlanta, Georgia, USA
| | - Kristin A Higgins
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia, USA
| | - Richard Castillo
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia, USA
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13
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Aras D, Çetin EHÖ, Ozturk HF, Ozdemir E, Kara M, Ekizler FA, Ozeke O, Ozcan F, Korkmaz A, Kervan U, Turhan N, Coskun N, Tezcan Y, Huang H, Aksu T, Topaloglu S. Stereotactic body radioablation therapy as an immediate and early term antiarrhythmic palliative therapeutic choice in patients with refractory ventricular tachycardia. J Interv Card Electrophysiol 2023; 66:135-143. [PMID: 36040658 PMCID: PMC9424800 DOI: 10.1007/s10840-022-01352-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 08/16/2022] [Indexed: 10/27/2022]
Abstract
BACKGROUND Stereotactic body radioablation therapy (SBRT) has recently been introduced with the ability to provide ablative energy noninvasively to arrhythmogenic substrate while reducing damage to normal cardiac tissue nearby and minimizing patients' procedural risk. There is still debate regarding whether SBRT has a predominant effect in the early or late period after the procedure. We sought to assess the time course of SBRT's efficacy as well as the value of using a blanking period following a SBRT session. METHODS Eight patients (mean age 58 ± 14 years) underwent eight SBRT sessions for refractory ventricular tachycardia (VT). SBRT was given using a linear accelerator device with a total dose of 25 Gy to the targeted area. RESULTS During a median follow-up of 8 months, all patients demonstrated VT recurrences; however, implantable cardioverter-defibrillator (ICD) and anti-tachycardia pacing therapies were significantly reduced with SBRT (8.46 to 0.83/per month, p = 0.047; 18.50 to 3.29/per month, p = 0.036, respectively). While analyzing the temporal SBRT outcomes, the 2 weeks to 3 months period demonstrated the most favorable outcomes. After 6 months, one patient was ICD therapy-free and the remaining patients demonstrated VT episodes. CONCLUSIONS Our findings showed that the SBRT was associated with a marked reduction in the burden of VT and ICD interventions especially during first 3 months. Although SBRT does not seem to succeed complete termination of VT in long-term period, our findings support the strategy that SBRT can be utilized for immediate antiarrhythmic palliation in critically ill patients with otherwise untreatable refractory VT and electrical storm.
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Affiliation(s)
- Dursun Aras
- grid.411781.a0000 0004 0471 9346Department of Cardiology, Istanbul Medipol University, Istanbul, Turkey
| | - Elif Hande Özcan Çetin
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Huseyin Furkan Ozturk
- grid.449874.20000 0004 0454 9762Department of Radiation Oncology, Ankara Yildirim Beyazit University, Ankara City Hospital, Ankara, Turkey
| | - Elif Ozdemir
- grid.449874.20000 0004 0454 9762Department of Nuclear Medicine, Ankara Yildirim Beyazit University, Ankara City Hospital, Ankara, Turkey
| | - Meryem Kara
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Firdevs Aysenur Ekizler
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Ozcan Ozeke
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Firat Ozcan
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Ahmet Korkmaz
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Umit Kervan
- Department of Cardiovascular Surgery, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Nesrin Turhan
- Department of Pathology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Nazim Coskun
- Department of Nuclear Medicine, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
| | - Yilmaz Tezcan
- grid.449874.20000 0004 0454 9762Department of Radiation Oncology, Ankara Yildirim Beyazit University, Ankara City Hospital, Ankara, Turkey
| | - Henry Huang
- grid.262743.60000000107058297Department of Cardiology, Rush Medical College, Chicago, IL USA
| | - Tolga Aksu
- Department of Cardiology, Yeditepe University Istanbul, Istanbul, Turkey, 34100.
