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aSi-EPID transit signal calibration for dynamic beams: a needful step for the IMRT in vivo dosimetry

Francesca Greco, Angelo Piermattei, Luigi Azario, Lorenzo Placidi, Savino Cilla, Rocchina Caivano, Vincenzo Fusco, Andrea Fidanzio
2013 Medical and Biological Engineering and Computing  
This work reports a method based on correlation functions to convert EPID transit signals into in vivo dose values at the isocenter point, D iso , of dynamic IMRT beams supplied by Varian linac.  ...  The in vivo dosimetry procedure here presented is among the objectives of a National Project financially supported by the Istituto Nazionale di Fisica Nucleare for the development of in vivo dosimetry  ...  Transit dosimetry Simulated IMRT beams The approach the authors have been pursuing over the years is to generate look up factors to convert transit signal by EPIDs into dose values on the beam central  ... 
doi:10.1007/s11517-013-1094-x pmid:23835663 pmcid:PMC3751319 fatcat:qflks273brbphgmnrrq3ypuocy

Verification of the delivered patient radiation dose for non‐coplanar beam therapy

Ivan Kutuzov, Timothy Van Beek, Boyd M.C. McCurdy
2021 Journal of Applied Clinical Medical Physics  
In this work, new functionality that allows using non-coplanar beam arrangements in addition to conventional coplanar beams was added and validated to the previously developed in vivo dose verification  ...  The chi-comparison test resulted in at least a 97.0% pass rate over the entire 3D volume for all tested trajectories.  ...  Ideally when in vivo dosimetry is implemented with transmission EPID imaging, no additional time will be needed.  ... 
doi:10.1002/acm2.13280 pmid:34021713 fatcat:kb7rebtoznb7bhfdkcojdborby

The use of EPID-measured leaf sequence files for IMRT dose reconstruction in adaptive radiation therapy

Louis Lee, Weihua Mao, Lei Xing
2008 Medical Physics (Lancaster)  
This paper presents a proof of feasibility and principles in ͑1͒ using an amorphous silicon electronic portal imaging device ͑aSi-EPID͒ to capture the MLC segments during an IMRT delivery and ͑2͒ reconstituting  ...  The EPID-measured LS file can serve the same purpose as a MLC log files does for the derivation of the delivered fluence map and yet is independent of the leaf calibration.  ...  For instance, in IMRT using step-andshoot mode, the expected delivery of fluence maps might not be realized due to intrinsic errors associated with the multileaf collimator ͑MLC͒ kinematics and beam control  ... 
doi:10.1118/1.2990782 pmid:19070236 pmcid:PMC2737246 fatcat:72yecaattvhg3d6wx4xo2nlyt4

Two-dimensionalin vivodose verification using portal imaging and correlation ratios

Stefano Peca, Derek W. Brown
2014 Journal of Applied Clinical Medical Physics  
The electronic portal imaging device (EPID) has the potential to be used for in vivo dosimetry during radiation therapy as an additional dose delivery check.  ...  This 2D EPID-based in vivo dosimetry method can be used for posttreatment dose verification, thereby improving the safety and quality of patient treatments.  ...  As well, we acknowledge Kurt Knibutat for help in image acquisition and Darren Graham for beam planning. rEFErEncES  ... 
doi:10.1120/jacmp.v15i4.4752 pmid:25207402 pmcid:PMC5875516 fatcat:2nvmzbt3w5eqjhhko6at6mh7xu

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  
We evaluated an EPID-based in-vivo dosimetry (IVD) method for the dose verification and the treatment reproducibility of lung SBRT-VMAT treatments in clinical routine.  ...  Alert criteria of ±5% for R ratio, γ % < 90%, and γ mean > 0.67 were chosen. 50 transit EPID images were acquired.  ...  In other words, the first portal image was used as a surrogate of EPID transit signals to ensure the highest treatment reproducibility.  ... 
doi:10.1002/acm2.12538 fatcat:bgob4gxzjzbyxmc6cegaczarnu

A Model for Online Interactive Remote Education for Medical Physics Using the Internet

Milton K Woo, Kwan-Hoong Ng
2003 Journal of Medical Internet Research  
The present skin dose study shows that MOSFET is a dosimeter suitable for in-vivo dosimetry in dynamic as well as universal wedge photon beams.  ...  of leaf positions is a key step in IMRT.  ...  Additionally, the dynamic range will be demonstrated as a function of input dose level.  ... 
doi:10.2196/jmir.5.1.e3 pmid:12746208 pmcid:PMC1550549 fatcat:tsyf45yusza2jiglkq62rgo3qm

TU-B-I-617-01: High Field MRI - Technology, Applications, Safety, and Limitations

