|
1
|
Nohava L, Czerny R, Tik M, Wurzer D, Laistler E, Frass-Kriegl R. Citizen science approach to assessing patient perception of MRI with flexible radiofrequency coils. Sci Rep 2024; 14:2811. [PMID: 38307928 PMCID: PMC10837436 DOI: 10.1038/s41598-024-53364-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 01/30/2024] [Indexed: 02/04/2024] Open
Abstract
Magnetic Resonance Imaging (MRI) is a major medical imaging modality, which is non-invasive and provides unique soft tissue contrast without ionizing radiation. The successful completion of MRI exams critically depends on patient compliance, and, thus patient comfort. The design, appearance and usability of local MRI radiofrequency (RF) coils potentially influences the patients' perception of the exam. However, systematic investigations and empirical evidence for these aspects are missing. A questionnaire specifically evaluating the impact of RF coils on patient comfort in MRI would be a valuable addition to clinical studies comparing the performance of novel flexible RF coils with standard rigid coils. This paper describes the development of such a questionnaire in the scope of a citizen science (CS) initiative conducted with a group of students at the upper secondary school level. In this work, the CS initiative is presented in the format of a case report and its impact on scientific projects and the students' education is outlined. The resulting questionnaire is made available in German and English so as to be directly applicable by researchers working on the clinical evaluation of novel RF coils or the comfort evaluation of specific hardware setups in general.
Collapse
Affiliation(s)
- Lena Nohava
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Raphaela Czerny
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Martin Tik
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Dagmar Wurzer
- Bundes(real)gymnasium BG/BRG Keimgasse, Mödling, Austria
| | - Elmar Laistler
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Roberta Frass-Kriegl
- High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
| |
Collapse
|
|
2
|
Habermann FNOJ, Schmitt D, Failing T, Ziegler DA, Fischer J, Fischer LA, Guhlich M, Bendrich S, Knaus O, Overbeck TR, Treiber H, von Hammerstein-Equord A, Koch R, El Shafie R, Rieken S, Leu M, Dröge LH. And Yet It Moves: Clinical Outcomes and Motion Management in Stereotactic Body Radiation Therapy (SBRT) of Centrally Located Non-Small Cell Lung Cancer (NSCLC): Shedding Light on the Internal Organ at Risk Volume (IRV) Concept. Cancers (Basel) 2024; 16:231. [PMID: 38201658 PMCID: PMC10778176 DOI: 10.3390/cancers16010231] [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: 12/04/2023] [Revised: 12/27/2023] [Accepted: 12/28/2023] [Indexed: 01/12/2024] Open
Abstract
The internal organ at risk volume (IRV) concept might improve toxicity profiles in stereotactic body radiation therapy (SBRT) for non-small cell lung cancer (NSCLC). We studied (1) clinical aspects in central vs. peripheral tumors, (2) the IRV concept in central tumors, (3) organ motion, and (4) associated normal tissue complication probabilities (NTCPs). We analyzed patients who received SBRT for NSCLC (clinical aspects, n = 78; motion management, n = 35). We found lower biologically effective doses, larger planning target volume sizes, higher lung doses, and worse locoregional control for central vs. peripheral tumors. Organ motion was greater in males and tall patients (bronchial tree), whereas volume changes were lower in patients with a high body mass index (BMI) (esophagus). Applying the IRV concept (retrospectively, without new optimization), we found an absolute increase of >10% in NTCPs for the bronchial tree in three patients. This study emphasizes the need to optimize methods to balance dose escalation with toxicities in central tumors. There is evidence that organ motion/volume changes could be more pronounced in males and tall patients, and less pronounced in patients with higher BMI. Since recent studies have made efforts to further subclassify central tumors to refine treatment, the IRV concept should be considered for optimal risk assessment.
Collapse
Affiliation(s)
- Felix-Nikolai Oschinka Jegor Habermann
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Daniela Schmitt
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Thomas Failing
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
- Institute of Medical Physics and Radiation Protection (IMPS), University of Applied Sciences, Wiesenstr. 14, 35390 Gießen, Germany
| | - David Alexander Ziegler
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Jann Fischer
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Laura Anna Fischer
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Manuel Guhlich
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Stephanie Bendrich
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Olga Knaus
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Tobias Raphael Overbeck
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
- Department of Hematology and Medical Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Hannes Treiber
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
- Department of Hematology and Medical Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Alexander von Hammerstein-Equord
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
- Department of Cardio-Thoracic and Vascular Surgery, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Raphael Koch
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
- Department of Hematology and Medical Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Rami El Shafie
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Stefan Rieken
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Martin Leu
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| | - Leif Hendrik Dröge
- Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany; (F.-N.O.J.H.); (D.S.); (D.A.Z.); (J.F.); (L.A.F.); (M.G.); (S.B.); (R.E.S.); (S.R.); (M.L.)