| | - Serkan Topaloglu
- Department of Cardiology, University of Health Sciences, Ankara City Hospital, Ankara, Turkey
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14
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Huang SH, Wu YW, Shueng PW, Wang SY, Tsai MC, Liu YH, Chuang WP, Lin HH, Tien HJ, Yeh HP, Hsieh CH. Case report: Stereotactic body radiation therapy with 12 Gy for silencing refractory ventricular tachycardia. Front Cardiovasc Med 2022; 9:973105. [PMID: 36407435 PMCID: PMC9669661 DOI: 10.3389/fcvm.2022.973105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 10/17/2022] [Indexed: 10/25/2023] Open
Abstract
BACKGROUND Encouraging results have been reported for the treatment of ventricular tachycardia (VT) with stereotactic body radiation therapy (SBRT) with 25 Gy. SBRT with 12 Gy for refractory VT was designed to reduce long-term cardiac toxicity. METHODS Stereotactic body radiation therapy-VT simulation, planning, and treatment were performed using standard techniques. A patient was treated with a marginal dose of 12 Gy in a single fraction to the planning target volume (PTV). The goal was for at least ≥ 95% of the PTV to be covered by at least 95% of 12 Gy radiation. RESULTS From April 2021 through June 2022, a patient with refractory VT underwent treatment. The volume for PTV was 65.8 cm3. The mean radiation dose administered to the heart (the heart volume excluding the PTV) was 2.2 Gy. No acute or late toxicity was observed after SBRT. Six months after SBRT, the patient experienced new monomorphic right ventricular outflow tract (RVOT) VT. Interestingly, the substrate of the left ventricular basal to middle posteroseptal wall before SBRT was turned into scar zones with a local voltage < 0.5 mV. Catheter ablation to treat RVOT VT was performed, and the situation remains stable to date. CONCLUSION This study reports the first patient with refractory VT successfully treated with 12.0 Gy SBRT, suggesting that 12 Gy is a potential dose to treat refractory VT. Further investigations and enrollment of more patients are warranted to assess the long-term efficacy and side effects of this treatment.
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Affiliation(s)
- Shan-Hui Huang
- Division of Cardiology, Cardiovascular Medical Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Yen-Wen Wu
- Division of Cardiology, Cardiovascular Medical Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei City, Taiwan
- Department of Nuclear Medicine Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Pei-Wei Shueng
- School of Medicine, National Yang Ming Chiao Tung University, Taipei City, Taiwan
- Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Shan-Ying Wang
- Department of Nuclear Medicine Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei City, Taiwan
| | - Meng-Chieh Tsai
- Division of Radiology, Department of Radiology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Yuan-Hung Liu
- Division of Cardiology, Cardiovascular Medical Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
- Department of Electronic Engineering, Asia Eastern University of Science and Technology, New Taipei City, Taiwan
| | - Wen-Po Chuang
- Division of Cardiology, Cardiovascular Medical Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Heng-Hsu Lin
- Division of Cardiology, Cardiovascular Medical Center, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Hui-Ju Tien
- Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Hsin-Pei Yeh
- Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Chen-Hsi Hsieh
- School of Medicine, National Yang Ming Chiao Tung University, Taipei City, Taiwan
- Division of Radiation Oncology, Department of Radiology, Far Eastern Memorial Hospital, New Taipei City, Taiwan
- School of Medicine, Institute of Traditional Medicine, National Yang Ming Chiao Tung University, Taipei City, Taiwan
- Head and Neck Cancer Surveillance and Research Group, Far Eastern Memorial Hospital, New Taipei City, Taiwan
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15
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Abravan A, Price G, Banfill K, Marchant T, Craddock M, Wood J, Aznar MC, McWilliam A, van Herk M, Faivre-Finn C. Role of Real-World Data in Assessing Cardiac Toxicity After Lung Cancer Radiotherapy. Front Oncol 2022; 12:934369. [PMID: 35928875 PMCID: PMC9344971 DOI: 10.3389/fonc.2022.934369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
Radiation-induced heart disease (RIHD) is a recent concern in patients with lung cancer after being treated with radiotherapy. Most of information we have in the field of cardiac toxicity comes from studies utilizing real-world data (RWD) as randomized controlled trials (RCTs) are generally not practical in this field. This article is a narrative review of the literature using RWD to study RIHD in patients with lung cancer following radiotherapy, summarizing heart dosimetric factors associated with outcome, strength, and limitations of the RWD studies, and how RWD can be used to assess a change to cardiac dose constraints.
