308 results on '"Tsapaki V"'
Search Results
102. Radiation dose measurements to the interventional cardiologist using an electronic personal dosemeter
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Tsapaki, V., primary
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- 2004
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103. Comparison of a conventional and a flat-panel digital system in interventional cardiology procedures
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Tsapaki, V, primary, Kottou, S, additional, Kollaros, N, additional, Dafnomili, P, additional, Koutelou, M, additional, Vano, E, additional, and Neofotistou, V, additional
- Published
- 2004
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104. Quality control of a laser camera with the SMPTE test pattern: optical density variations with printing format and frame position
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Tsalafoutas, I A, primary, Tsapaki, V, additional, Koulentianos, E, additional, and Triantopoulou, C, additional
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- 2004
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105. Patient dose values in a dedicated Greek cardiac centre
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Tsapaki, V, primary, Kottou, S, additional, Vano, E, additional, Faulkner, K, additional, Giannouleas, J, additional, Padovani, R, additional, Kyrozi, E, additional, Koutelou, M, additional, Vardalaki, E, additional, and Neofotistou, V, additional
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- 2003
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106. 603 Assessment of adrenergic activity using MIBG in patients with LBBB
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KOUTELOU, M, primary, THEODORAKOS, A, additional, TSAPAKI, V, additional, ATHANASOPOULOS, G, additional, EXARHOU, A, additional, and COKKINOS, D, additional
- Published
- 2003
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107. Quality criteria for cardiac images in diagnostic and interventional cardiology
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Bernardi, G, primary, Padovani, R, additional, Morocutti, G, additional, Spedicato, L, additional, Giannuleas, J D, additional, Neofotistou, E, additional, Manginas, A, additional, Goicolea, J C, additional, McNeill, J, additional, Vaño, E, additional, Marzocchi, A, additional, Tsapaki, V, additional, Fioretti, P M, additional, and Malone, J, additional
- Published
- 2001
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108. Application of European Commission reference dose levels in CT examinations in Crete, Greece
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Tsapaki, V, primary, Kottou, S, additional, and Papadimitriou, D, additional
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- 2001
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109. Patient and Staff Dosimetry Problems in Interventional Radiology
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Tsapaki, V., primary
- Published
- 2001
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110. Personnel Doses in Haemodynamic Units in Greece
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Kottou, S., primary, Neofotistou, V., additional, Tsapaki, V., additional, Lobotessi, H., additional, Manetou, A., additional, and Molfetas, M.G., additional
- Published
- 2001
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111. Effective Dose to a Patient Undergoing Coronary Angiography
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Lobotessi, H., primary, Karoussou, A., additional, Neofotistou, V., additional, Louisu, A., additional, and Tsapaki, V., additional
- Published
- 2001
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112. What are the clinical and technical factors that influence the kerma-area product in percutaneous coronary intervention?
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Tsapaki, V., Maniatis, P. N., Magginas, A., Voudris, V., Patsilinakos, S., Vranzta, T., Vano, E., and Cokkinos, D. S.
- Subjects
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CARDIOLOGY , *MEDICAL radiology , *MEDICAL equipment , *THERAPEUTICS , *HEART diseases , *FLUOROSCOPY - Abstract
The purpose of the paper is to define predictors of the kerma-area product (KAP) in percutaneous coronary intervention (PCI). Two new digital X-ray interventional cardiology systems recently installed were included. A total of 398 PCI procedures were carried out by 6 board-certified senior interventional cardiologists with more than 15 years' experience and good knowledge of radiation protection measures. Clinical, radiation and procedural data were collected based on a detailed protocol developed by the SENTINEL cardiology subgroup. Correlation with clinical and procedure factors was then investigated. A significant correlation was found between fluoroscopy time and (i) lesion classification, (ii) the level of tortuosity and (iii) the number of vessels treated. No statistically significant differences were observed in the complexity of the case between operators. However, large differences were found in the KAP among operators, which were mostly attributed to the different number of frames taken by each operator. There was no statistically significant correlation between complexity and the total number of frames. The study showed that, in certain circumstances, the clinical need to successfully perform PCI takes precedence over radiation safety concerns. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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113. EXPERIMENTAL EVALUATION OF PCXMC AND PREPARE CODES USED IN CONVENTIONAL RADIOLOGY.
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KheIassi-Toutaouil, N., Berkani, Y., Tsapaki, V., Toutaoui, A. E. K., Merad, A., Frahi-Arnroun, A., and Brahimi, Z.
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THERMOLUMINESCENCE dosimetry ,DRUG dosage ,ORGANS (Anatomy) ,ELECTRONIC data processing ,MEDICAL digital radiography ,RADIOLOGY - Abstract
The objective of this study is to evaluate the precision of dose-calculation computer codes used in our laboratory (PCXMC and PREPARE) for organ dose evaluation. Measurements of entrance and organ dose were performed using ionisation chamber and thermoluminescence dosimetry. To obtain a mean dose of organ, we have used the Rando-Alderson phantom. The results showed that computed and measured doses correlate well (within 28%) in 60% of the samples. The percentage shows that the computed doses correlate with the experimental doses rather well for PCXMC software than PREPARE. Although the two programs are based on the Monte-Carlo method, their calculations differ. PCXMC carries out a simulation of the trajectory of the photon, whereas PREPARE provides interpolated values. Our experimental results are close to the values given by the PCXMC, a program which takes into account the weight, the height of the patient and field dimensions. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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114. 603 Assessment of adrenergic activity using MIBG in patients with LBBB
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Koutelou, M., Theodorakos, A., Tsapaki, V., Athanasopoulos, G., Exarhou, A., and Cokkinos, D.V.
- Subjects
SYMPATHOMIMETIC agents - Abstract
An abstract of the study "Assessment of Adrenergic Activity Using MIBG in Patients With LBBB," by M. Koutelou and colleagues is presented.
- Published
- 2004
115. Leadership and mentoring in medical physics: The experience of a medical physics international mentoring program
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J.C. Santos, A.H. Ng, L. Giansante, L.F. Goulart, Eva Bezak, Virginia Tsapaki, Y.H. Lin, Kwan Hoong Ng, A.C.A. Sirico, Santos, JC, Goulart, LF, Giansante, L, Lin, YH, Sirico, ACA, Ng, AH, Tsapaki, V, Bezak, E, and Ng, KH
- Subjects
leadership ,medicine.medical_specialty ,Biophysics ,General Physics and Astronomy ,Computer-assisted web interviewing ,medical physics ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,career ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Medical physics ,Group program ,Set (psychology) ,SWOT analysis ,ComputingMilieux_THECOMPUTINGPROFESSION ,business.industry ,Physics ,Mentors ,Professional development ,mentoring program ,Mentoring ,General Medicine ,TUTORIA ,Personal development ,ComputingMilieux_GENERAL ,Leadership ,Work (electrical) ,030220 oncology & carcinogenesis ,Psychology ,business ,Program Evaluation ,Career development - Abstract
Mentoring aims to improve careers and create benefits for the participants' personal and professional lives. Mentoring can be an individual or a shared experience for a group, while the mentor’s role remains the same in both models. Mentors should increase confidence, teach, inspire, and set examples, helping the mentees to mould their path, contributing to the pursuit of their personal and professional goals. This study aims to report on the experience of early-career medical physics professionals and postgraduate students participating in a global mentoring program and to assess the impact of this activity on their professional development. The objectives of this mentoring program are to develop leadership roles among young medical physicists and to provide guidance and support. An online questionnaire was administered to the mentee participants. The analysis of their responses is reported in this work and the current status of the programme was examined using a SWOT analysis.In general, the mentoring experience had a positive impact on the mentees. The mentors were found especially helpful in the decision-making situations and in other conflicts that may arise with career development.Additionally, the mentees felt that mentoring contributed to the development of leadership skills required for the job market and assist in personal development. This paper concludes that participation of young medical physicists in a mentoring group program is beneficial to their career and therefore should be encouraged. Refereed/Peer-reviewed
- Published
- 2020
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116. The European Federation of Organisations for Medical Physics (EFOMP) White Paper: Big data and deep learning in medical imaging and in relation to medical physics profession
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Annalisa Trianni, Virginia Tsapaki, John Damilakis, Marco Brambilla, Hans-Erik Källman, Mika Kortesniemi, Ad J.J. Maas, Paolo Russo, Kortesniemi, M., Tsapaki, V., Trianni, A., Russo, P., Maas, A., Kallman, H. -E., Brambilla, M., and Damilakis, J.
