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https://www.readbyqxmd.com/read/27931840/quality-indicators-in-the-intensity-modulated-image-guided-radiotherapy-era
#1
REVIEW
P Gabriele, A Maggio, E Garibaldi, C Bracco, E Delmastro, D Gabriele, A Rosi, F Munoz, N Di Muzio, R Corvò, M Stasi
PURPOSE: To propose new Quality Indicators (QIs) for the Intensity Modulated(IMRT)/Image-Guided(IGRT) Radiotherapy techniques. MATERIALS AND METHODS: Two structure, 10 process and 2 outcome QIs were elaborated. A working group including Radiation Oncologist, Medical Physicist and Radiation Technologists was made up. A preliminary set of indicators was selected on the basis of evidenced critical issues; the criteria to identify more relevant and specific QIs for IMRT/IGRT were defined; structure, process and outcome QIs were defined...
December 2016: Critical Reviews in Oncology/hematology
https://www.readbyqxmd.com/read/27929673/effect-of-gadoxetate-disodium-on-arterial-phase-respiratory-waveforms-using-a-quantitative-fast-fourier-transformation-based-analysis
#2
Matthew S Davenport, Dariya I Malyarenko, Yuxi Pang, Hero K Hussain, Thomas L Chenevert
OBJECTIVE: The purpose of this study is to investigate the effect of gadoxetate disodium administration on arterial phase respiratory waveforms. SUBJECTS AND METHODS: From 2013 to 2015, 107 subjects undergoing liver MRI with either gadoxetate disodium (10 mL diluted 1:1 with saline; injection rate, 2 mL/s; n = 40) or gadobenate dimeglumine (0.2 mL/kg; maximum, 20 mL; injection rate, 2 mL/s; n = 67) were enrolled. Respiratory waveforms obtained during unenhanced and dynamic contrast-enhanced phases were filtered by a physicist, who was blinded to contrast agent and imaging phase, to eliminate electronic and cardiac noise using fast Fourier transformation...
December 8, 2016: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/27929512/a-survey-on-table-tolerances-and-couch-overrides-in-radiotherapy
#3
Bonnie Chinsky, Rakesh Patel, Joshua Panfil, Murat Surucu, John C Roeske
The purpose of this study was to survey current departmental policies on treatment couch overrides and the values of table tolerances used clinically. A 25-question electronic survey on couch overrides and tolerances was sent to full members of the American Association of Physicists in Medicine (AAPM). The first part of the survey asked participants if table overrides were allowed at their institution, who was allowed to perform these overrides, and if imaging was required with overrides. The second part of the survey asked individuals to provide table tolerance data for the following treatment sites: brain/head and neck (H&N), lung, breast, abdo-men/pelvis and prostate...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27929492/treatment-planning-for-metals-using-an-extended-ct-number-scale
#4
John P Mullins, Michael P Grams, Michael G Herman, Debra H Brinkmann, John A Antolak
Metal implants which saturate the CT number scale may require dosimetrist and physicist involvement to manually contour and assign an appropriate value to the metal for accurate dose calculation. This study investigated dose calculation based directly on extended CT scale images for different metals and geometries. The aim was to evaluate extended CT accuracy as a suitable alternative to standard CT methods in the presence of high-Z materials and artifacts, despite the reduced HU resolution of extended CT. Gafchromic film measurements were made for comparison to calculated doses...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27929477/production-review-and-impact-of-technical-quality-control-guidelines-in-a-national-context
#5
Michelle K Nielsen, Kyle E Malkoske, Erika Brown, Kevin Diamond, Normand Frenière, John Grant, Natalie Pomerleau-Dalcourt, Jason Schella, L John Schreiner, Laurent Tantôt, J Eduardo Villareal-Barajas, Jean-Pierre Bissonnette
A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics com-munity during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i...
November 8, 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/27923551/absorbed-dose-and-image-quality-of-varian-truebeam-cbct-compared-with-obi-cbct
#6
Daisuke Kawahara, Shuichi Ozawa, Takeo Nakashima, Tatsuhiko Suzuki, Masato Tsuneda, Sodai Tanaka, Yoshimi Ohno, Yuji Murakami, Yasushi Nagata
PURPOSE: Nowadays, patient positioning and target localization can be verified by using kilovolt cone beam computed tomography (kV-CBCT). There have been various studies on the absorbed doses and image qualities of different kV-CBCT systems. However, the Varian TrueBeam CBCT (TB CBCT) system has not been investigated so far. We assess the image quality and absorbed dose of TB CBCT through comparison with those of on-board imager (OBI) CBCT. METHODS: The image quality was evaluated using two phantoms...
