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Muecke J, Reitz D, Huang L, da Silva Mendes V, Landry G, Reiner M, Belka C, Freislederer P, Corradini S, Niyazi M. Intrafractional motion detection for spine SBRT via X-ray imaging using ExacTrac Dynamic. Clin Transl Radiat Oncol 2024; 46:100765. [PMID: 38560512 PMCID: PMC10979138 DOI: 10.1016/j.ctro.2024.100765] [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: 07/21/2023] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 04/04/2024] Open
Abstract
Purpose Due to its close vicinity to critical structures, especially the spinal cord, standards for safety for spine stereotactic body radiotherapy (SBRT) should be high. This study was conducted, to evaluate intrafractional motion during spine SBRT for patients without individualized immobilization (e.g., vacuum cushions) using high accuracy patient monitoring via orthogonal X-ray imaging. Methods Intrafractional X-ray data were collected from 29 patients receiving 79 fractions of spine SBRT. No individualized immobilization devices were used during the treatment. Intrafractional motion was monitored using the ExacTrac Dynamic (ETD) System (Brainlab AG, Munich, Germany). Deviations were detected in six degrees of freedom (6 DOF). Tolerances for repositioning were 0.7 mm for translational and 0.5° for rotational deviations. Patients were repositioned when the tolerance levels were exceeded. Results Out of the 925 pairs of stereoscopic X-ray images examined, 138 (15 %) showed at least one deviation exceeding the predefined tolerance values. In all 6 DOF together, a total of 191 deviations out of tolerance were recorded. The frequency of deviations exceeding the tolerance levels varied among patients but occurred in all but one patient. Deviations out of tolerance could be seen in all 6 DOF. Maximum translational deviations were 2.6 mm, 2.3 mm and 2.8 mm in the lateral, longitudinal and vertical direction. Maximum rotational deviations were 1.8°, 2.6° and 1.6° for pitch, roll and yaw, respectively. Translational deviations were more frequent than rotational ones, and frequency and magnitude of deviations showed an inverse correlation. Conclusion Intrafractional motion detection and patient repositioning during spine SBRT using X-ray imaging via the ETD System can lead to improved safety during the application of high BED in critical locations. When using intrafractional imaging with low thresholds for re-positioning individualized immobilization devices (e.g. vacuum cushions) may be omitted.
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Affiliation(s)
- Johannes Muecke
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | - Daniel Reitz
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
- Strahlentherapie Nymphenburg/Fürstenfeldbruck, Munich, Germany
| | - Lili Huang
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | | | - Guillaume Landry
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | - Michael Reiner
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | - Claus Belka
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany
| | | | - Stefanie Corradini
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | - Maximilian Niyazi
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
- Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
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Fan Q, Pham H, Li X, Zhang P, Zhang L, Fu Y, Huang B, Li C, Cuaron J, Cerviño L, Moran JM, Li T. Toward quantitative intrafractional monitoring in paraspinal SBRT using a proprietary software application: clinical implementation and patient results. Phys Med Biol 2024; 69:045015. [PMID: 38241714 DOI: 10.1088/1361-6560/ad2099] [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: 08/31/2023] [Accepted: 01/19/2024] [Indexed: 01/21/2024]
Abstract
Objective.We report on paraspinal motion and the clinical implementation of our proprietary software that leverages Varian's intrafraction motion review (IMR) capability for quantitative tracking of the spine during paraspinal SBRT. The work is based on our prior development and analysis on phantoms.Approach.To address complexities in patient anatomy, digitally reconstructed radiographs (DRR's) that highlight only the spine or hardware were constructed as tracking reference. Moreover, a high-pass filter and first-pass coarse search were implemented to enhance registration accuracy and stability. For evaluation, 84 paraspinal SBRT patients with sites spanning across the entire vertebral column were enrolled with prescriptions ranging from 24 to 40 Gy in one to five fractions. Treatments were planned and delivered with 9 IMRT beams roughly equally distributed posteriorly. IMR was triggered every 200 or 500 MU for each beam. During treatment, the software grabbed the IMR image, registered it with the corresponding DRR, and displayed the motion result in near real-time on auto-pilot mode. Four independent experts completed offline manual registrations as ground truth for tracking accuracy evaluation.Main results.Our software detected ≥1.5 mm and ≥2 mm motions among 17.1% and 6.6% of 1371 patient images, respectively, in either lateral or longitudinal direction. In the validation set of 637 patient images, 91.9% of the tracking errors compared to manual registration fell within ±0.5 mm in either direction. Given a motion threshold of 2 mm, the software accomplished a 98.7% specificity and a 93.9% sensitivity in deciding whether to interrupt treatment for patient re-setup.Significance.Significant intrafractional motion exists in certain paraspinal SBRT patients, supporting the need for quantitative motion monitoring during treatment. Our improved software achieves high motion tracking accuracy clinically and provides reliable guidance for treatment intervention. It offers a practical solution to ensure accurate delivery of paraspinal SBRT on a conventional Linac platform.