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Big Data ,Diagnostic Imaging ,medicine.medical_specialty ,Computer science ,Health Personnel ,Big data ,Biophysics ,General Physics and Astronomy ,Data validation ,Health Physic ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,White paper ,Deep Learning ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Medical physics ,Competence (human resources) ,Societies, Medical ,Data collection ,business.industry ,Professional development ,General Medicine ,3. Good health ,Europe ,030220 oncology & carcinogenesis ,Data quality ,Data analysis ,business ,Health Physics ,Human - Abstract
Big data and deep learning will profoundly change various areas of professions and research in the future. This will also happen in medicine and medical imaging in particular. As medical physicists, we should pursue beyond the concept of technical quality to extend our methodology and competence towards measuring and optimising the diagnostic value in terms of how it is connected to care outcome. Functional implementation of such methodology requires data processing utilities starting from data collection and management and culminating in the data analysis methods. Data quality control and validation are prerequisites for the deep learning application in order to provide reliable further analysis, classification, interpretation, probabilistic and predictive modelling from the vast heterogeneous big data. Challenges in practical data analytics relate to both horizontal and longitudinal analysis aspects. Quantitative aspects of data validation, quality control, physically meaningful measures, parameter connections and system modelling for the future artificial intelligence (AI) methods are positioned firmly in the field of Medical Physics profession. It is our interest to ensure that our professional education, continuous training and competence will follow this significant global development.
- Published
- 2018
117. Design and Use of a Custom Phantom for Regular Tests of Radiography Apparatus: A Feasibility Study.
- Author
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Dukov N, Valkova VM, Yordanova M, Tsapaki V, and Bliznakova K
- Abstract
This study investigates the feasibility of employing an in-house-developed physical phantom dedicated to the weekly quality control testing of radiographic systems, performed by radiographers. For this purpose, a 3D phantom was fabricated, featuring test objects, including a model representing a lesion. Alongside this phantom, a commercial phantom, specifically, IBA's Primus L, was utilized. Weekly imaging of both phantoms was conducted over a span of four weeks, involving different imaging protocols and anode voltages. Subsequently, the obtained data underwent visual evaluation, as well as measurement of the intensity of selected regions of interest. The average values for three incident kilovoltages remained consistently stable over the four weeks, with the exception of the "low energy" case, which exhibited variability during the first week of measurements. Following experiments in "Week 1", the X-Ray unit was identified as malfunctioning and underwent necessary repairs. The in-house-developed phantom demonstrated its utility in assessing the performance of the X-Ray system.
- Published
- 2024
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118. Strengthening education and training programmes for medical physics in Asia and the Pacific: the IAEA non-agreement technical cooperation (TC) regional RAS6088 project.
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Jamal N, Krisanachinda A, Tsapaki V, Islam MR, Pawiro S, Al Omari M, Yeong CH, Myint TT, Kakakhel MB, Kharita MH, Lee CLJ, Ismail A, Nguyen TB, Knoll P, Ciraj-Bjelac O, and Malek M
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- Radiopharmaceuticals chemistry, Radiopharmaceuticals therapeutic use, Asia, International Cooperation, Radiology education, Nuclear Medicine education, Education, Continuing, Health Physics education, International Agencies
- Abstract
This article documents the work conducted in implementing the IAEA non-agreement TC regional RAS6088 project "Strengthening Education and Training Programmes for Medical Physics". Necessary information on the project was collected from the project counterparts via emails for a period of one month, starting from 21st September 2023, and verified at the Final Regional Coordination Meeting in Bangkok, Thailand from 30th October 2023 to 3rd November 2023. Sixty-three participants were trained in 5 Regional Training Courses (RTCs), with 48%, 32% and 20% in radiation therapy, diagnostic radiology, and nuclear medicine, respectively. One RTC was successfully organised to introduce molecular biology as an academic module to participants. Three participating Member States, namely United Arab Emirates (UAE), Nepal and Afghanistan have initiated processes to start the postgraduate master medical physics education programmes by coursework, adopting the IAEA TCS56 Guidelines. UAE has succeeded in completing the process while Nepal and Afghanistan have yet to initiate the programme. The postgraduate master medical physics programmes by coursework were strengthened in Indonesia, Jordan, Malaysia, Pakistan, Syria, and Thailand, along with the national registration of medical physicists. In particular, Thailand has revised 6 postgraduate master medical physics programmes by coursework during the tenure of this project. Home Based Assignment and RTCs have resulted in two publications. In conclusion, the RAS6088 project was found to have achieved its planned outcomes despite challenges faced due to the COVID-19 pandemic. It is proposed that a follow up project be implemented to increase the number of Member States who are better prepared to improve medical physics education and training in the region., (© 2024. Australasian College of Physical Scientists and Engineers in Medicine.)
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- 2024
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119. Two-Dimensional Mammography Imaging Techniques for Screening Women with Silicone Breast Implants: A Pilot Phantom Study.
- Author
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Fitton I, Tsapaki V, Zerbib J, Decoux A, Kumar A, Stembert A, Malchair F, Van Ngoc Ty C, and Fournier L
- Abstract
This study aimed to evaluate the impact of three two-dimensional (2D) mammographic acquisition techniques on image quality and radiation dose in the presence of silicone breast implants (BIs). Then, we propose and validate a new International Atomic Energy Agency (IAEA) phantom to reproduce these techniques. Images were acquired on a single Hologic Selenia Dimensions
® unit. The mammography of the left breast of a single clinical case was included. Three methods of image acquisition were identified. They were based on misused, recommended, and reference settings. In the clinical case, image criteria scoring and the signal-to-noise ratio on breast tissue (SNRBT ) were determined for two 2D projections and compared between the three techniques. The phantom study first compared the reference and misused settings by varying the AEC sensor position and, second, the recommended settings with a reduced current-time product (mAs) setting that was 13% lower. The signal-difference-to-noise ratio ( SDNR ) and detectability indexes at 0.1 mm (d' 0.1 mm) and 0.25 mm (d' 0.25 mm) were automatically quantified using ATIA software. Average glandular dose (AGD) values were collected for each acquisition. A statistical analysis was performed using Kruskal-Wallis and corrected Dunn tests ( p < 0.05). The SNRBT was 2.6 times lower and the AGD was -18% lower with the reference settings compared to the recommended settings. The SNRBT values increased by +98% with the misused compared to the recommended settings. The AGD increased by +79% with the misused settings versus the recommended settings. The median values of the reference settings were 5.8 (IQR 5.7-5.9), 1.2 (IQR 0.0), 7.0 (IQR 6.8-7.2) and 1.2 (IQR 0.0) mGy and were significantly lower than those of the misused settings ( p < 0.03): 7.9 (IQR 6.1-9.7), 1.6 (IQR 1.3-1.9), 9.2 (IQR 7.5-10.9) and 2.2 (IQR 1.4-3.0) mGy for the SDNR , d' 0.1 mm, d' 0.25 mm and the AGD, respectively. A comparison of the recommended and reduced settings showed a reduction of -6.1 ± 0.6% ( p = 0.83), -7.7 ± 0.0% ( p = 0.18), -6.4 ± 0.6% ( p = 0.19) and -13.3 ± 1.1% ( p = 0.53) for the SDNR , d' 0.1 mm, d' 0.25 mm and the AGD, respectively. This study showed that the IAEA phantom could be used to reproduce the three techniques for acquiring 2D mammography images in the presence of breast implants for raising awareness and for educational purposes. It could also be used to evaluate and optimize the manufacturer's recommended settings.- Published
- 2024
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120. Automated Quality Control Solution for Radiographic Imaging of Lung Diseases.
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Kleefeld C, Castillo Lopez JP, Costa PR, Fitton I, Mohamed A, Pesznyak C, Ruggeri R, Tsalafoutas I, Tsougos I, Wong JHD, Zdesar U, Ciraj-Bjelac O, and Tsapaki V
- Abstract
Background/Objectives : Radiography is an essential and low-cost diagnostic method in pulmonary medicine that is used for the early detection and monitoring of lung diseases. An adequate and consistent image quality (IQ) is crucial to ensure accurate diagnosis and effective patient management. This pilot study evaluates the feasibility and effectiveness of the International Atomic Energy Agency (IAEA)'s remote and automated quality control (QC) methodology, which has been tested in multiple imaging centers. Methods : The data, collected between April and December 2022, included 47 longitudinal data sets from 22 digital radiographic units. Participants submitted metadata on the radiography setup, exposure parameters, and imaging modes. The database comprised 968 exposures, each representing multiple image quality parameters and metadata of image acquisition parameters. Python scripts were developed to collate, analyze, and visualize image quality data. Results : The pilot survey identified several critical issues affecting the future implementation of the IAEA method, as follows: (1) difficulty in accessing raw images due to manufacturer restrictions, (2) variability in IQ parameters even among identical X-ray systems and image acquisitions, (3) inconsistencies in phantom construction affecting IQ values, (4) vendor-dependent DICOM tag reporting, and (5) large variability in SNR values compared to other IQ metrics, making SNR less reliable for image quality assessment. Conclusions : Cross-comparisons among radiography systems must be taken with cautious because of the dependence on phantom construction and acquisition mode variations. Awareness of these factors will generate reliable and standardized quality control programs, which are crucial for accurate and fair evaluations, especially in high-frequency chest imaging.
