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A limited-angle intrafraction verification (LIVE) system for radiation therapy

Lei Ren, You Zhang, Fang-Fang Yin
2014 Medical Physics (Lancaster)  
With this improvement, LIVE opens up a Ren, Zhang, and Yin: Limited-angle intrafraction verification (LIVE) system for radiation therapy 020701-2 new avenue for margin reduction and dose escalation in  ...  is critical for stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) treatments.  ...  In our study, a dynamic conformal arc treatment plan was made to deliver conformal dose to the PTV.  ... 
doi:10.1118/1.4861820 pmid:24506590 fatcat:cbcuzs2wbvekfajt7regs2dylm

Assessing the Dosimetric Impact of Real-Time Prostate Motion During Volumetric Modulated Arc Therapy

Juan Diego Azcona, Lei Xing, Xin Chen, Karl Bush, Ruijiang Li
2014 International Journal of Radiation Oncology, Biology, Physics  
during volumetric modulated arc therapy (VMAT).  ...  Purpose-To develop a method for dose reconstruction by incorporating the interplay effect between aperture modulation and target motion, and to assess the dosimetric impact of real-time prostate motion  ...  The combined procedure for dose reconstruction including motion and delivery parameters would be a useful tool for adaptive radiation therapy.  ... 
doi:10.1016/j.ijrobp.2013.12.015 pmid:24661670 pmcid:PMC4088267 fatcat:kiwtehbzwrbw5dw57vlbuqyjwy

A comprehensive EPID-based 3D validation technique for TrueBeam-delivered VMAT plans

W Ansbacher, I M Gagne, C-L Swift
2014 Journal of Physics, Conference Series  
Results: Approximately 60 portal image projections per arc were found to be adequate for 3D reconstruction in phantom volumes of 28cm diameter.  ...  Purpose: To develop and validate a pre-treatment EPI dosimetry method on Varian TrueBeam linacs using continuous imaging, with reconstruction in a 3D cylindrical phantom geometry.  ...  We would like to thank Vince LaPointe, BCCA Vancouver Centre, for initial work on Research mode, and Thanos Etmektzoglu, Varian Medical Systems, for assistance with xml scripting.  ... 
doi:10.1088/1742-6596/489/1/012067 fatcat:kgtad25dmrawje7bqwo5u2oj4e

Automatic Prostate Tracking and Motion Assessment in Volumetric Modulated Arc Therapy With an Electronic Portal Imaging Device

Juan Diego Azcona, Ruijiang Li, Edward Mok, Steven Hancock, Lei Xing
2013 International Journal of Radiation Oncology, Biology, Physics  
Purpose-To assess the prostate intrafraction motion in volumetric modulated arc therapy treatments using cine megavoltage (MV) images acquired with the electronic portal imaging device (EPID).  ...  Materials and methods-Ten prostate cancer patients were treated with volumetric modulated radiation therapy (VMAT), using a Varian TrueBeam (Varian Medical Systems, Palo Alto, CA) linear accelerator (linac  ...  radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT).  ... 
doi:10.1016/j.ijrobp.2013.03.007 pmid:23608236 pmcid:PMC3686883 fatcat:gu5simty7rbwjc2eiduad4liu4

EP-1493: Dosimetric and geometric verification with the moving phantom of gating stereotactic lung treatment

C. Ceylan, A. Kiliç, H. Ayata, T. Ugur, M. Güden, K. Engin
2015 Radiotherapy and Oncology  
Initial results also suggest a reduction in LAD mean and maximum doses for patients treated in DIBH (figure 1). Further results will be described. Table 1. Comparison of LAD doses in DIBH vs.  ...  We have demonstrated this on data from a software phantom and real dynamic MRI, 4DCT, and Cine CT lung data, achieving good results in all cases.  ...  Initial results also suggest a reduction in LAD mean and maximum doses for patients treated in DIBH (figure 1). Further results will be described.  ... 
doi:10.1016/s0167-8140(15)41485-9 fatcat:zuvnpwj3czbrlcbwrwrzjnlvye

Clinical Study of Orthogonal-View Phase-Matched Digital Tomosynthesis for Lung Tumor Localization