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Affiliation(s)
- Qiyong Fan
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Hai Pham
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Xiang Li
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Pengpeng Zhang
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Lei Zhang
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Yabo Fu
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Bohong Huang
- Stony Brook University, Department of Applied Mathematics and Statistics, 100 Nicolls Rd, Stony Brook, NY 11794, United States of America
| | - Cindy Li
- Carnegie Mellon University, Mellon College of Science, 5000 Forbes Ave, Pittsburgh, PA 15213, United States of America
| | - John Cuaron
- Memorial Sloan Kettering Cancer Center, Department of Radiation Oncology, 1275 York Avenue, NY 10065, United States of America
| | - Laura Cerviño
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Jean M Moran
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
| | - Tianfang Li
- Memorial Sloan Kettering Cancer Center, Department of Medical Physics, 1275 York Avenue, NY 10065, United States of America
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Guckenberger M, Dahele M, Ong WL, Sahgal A. Stereotactic Body Radiation Therapy for Spinal Metastases: Benefits and Limitations. Semin Radiat Oncol 2023; 33:159-171. [PMID: 36990633 DOI: 10.1016/j.semradonc.2022.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Progress in biological cancer characterization, targeted systemic therapies and multimodality treatment strategies have shifted the goals of radiotherapy for spinal metastases from short-term palliation to long-term symptom control and prevention of compilations. This article gives an overview of the spine stereotactic body radiotherapy (SBRT) methodology and clinical results of SBRT in cancer patients with painful vertebral metastases, metastatic spinal cord compression, oligometastatic disease and in a reirradiation situation. Outcomes after dose-intensified SBRT are compared with results of conventional radiotherapy and patient selection criteria will be discussed. Though rates of severe toxicity after spinal SBRT are low, strategies to minimize the risk of vertebral compression fracture, radiation induced myelopathy, plexopathy and myositis are summarized, to optimize the use of SBRT in multidisciplinary management of vertebral metastases.
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Hadj Henni A, Gensanne D, Bulot G, Roge M, Mallet R, Colard E, Daras M, Hanzen C, Thureau S. ExacTrac X-Ray 6D Imaging During Stereotactic Body Radiation Therapy of Spinal and Nonspinal Metastases. Technol Cancer Res Treat 2023; 22:15330338231210786. [PMID: 37904530 PMCID: PMC10619343 DOI: 10.1177/15330338231210786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 09/23/2023] [Accepted: 10/12/2023] [Indexed: 11/01/2023] Open
Abstract
The objective was to investigate the possibility of using ExacTrac X-ray (ETX) for 6D image guidance in stereotactic body radiation therapy (SBRT) of bone metastasis and to propose a patient management protocol. The analyses were first obtained from measurements on a pelvic phantom and on 19 patients treated for bone metastasis. The phantom study consisted of applying known offsets and evaluating the ETX level of accuracy, where results were compared with kV-cone beam computed tomography (kV-CBCT). Two groups of patients, 10 spinal and 9 nonspinal SBRT cases, were analyzed to evaluate ETX imaging for different bone localisations. A comparison was made between kV-CBCT and ETX prior to the treatment fractions. During treatments, two other kV-CBCT/ETX image pairs were also acquired and a total of 224 shifts were compared. A second study, using the ETX monitoring module, analyzed the intrafraction motion of 8 other patients. In the phantom study, the root mean square (RMS) of the translational and rotational discrepancies between ETX and kV-CBCT were < 0.6 mm and < 0.4°, respectively. For both groups of patients, the RMS of the discrepancies observed between the two imaging systems were greater than the phantom experiment while still remaining < 1 mm and < 0.7°. In the nonspinal group, three patients (2 scapulas and 1 humerus) did not have consistent shift values with ETX due to a lack of anatomical information. When ETX monitoring was used during irradiation, the setup errors measured were on average less than 1 mm/1°. The results obtained validated the use of ETX for 6D image guidance during bone SBRT. Real-time tracking of the target position improves the accuracy of the irradiation. This strategy allowed for faster correction of out-of-tolerance positioning errors. The registration of bone lesions with poor anatomical information is a limitation of this 2D-kV imaging system.