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Affiliation(s)
- Azadeh Abravan
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Gareth Price
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Kathryn Banfill
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
| | - Tom Marchant
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Matthew Craddock
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Joe Wood
- Christie Medical Physics and Engineering, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Marianne C. Aznar
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Alan McWilliam
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Marcel van Herk
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
| | - Corinne Faivre-Finn
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom
- Department of Radiotherapy Related Research, The Christie National Health Service (NHS) Foundation Trust, Manchester, United Kingdom
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16
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Piccolo C, Vigorito S, Rondi E, Piperno G, Ferrari A, Pepa M, Riva G, Durante S, Conte E, Catto V, Andreini D, Carbucicchio C, Jereczek-Fossa BA, Pompilio G, Orecchia R, Cattani F. Phantom study of stereotactic radioablation for ventricular tachycardia (STRA-MI-VT) using Cyberknife Synchrony Respiratory Tracking System with a single fiducial marker. Phys Med 2022; 100:135-141. [PMID: 35816942 DOI: 10.1016/j.ejmp.2022.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 06/22/2022] [Accepted: 06/29/2022] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Within the STRA-MI-VT phase Ib/II trial (NCT04066517), the aim of this phantom study was to explore the feasibility of Cyberknife treatments on cardiac lesions by tracking as a single marker the lead tip of an implantable cardioverter defibrillator. The residual displacement of the lesion during the tracking was studied, planning margins were found and the dosimetric accuracy of the treatment was checked. MATERIALS AND METHODS A lead was inserted into a phantom (EasyCube phantom, Sun Nuclear Co, USA) and then placed on the translating ExacTrac Gating System (BrainLAB AG, Germany). The phantom was rotated, a virtual lesion was identified and its displacement during the tracking was studied. Two plans were compared, calculated on the unrotated volume and on the envelope of the unrotated and the rotated volumes. The plans were delivered using the Cyberknife System (Accuray Inc, USA) and their dosimetric accuracy verified by gamma analysis with gafchromic films. RESULTS The residual margin increases enhancing the distance between the lead and the lesion. It is 4 mm for distance 0 cm and 5 mm for distance 5 cm. The coverage is reduced by 3.8% (interquartile range 2.5%-4.7%) when the dose is prescribed on the unrotated volume. All treatment plans are accurate and 3% 3 mm gamma analysis results are greater than 94%. CONCLUSIONS Results showed that tracking with a single marker is feasible considering adequate residual planning margins. The volumes could be further reduced by using additional markers, for example by placing them on the patient's skin.
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Affiliation(s)
- C Piccolo
- Unit of Medical Physics, IEO European Institute of Oncology, IRCCS, Milan, Italy.
| | - S Vigorito
- Unit of Medical Physics, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - E Rondi
- Unit of Medical Physics, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - G Piperno
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - A Ferrari
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - M Pepa
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - G Riva
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - S Durante
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy
| | - E Conte
- Cardiovascular Imaging Department, Centro Cardiologico Monzino IRCCS, Milan, Italy; Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - V Catto
- Department of Clinical Electrophysiology and Cardiac Pacing, Centro Cardiologico Monzino IRCCS, Milan, Italy; Department of Electronics, Information and Biomedical Engineering, Politecnico di Milano, Milan, Italy
| | - D Andreini
- Cardiovascular Imaging Department, Centro Cardiologico Monzino IRCCS, Milan, Italy; Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy
| | - C Carbucicchio
- Department of Clinical Electrophysiology and Cardiac Pacing, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - B A Jereczek-Fossa
- Division of Radiation Oncology, IEO European Institute of Oncology, IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - G Pompilio
- Scientific Directorate, Centro Cardiologico Monzino IRCCS, Milan, Italy; Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - R Orecchia
- Scientific Directorate, IEO European Institute of Oncology IRCCS, Milan, Italy
| | - F Cattani
- Unit of Medical Physics, IEO European Institute of Oncology, IRCCS, Milan, Italy
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17
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Walls GM, Giacometti V, Apte A, Thor M, McCann C, Hanna GG, O'Connor J, Deasy JO, Hounsell AR, Butterworth KT, Cole AJ, Jain S, McGarry CK. Validation of an established deep learning auto-segmentation tool for cardiac substructures in 4D radiotherapy planning scans. Phys Imaging Radiat Oncol 2022; 23:118-126. [PMID: 35941861 PMCID: PMC9356270 DOI: 10.1016/j.phro.2022.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 11/10/2022] Open
Abstract
Cardiotoxicity is a common complication of lung cancer radiotherapy. Segmentation of cardiac substructures is time-consuming and challenging. Deep learning segmentation tools can perform this task in 3D and 4D scans. Performance is high when assessed geometrically, dosimetrically and clinically. Auto-segmentation tools may accelerate clinical workflows and enable research.