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- 2024
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121. The use of Dose Management Systems in Europe: Results of an ESR EuroSafe Imaging Questionnaire.
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Loose R, Vaño E, Ammon J, Andersson J, Brat H, Brkljacic B, Caikovska K, Corridori R, Damilakis J, De Bondt T, Frija G, Granata C, Hoeschen C, Kotter E, Kralik I, McNulty J, Paulo G, and Tsapaki V
- Abstract
Dose management systems (DMS) are an essential tool for quality assurance and optimising patient radiation exposure. For radiologists and medical physicists, they are important for managing many radiation protection tasks. In addition, they help fulfil the requirements of Directive 2013/59/EURATOM regarding the electronic transmission of dosimetric data and the detection of unintended patient exposures. The EuroSafe Imaging Clinical Dosimetry and Dose Management Working Group launched a questionnaire on the use of DMS in European member states and analysed the results in terms of modalities, frequency of radiological procedures, involvement of medical physics experts (MPEs), legal requirements, and local issues (support by information technology (IT), modality interfaces, protocol mapping, clinical workflow, and associated costs). CRITICAL RELEVANCE STATEMENT: Despite the great advantages of dose management systems for optimising radiation protection, distribution remains insufficient. This questionnaire shows that reasons include: a lack of DICOM interfaces, insufficient harmonisation of procedure names, lack of medical physicist and IT support, and costs. KEY POINTS: Quantitative radiation dose information is essential for justification and optimisation in medical imaging. Guidelines are required to ensure radiation dose management systems quality and for acceptance testing. Verifying dose data management is crucial before dose management systems clinical implementation. Medical physics experts are professionals who have important responsibilities for the proper management of dose monitoring., (© 2024. The Author(s).)
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- 2024
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122. Clinical diagnostic reference levels in neuroradiology based on clinical indication.
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Aly A, Tsapaki V, Ahmed AZ, Own A, Patro S, Al Naemi H, and Kharita MH
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- Humans, Adult, Male, Middle Aged, Female, Aged, Radiation Exposure analysis, Intracranial Arteriovenous Malformations radiotherapy, Intracranial Arteriovenous Malformations diagnostic imaging, Stroke diagnostic imaging, Intracranial Aneurysm diagnostic imaging, Diagnostic Reference Levels, Neuroradiography methods, Aged, 80 and over, Young Adult, Radiation Dosage
- Abstract
This study focuses on patient radiation exposure in interventional neuroradiology (INR) procedures, a field that has advanced significantly since its inception in the 1980s. INR employs minimally invasive techniques to treat complex cerebrovascular diseases in the head, neck, and spine. The study establishes diagnostic reference levels (DRLs) for three clinical indications (CIs): stroke (S), brain aneurysms (ANs), and brain arteriovenous malformation (AVM). Data from 209 adult patients were analyzed, and DRLs were determined in terms of various dosimetric and technical quantities. For stroke, the established DRLs median values were found to be 78 Gy cm2, 378 mGy, 118 mGy, 12 min, 442 images, and 15 runs. Similarly, DRLs for brain AN are 85 Gy cm2, 611 mGy, 95.5 mGy, 19.5, 717 images, and 26 runs. For brain AVM, the DRL's are 180 Gy cm2, 1144 mGy, 537 mGy, 36 min, 1375 images, and 31 runs. Notably, this study is unique in reporting DRLs for specific CIs within INR procedures, providing valuable insights for optimizing patient safety and radiation exposure management., (© The Author(s) 2024. Published by Oxford University Press.)
- Published
- 2024
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123. Estimating brain and eye lens dose for the cardiologist in interventional cardiology-are the dose levels of concern?
- Author
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Hulthén M, Tsapaki V, and Karambatsakidou A
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- Humans, Thermoluminescent Dosimetry, Cardiology, Radiography, Interventional methods, Lens, Crystalline radiation effects, Radiation Dosage, Phantoms, Imaging, Cardiologists, Brain radiation effects, Brain diagnostic imaging, Occupational Exposure analysis, Occupational Exposure prevention & control
- Abstract
Objectives: To establish conversion coefficients (CCs), between mean absorbed dose to the brain and eye lens of the cardiologist and the air kerma-area product, PKA, for a set of projections in cardiac interventional procedures. Furthermore, by taking clinical data into account, a method to estimate the doses per procedure, or annual dose, is presented., Methods: Thermoluminescence dosimeters were used together with anthropomorphic phantoms, simulating a cardiologist performing an interventional cardiac procedure, to estimate the CCs for the brain and eye lens dose for nine standard projections, and change in patient size and x-ray spectrum. Additionally, a single CC has been estimated, accounting for each projections fraction of use in the clinic and associated PKA using clinical data from the dose monitoring system in our hospital., Results: The maximum CCs for the eye lens and segment of the brain, is 5.47 μGy/Gycm2 (left eye lens) and 1.71 μGy/Gycm2 (left brain segment). The corresponding weighted CCs: are 3.39 μGy/Gycm2 and 0.89 μGy/Gycm2, respectively., Conclusions: Conversion coefficients have been established under actual scatter conditions, showing higher doses on the left side of the operator. Using modern interventional x-ray equipment, interventional cardiac procedures will not cause high radiation dose levels to the operator when a ceiling mounted shield is used, otherwise there is a risk that the threshold dose values for cataract will be reached., Advance in Knowledge: In addition to the CCs for the different projections, methods for deriving a single CC per cardiac interventional procedure and dose per year were introduced., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology.)
- Published
- 2024
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124. Automatic image quality evaluation in digital radiography using for-processing and for-presentation images.
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Tsalafoutas IA, AlKhazzam S, Tsapaki V, and Kharita MH
- Subjects
- Humans, Radiation Dosage, Radiography, X-Rays, Phantoms, Imaging, Radiographic Image Enhancement, Software
- Abstract
Purpose: To investigate the impact of digital image post-processing algorithms on various image quality (IQ) metrics of radiographic images under different exposure conditions., Methods: A custom-made phantom constructed according to the instructions given in the IAEA Human Health Series No.39 publication was used, along with the respective software that automatically calculates various IQ metrics. Images with various exposure parameters were acquired with a digital radiography unit, which for each acquisition produces two images: one for-processing (raw) and one for-presentation (clinical). Various examination protocols were used, which incorporate diverse post-processing algorithms. The IQ metrics' values (IQ-scores) obtained were analyzed to investigate the effects of increasing incident air kerma (IAK) on the image receptor, tube potential (kVp), additional filtration, and examination protocol on image quality, and the differences between image type (raw or clinical)., Results: The IQ-scores were consistent for repeated identical exposures for both raw and clinical images. The effect that changes in exposure parameters and examination protocol had on IQ-scores were different depending on the IQ metric and image type. The expected positive effect that increasing IAK and decreasing tube potential should have on IQ was clearly exhibited in two IQ metrics only, the signal difference-to-noise-ratio (SDNR) and the detectability index (d'), for both image types. No effect of additional filtration on any of the IQ metrics was detected on images of either type. An interesting finding of the study was that for all different image acquisition selections the d' scores were larger in raw images, whereas the other IQ metrics were larger in clinical images for most of the cases., Conclusions: Since IQ-scores of raw and their respective clinical images may be largely different, the same type of image should be consistently used for monitoring IQ constancy and when results from different X-ray systems are compared., (© 2024 The Authors. Journal of Applied Clinical Medical Physics is published by Wiley Periodicals, Inc. on behalf of The American Association of Physicists in Medicine.)
- Published
- 2024
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125. Quality Assurance Considerations in Radiopharmaceutical Therapy Dosimetry Using PLANETDose: An International Atomic Energy Agency Study.