You Zhang, Lei Ren, Irina Vergalasova, Fang-Fang Yin
2017 Technology in Cancer Research and Treatment  
in radiation therapy.  ...  Phantom studies were also performed using an anthropomorphic phantom to investigate the feasibility of using intratreatment aggregated kV and beams' eye view cine MV projections for orthogonal-view phase-matched  ...  Based on the AIP image, a 150 dynamic conformal arc plan was designed in Eclipse (Varian Medical Systems, Palo Alto, California; Figure 6 ).  ... 
doi:10.1177/1533034617705716 pmid:28449625 pmcid:PMC5547009 fatcat:xydeifvpifcqzju2kpzzeifhyy

Imaging and dosimetric errors in 4D PET/CT-guided radiotherapy from patient-specific respiratory patterns: a dynamic motion phantom end-to-end study

S R Bowen, M J Nyflot, C Herrmann, C M Groh, J Meyer, S D Wollenweber, C W Stearns, P E Kinahan, G A Sandison
2015 Physics in Medicine and Biology  
Non-uniform dose-painting plans using volumetrically modulated arc therapy (VMAT) were optimized for fixed normal lung and spinal cord objectives and variable PET-based target objectives.  ...  An end-to-end workflow was developed to measure patient-specific motion-induced uncertainties in imaging, treatment planning, and radiation delivery with respiratory motion phantoms and dosimeters.  ...  Acknowledgments This work was supported by NIH grant 5P30 CA015704, a research contract from GE Healthcare (Waukesha, WI), and a grant from the Bavarian Research Foundation (Germany).  ... 
doi:10.1088/0031-9155/60/9/3731 pmid:25884892 pmcid:PMC4425357 fatcat:375xu3dkmbaxtmd5j76cbvdr7a

Towards fast online intrafraction replanning for free-breathing stereotactic body radiation therapy with the MR-linac

C Kontaxis, G H Bol, B Stemkens, M Glitzner, F M Prins, L G W Kerkmeijer, J J W Lagendijk, B W Raaymakers
2017 Physics in Medicine and Biology  
In this work we present a proof of principle adaptive pipeline designed for high precision stereotactic body radiation therapy (SBRT) suitable for sites affected by respiratory motion, like renal cell  ...  The simulated pipeline included a combination of (prebeam) 4D-MRI and (online) 2D cine-MR acquisitions.  ...  The authors would like to thank Elekta AB, Stockholm, Sweden for providing some of their research software tools.  ... 
doi:10.1088/1361-6560/aa82ae pmid:28749375 fatcat:me4pxqstlvdybkcipzftpea7dq

Reducing scan angle using adaptive prior knowledge for a limited-angle intrafraction verification (LIVE) system for conformal arc radiotherapy

Yawei Zhang, Fang-Fang Yin, You Zhang, Lei Ren
2017 Physics in Medicine and Biology  
The LIVE system has been previously developed to reconstruct 4D volumetric images on-the-fly during arc treatment for intrafraction target verification and dose calculation.  ...  The 4D digital extended-cardiac-torso (XCAT) phantom and a CIRS 008A dynamic thoracic phantom were used to evaluate the effectiveness of this technique.  ...  Acknowledgments This work was supported by the National Institutes of Health under Grant No R01-CA184173 and a research grant from Varian Medical Systems, and the K40 GPU used in this work were donated  ... 
doi:10.1088/1361-6560/aa6913 pmid:28338470 pmcid:PMC5543931 fatcat:hbiqmjj3g5a4hgn4wc7kvemg4a

Accuracy Comparison of 4D Computed Tomography (4DCT) and 4D Cone Beam Computed Tomography (4DCBCT)

Tzu-Cheng Lee, Stephen R. Bowen, Sara St. James, George A. Sandison, Paul E. Kinahan, Matthew J. Nyflot
2017 International Journal of Medical Physics Clinical Engineering and Radiation Oncology  
lung stereotactic body radiation therapy (SBRT) and other motion-managed therapies.  ...  A programmable respiratory motion phantom was used to simulate the 1D S-I position of a known-size lesion.  ...  Acknowledgement Supported in part by NIH grant R01 CA160253.  ... 
doi:10.4236/ijmpcero.2017.63029 fatcat:gedq2fnii5ffzikqfvqyth6zgi