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Vilotte F, Pasquier D, Blanchard P, Supiot S, Khalifa J, Schick U, Lacornerie T, Vieillevigne L, Marre D, Chapet O, Latorzeff I, Magne N, Meyer E, Cao K, Belkacemi Y, Bibault J, Berge-Lefranc M, Faivre J, Gnep K, Guimas V, Hasbini A, Langrand-Escure J, Hennequin C, Graff P. Recommendations for stereotactic body radiation therapy for spine and non-spine bone metastases. A GETUG (French society of urological radiation oncolgists) consensus using a national two-round modified Delphi survey. Clin Transl Radiat Oncol 2022; 37:33-40. [PMID: 36052019 PMCID: PMC9424259 DOI: 10.1016/j.ctro.2022.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/06/2022] [Indexed: 11/15/2022] Open
Abstract
Background and purpose The relevance of metastasis-directed stereotactic body radiation therapy (SBRT) remains to be demonstrated through phase III trials. Multiple SBRT procedures have been published potentially resulting in a disparity of practices. Therefore, the french society of urological radiation oncolgists (GETUG) recognized the need for joint expert consensus guidelines for metastasis-directed SBRT in order to standardize practice in trials carried out by the group. Materials and methods After a comprehensive literature review, 97 recommendation statements were created regarding planning and delivery of spine bone (SBM) and non-spine bone metastases (NSBM) SBRT. These statements were then submitted to a national online two-round modified Delphi survey among main GETUG investigators. Consensus was achieved if a statement received ≥ 75 % agreements, a trend to consensus being defined as 65-74 % agreements. Any statement without consensus at round one was re-submitted in round two. Results Twenty-one out of 29 (72.4%) surveyed experts responded to both rounds. Seventy-five statements achieved consensus at round one leaving 22 statements needing a revote of which 16 achieved consensus and 5 a trend to consensus. The final rate of consensus was 91/97 (93.8%). Statements with no consensus concerned patient selection (3/19), dose and fractionation (1/11), prescription and dose objectives (1/9) and organs at risk delineation (1/15). The voting resulted in the writing of step-by-step consensus guidelines. Conclusion Consensus guidelines for SBM and NSBM SBRT were agreed upon using a validated modified Delphi approach. These guidelines will be used as per-protocole recommendations in ongoing and further GETUG clinical trials.