Background Emerging data suggest that dose-sparing several key cardiac regions is prognostically beneficial in lung cancer radiotherapy. The cardiac substructures are challenging to contour due to their complex geometry, poor soft tissue definition on computed tomography (CT) and cardiorespiratory motion artefact. A neural network was previously trained to generate the cardiac substructures using three-dimensional radiotherapy planning CT scans (3D-CT). In this study, the performance of that tool on the average intensity projection from four-dimensional (4D) CT scans (4D-AVE), now commonly used in lung radiotherapy, was evaluated. Materials and Methods The 4D-AVE of n=20 patients completing radiotherapy for lung cancer 2015–2020 underwent manual and automated cardiac substructure segmentation. Manual and automated substructures were compared geometrically and dosimetrically. Two senior clinicians also qualitatively assessed the auto-segmentation tool’s output. Results Geometric comparison of the automated and manual segmentations exhibited high levels of similarity across parameters, including volume difference (11.8% overall) and Dice similarity coefficient (0.85 overall), and were consistent with 3D-CT performance. Differences in mean (median 0.2 Gy, range −1.6–0.3 Gy) and maximum (median 0.4 Gy, range −2.2–0.9 Gy) doses to substructures were generally small. Nearly all structures (99.5 %) were deemed to be appropriate for clinical use without further editing. Conclusions Cardiac substructure auto-segmentation using a deep learning-based tool trained on a 3D-CT dataset was feasible on the 4D-AVE scan, meaning this tool is suitable for use on 4D-CT radiotherapy planning scans. Application of this tool would increase the practicality of routine clinical cardiac substructure delineation, and enable further cardiac radiation effects research.
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Evaluation of Motion Compensation Methods for Noninvasive Cardiac Radioablation of Ventricular Tachycardia. Int J Radiat Oncol Biol Phys 2021; 111:1023-1032. [PMID: 34217790 DOI: 10.1016/j.ijrobp.2021.06.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 06/14/2021] [Accepted: 06/23/2021] [Indexed: 11/24/2022]
Abstract
PURPOSE Noninvasive cardiac radioablation is increasingly used for treatment of refractory ventricular tachycardia. Attempts to limit normal tissue exposure are important, including managing motion of the target. An interplay between cardiac and respiratory motion exists for cardiac radioablation, which has not been studied in depth. The objectives of this study were to estimate target motion during abdominal compression free breathing (ACFB) and respiratory gated (RG) deliveries and to investigate the quality of either implanted cardioverter defibrillator lead tip or the diaphragm as a gating surrogate. METHODS AND MATERIALS Eleven patients underwent computed tomography (CT) simulation with an ACFB 4-dimensional CT (r4DCT) and an exhale breath-hold cardiac 4D-CT (c4DCT). The target, implanted cardioverter defibrillator lead tip and diaphragm trajectories were measured for each patient on the r4DCT and c4DCT using rigid registration of each 4D phase to the reference (0%) phase. Motion ranges for ACFB and exhale (40%-60%) RG delivery were estimated from the target trajectories. Surrogate quality was estimated as the correlation with the target motion magnitudes. RESULTS Mean (range) target motion across patients from r4DCT was as follows: left/right (LR), 3.9 (1.7-6.9); anteroposterior (AP), 4.1 (2.2-5.4); and superoinferior (SI), 4.7 (2.2-7.9) mm. Mean (range) target motion from c4DCT was as follows: LR, 3.4 (1.0-4.8); AP, 4.3 (2.6-6.5); and SI, 4.1 (1.4-8.0) mm. For an ACFB, treatment required mean (range) margins to be 4.5 (3.1-6.9) LR, 4.8 (3-6.5) AP, and 5.5 (2.3-8.0) mm SI. For RG, mean (range) internal target volume motion would be 3.6 (1.1-4.8) mm LR, 4.3 (2.6-6.5) mm AP, and 4.2 (2.2-8.0) mm SI. The motion correlations between the surrogates and target showed a high level of interpatient variability. CONCLUSIONS In ACFB patients, a simulated exhale-gated approach did not lead to large projected improvements in margin reduction. Furthermore, the variable correlation between readily available gating surrogates could mitigate any potential advantage to gating and should be evaluated on a patient-specific basis.
