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The predictive value of segmentation metrics on dosimetry in organs at risk of the brain

Robert Poel, Elias Rüfenacht, Evelyn Herrmann, Stefan Scheib, Peter Manser, Daniel M. Aebersold, Mauricio Reyes
In this study, we present results investigating the correlation between popular geometric segmentation metrics and dose parameters for Organs-At-Risk (OAR) in brain tumor patients, and investigate properties  ...  that might be predictive for dose changes in brain radiotherapy.  ...  Acknowledgement This work was supported by Innosuisse grant number 31274.1 and the Swiss Cancer League.  ... 
doi:10.48350/158387 fatcat:isanwoyyabaw7kxurfevu76gom

iPhantom: a framework for automated creation of individualized computational phantoms and its application to CT organ dosimetry [article]

Wanyi Fu, Shobhit Sharma, Ehsan Abadi, Alexandros-Stavros Iliopoulos, Qi Wang, Joseph Y. Lo, Xiaobai Sun, William P. Segars, Ehsan Samei
2020 arXiv   pre-print
Result: iPhantom was validated on both the XCAT (n=50) and an independent clinical (n=10) dataset with similar accuracy. iPhantom precisely predicted all organ locations with good accuracy of Dice Similarity  ...  The framework is applied to assess radiation dose to radiosensitive organs in CT imaging of individual patients.  ...  layers to preserve the size and information. The last layer is a Softmax function, with the number of the output set as the number of anchor organs types.  ... 
arXiv:2008.08730v1 fatcat:6loo5tutbvarbbf5ebbgmvwj6e

Analysis of Geometric Performance and Dosimetric Impact of Using Automatic Contour Segmentation for Radiotherapy Planning

Minsong Cao, Bradley Stiehl, Victoria Y. Yu, Ke Sheng, Amar U. Kishan, Robert K. Chin, Yingli Yang, Dan Ruan
2020 Frontiers in Oncology  
brain, to 0.36 for the chiasm of the HN group.  ...  Conclusion: Varying AS performance among structures suggests a differential approach of using AS on a subset of structures and focus MS on the rest.  ...  INTRODUCTION Accurate and efficient contouring is essential to the quality of treatment planning in radiation therapy because incorrect delineation of the target volume and organs at risk (OARs) can lead  ... 
doi:10.3389/fonc.2020.01762 pmid:33102206 pmcid:PMC7546883 fatcat:w5wskk66lfgd3jq6paoqgvyjsu

The promise of artificial intelligence and deep learning in PET and SPECT imaging

Hossein Arabi, Azadeh AkhavanAllaf, Amirhossein Sanaat, Isaac Shiri, Habib Zaidi
2021 Physica medica (Testo stampato)  
Finally, the challenges, opportunities, and barriers to full-scale validation and adoption of AI-based solutions for improvement of image quality and quantitative accuracy of PET and SPECT images in the  ...  This review sets out to discuss the foremost applications of artificial intelligence (AI), particularly deep learning (DL) algorithms, in single-photon emission computed tomography (SPECT) and positron  ...  Acknowledgments This work was supported by the Swiss National Science Foundation under grant SNRF 320030_176052 and the Private Foundation of Geneva University Hospitals under grant RC-06-01.  ... 
doi:10.1016/j.ejmp.2021.03.008 pmid:33765602 fatcat:onw4fm22y5cxndxiwyy5bdw4t4

OC-0522 Characterising dose changes due to unplanned gas cavities in Magnetic Resonance guided Radiotherapy

J. Shortall, E. Vasquez Osorio, A. Green, R. Chuter, A. McWilliam, K. Kirkby, R. Mackay, M. Van Herk
2019 Radiotherapy and Oncology  
In addition to dosimetry metrics, delivery parameters including treatment plan geometry, delivery time and monitor units were analysed for the top 50 plans.  ...  Figure 1: Waterfall plot of plan scores for the top 50 plans with delivery or planning technique denoted by colour Figure 2: (a) 100% CI (b) 50% CI (c) volume of normal brain receiving 12 Gy and (d) delivery  ...  Little work has been done on characterising the dosimetric effects of unplanned gas cavities in MRgRT on Organs At Risk (OAR), which could affect their dose constraints, depending on beam directions and  ... 
doi:10.1016/s0167-8140(19)30942-9 fatcat:635cux65qfbl7gbzvrs22i2wl4