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Affiliation(s)
- F. Vilotte
- Department of Radiation Oncology, Institut Bergonié, 229 Cours de l'Argonne, 33076 Bordeaux, France
| | - D. Pasquier
- Department of Radiation Oncology, Centre Oscar Lambret, 3 Rue Frédéric Combemale, 59000 Lille, France
| | - P. Blanchard
- Department of Radiation Oncology, Institut Gustave Roussy, 114 Rue Edouard Vaillant, 94805 Villejuif, France
| | - S. Supiot
- Department of Radiation Oncology, Institut de Cancérologie de L'Ouest, Boulevard Professeur Jacques Monod, 44800 Saint Herblain, France
| | - J. Khalifa
- Department of Radiation Oncology, Institut Universitaire du Cancer de Toulouse-Oncopole, 1 AV Irène Joliot Curie, 31059 Toulouse, France
| | - U. Schick
- Department of Radiation Oncology, CHU de Brest, Hôpital Morvan, avenue Foch, 29200 Brest, France
| | - T. Lacornerie
- Division of Radiation Medical Physics, Centre Oscar Lambret, 3 Rue Frédéric Combemale, 59000 Lille, France
| | - L. Vieillevigne
- Division of Radiation Medical Physics, Institut Universitaire du Cancer de Toulouse-Oncopole, 1 AV Irène Joliot Curie, 31059 Toulouse, France
| | - D. Marre
- Division of Radiation Medical Physics, Groupe ONCORAD Garonne, Clinique Pasteur, Bât Atrium, 1 rue de la petite vitesse, 31300 Toulouse, France
| | - O. Chapet
- Department of Radiation Oncology, CH Lyon Sud 165 Chemin Du Grand Revoyet, 69310 Pierre-bénite, France
| | - I. Latorzeff
- Department of Radiation Oncology, Groupe ONCORAD Garonne, Clinique Pasteur, Bât Atrium, 1 rue de la petite vitesse, 31300 Toulouse, France
| | - N. Magne
- Department of Radiation Oncology, Institut de cancérologie Lucien Neuwirth, 108 bis AV Albert Raimond, 42270 Saint Priest en Jarez, France
| | - E. Meyer
- Department of Radiation Oncology, Centre François Baclesse, 3 Av. du Général Harris, 14000 Caen, France
| | - K. Cao
- Department of Radiation Oncology, Institut Curie Paris, 26 rue d’Ulm, 75005 Paris, France
| | - Y. Belkacemi
- Department of Radiation Oncology, Hôpital Henri-Mondor, 1 rue Gustave Eiffel, 94000 Créteil, France
| | - J.E. Bibault
- Department of Radiation Oncology, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75015 Paris, France
| | - M. Berge-Lefranc
- Department of Radiation Oncology, Centre Saint Michel, rue du Docteur Schweitzer, 17000 La Rochelle, France
| | - J.C. Faivre
- Department of Radiation Oncology, Institut de Cancérologie de Lorraine, 6 Av. de Bourgogne, 54519 Vandœuvre-lès-Nancy, France
| | - K. Gnep
- Department of Radiation Oncology, Centre Eugène Marquis, AV de la Bataille Flandres Dunkerque, 35000 Rennes, France
| | - V. Guimas
- Department of Radiation Oncology, Institut de Cancérologie de L'Ouest, Boulevard Professeur Jacques Monod, 44800 Saint Herblain, France
| | - A. Hasbini
- Department of Radiation Oncology, Clinique Pasteur, 32 r Auguste Kervern, 29200 Brest, France
| | - J. Langrand-Escure
- Department of Radiation Oncology, Institut de cancérologie Lucien Neuwirth, 108 bis AV Albert Raimond, 42270 Saint Priest en Jarez, France
| | - C. Hennequin
- Department of Radiation Oncology, Hôpital Saint Louis, 1 Avenue Claude Vellefaux, 75010 Paris, France
| | - P. Graff
- Department of Radiation Oncology, Institut Curie Saint Cloud, 35 rue Dailly, 92210 Saint Cloud, France
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He X, Cai W, Li F, Fan Q, Zhang P, Cuaron JJ, Cerviño LI, Li X, Li T. Decompose kV projection using neural network for improved motion tracking in paraspinal SBRT. Med Phys 2021; 48:7590-7601. [PMID: 34655442 DOI: 10.1002/mp.15295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/23/2021] [Accepted: 09/29/2021] [Indexed: 01/03/2023] Open
Abstract
PURPOSE On-treatment kV images have been used in tracking patient motion. One challenge of markerless motion tracking in paraspinal SBRT is the reduced contrast when the X-ray beam needs to pass through a large portion of the patient's body, for example, from the lateral direction. Besides, due to the spine's overlapping with the surrounding moving organs in the X-ray images, auto-registration could lead to potential errors. This work aims to automatically extract the spine component from the conventional 2D X-ray images, to achieve more robust and more accurate motion management. METHODS A ResNet generative adversarial network (ResNetGAN) consisting of one generator and one discriminator was developed to learn the mapping between 2D kV image and the reference spine digitally reconstructed radiograph (DRR). A tailored multi-channel multi-domain loss function was used to improve the quality of the decomposed spine image. The trained model took a 2D kV image as input and learned to generate the spine component of the X-ray image. The training dataset included 1347 2D kV thoracic and lumbar region X-ray images from 20 randomly selected patients, and the corresponding matched reference spine DRR. Another 226 2D kV images from the remaining four patients were used for evaluation. The resulted decomposed spine images and the original X-ray images were registered to the reference spine DRRs, to compare the spine tracking accuracy. RESULTS The decomposed spine image had the mean peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) of 60.08 and 0.99, respectively, indicating the model retained and enhanced the spine structure information in the original 2D X-ray image. The decomposed spine image matching with the reference spine DRR had submillimeter accuracy (in mm) with a mean error of 0.13, 0.12, and a maximum of 0.58, 0.49 in the x - and y -directions (in the imager coordinates), respectively. The accuracy improvement is robust in all lateral and anteroposterior X-ray beam angles. CONCLUSION We developed a deep learning-based approach to remove soft tissues in the kV image, leading to more accurate spine tracking in paraspinal SBRT.