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Ren XY, He PK, Gao XS, Zhao ZL, Zhao B, Bai Y, Liu SW, Li K, Qin SB, Ma MW, Zhou J, Rong Y. Dosimetric feasibility of stereotactic ablative radiotherapy in pulmonary vein isolation for atrial fibrillation using intensity-modulated proton therapy. J Appl Clin Med Phys 2021; 22:79-88. [PMID: 33817981 PMCID: PMC8130224 DOI: 10.1002/acm2.13239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 03/03/2021] [Accepted: 03/06/2021] [Indexed: 12/25/2022] Open
Abstract
Purpose To evaluate dosimetric properties of intensity‐modulated proton therapy (IMPT) for simulated treatment planning in patients with atrial fibrillation (AF) targeting left atrial‐pulmonary vein junction (LA‐PVJ), in comparison with volumetric‐modulated arc therapy (VMAT) and helical tomotherapy (TOMO). Methods Ten thoracic 4D‐CT scans with respiratory motion and one with cardiac motion were used for the study. Ten respiratory 4D‐CTs were planned with VMAT, TOMO, and IMPT for simulated AF. Targets at the LA‐PVJ were defined as wide‐area circumferential ablation line. A single fraction of 25 Gy was prescribed to all plans. The interplay effects from cardiac motion were evaluated based on the cardiac 4D‐CT scan. Dose‐volume histograms (DVHs) of the ITV and normal tissues were compared. Statistical analysis was evaluated via one‐way Repeated‐Measures ANOVA and Friedman’s test with Bonferroni’s multiple comparisons test. Results The median volume of ITV was 8.72cc. All plans had adequate target coverage (V23.75Gy ≥ 99%). Compared with VMAT and TOMO, IMPT resulted in significantly lower dose of most normal tissues. For VMAT, TOMO, and IMPT plans, Dmean of the whole heart was 5.52 ± 0.90 Gy, 5.89 ± 0.78 Gy, and 3.01 ± 0.57 Gy (P < 0.001), mean dose of pericardium was 4.74 ± 0.76 Gy, 4.98 ± 0.62 Gy, and 2.59 ± 0.44 Gy (P < 0.001), and D0.03cc of left circumflex artery (LCX) was 13.96 ± 5.45 Gy, 14.34 ± 5.91 Gy, and 8.43 ± 7.24 Gy (P < 0.001), respectively. However, no significant advantage for one technique over the others was observed when examining the D0.03cc of esophagus and main bronchi. Conclusions IMPT targeting LA‐PVJ for patients with AF has high potential to reduce dose to surrounding tissues compared to VMAT or TOMO. Motion mitigation techniques are critical for a particle‐therapy approach.
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Affiliation(s)
- Xue-Ying Ren
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Peng-Kang He
- Department of Cardiology, Peking University First Hospital, Beijing, China
| | - Xian-Shu Gao
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Zhi-Lei Zhao
- Department of Radiation Oncology, Yizhou International Proton Therapy Medical Center, Hebei, China
| | - Bo Zhao
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Yun Bai
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Si-Wei Liu
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Kang Li
- Department of Cardiology, Peking University First Hospital, Beijing, China
| | - Shang-Bin Qin
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Ming-Wei Ma
- Department of Radiation Oncology, Peking University First Hospital, Beijing, China
| | - Jing Zhou
- Department of Cardiology, Peking University First Hospital, Beijing, China
| | - Yi Rong
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, AZ, USA
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Bordoni B, Escher AR. Osteopathic Palpation of the Heart. Cureus 2021; 13:e14187. [PMID: 33816036 PMCID: PMC8008978 DOI: 10.7759/cureus.14187] [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] [Accepted: 03/30/2021] [Indexed: 11/17/2022] Open
Abstract
In the panorama of scientific literature, there is a paucity of literature on how to palpate the heart area in the osteopathic setting and relevant indications on which palpatory sensations the clinician should perceive during the evaluation. The article reviews the fascial anatomy of the heart area and the heart movements derived from magnetic resonance imaging (MRI) studies and describes the landmarks used by the cardiac surgeon to visualize the mediastinal area. The text sets out possible suggestions for a more adequate osteopathic palpatory evaluation and describes any tactile sensations arising from the patient's chest. To the knowledge of the authors, this is the first article that seeks to lay solid foundations for the improvement of osteopathic manual medicine in the cardiology field.
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Affiliation(s)
- Bruno Bordoni
- Physical Medicine and Rehabilitation, Foundation Don Carlo Gnocchi, Milan, ITA
| | - Allan R Escher
- Anesthesiology/Pain Medicine, H. Lee Moffitt Cancer Center and Research Institute, Tampa, USA
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