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Kayal G, Barbosa N, Marín CC, Ferrer L, Fragoso-Negrín JA, Grosev D, Gupta SK, Hidayati NR, Moalosi TCG, Poli GL, Thakral P, Tsapaki V, Vauclin S, Vergara-Gil A, Knoll P, Hobbs RF, and Bardiès M
- Subjects
- Humans, Radiometry methods, Single Photon Emission Computed Tomography Computed Tomography, Liver, Radiopharmaceuticals therapeutic use, Neoplasms
- Abstract
Implementation of radiopharmaceutical therapy dosimetry varies depending on the clinical application, dosimetry protocol, software, and ultimately the operator. Assessing clinical dosimetry accuracy and precision is therefore a challenging task. This work emphasizes some pitfalls encountered during a structured analysis, performed on a single-patient dataset consisting of SPECT/CT images by various participants using a standard protocol and clinically approved commercial software. Methods: The clinical dataset consisted of the dosimetric study of a patient administered with [
177 Lu]Lu-DOTATATE at Tygerberg Hospital, South Africa, as a part of International Atomic Energy Agency-coordinated research project E23005. SPECT/CT images were acquired at 5 time points postinjection. Patient and calibration images were reconstructed on a workstation, and a calibration factor of 122.6 Bq/count was derived independently and provided to the participants. A standard dosimetric protocol was defined, and PLANETDose (version 3.1.1) software was installed at 9 centers to perform the dosimetry of 3 treatment cycles. The protocol included rigid image registration, segmentation (semimanual for organs, activity threshold for tumors), and dose voxel kernel convolution of activity followed by absorbed dose (AD) rate integration to obtain the ADs. Iterations of the protocol were performed by participants individually and within collective training, the results of which were analyzed for dosimetric variability, as well as for quality assurance and error analysis. Intermediary checkpoints were developed to understand possible sources of variation and to differentiate user error from legitimate user variability. Results: Initial dosimetric results for organs (liver and kidneys) and lesions showed considerable interoperator variability. Not only was the generation of intermediate checkpoints such as total counts, volumes, and activity required, but also activity-to-count ratio, activity concentration, and AD rate-to-activity concentration ratio to determine the source of variability. Conclusion: When the same patient dataset was analyzed using the same dosimetry procedure and software, significant disparities were observed in the results despite multiple sessions of training and feedback. Variations due to human error could be minimized or avoided by performing intensive training sessions, establishing intermediate checkpoints, conducting sanity checks, and cross-validating results across physicists or with standardized datasets. This finding promotes the development of quality assurance in clinical dosimetry., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)- Published
- 2024
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126. Technical specifications of dose management systems: An international atomic energy agency survey.
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Tsalafoutas IA, Arlany L, Titovich E, Pynda Y, Ruggeri R, Sánchez RM, Reiser I, and Tsapaki V
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- Humans, Surveys and Questionnaires, Nuclear Energy
- Abstract
Purpose: Dose management systems (DMS) have been introduced in radiological services to facilitate patient radiation dose management and optimization in medical imaging. The purpose of this study was to gather as much information as possible on the technical characteristics of DMS currently available, regarding features that may be considered essential for simply ensuring regulatory compliance or desirable to fully utilize the potential role of DMS in optimization of many aspects of radiological examinations., Methods: A technical survey was carried out and all DMS developers currently available (both commercial and open source) were contacted and were asked to participate. An extensive questionnaire was prepared and uploaded in the IAEA International Research Integration System (IRIS) online platform which was used for data collection process. Most of the questions (93%) required a "Yes/No" answer, to facilitate an objective analysis of the survey results. Some free text questions and comments' slots were also included, to allow participants to give additional information and clarifications where necessary. Depending on the answer, they were considered either as "Yes" or "No.", Results: Given the way that the questions were posed, every positive response indicated that a feature was offered. Thus, the percentage of positive responses was used as a measure of adherence. The percentages of positive answers per section (and sub-section) are presented in graphs and limitations of this type of analysis are discussed in detail., Conclusions: The results of this survey clearly exhibit that large differences exist between the various DMS developers. Consequently, potential end users of a DMS should carefully determine which of the features available are essential for their needs, prioritize desirable features, but also consider their infrastructure, the level of support required and the budget available before selecting a DMS., (© 2023 The Authors. Journal of Applied Clinical Medical Physics is published by Wiley Periodicals, Inc. on behalf of The American Association of Physicists in Medicine.)
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- 2024
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127. How to establish and use local diagnostic reference levels: an ESR EuroSafe Imaging expert statement.
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Damilakis J, Frija G, Brkljacic B, Vano E, Loose R, Paulo G, Brat H, and Tsapaki V
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- 2023
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128. Digital radiography image quality evaluation using various phantoms and software.
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Tsalafoutas IA, AlKhazzam S, Tsapaki V, AlNaemi H, and Kharita MH
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- Humans, Radiation Dosage, Phantoms, Imaging, Radiographic Image Enhancement methods, Software
- Abstract
Purpose: To investigate the effect of the exposure parameters on image quality (IQ) metrics of phantom images, obtained automatically using software or from visual evaluation., Methods: Three commercial phantoms and a homemade phantom constructed according to the instructions given in the IAEA Human Health Series No. 39 publication were used, along with the respective software that estimate automatically various IQ metrics. Images with various exposure parameters were acquired in a digital radiography (DR) unit. For the commercial phantoms, visual evaluations were also performed. The IQ scores obtained were analyzed to investigate the effects of increasing incident air kerma (IAK), tube potential (kVp), additional filtration, and acquisition protocol on IQ., Results: The effects of the exposure parameters on the IQ metrics, determined with the commercial and the IAEA phantoms, were not the same. For example, clear trends of improvement of IQ scores with increased IAK and reduction of most IQ scores with increased kVp were observed mostly with the IAEA phantom, but not with the commercial phantoms (for both automatic and visual scoring methods). For all phantoms, the maximum variations in IQ scores observed for repeated identical exposures were almost always below 10% with automatic evaluation whereas, for visual evaluation, reached 17%., Conclusions: Failure to detect some expected trends with the complex commercial phantoms may be attributed to the fact that IQ in DR is more strongly affected by the post-processing procedures, which may mask the effect of other parameters on IQ, something that was not observed with the simple IAEA phantom., (© 2022 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)
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- 2022
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129. Notifications and alerts in patient dose values for computed tomography and fluoroscopy-guided interventional procedures.
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Vano E, Loose R, Frija G, Paulo G, Efstathopoulos E, Granata C, Corridori R, Torresin A, Andersson JS, Tsapaki V, Ammon J, and Hoeschen C
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- Fluoroscopy methods, Humans, Radiation Dosage, Radiography, Interventional, Radiology, Interventional methods, Tomography, X-Ray Computed methods, Radiation Protection methods
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The terms "notifications" and "alerts" for medical exposures are used by several national and international organisations. Recommendations for CT scanners have been published by the American Association of Physicists in Medicine. Some interventional radiology societies as well as national authorities have also published dose notifications for fluoroscopy-guided interventional procedures. Notifications and alerts may also be useful for optimisation and to avoid unintended and accidental exposures. The main interest in using these values for high-dose procedures (CT and interventional) is to optimise imaging procedures, reducing the probability of stochastic effects and avoiding tissue reactions. Alerts in X-ray systems may be considered before procedures (as in CT), during procedures (in some interventional radiology systems), and after procedures, when the patient radiation dose results are known and processed. This review summarises the different uses of notifications and alerts to help in optimisation for CT and for fluoroscopy-guided interventional procedures as well as in the analysis of unintended and accidental medical exposures. The paper also includes cautions in setting the alert values and discusses the benefits of using patient dose management systems for the alerts, their registry and follow-up, and the differences between notifications, alerts, and trigger levels for individual procedures and the terms used for the collective approach, such as diagnostic reference levels. KEY POINTS: • Notifications and alerts on patient dose values for computed tomography (CT) and fluoroscopy-guided interventional procedures (FGIP) allow to improve radiation safety and contribute to the avoidance of radiation injuries and unintended and accidental exposures. • Alerts may be established before the imaging procedures (as in CT) or during and after the procedures as for FGIP. • Dose management systems should include notifications and alerts and their registry for the hospital quality programmes., (© 2022. The Author(s).)
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- 2022
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130. Development and implementation of a quality control protocol for B-mode ultrasound equipment.