RJ Stafford
2005 Medical Physics (Lancaster)  
HD-810 films were calibrated in a 60 Co beam.  ...  The standard deviation of the distribution decreased to < 1 cGy after 6 fractions for motion in the M-L and S-I directions for step-and-shoot IMRT delivery and 7 fractions for dynamic arc delivery.  ...  We propose using the aSi EPID 2D-density distribution to replace the chamber/film for MLC QA, and to verify the dosimetry and mechanics of the MLC for IMRT.  ... 
doi:10.1118/1.1999700 fatcat:yub56igoe5cl3cthdpzwrdvjp4

SU-EE-A3-06: An Efficient Algorithm for Image-Based Dose Deformation and Accumulation

M Kaus, V Pekar, T McNutt, K Bzdusek
2005 Medical Physics (Lancaster)  
HD-810 films were calibrated in a 60 Co beam.  ...  The standard deviation of the distribution decreased to < 1 cGy after 6 fractions for motion in the M-L and S-I directions for step-and-shoot IMRT delivery and 7 fractions for dynamic arc delivery.  ...  We propose using the aSi EPID 2D-density distribution to replace the chamber/film for MLC QA, and to verify the dosimetry and mechanics of the MLC for IMRT.  ... 
doi:10.1118/1.1997464 fatcat:zue2hfmc5ze6ziwu332w3u2lue

TU-EE-A3-05: Scatter Radiation in Digital Tomosynthesis

B Liu, S Glick, X Gong
2005 Medical Physics (Lancaster)  
HD-810 films were calibrated in a 60 Co beam.  ...  The standard deviation of the distribution decreased to < 1 cGy after 6 fractions for motion in the M-L and S-I directions for step-and-shoot IMRT delivery and 7 fractions for dynamic arc delivery.  ...  We propose using the aSi EPID 2D-density distribution to replace the chamber/film for MLC QA, and to verify the dosimetry and mechanics of the MLC for IMRT.  ... 
doi:10.1118/1.1998434 fatcat:jnqebvqstnhixdmecqmh35gfbi

AAPM Spring Clinical Meeting - Abstract

2021 Journal of Applied Clinical Medical Physics  
A simple step-by-step setup checks minimizing these five factors can help ensure the quality and consistency of remote reading.  ...  IMRT QA using portal dosimetry confirmed there are no significant delivery issues with the HyperArc plans. , CARTI, Little Rock, AR Purpose: In version 15.5, Eclipse TPS from Varian introduced a new option  ...  Conclusion: This study provides a progressive step towards verifying dose delivery during radiation therapy treatments by exploring the reemitted Cherenkov signal in real-time.  ... 
doi:10.1002/acm2.13289 pmid:34002941 fatcat:6oivewssf5gwnnztmhff4nldle

Transit Dosimetry for Patient Treatment Verification with an Electronic Portal Imaging Device

Sean Lawrence Berry
2017
Amorphous silicon (aSi) Electronic Portal Imaging Devices (EPIDs) can be utilized for IMRT verification.  ...  The goal of this thesis is to implement EPID transit dosimetry, measurement of the dose at a plane behind the patient during their treatment, within the clinical process.  ...  ACKNOWLEDGEMENTS It is only through the support and encouragement of numerous people that the completion of a Ph.D. program and a doctoral thesis can be accomplished.  ... 
doi:10.7916/d8794brt fatcat:kjldsxncbzgm5gr574m6rfluly

Development and Clinical Application of a New Two-Dimensional in vivo Dosimetry by Electronic Portal Imaging [article]

Stefano Peca, University Of Calgary, University Of Calgary, Wendy Smith, Derek Brown
2017
In this thesis I describe a novel method of using the electronic portal imaging device (EPID) for IVD. Images are measured through phantoms/patients making use of treatment beams.  ...  In vivo dosimetry (IVD) in radiotherapy refers to direct measurement of dose deposited in the patient during treatment.  ...  Acknowledgements The cliché phrase "this thesis would not have been possible if not for the help of…" has Acknowledgment We are grateful to Analyse-it (Leeds, UK) for providing a free license which enabled  ... 
doi:10.11575/prism/25639 fatcat:rvkmyimyjfceth3u2oogrzrqzi

An electronic portal image-based monte carlo approach to in-vivo dosimetry for intensity modulated radiation therapy

Parmveer Singh Atwal
2009
Unfortunately, some sources of delivery errors, such as mis-calibration of the beam-modulating system, cannot be easily incorporated in the model.  ...  Use of the amorphous-silicon detector (or EPID, for Electronic Portal Imaging Device), available on many linear accelerators, provides a solution.  ...  Agronivich was able to obtain funding for this work from Sanofi Aventis Canada, and I am truly grateful for the opportunity they provided me to do research in medical physics.  ... 
doi:10.14288/1.0067746 fatcat:ofnq5ogjenf4tawxkr75qkm3ay