- Göttingen Comprehensive Cancer Center (G-CCC), University Medical Center Göttingen, Von-Bar-Str. 2/4, 37075 Göttingen, Germany; (T.R.O.); (H.T.); (A.v.H.-E.); (R.K.)
| |
Collapse
|
|
3
|
Obermann M, Nohava L, Frass-Kriegl R, Soanca O, Ginefri JC, Felblinger J, Clauser P, Baltzer PA, Laistler E. Panoramic Magnetic Resonance Imaging of the Breast With a Wearable Coil Vest. Invest Radiol 2023; 58:799-810. [PMID: 37227137 PMCID: PMC10581436 DOI: 10.1097/rli.0000000000000991] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/21/2023] [Indexed: 05/26/2023]
Abstract
BACKGROUND Breast cancer, the most common malignant cancer in women worldwide, is typically diagnosed by x-ray mammography, which is an unpleasant procedure, has low sensitivity in women with dense breasts, and involves ionizing radiation. Breast magnetic resonance imaging (MRI) is the most sensitive imaging modality and works without ionizing radiation, but is currently constrained to the prone imaging position due to suboptimal hardware, therefore hampering the clinical workflow. OBJECTIVES The aim of this work is to improve image quality in breast MRI, to simplify the clinical workflow, shorten measurement time, and achieve consistency in breast shape with other procedures such as ultrasound, surgery, and radiation therapy. MATERIALS AND METHODS To this end, we propose "panoramic breast MRI"-an approach combining a wearable radiofrequency coil for 3 T breast MRI (the "BraCoil"), acquisition in the supine position, and a panoramic visualization of the images. We demonstrate the potential of panoramic breast MRI in a pilot study on 12 healthy volunteers and 1 patient, and compare it to the state of the art. RESULTS With the BraCoil, we demonstrate up to 3-fold signal-to-noise ratio compared with clinical standard coils and acceleration factors up to 6 × 4. Panoramic visualization of supine breast images reduces the number of slices to be viewed by a factor of 2-4. CONCLUSIONS Panoramic breast MRI allows for high-quality diagnostic imaging and facilitated correlation to other diagnostic and interventional procedures. The developed wearable radiofrequency coil in combination with dedicated image processing has the potential to improve patient comfort while enabling more time-efficient breast MRI compared with clinical coils.
Collapse
|
|
4
|
Lecoeur B, Barbone M, Gough J, Oelfke U, Luk W, Gaydadjiev G, Wetscherek A. Accelerating 4D image reconstruction for magnetic resonance-guided radiotherapy. Phys Imaging Radiat Oncol 2023; 27:100484. [PMID: 37664799 PMCID: PMC10474606 DOI: 10.1016/j.phro.2023.100484] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 09/05/2023] Open
Abstract
Background and purpose Physiological motion impacts the dose delivered to tumours and vital organs in external beam radiotherapy and particularly in particle therapy. The excellent soft-tissue demarcation of 4D magnetic resonance imaging (4D-MRI) could inform on intra-fractional motion, but long image reconstruction times hinder its use in online treatment adaptation. Here we employ techniques from high-performance computing to reduce 4D-MRI reconstruction times below two minutes to facilitate their use in MR-guided radiotherapy. Material and methods Four patients with pancreatic adenocarcinoma were scanned with a radial stack-of-stars gradient echo sequence on a 1.5T MR-Linac. Fast parallelised open-source implementations of the extra-dimensional golden-angle radial sparse parallel algorithm were developed for central processing unit (CPU) and graphics processing unit (GPU) architectures. We assessed the impact of architecture, oversampling and respiratory binning strategy on 4D-MRI reconstruction time and compared images using the structural similarity (SSIM) index against a MATLAB reference implementation. Scaling and bottlenecks for the different architectures were studied using multi-GPU systems. Results All reconstructed 4D-MRI were identical to the reference implementation (SSIM > 0.99). Images reconstructed with overlapping respiratory bins were sharper at the cost of longer reconstruction times. The CPU + GPU implementation was over 17 times faster than the reference implementation, reconstructing images in 60 ± 1 s and hyper-scaled using multiple GPUs. Conclusion Respiratory-resolved 4D-MRI reconstruction times can be reduced using high-performance computing methods for online workflows in MR-guided radiotherapy with potential applications in particle therapy.