Use of Normal Tissue Complication Probability Models in the Clinic

Lawrence B. Marks, Ellen D. Yorke, Andrew Jackson, Randall K. Ten Haken, Louis S. Constine, Avraham Eisbruch, Søren M. Bentzen, Jiho Nam, Joseph O. Deasy
2010 International Journal of Radiation Oncology, Biology, Physics  
A summary of organ-specific dose/volume/outcome data, based on the QUANTEC reviews, is included.  ...  A "clinician's view" on using the QUANTEC information in a responsible manner is presented along with a description of the most commonly-used normal tissue complication probability (NTCP) models.  ...  Acknowledgments Special thanks to Jessica Hubbs for her assistance in the preparation of this manuscript.  ... 
doi:10.1016/j.ijrobp.2009.07.1754 pmid:20171502 pmcid:PMC4041542 fatcat:w72fmkchxvehdalmoex7u2to5m

Neurotoxic and pharmacokinetic responses to trichloroethylene as a function of exposure scenario

W K Boyes, P J Bushnell, K M Crofton, M Evans, J E Simmons
2000 Environmental Health Perspectives  
For the acute effects of TCE on behavior and visual function, the estimated concentration of TCE in blood at the time of testing correlated well with outcomes, whereas cumulative exposure, measured as  ...  Examination of all three measures of neurotoxicity showed that if Haber's Rule were used to predict outcomes across exposure durations, the risk would be overestimated when extrapolating from shorter to  ...  TCEA was chosen as the dose metric because of its close relationship to target organ (brain) concentration and because of the ready accessibility of blood from experimental animals.  ... 
doi:10.1289/ehp.00108s2317 pmid:10807561 pmcid:PMC1637762 fatcat:2qzdcayaw5fk3nchw3glh2ixiu

Development and Validation of an Age-Scalable Cardiac Model with Substructures for Dosimetry in Late-Effects Studies of Childhood Cancer Survivors

Suman Shrestha, Aashish C. Gupta, James E. Bates, Choonsik Lee, Constance A. Owens, Bradford S. Hoppe, Louis S. Constine, Susan A. Smith, Ying Qiao, Rita E. Weathers, Yutaka Yasui, Laurence E. Court (+6 others)
2020 Radiotherapy and Oncology  
In order to develop substructure dose-response models, the heart model previously used for pediatric cohort dosimetry needed enhancement and substructure delineation.  ...  Emerging data suggest that dose to cardiac substructures may be more predictive than whole heart metrics.  ...  Sarah Bronson from Scientific Publications, Research Medical Library, The University of Texas MD Anderson Cancer Center, for assistance in editing this manuscript.  ... 
doi:10.1016/j.radonc.2020.10.017 pmid:33075392 pmcid:PMC8132170 fatcat:o2vmort2uzejjbxksedcogfe4m

Overview of the First NRG-NCI Workshop on Dosimetry of Systemic Radiopharmaceutical Therapy (RPT)

Emilie Roncali, Jacek Capala, Stanley H Benedict, Gamal Akabani, Bryan Bednarz, Vikram Bhadrasain, Wesley E. Bolch, Jeff Buchsbaum, Bonnie N. Clarke, Norman Coleman, Yuni K Dewaraja, Eric C. Frey (+18 others)
2020 Journal of Nuclear Medicine  
In this proceedings, we review the main approaches that are applied clinically to calculate the absorbed dose: These include absorbed doses calculated over a variety of spatial scales including organ,  ...  strategies of dosimetry for future clinical trials.  ...  This often results in uncertainties in the reporting of the resulting absorbed dose delivered to the tumor volumes and the normal organs including organs at risk given individual patient pharmacokinetics  ... 
doi:10.2967/jnumed.120.255547 pmid:33277396 pmcid:PMC8833877 fatcat:72h636ohqfhqtjd5sviouls65y

Novel Clinically Weight-Optimized Dynamic Conformal Arcs (WO-DCA) for Liver SBRT: A Comparison with Volumetric Modulated Arc Therapy (VMAT)

Yucel Saglam, Yasemin Bolukbasi, Ali Ihsan Atasoy, Fatih Karakose, Mustafa Budak, Vildan Alpan, Erkan Topkan, Ugur Selek
2021 Therapeutics and Clinical Risk Management  
Weight of the two arcs using optimization method was adjusted between the arcs to maximize tumor coverage and protect organs at risk (OAR) based on the RTOG-0438 protocol.  ...  Similarly, the WO-DCA technique additionally reduced the beam-on time (3.26 vs 4.43; P < 0.001) and monitor unit (1860 vs 2705 for VMAT; P < 0.001) values significantly.  ...  to the target volume while sparing healthy liver tissue and the organs at risk (OAR) with extraordinary sensitivity and low toxicity profile, 6-10 specifically with a mild acceptable risk of radiation-induced  ... 
doi:10.2147/tcrm.s328375 pmid:34611405 pmcid:PMC8487279 fatcat:sfmdxk66bvfonnqek42wehaxj4