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Tsapaki V, Tsalafoutas IA, Triantopoulou SS, and Triantopoulou C
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- Humans, Phantoms, Imaging, Quality Control, Ultrasonography, Review Literature as Topic, Transducers
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Purpose: Quality assurance (QA) of ultrasound (US) equipment is currently required in only a few countries around the world. In Greece, no national or other norms exist for regulating the use of US equipment. However, to obtain accreditation for the radiology department of a Greek hospital, the establishment and implementation of a quality control (QC) protocol and a QA programme for US equipment was required., Materials and Methods: A literature review regarding US QC/QA procedures was performed. The information collected was used as a guide to create a QC/QA protocol and to obtain an appropriate US QC phantom. Drafting and testing of the initial protocol lasted 6 months. Its final version was implemented for 18 months in two US systems and five US transducers., Results: The QC tests included in the protocol evaluate mechanical and electrical safety, image display, uniformity, penetration depth, distance accuracy, greyscale display, anechoic object imaging, geometric distortion, and axial/lateral resolution. The only QC test that failed was the test for uniformity since intense non-uniformities were observed that led to the replacement of two linear transducers., Conclusion: US imaging is considered safe and, where appropriate, is preferred over imaging modalities that use ionizing radiation. However, the lack of QC/QA implies that US image quality is not routinely monitored. Therefore, the possibility of malfunctions that may go undetected and lead to wrong diagnosis cannot be excluded. A QC/QΑ programme can contribute to the elimination of such errors and ensure that performance is maintained over time., (© 2021. Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB).)
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- 2022
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131. The Biggest Challenges Resulting from the COVID-19 Pandemic on Gender-Related Work from Home in Biomedical Fields-World-Wide Qualitative Survey Analysis.
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Bezak E, Carson-Chahhoud KV, Marcu LG, Stoeva M, Lhotska L, Barabino GA, Ibrahim F, Kaldoudi E, Lim S, Marques da Silva AM, Tan PH, Tsapaki V, and Frize M
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- Adult, Child, Communicable Disease Control, Female, Humans, Male, Pandemics, SARS-CoV-2, Teleworking, COVID-19 epidemiology
- Abstract
(1) Background: This paper aims to present and discuss the most significant challenges encountered by STEM professionals associated with remote working during the COVID-19 lockdowns. (2) Methods: We performed a qualitative analysis of 921 responses from professionals from 76 countries to the open-ended question: "What has been most challenging during the lockdown for you, and/or your family?" (3) Findings: Participants reported challenges within the immediate family to include responsibilities for school, childcare, and children's wellbeing; and the loss of social interactions with family and friends. Participants reported increased domestic duties, blurred lines between home and work, and long workdays. Finding adequate workspace was a problem, and adaptations were necessary, especially when adults shared the same setting for working and childcare. Connectivity issues and concentration difficulties emerged. While some participants reported employers' expectations did not change, others revealed concerns about efficiency. Mental health issues were expressed as anxiety and depression symptoms, exhaustion and burnout, and no outlets for stress. Fear of becoming infected with COVID-19 and uncertainties about the future also emerged. Pressure points related to gender, relationship status, and ethnicities were also evaluated. Public policies differed substantially across countries, raising concerns about the adherence to unnecessary restrictions, and similarly, restrictions being not tight enough. Beyond challenges, some benefits emerged, such as increased productivity and less time spent getting ready for work and commuting. Confinement resulted in more quality time and stronger relationships with family. (4) Interpretation: Viewpoints on positive and negative aspects of remote working differed by gender. Females were more affected professionally, socially, and personally than males. Mental stress and the feeling of inadequate work efficiency in women were caused by employers' expectations and lack of flexibility. Working from home turned out to be challenging, primarily due to a lack of preparedness, limited access to a dedicated home-office, and lack of previous experience in multi-layer/multi-scale environments.
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- 2022
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132. Women in Medical Physics and Biomedical Engineering: past, present and future.
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Frize M, Tsapaki V, Lhotska L, da Silva AMM, Ibrahim F, Bezak E, Stoeva M, Barabino G, Lim S, Kaldoudi E, Tan PH, and Marcu LG
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Women in Medical Physics and Biomedical Engineering (WiMPBME) is a Task Group established in 2014 under the International Union of Physical and Engineering Scientists in Medicine (IUPESM). The group's main role is to identify, develop, implement, and coordinate various tasks and projects related to women's needs and roles in medical physics and biomedical engineering around the world. The current paper summarizes the past, present and future goals and activities undertaken or planned by the Task group in order to motivate, nurture and support women in medical physics and biomedical engineering throughout their professional careers. In addition, the article includes the historical pathway followed by various women's groups and subcommittees from 2004 up to the present day and depicts future aims to further these professions in a gender-balanced manner., Competing Interests: Conflict of interestnone., (© The Author(s) under exclusive licence to International Union for Physical and Engineering Sciences in Medicine (IUPESM) 2022.)
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- 2022
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133. Radiation dose and diagnostic reference levels for four interventional radiology procedures: results of the prospective European multicenter survey EUCLID.
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Schegerer AA, Frija G, Paulo G, Jaschke W, Tsapaki V, Repussard J, and Damilakis J
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- Diagnostic Reference Levels, Humans, Prospective Studies, Radiation Dosage, Radiology, Interventional, Surveys and Questionnaires, Carcinoma, Hepatocellular, Chemoembolization, Therapeutic, Liver Neoplasms
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Objectives: To assess information reflecting radiation dose and define diagnostic reference levels (DRL) on a European basis for four interventional radiology (IR) procedures considering clinical indication, anatomical region, and procedure., Methods: A prospective European study was performed to provide data on the IR procedures percutaneous recanalization of iliac arteries, percutaneous recanalization of femoropopliteal arteries, transarterial chemoembolization of hepatocellular carcinoma, and percutaneous transhepatic biliary drainage. Hospitals were asked to complete a questionnaire giving information on procedure, equipment, and protocol. Patient size and weight, experience of the operator graded in number of procedures performed, and complexity level of each procedure were reported. Sixteen hospitals from 13 countries could be surveyed. The percentiles of the kerma-area product, fluoroscopy time, cumulative air kerma at the interventional reference point, and number of images were determined. The impact of equipment, year of installation, and complexity level of the procedure on dose were analyzed., Results: DRLs based on clinical indication were defined. Dose values varied considerably within hospitals, between them, and within each subgroup of complexity level. The use of state-of-the-art equipment reduced dose significantly by 52%. Although dose also varied within each subgroup of complexity level, for transarterial chemoembolization of hepatocellular carcinoma and percutaneous transhepatic biliary drainage, dose significantly correlated with complexity., Conclusions: This was the first study reporting exposure practice and defining DRLs based on clinical indication for four IR procedures on a European basis. These DRLs can serve as a baseline for comparison with local practice, the study as a guideline for future surveys., Key Points: • The use of state-of-the-art angiographic equipment reduces dose significantly. • A significant correlation between radiation dose and complexity level is found. • Dose values vary considerably, both within and between individual hospitals, and within each complexity level of interventional radiology procedure., (© 2021. European Society of Radiology.)
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- 2021
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134. The IAEA remote and automated quality control methodology for radiography and mammography.
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Mora P, Pfeiffer D, Zhang G, Bosmans H, Delis H, Razi Z, Arreola M, and Tsapaki V
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- Humans, International Agencies, Phantoms, Imaging, Quality Control, Mammography, Nuclear Energy
- Abstract
Radiography remains the most widely used imaging modality throughout the world. Additionally, while it has been demonstrated that a quality control (QC) program, especially in mammography, improves image quality, weekly technologist QC testing might be lacking even where there is clinical qualified medical physicist (CQMP) support. Therefore, the International Atomic Energy Agency (IAEA) developed simple QC phantoms that can easily be used on a regular basis (daily/weekly) for radiography and mammography. These are simple in design and use materials that are easily accessible in most parts of the world. A software application is also developed that automatically analyzes images and Digital Imaging and Communications in Medicine (DICOM) header information. It exports data to a comma-separated values (CSV) file that is read by a Microsoft Excel® spreadsheet for documentation and graphical analysis. The phantom and the software were tested in four institutions (in Costa Rica and the United States of America) both on computed radiography and direct digital mammography and radiography systems. Data were collected over a 3-year period. No corrective actions were taken on the data, but service was performed on two of the units. Results demonstrated noise that could be attributed to suboptimal placement of the phantom and incorrect data being put into the DICOM header. Preliminary evaluation of the IAEA methodology has demonstrated that it can provide meaningful QC data that are sensitive to changes in the imaging systems. Care must be taken at implementation to properly train personnel and ensure that the image data, including the DICOM header, are being correctly transmitted. The methodology gives the opportunity for a single CQMP to provide QC services even to remote sites where travel is prohibitive, and it is feasible and easy to implement., (© 2021 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)
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- 2021
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135. CT diagnostic reference levels based on clinical indications: results of a large-scale European survey.