Collapse
Affiliation(s)
- Bastien Lecoeur
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, 15 Cotswold Rd, London SM2 5NG, United Kingdom
- Department of Computing, Imperial College London, Exhibition Rd, South Kensington, London SW7 2BX, United Kingdom
| | - Marco Barbone
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, 15 Cotswold Rd, London SM2 5NG, United Kingdom
- Department of Computing, Imperial College London, Exhibition Rd, South Kensington, London SW7 2BX, United Kingdom
| | - Jessica Gough
- Department of Radiotherapy at the Royal Marsden NHS Foundation Trust, Downs Rd, London SM2 5PT, United Kingdom
| | - Uwe Oelfke
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, 15 Cotswold Rd, London SM2 5NG, United Kingdom
| | - Wayne Luk
- Department of Computing, Imperial College London, Exhibition Rd, South Kensington, London SW7 2BX, United Kingdom
| | - Georgi Gaydadjiev
- Department of Computing, Imperial College London, Exhibition Rd, South Kensington, London SW7 2BX, United Kingdom
- Bernoulli Institute, University of Groningen, Nijenborgh 9, Groningen 9747 AG, The Netherlands
| | - Andreas Wetscherek
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, 15 Cotswold Rd, London SM2 5NG, United Kingdom
| |
Collapse
|
|
5
|
Nielsen AWM, Spejlborg H, Lutz CM, Rugaard Poulsen P, Offersen BV. Difference between planned and delivered radiotherapy dose to the internal mammary nodes in high-risk breast cancer patients. Phys Imaging Radiat Oncol 2023; 27:100470. [PMID: 37533551 PMCID: PMC10393587 DOI: 10.1016/j.phro.2023.100470] [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: 05/02/2023] [Revised: 07/05/2023] [Accepted: 07/06/2023] [Indexed: 08/04/2023] Open
Abstract
Background and purpose Chest wall movement during radiotherapy can impact the delivered dose to the internal mammary nodes (IMN) in high-risk breast cancer patients. Using portal imaging and dose reconstruction we aimed to examine the delivered IMN dose coverage. Material and methods Cine MV images were recorded for 39 breast cancer patients treated with daily image-guided radiotherapy (IGRT) in deep-inspiration breath-hold (DIBH). On the final frame of each cine MV recording the chest wall was matched with the Digitally Reconstructed Radiograph (DRR) from the treatment plan. The geometrical chest wall error was determined in the imager-plane perpendicular to the cranio-caudal direction, rounded to integer millimeters, and binned. For each 1 mm bin, an isocenter-shifted treatment plan was recalculated assuming that the projected error observed in the cine MV image was caused by anterior-posterior chest wall movement in the IMN region. A weighted plan sum yielded the IMN clinical target volume receiving at least 90% dose (V90_CTVn_IMN). Results The mean number of cine MV observations per patient was 36 (range 26-55). Most patients (67%) had on average a posterior chest wall position at treatment compared to planned. This translated into a change in the delivered median V90_CTVn_IMN of -0.7% (range, -11.9-2.9%; p < 0.001). The V90_CTVn_IMN reduction was greater than 9% in three patients. No clinically relevant differences were found for the mean lung dose or mean heart dose. Conclusion Using cine MV images, we found that the delivered V90_CTVn_IMN was significantly lower than planned. In 8% of the patients, the V90_CTVn_IMN reduction exceeded 9%.
Collapse
Affiliation(s)
| | - Harald Spejlborg
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Per Rugaard Poulsen
- Danish Center for Particle Therapy, Aarhus University Hospital, Denmark
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Birgitte Vrou Offersen
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark
- Danish Center for Particle Therapy, Aarhus University Hospital, Denmark
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
|
6
|
Carr MA, Gargett M, Stanton C, Zwan B, Byrne HL, Booth JT. A method for beam's eye view breath-hold monitoring during breast volumetric modulated arc therapy. Phys Imaging Radiat Oncol 2023; 25:100419. [PMID: 36875326 PMCID: PMC9975298 DOI: 10.1016/j.phro.2023.100419] [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: 09/08/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023] Open
Abstract
Background and purpose Deep inspiration breath-hold (DIBH) is a technique that is widely utilised to spare the heart and lungs during breast radiotherapy. In this study, a method was developed to validate directly the intrafraction accuracy of DIBH during breast volumetric modulated arc therapy (VMAT) via internal chest wall (CW) monitoring. Materials and methods In-house software was developed to automatically extract and compare the treatment position of the CW in cine-mode electronic portal image device (EPID) images with the planned CW position in digitally reconstructed radiographs (DRR) for breast VMAT treatments. Feasibility of this method was established by evaluating the percentage of total dose delivered to the target volume when the CW was sufficiently visible for monitoring. Geometric accuracy of the approach was quantified by applying known displacements to an anthropomorphic thorax phantom. The software was used to evaluate (offline) the geometric treatment accuracy for ten patients treated using real-time position management (RPM)-guided DIBH. Results The CW could be monitored within the tangential sub-arcs which delivered a median 89% (range 73% to 97%) of the dose to target volume. The phantom measurements showed a geometric accuracy within 1 mm, with visual inspection showing good agreement between the software-derived and user-determined CW positions. For the RPM-guided DIBH treatments, the CW was found to be within ±5 mm of the planned position in 97% of EPID frames in which the CW was visible. Conclusion An intrafraction monitoring method with sub-millimetre accuracy was successfully developed to validate target positioning during breast VMAT DIBH.
Collapse
Affiliation(s)
- M A Carr
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia.,Institute of Medical Physics, School of Physics, The University of Sydney, Sydney, New South Wales, Australia
| | - M Gargett
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia.,School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - C Stanton
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia
| | - B Zwan
- Central Coast Cancer Centre, Gosford Hospital, Gosford, New South Wales, Australia
| | - H L Byrne
- ACRF Image-X Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - J T Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales, Australia.,Institute of Medical Physics, School of Physics, The University of Sydney, Sydney, New South Wales, Australia
| |
Collapse
|