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Affiliation(s)
- Xiuxiu He
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Weixing Cai
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Feifei Li
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Qiyong Fan
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Pengpeng Zhang
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - John J Cuaron
- Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Laura I Cerviño
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Xiang Li
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
| | - Tianfang Li
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, USA
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Rossi E, Fiorino C, Fodor A, Deantoni C, Mangili P, Di Muzio NG, Del Vecchio A, Broggi S. Residual intra-fraction error in robotic spinal stereotactic body radiotherapy without immobilization devices. Phys Imaging Radiat Oncol 2020; 16:20-25. [PMID: 33458339 PMCID: PMC7807594 DOI: 10.1016/j.phro.2020.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/11/2020] [Accepted: 09/23/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Spinal stereotactic body radiotherapy (SBRT) involves large dose gradients and high geometrical accuracy is therefore required. The aim of this work was to assess residual intra-fraction error with a tracking robotic system for non-immobilized patients. Shifts from the first alignment (i.e. mimicking the unavailability of tracking) were also quantified. MATERIALS AND METHODS Forty-two patients treated for spinal metastasis (128 fractions, 4220 images) were analyzed. Residual error was quantified as the difference between translations/rotations referring to consecutive x-ray images during delivery (tracking) and to the initial set-up (no-tracking). The error distribution for each fraction/patient and the entire population was assessed for each axis/rotation angle. The impact of lesion sites, fractionation and patient's pain (VAS score) were investigated. Finally, the dosimetric impact of residual motion was quantified in the four most affected fractions. RESULTS Mean overall errors (OE) were near 0 (SD < 0.1 mm). Residual translations/rotations >1 mm/1° were found in less than 1.5%/1% of measurements. Lesion site and fractionation showed no impact. The dosimetric impact in the most affected fractions was negligible. For "no-tracking", mean OE was <1 mm/0.5°; less than 2% of displacements were >2 mm/1° within 10 min from the start of treatment with an increasing probability of shifts >2 mm over time. A significantly higher fraction of OE ≥ 2 mm was found for patients with pain in case of no-tracking. CONCLUSIONS Spine tracking with a latest-generation robotic system is highly efficient for non-immobilized patients: residual error is time independent and close to 0. For delivery times >7-8 min, tracking should be considered as mandatory for non-immobilized patients.
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Affiliation(s)
- Eleonora Rossi
- Medical Physics, San Raffaele Scientific Institute, Milano, Italy
| | - Claudio Fiorino
- Medical Physics, San Raffaele Scientific Institute, Milano, Italy
| | - Andrei Fodor
- Radiotherapy, San Raffaele Scientific Institute, Milano, Italy
| | - Chiara Deantoni
- Radiotherapy, San Raffaele Scientific Institute, Milano, Italy
| | - Paola Mangili
- Medical Physics, San Raffaele Scientific Institute, Milano, Italy
| | | | | | - Sara Broggi
- Medical Physics, San Raffaele Scientific Institute, Milano, Italy
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