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Tsapaki V, Damilakis J, Paulo G, Schegerer AA, Repussard J, Jaschke W, and Frija G
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- Adult, Child, Preschool, Europe, Humans, Prospective Studies, Radiation Dosage, Reference Values, Diagnostic Reference Levels, Tomography, X-Ray Computed
- Abstract
Objectives: The objective of this study was to investigate the feasibility of defining diagnostic reference levels (DRLs) on a European basis for specific clinical indications (CIs), within the context of the European Clinical DRLs (EUCLID) European Commission project., Methods: A prospective, multicenter, industry-independent European study was performed to provide data on 10 CIs (stroke, chronic sinusitis, cervical spine trauma, pulmonary embolism, coronary calcium scoring, coronary angiography, lung cancer, hepatocellular carcinoma, colic/abdominal pain, and appendicitis) via an online survey that included information on patient clinical, technical, and dosimetric parameters. Data from at least 20 patients per CI were requested from each hospital. To establish DRLs, a methodology in line with the International Commission on Radiological Protection (ICRP) Report 135 good practice recommendations was followed., Results: Data were collected from 19 hospitals in 14 European countries on 4299 adult patients and 10 CIs to determine DRLs. DRLs differ considerably between sites for the same CI. Differences were attributed mainly to technical protocol and variable number of phases/scan lengths. Stroke and hepatocellular carcinoma were the CIs with the highest DRLs. Coronary calcium scoring had the lowest DRL value. Comparison with published literature was limited, as there was scarce information on DRLs based on CI., Conclusions: This is the first study reporting on feasibility of establishing CT DRLs based on CI using European data. Resulting values will serve as a baseline for comparison with local radiological practice, national authorities when DRLs are set/updated, or as a guideline for local DRL establishment., Key Points: • First study reporting on the feasibility of establishing CT diagnostic reference levels based on clinical indication using data collected across Europe. • Only one-fourth of the hospitals had CT machines less than 5 years old. • Large dose variations were observed among hospitals and CT protocols were quite different between hospitals.
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- 2021
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136. The impact of COVID-19 pandemic on gender-related work from home in STEM fields-Report of the WiMPBME Task Group.
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Frize M, Lhotska L, Marcu LG, Stoeva M, Barabino G, Ibrahim F, Lim S, Kaldoudi E, Marques da Silva AM, Tan PH, Tsapaki V, and Bezak E
- Abstract
The COVID-19 pandemic has forced many people, including those in the fields of science and engineering, to work from home. The new working environment caused by the pandemic is assumed to have a different impact on the amount of work that women and men can do from home. Particularly, if the major burden of child and other types of care is still predominantly on the shoulders of women. As such, a survey was conducted to assess the main issues that biomedical engineers, medical physicists (academics and professionals), and other similar professionals have been facing when working from home during the pandemic. A survey was created and disseminated worldwide. It originated from a committee of International Union for Physical and Engineering Sciences in Medicine (IUPESM; Women in Medical Physics and Biomedical Engineering Task Group) and supported by the Union. The ethics clearance was received from Carleton University. The survey was deployed on the Survey Monkey platform and the results were analyzed using IBM SPSS software. The analyses mainly consisted of frequency of the demographic parameters and the cross-tabulation of gender with all relevant variables describing the impact of work at home. A total of 921 responses from biomedical professions in 76 countries were received: 339 males, 573 females, and nine prefer-not-to-say/other. Regarding marital/partnership status, 85% of males were married or in partnership, and 15% were single, whereas 72% of females were married or in partnership, and 26% were single. More women were working from home during the pandemic (68%) versus 50% of men. More men had access to an office at home (68%) versus 64% for women. The proportion of men spending more than 3 h on child care and schooling per day was 12%, while for women it was 22%; for household duties, 8% of men spent more than 3 h; for women, this was 12.5%. It is interesting to note that 44% of men spent between 1 and 3 h per day on household duties, while for women, it was 55%. The high number of survey responses can be considered excellent. It is interesting to note that men participate in childcare and household duties in a relatively high percentage; although this corresponds to less hours daily than for women. It is far more than can be found 2 and 3 decades ago. This may reflect the situation in the developed countries only-as majority of responses (75%) was received from these countries. It is evident that the burden of childcare and household duties will have a negative impact on the careers of women if the burden is not more similar for both sexes. It is important to recognize that a change in policies of organizations that hire them may be required to provide accommodation and compensation to minimize the negative impact on the professional status and career of men and women who work in STEM fields., Competing Interests: The authors declare that there are no conflict of interests.Data available on request due to privacy/ethical restrictions: The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions., (© 2021 John Wiley & Sons Ltd.)
- Published
- 2021
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137. Evaluation of image quality and patient exposure in fluoroscopy using a phantom: Is there any clinical relevance?
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Tsalafoutas IA, Tsapaki V, and Triantopoulou I
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- Fluoroscopy, Humans, Phantoms, Imaging, Radiation Dosage, Image Processing, Computer-Assisted, Radiation Exposure
- Abstract
Objective: To investigate the impact of X-ray preset acquisition protocol settings on fluoroscopy image quality (IQ) and radiation exposure., Materials & Methods: A quality control (QC) phantom was imaged with a modern digital C-arm system, using various preset fluoroscopy protocols. IQ was assessed using human observers and in-house software for automated evaluation, based on contrast-to-noise ratios of details and their background. Patient radiation exposure was evaluated using the displayed Incident Air-Kerma and Kerma-Area Product values., Results: Protocol selection affects radiation exposure by a factor of about 3. IQ evaluation showed that acquisition protocols produce images with quite different characteristics. The visual IQ evaluation method was time consuming and cumbersome. The automated method, utilized the visual IQ evaluation results for calibration of detection thresholds. However, it failed to reproduce these results for all images and details types. In some images, digital image processing created artifacts which affected the pixel value distributions around details in a way that could be handled only by the human vision., Conclusion: Manufacturers provide many preset protocols designated for specific clinical uses, which have large impact on IQ characteristics and radiation exposure. However, protocol settings' selection rationale is essentially a "black box" for the end user. Though QC phantoms are currently used for IQ evaluation, they are not appropriate for drawing firm conclusions concerning the expected performance of each protocol in clinical practice. Currently, there is no consensus on the optimum technical characteristics of preset protocols for specific procedures. More work is needed in this area., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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138. Radiation dose management systems-requirements and recommendations for users from the ESR EuroSafe Imaging initiative.
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Loose RW, Vano E, Mildenberger P, Tsapaki V, Caramella D, Sjöberg J, Paulo G, Torresin A, Schindera S, Frija G, and Damilakis J
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- Diagnostic Imaging, Humans, Radiation Dosage, Radiometry, Radiation Protection, Radiology
- Abstract
The European Directive 2013/59/Euratom requires member states of the European Union to ensure justification and optimisation of radiological procedures and store information on patient exposure for analysis and quality assurance. The EuroSafe Imaging campaign of the European Society of Radiology created a working group (WG) on "Dose Management" with the aim to provide European recommendations on the implementation of dose management systems (DMS) in clinical practice. The WG follows Action 4: "Promote dose management systems to establish local, national, and European diagnostic reference levels (DRL)" of the EuroSafe Imaging Call for Action 2018. DMS are designed for medical practitioners, radiographers, medical physics experts (MPE) and other health professionals involved in imaging to support their tasks and duties of radiation protection in accordance with local and national requirements. The WG analysed requirements and critical points when installing a DMS and classified the individual functions at different performance levels. KEY POINTS: • DMS are very helpful software tools for monitoring patient exposure, optimisation, compliance with DRLs and quality assurance. • DMS can help to fulfil dosimetric aspects of the European Directive 2013/59/Euratom. • The EuroSafe WG analyses DMS requirements and gives recommendations for users.
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- 2021
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139. A simple manual method to estimate water-equivalent diameter for calculating size-specific dose estimate in chest computed tomography.
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Mihailidis D, Tsapaki V, and Tomara P
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- Humans, Radiography, Thoracic statistics & numerical data, Tomography, X-Ray Computed statistics & numerical data, Water, Lung anatomy & histology, Radiation Dosage, Radiography, Thoracic methods, Tomography, X-Ray Computed methods
- Abstract
Objectives: The American Association of Physicists in Medicine (AAPM) Task Groups (TG) 204 and 220 introduced a method to estimate patient dose by introducing the Size-Specific Dose Estimate (SSDE). They provided patient size-specific conversion factors that could be applied to volumetric CT Dose Index CTDI
vol to estimate patient dose in terms of SSDE based on either effective diameter (Deff ) or water equivalent diameter (Dw ). Our study presented an alternative method to manually estimate SSDE for the everyday clinical routine chest CT that can be readily used and does not require sophisticated computer programming., Methods: For 16 adult patients undergoing chest CT, the method employed an average relative electron density (ρe lung = 0.3) for the lung tissue and a ρe tissue of 1.0 for the other tissues to scale the lateral thickness and compute the effective lateral thickness on the patient's axial image. The proposed method estimated a "corrected" Deff (Deff corr ) to replace Dw and compared results with TG220 and a second method proposed by Huda et al, for the same set of CT studies., Results: The results showed comparable behavior for all methods. There is overall agreement especially between this study and TG220. Largest differences were +13.3% and+15.9% from TG220 and Huda values, respectively. Patient size correlation showed strong correlation with the TG220 and Huda et al methods., Conclusions: A simple, quick manual method to estimate CT patient radiation dose in terms of SSDE was proposed as an alternative where sophisticated computer programming is not available. It can be readily used during any clinical chest CT scanning., Advances in Knowledge: The paper is novel as it presents simple, quick manual method to estimate CT patient radiation dose in chest imaging. The process can be used as alternative in cases no sophisticated computer programming is available.- Published
- 2021
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140. Radiation dose optimization in diagnostic and interventional radiology: Current issues and future perspectives.