Impact of the accuracy of automatic tumour functional volume delineation on radiotherapy treatment planning

Amandine Le Maitre, Mathieu Hatt, Olivier Pradier, Catherine Cheze-le Rest, Dimitris Visvikis
2012 Physics in Medicine and Biology  
The different algorithms and resulting plans were compared in terms of segmentation errors and ground-truth volume coverage using different metrics (V 95 , D 95 , homogeneity index and conformity index  ...  The objective of this study is to compare different methods in terms of dosimetry. For such comparison, a gold-standard is needed. For this purpose realistic GATE simulated PET images were used.  ...  The constraints to the organs at 180 risk (OARs) considered for the IMRT plans are summarized in Tables 1 and 2.  ... 
doi:10.1088/0031-9155/57/17/5381 pmid:22864012 fatcat:ek2qlbnzjbafhipiny7eslpury

Verification of IMRT and RapidArc Localized Prostate Cancer Treatment Plans Using EPID and Delta4 in vivo Dosimetry Methods

Moustafa Ahmed, Naer Baker, Khaled El-Shahat, Mohamed Akl, Ahmed Shawata
2021 Middle East Journal of Cancer  
Quality assurance for intensity modulated radiation therapy (IMRT) depends on the type of dosimetry system and its evaluation procedure.  ...  Delta4 dosimetry system was assessed with RapidArc plan; the agreement between the measured and planned doses was ±1% and gamma analysis resulted in 100% data points with the same agreement conditions.  ...  Acknowledgments All of the authors would like to thank the anonymous reviewers for their helpful comments on the original manuscript.  ... 
doi:10.30476/mejc.2020.84706.1226 doaj:13b173f086ff4b9c9d958727f1b53b75 fatcat:shqcsjkmc5fbhjsmfdsk645sey

Internal radiation dosimetry of a 152Tb-labeled antibody in tumor-bearing mice

Francesco Cicone, Silvano Gnesin, Thibaut Denoël, Thierry Stora, Nicholas P. van der Meulen, Cristina Müller, Christiaan Vermeulen, Martina Benešová, Ulli Köster, Karl Johnston, Ernesto Amato, Lucrezia Auditore (+5 others)
2019 EJNMMI Research  
MicroPET-based dosimetry of 152Tb is feasible, and the comparison with organ harvesting resulted in acceptable dose discrepancies for body districts that can be segmented on CT.  ...  segmented on CT.  ...  Acknowledgements Preliminary results of this paper were reported as an oral presentation at the 30th Annual Congress of the European Association of Nuclear Medicine (EANM 2017) and published in an abstract  ... 
doi:10.1186/s13550-019-0524-7 pmid:31187358 pmcid:PMC6560118 fatcat:pakjiyxxgvfjzerm5wwq5dhsqa

AAPM Spring Clinical Meeting - Abstract

2021 Journal of Applied Clinical Medical Physics  
However, the conformal dose provided by SRS can prove helpful in avoiding the several organs at risk near the pituitary.  ...  Conclusion: On average, PCIs and HIs are comparable between VMAT and HA plans. CI and GI improvements indicate potential superior sparing of organs at risk.  ...  Results: Comparable target and organ-at-risk (OAR) DVH metrics were observed in the HIPO and robust plans at baseline.  ... 
doi:10.1002/acm2.13289 pmid:34002941 fatcat:6oivewssf5gwnnztmhff4nldle

Radiation dosimetry of 18F-AzaFol: A first in-human use of a folate receptor PET tracer

Silvano Gnesin, Joachim Müller, Irene A. Burger, Alexander Meisel, Marco Siano, Martin Früh, Matthias Choschzick, Cristina Müller, Roger Schibli, Simon M. Ametamey, Philipp A. Kaufmann, Valerie Treyer (+2 others)
2020 EJNMMI Research  
E in-human exceeded the value of 14.0 μSv/MBq extrapolated from pre-clinical data.  ...  TOF-PET images were acquired at 3, 11, 18, 30, 40, 50, and 60 min after the intravenous injection of 327 MBq (range 299-399 MBq) of 18F-AzaFol to establish dosimetry.  ...  Annette Krämer for the GMP synthesis of the 18 Availability of data and materials The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable  ... 
doi:10.1186/s13550-020-00624-2 pmid:32270313 fatcat:cdf4jeijpbfphocamnbnbk2e6u
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