December 3, 2016: Physica Medica: PM
https://www.readbyqxmd.com/read/27919654/american-brachytherapy-society-brachytherapy-treatment-recommendations-for-locally-advanced-cervix-cancer-for-low-income-and%C3%A2-middle-income-countries
#7
Gita Suneja, Derek Brown, Amy Chang, Beth Erickson, Elena Fidarova, Surbhi Grover, Umesh Mahantshetty, Subir Nag, Kailash Narayan, Memory Bvochora-Nsingo, Celia Viegas, Akila N Viswanathan, Ming Yin Lin, David Gaffney
PURPOSE: Most cervix cancer cases occur in low-income and middle-income countries (LMIC), and outcomes are suboptimal, even for early stage disease. Brachytherapy plays a central role in the treatment paradigm, improving both local control and overall survival. The American Brachytherapy Society (ABS) aims to provide guidelines for brachytherapy delivery in resource-limited settings. METHODS AND MATERIALS: A panel of clinicians and physicists with expertise in brachytherapy administration in LMIC was convened...
December 2, 2016: Brachytherapy
https://www.readbyqxmd.com/read/27914679/postgraduate-education-in-radiation-oncology-in-low-and-middle-income-countries
#8
J G Eriksen
Radiation therapy is one of the most cost-effective ways to treat cancer patients on both a curative and palliative basis in low- and middle-income countries (LMICs). Despite this, the gap in radiation oncology capacity is enormous and is even increasing due to a rapid rise in the incidence of cancer cases in LMICs. The urgent need for radiotherapy resources in terms of bunkers and megavoltage machines is important, but equally important is the tremendous lack of properly educated health care professionals...
November 30, 2016: Clinical Oncology: a Journal of the Royal College of Radiologists
https://www.readbyqxmd.com/read/27914589/-big-data-and-their-perspectives-in-radiation-therapy
#9
REVIEW
Sébastien Guihard, Juliette Thariat, Jean-Baptiste Clavier
The concept of big data indicates a change of scale in the use of data and data aggregation into large databases through improved computer technology. One of the current challenges in the creation of big data in the context of radiation therapy is the transformation of routine care items into dark data, i.e. data not yet collected, and the fusion of databases collecting different types of information (dose-volume histograms and toxicity data for example). Processes and infrastructures devoted to big data collection should not impact negatively on the doctor-patient relationship, the general process of care or the quality of the data collected...
November 30, 2016: Bulletin du Cancer
https://www.readbyqxmd.com/read/27908023/introduction-collective-dynamics-of-mechanical-oscillators-and-beyond
#10
Igor V Belykh, Maurizio Porfiri
This focus issue presents a collection of research papers from a broad spectrum of topics related to the modeling, analysis, and control of mechanical oscillators and beyond. Examples covered in this focus issue range from bridges and mechanical pendula to self-organizing networks of dynamic agents, with application to robotics and animal grouping. This focus issue brings together applied mathematicians, physicists, and engineers to address open questions on various theoretical and experimental aspects of collective dynamics phenomena and their control...
November 2016: Chaos
https://www.readbyqxmd.com/read/27904875/history-and-perspectives-of-nuclear-medicine-in-bangladesh
#11
Raihan Hussain
Bangladesh is one of the smaller states in Asia. But it has a long and rich history of nuclear medicine for over sixty years. The progress in science and technology is always challenging in a developing country. In 1958, work for the first Nuclear Medicine facility was commenced in Dhaka in a tin-shed known as 'Radioisotope Centre' and was officially inaugurated in 1962. Since the late 50s of the last century nuclear medicine in Bangladesh has significantly progressed through the years in its course of development, but still the facilities are inadequate...
2016: Asia Oceania Journal of Nuclear Medicine & Biology
https://www.readbyqxmd.com/read/27900621/an-assessment-of-radiation-oncology-medical-physicists-perspectives-on-undertaking-research
#12
Martin A Ebert, Georgia K B Halkett, Melissa Berg, David Cutt, Michael Davis, Desley Hegney, Michael House, Michele Krawiec, Rachel Kearvell, Leanne Lester, Sharon Maresse, Peter McLoone, Jan McKay
As part of a study of the radiation oncology workforce, radiation oncology medical physicists (ROMPs) who had worked in Australia were surveyed regarding their attitudes to participating in research. Responses from 88 ROMPs were available for analysis, representing a broad mix of employment situations and research experience. Greater than 70% of ROMPs described their involvement in research as "liking it" or "loving it", with associated identified benefits including skills development, job satisfaction and career progression...
November 29, 2016: Australasian Physical & Engineering Sciences in Medicine
https://www.readbyqxmd.com/read/27884402/process-and-impact-of-niels-bohr-s-visit-to-japan-and-china-in-1937-a-comparative-perspective
#13
Lei Wang, Jian Yang
At the beginning of the twentieth century, Japan and China, each for its own reasons, invited the famous physicist Niels Bohr to visit and give lectures. Bohr accepted their invitations and made the trip in 1937; however, the topics of his lectures in the two countries differed. In Japan, he mainly discussed quantum mechanics and philosophy, whereas in China, he focused more on atomic physics. This paper begins with a detailed review of Bohr's trip to Japan and China in 1937, followed by a discussion of the impact of each trip from the perspective of the social context...