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Tsapaki V
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- Humans, Radiation Dosage, Radiography, Tomography, X-Ray Computed, Radiographic Image Enhancement, Radiology, Interventional
- Abstract
The medical radiological imaging technological evolution and wide availability has resulted in the exponential increase in utilization. Evidence for a risk of cancer arising from radiation doses of lower than 100 mSv is still limited. There is a need for patient dose optimization. A literature review was conducted to identify the reasons why optimization is important and the steps to be followed for a successful optimization process in digital radiology, Computed Tomography, interventional radiology and mammography. Based on recent literature, 5 steps for a dose optimization process are proposed. These steps are: 1) establishment of a quality assurance programme; a mistake, misuse or malfunction of an X-ray machine can potentially affect the health or life of thousands of people, 2) establishment of a dose optimization team consisting of a radiologist, medical physicist and radiation technologist, 3) determination of baseline dose levels and image quality as well as comparisons with benchmarks to decide which exam protocols should be optimized, 4) modification of protocols by the medical physicist and 5) evaluation of the optimization process and its effect on patient dose and image quality. The optimization process should include joint efforts focused on 1) equipment performance 2) exam protocol customization and 3) staff behaviour. Manufacturers should provide detailed descriptions of exam protocols and training on the use of dose reduction features. The diagnostic radiology medical physicist should emerge and take a proactive lead in the everyday clinical routine in order to promote the value of optimization process., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2020
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141. Towards establishment of diagnostic reference levels based on clinical indication in the state of Qatar.
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AlNaemi H, Tsapaki V, Omar AJ, AlKuwari M, AlObadli A, Alkhazzam S, Aly A, and Kharita MH
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Objectives: The objectives of this study were to: 1) evaluate patient radiation exposure in CT and 2) establish CT Diagnostic Reference Levels (DRL)s based on clinical indication (CI) in Qatar., Materials and Methods: Patient data for 13 CIs were collected using specially designed collection forms from the dose management software (DMS) of Hamad Medical Corporation (HMC), the main Qatar healthcare provider. The methodology described in the International Commission on Radiological Protection (ICRP) Report 135 was followed to establish national clinical DRLs in terms of Volumetric Computed Tomography Dose Index (CTDIvol) and total Dose Length Product (DLPt). Effective dose (Ef) was estimated by DMS using DLPt and appropriate conversion factors and was analyzed for comparison purposes., Results: Data were retrospectively collected for 896 adult patients undergoing CT examinations in 4 hospitals and 7 CT scanners. CT for Diffuse infiltrative lung disease imparted the lowest radiation in terms of CTDIvol (5 mGy), DLPt (181 mGy.cm) and Ef (3.6 mSv). Total body CT for severe trauma imparted the highest DLPt (3137 mGy.cm) and Ef (38.6 mSv) of all CIs with a CTDIvol of 15 mGy. Rounded Third quartile CTDIvol and DLPt values were defined as the Qatar CT clinical DRLs. Comparison was limited due to sparse international literature. When this was possible data were lower or comparable with other studies., Conclusions: This is the first study reporting national clinical DRLs in Asia and second one internationally after UK. For accurate comparison between studies, systemized CI nomenclature must be followed by researchers., Competing Interests: The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article., (© 2020 The Authors.)
- Published
- 2020
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142. ADULT CT EXAMINATIONS IN ALGERIA: TOWARDS UPDATING NATIONAL DIAGNOSTIC REFERENCE LEVELS.
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Khelassi-Toutaoui N, Merad A, Tsapaki V, Meddad F, Sakhri-Brahimi Z, Guedioura D, and Saadi S
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- Adult, Algeria, Humans, Pilot Projects, Radiation Dosage, Reference Values, Diagnostic Reference Levels, Tomography, X-Ray Computed
- Abstract
A pilot study has concerned the most frequent computed tomography examinations (CT). This represents the first results based on actual survey for diagnostic reference levels (DRLs) establishment in Algeria. A total number of 2540 patients underwent this survey that has included the recording of CT parameters, computed tomography dose index (CTDIvol) and dose-length product of the head, thorax, abdomen, abdomen-pelvis (AP), lumbar spine (LS) and thorax-abdomen-pelvis (TAP) performed on standard patients. The proposed DRLs are 71 mGy/1282 mGy.cm for head, 16 mGy/555 mGy.cm for thorax, 18 mGy/671 mGy.cm for abdomen, 21 mGy/950 mGy.cm for AP, 36 mGy/957 mGy.cm for LS and 18 mGy/994 mGy.cm for TAP. The rounded 75th percentile seems to be higher in some examinations compared to the literature. Our findings confirm the need to optimise our practice. These results provide a starting point for institutional evaluation of CT radiation doses., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2020
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143. Diagnostic Reference Levels based on clinical indications in computed tomography: a literature review.
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Paulo G, Damilakis J, Tsapaki V, Schegerer AA, Repussard J, Jaschke W, and Frija G
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Background: In August 2017, the European Commission awarded the "European Study on Clinical Diagnostic Reference levels for X-ray Medical Imaging" project to the European Society of Radiology, to provide up-to-date Diagnostic Reference Levels based on clinical indications. The aim of this work was to conduct an extensive literature review by analysing the most recent studies published and the data provided by the National Competent Authorities, to understand the current situation regarding Diagnostic Reference Levels based on clinical indications for computed tomography., Results: The literature review has identified 23 papers with Diagnostic Reference Levels based on clinical indications for computed tomography from 15 countries; 12 of them from Europe. A total of 28 clinical indications for 6 anatomical areas (head, cervical spine/neck, chest, abdomen, abdomen-pelvis, chest-abdomen-pelvis) have been identified., Conclusions: In all the six anatomical areas for which Diagnostic Reference Levels based on clinical indications were found, a huge variation of computed tomography dose descriptor values was identified, providing evidence for a need to develop strategies to standardise and optimise computed tomography protocols.
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- 2020
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144. Leadership and mentoring in medical physics: The experience of a medical physics international mentoring program.
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Santos JC, Goulart LF, Giansante L, Lin YH, Sirico ACA, Ng AH, Tsapaki V, Bezak E, and Ng KH
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- Humans, Leadership, Physics, Program Evaluation, Mentoring, Mentors
- Abstract
Mentoring aims to improve careers and create benefits for the participants' personal and professional lives. Mentoring can be an individual or a shared experience for a group, while the mentor's role remains the same in both models. Mentors should increase confidence, teach, inspire, and set examples, helping the mentees to mould their path, contributing to the pursuit of their personal and professional goals. This study aims to report on the experience of early-career medical physics professionals and postgraduate students participating in a global mentoring program and to assess the impact of this activity on their professional development. The objectives of this mentoring program are to develop leadership roles among young medical physicists and to provide guidance and support. An online questionnaire was administered to the mentee participants. The analysis of their responses is reported in this work and the current status of the programme was examined using a SWOT analysis. In general, the mentoring experience had a positive impact on the mentees. The mentors were found especially helpful in the decision-making situations and in other conflicts that may arise with career development. Additionally, the mentees felt that mentoring contributed to the development of leadership skills required for the job market and assist in personal development. This paper concludes that participation of young medical physicists in a mentoring group program is beneficial to their career and therefore should be encouraged., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)
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- 2020
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145. Solutions to Gender Balance in STEM Fields Through Support, Training, Education and Mentoring: Report of the International Women in Medical Physics and Biomedical Engineering Task Group.