Pixel response-based EPID dosimetry for patient specific QA

Bin Han, Aiping Ding, Minghui Lu, Lei Xing
2016 Journal of Applied Clinical Medical Physics  
After the raw image was converted into the primary incident photon fluence, the fluence was further convolved into a water-based dose distribution of the dynamic field by using a pregenerated pencil-beam  ...  The high spatial resolution and high frame rate EPID provides an accurate and efficient dosimetric tool for QA of modern radiation therapy.  ...  Asuni et al. 9 and Lee et al. 10 used EPID images to reconstruct in vivo 3D dose for Stereotactic Body Radiation Therapy (SBRT) QA.  ... 
doi:10.1002/acm2.12007 pmid:28291939 pmcid:PMC5393354 fatcat:eam3235eyfgizasxertj4chhmu

Epid-based in vivo dose verification for lung stereotactic treatments delivered with multiple breath-hold segmented volumetric modulated arc therapy

Savino Cilla, Anna Ianiro, Maurizio Craus, Pietro Viola, Francesco Deodato, Gabriella Macchia, Milly Buwenge, Alessio G. Morganti, Vincenzo Valentini, Angelo Piermattei
2019 Journal of Applied Clinical Medical Physics  
For the patients treated with ABC spirometer, the results reported a high level of accuracy in dose delivery with 100% of tests within ±5%.  ...  Our method provided a fast and accurate procedure in clinical routine for verifying delivered dose as well as for detecting errors.  ...  Our previous research 41 reported the feasibility to obtain the "real-time" isocenter dose in dynamic conformal arc therapy using the signal supplied by an EPID cine acquisition mode every 1.66 s during  ... 
doi:10.1002/acm2.12538 fatcat:bgob4gxzjzbyxmc6cegaczarnu

Emerging Role of MRI for Radiation Treatment Planning in Lung Cancer

David C. P. Cobben, Hans C. J. de Boer, Rob H. Tijssen, Emma G. G. M. Rutten, Marco van Vulpen, Jurgen Peerlings, Esther G. C. Troost, Aswin L. Hoffmann, Astrid L. H. M. W. van Lier
2016 Technology in Cancer Research and Treatment  
This review describes the opportunities and challenges of magnetic resonance imaging for radiation treatment planning in lung cancer.  ...  Moreover, it offers the potential for real-time motion imaging. This makes magnetic resonance imaging an ideal candidate imaging modality for radiation treatment planning in lung cancer.  ...  radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT).  ... 
doi:10.1177/1533034615615249 pmid:26589726 fatcat:uokxzcft3zcofahb6gyixcku3y

EPID based in vivo dosimetry system: clinical experience and results

Sofia Celi, Emilie Costa, Claas Wessels, Alejandro Mazal, Alain Fourquet, Pascal Francois
2016 Journal of Applied Clinical Medical Physics  
The 3D conformal treatment plans had a mean dose difference of 2.0% (± 4.9%), while for intensity-modulated radiotherapy and volumetric-modulated arc therapy treatments the mean dose difference was -3.0  ...  volumetric-modulated arc therapy.  ...  C.2 Static IMRT and dynamic arc therapy: prostate cancer cases For IMRT and dynamic arc therapy, transit dosimetry represents an important progress in comparison with classic IVD, where the measurement  ... 
doi:10.1120/jacmp.v17i3.6070 pmid:27167283 pmcid:PMC5690938 fatcat:ux5l564ztfggnjprrpwqzhoqdu

Radiosurgical third ventriculostomy: Technical note

GuillermoAxayacalt Gutiérrez-Aceves, Sergio Moreno-Jiménez, MiguelÁngel Celis, Mariana Hernández-Bojórquez
2012 Surgical neurology international  
A series of 21 arcs was arranged with a radiation field generated by a 4 mm circular collimator.  ...  The patient received radiosurgical treatment for brain metastasis; after this procedure a new target was defined on the floor of the third ventricle, in the midpoint between the mamillary bodies and the  ...  acquisition through the target point (axial and coronal plane reconstructions), showing the dose distribution of the 4 mm collimator arcs arrangement including the contributions of the metastasis single  ... 
doi:10.4103/2152-7806.102338 pmid:23226607 pmcid:PMC3512342 fatcat:ldl5le4n6jep5b5663agsspd3m
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