November 21, 2016: Endeavour
https://www.readbyqxmd.com/read/27867322/a-certified-health-physicist-s-reflections-on-a-40-year-career-in-radiation-protection
#14
Mark L Miller
This is a reflection from a certified health physicist regarding his becoming aware, during his 40-year career, that the linear no-threshold (LNT) model and the associated As Low As Reasonably Achievable concept have no scientific basis and make no positive contribution to radiation safety. They should be replaced by an alternative, scientifically based model that includes a threshold, below which there is no harm, and recognition of hormesis and the adaptive response, which reflect the benefits of low-dose and low-dose-rate radiation exposure...
October 2016: Dose-response: a Publication of International Hormesis Society
https://www.readbyqxmd.com/read/27853728/development-of-radrob15-a-robot-for-detecting-radioactive-contamination-in-nuclear-medicine-departments
#15
A Shafe, S M J Mortazavi, A Joharnia, Gh H Safaeyan
Accidental or intentional release of radioactive materials into the living or working environment may cause radioactive contamination. In nuclear medicine departments, radioactive contamination is usually due to radionuclides which emit high energy gamma photons and particles. These radionuclides have a broad range of energies and penetration capabilities. Rapid detection of radioactive contamination is very important for efficient removing of the contamination without spreading the radionuclides. A quick scan of the contaminated area helps health physicists locate the contaminated area and assess the level of activity...
September 2016: Journal of Biomedical Physics & Engineering
https://www.readbyqxmd.com/read/27842674/radiation-dose-in-cardiac-spect-ct-an-estimation-of-ssde-and-effective-dose
#16
Hamid Abdollahi, Isaac Shiri, Yazdan Salimi, Maghsoud Sarebani, Reza Mehdinia, Mohammad Reza Deevband, Seied Rabi Mahdavi, Ahmad Sohrabi, Ahmad Bitarafan-Rajabi
AIMS: The dose levels for Computed Tomography (CT) localization and attenuation correction of Single Photon Emission Computed Tomography (SPECT) are limited and reported as Volume Computed Tomography Dose Index (CTDIvol) and Dose-Length Product (DLP). This work presents CT dose estimation from Cardiac SPECT/CT based on new American Association of Physicists in Medicine (AAPM) Size Specific Dose Estimation (SSDE) parameter, effective dose, organ doses and also emission dose from nuclear issue...
December 2016: European Journal of Radiology
https://www.readbyqxmd.com/read/27811477/models-of-the-life-force-genus-endemicus-etc-a-physicist-s-comments
#17
Alex Hankey
No abstract text is available yet for this article.
2016: Forschende Komplementärmedizin, Research in Complementary Medicine
https://www.readbyqxmd.com/read/27786546/ct-of-facial-fracture-fixation-an-experimental-study-of-artifact-reducing-methods
#18
Elina M Peltola, Teemu Mäkelä, Ville Haapamäki, Anni Suomalainen, Junnu Leikola, Seppo K Koskinen, Mika Kortesniemi, Mika P Koivikko
OBJECTIVES: This study aimed to determine the optimal postoperative CT imaging method that enables best visualization of facial bony structures in the vicinity of osteosynthesis material. METHODS: Conducted at (blinded 1), this study relied on scanning a phantom with cone-beam computed tomography (CBCT), a 64-slice computed tomography (CT) and a high-definition multi-slice CT with dual-energy scan (providing monochromatic images of 70, 100, 120 and 140 keV energy levels) and iterative reconstruction (IR) methods...
October 27, 2016: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/27782723/automatic-multiorgan-segmentation-in-ct-images-of-the-male-pelvis-using-region-specific-hierarchical-appearance-cluster-models
#19
Dengwang Li, Pengxiao Zang, Xiangfei Chai, Yi Cui, Ruijiang Li, Lei Xing
PURPOSE: Accurate segmentation of pelvic organs in CT images is of great importance in external beam radiotherapy for prostate cancer. The aim of this studying is to develop a novel method for automatic, multiorgan segmentation of the male pelvis. METHODS: The authors' segmentation method consists of several stages. First, a pretreatment includes parameterization, principal component analysis (PCA), and an established process of region-specific hierarchical appearance cluster (RSHAC) model which was executed on the training dataset...
October 2016: Medical Physics
https://www.readbyqxmd.com/read/27782700/re-examining-tg-142-recommendations-in-light-of-modern-techniques-for-linear-accelerator-based-radiosurgery
#20
Austin M Faught, Michael Trager, Fang-Fang Yin, John Kirkpatrick, Justus Adamson
PURPOSE: The recent development of multifocal stereotactic radiosurgery (SRS) using a single isocenter volumetric modulated arc theory (VMAT) technique warrants a re-examination of the quality assurance (QA) tolerances for routine mechanical QA recommended by the American Association of Physicists in Medicine Task Group Report Number 142. Multifocal SRS can result in targets with small volumes being at a large off-axis distance from the treatment isocenter. Consequently, angular errors in the collimator, patient support assembly (PSA), or gantry could have an increased impact on target coverage...
October 2016: Medical Physics
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