- Author
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Barabino G, Frize M, Ibrahim F, Kaldoudi E, Lhotska L, Marcu L, Stoeva M, Tsapaki V, and Bezak E
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- Advisory Committees, Female, Humans, Internationality, Research Report, Biomedical Engineering organization & administration, Gender Equity, Leadership, Mentoring, Physics organization & administration, Women
- Abstract
The aim of this article is to offer a view of the current status of women in medical physics and biomedical engineering, while focusing on solutions towards gender balance and providing examples of current activities carried out at national and international levels. The International Union of Physical and Engineering Scientists in Medicine is committed to advancing women in science and health and has several initiatives overseen by the Women in Medical Physics and Biomedical Engineering Task Group. Some of the main strategies proposed by the Task Group to attain gender balance are: (a) identify and promote female role models that achieve successful work-life balance, (b) establish programs to develop female leaders, (c) create opportunities for females to increase the international visibility within the scientific community, and (d) establish archives and databases of women in STEM.
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- 2020
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146. CONE BEAM CT IN DENTAL IMPLANT PLANNING: HOW CLOSE ARE PATIENT DOSIMETRY RESULTS WITH DATA FROM PHANTOM STUDIES FOUND IN LITERATURE?
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Kottou S, Zapros A, Stefanopoulou N, Krompas N, and Tsapaki V
- Subjects
- Cone-Beam Computed Tomography instrumentation, Humans, Image Interpretation, Computer-Assisted methods, Radiation Dosage, Cone-Beam Computed Tomography methods, Dental Implantation methods, Dental Implants standards, Patient Care Planning standards, Phantoms, Imaging, Thermoluminescent Dosimetry methods
- Abstract
Advantages of Cone Beam Computed Tomography (CBCT) include high-quality 3D imaging and reduced radiation exposure with relatively low cost. In this study, patient radiation exposure in CBCT implant planning dentistry was measured in terms of Kerma Area Product (KAP). Data were obtained from 217 CBCT scans on 168 individuals using a CS9300 Carestream system. Scans were made using 80-90 kVp, 4-5 mA, 8 and 13.3 s exposure time (depending on voxel size) and a fixed field of view (FOV) of 10 × 10 cm2 (medium). Mean KAP was estimated using two voxel sizes 180 × 180 × 180 μm3 and 200 × 200 × 200 μm3 and found to be 399 and 314 mGycm2, respectively. Corresponding KAP values found in literature ranged between 210 and 2140 mGycm2. Mean E was estimated using conversion coefficient factors found in literature, according to FOV size and tube voltage value and found to range between 24 and 161 μSv., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2019
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147. Dose management software implementation in mammography.
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Samara ET, Tsapaki V, and Sramek D
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- Aged, Female, Humans, Middle Aged, Radiometry, Mammography methods, Radiation Dosage, Software
- Abstract
Purpose: This work aimed to evaluate the use of a dose management software (DMS) in mammography and analyse the clinical practice in terms of radiation exposure in screening and diagnostic mammography., Methods: Mean glandular dose (MGD) from approximately 10,000 images were collected and analysed taking into account anode/filter combination, projection, compressed breast thickness (CBT) and compression force. Causes of increased MGD were investigated and actions were taken when malpractice was detected., Results: MGD values for craniocaudal (CC) and mediolateral oblique (MLO) exposures for different CBT were defined. The average MGD for CBT of 60-69 mm was 1.84 mGy for CC images and 1.85 mGy for MLO images for screening examinations, while for diagnostic examinations the MGD was 1.95 mGy for CC and 2.01 mGy for MLO images. As no national diagnostic reference levels (DRLs) for mammography exist in Switzerland, typical mean glandular dose (MGD) values were defined as a first step towards their establishment for both screening and diagnostic examinations., Conclusions: The use of DMS facilitated immensely the analysis of all clinical and technical parameters, the evaluation of radiation dose received by the patients, as well as the overall evaluation of radiographers' performance. The DMS disclosed the role of the medical physicist in dose management and optimization., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2019
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148. Gender-related differences in side-effects and hemodynamic response to regadenoson in patients undergoing SPECT myocardial perfusion imaging.
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Katsikis A, Kyrozi E, Manira V, Theodorakos A, Malamitsi J, Tsapaki V, Iakovou I, Voudris V, Kolovou G, and Koutelou M
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- Adult, Aged, Aged, 80 and over, Female, Heart Rate drug effects, Humans, Male, Middle Aged, Stroke Volume, Hemodynamics drug effects, Myocardial Perfusion Imaging, Purines adverse effects, Pyrazoles adverse effects, Sex Characteristics, Tomography, Emission-Computed, Single-Photon
- Abstract
Purpose: To evaluate differences in side-effects and hemodynamic response between men and women undergoing regadenoson-stress SPECT myocardial perfusion imaging (MPI)., Methods: The initial population of the study included 858 consecutive patients who underwent regadenoson-stress MPI at our institution. These patients underwent prospective assessment and classification of regadenoson-induced side-effects in six categories and recording of heart rate (HR) and blood pressure (BP) before and after regadenoson administration. From this initial population, after adjustment with 1:1 propensity matching using gender as the dependent variable and age, BMI, diabetes mellitus, hypertension, smoking, presence of coronary artery disease, LVEF, baseline systolic and diastolic blood pressure (BP) and HR, on-going use of cardio-active medications during test, and abnormal MPI scan as independent variables, a population of 279 pairs of opposite gender was formed and studied., Results: Compared with men, women had a significantly higher rate of any side-effect (71% vs. 58%, p = 0.002), chest pain (23% vs. 12%, p < 0.001), gastrointestinal discomfort (20% vs. 12%, p = 0.01), dizziness (12% vs. 5%, p = 0.002), and headache (20% vs. 13%, p = 0.03) and similar rates of dyspnea and other side-effects. Women demonstrated a higher median HR-response compared with men (41% (- 8, 127) vs. 34% (- 5, 106), p = 0.001) while men demonstrated a lower median systolic BP response (- 3% (- 27, 48) vs. 0% (- 36, 68), p = 0.02) compared with women., Conclusions: Gender is independently associated with a differential response to regadenoson with regard to overall side-effects and HR-response. These observations have the potential of important management and prognostic implications respectively.
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- 2019
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149. Development of breast lesions models database.
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Bliznakova K, Dukov N, Feradov F, Gospodinova G, Bliznakov Z, Russo P, Mettivier G, Bosmans H, Cockmartin L, Sarno A, Kostova-Lefterova D, Encheva E, Tsapaki V, Bulyashki D, and Buliev I
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- Cadaver, Female, Humans, Image Processing, Computer-Assisted, Tomography, X-Ray Computed, Breast Neoplasms diagnostic imaging, Databases, Factual
- Abstract
Purpose: We present the development and the current state of the MaXIMA Breast Lesions Models Database, which is intended to provide researchers with both segmented and mathematical computer-based breast lesion models with realistic shape., Methods: The database contains various 3D images of breast lesions of irregular shapes, collected from routine patient examinations or dedicated scientific experiments. It also contains images of simulated tumour models. In order to extract the 3D shapes of the breast cancers from patient images, an in-house segmentation algorithm was developed for the analysis of 50 tomosynthesis sets from patients diagnosed with malignant and benign lesions. In addition, computed tomography (CT) scans of three breast mastectomy cases were added, as well as five whole-body CT scans. The segmentation algorithm includes a series of image processing operations and region-growing techniques with minimal interaction from the user, with the purpose of finding and segmenting the areas of the lesion. Mathematically modelled computational breast lesions, also stored in the database, are based on the 3D random walk approach., Results: The MaXIMA Imaging Database currently contains 50 breast cancer models obtained by segmentation of 3D patient breast tomosynthesis images; 8 models obtained by segmentation of whole body and breast cadavers CT images; and 80 models based on a mathematical algorithm. Each record in the database is supported with relevant information. Two applications of the database are highlighted: inserting the lesions into computationally generated breast phantoms and an approach in generating mammography images with variously shaped breast lesion models from the database for evaluation purposes. Both cases demonstrate the implementation of multiple scenarios and of an unlimited number of cases, which can be used for further software modelling and investigation of breast imaging techniques. The created database interface is web-based, user friendly and is intended to be made freely accessible through internet after the completion of the MaXIMA project., Conclusions: The developed database will serve as an imaging data source for researchers, working on breast diagnostic imaging and on improving early breast cancer detection techniques, using existing or newly developed imaging modalities., (Copyright © 2019. Published by Elsevier Ltd.)
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- 2019
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150. Management of difficult bile duct stones and indeterminate bile duct structures: Reduced ERCP radiation exposure with adjunct use of digital single-operator cholangioscopy.
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Tsapaki V, Papastergiou V, Giannakopoulos A, Angelogiannopoulou P, Delatolas V, Triantopoulou S, Theocharis S, and Paraskeva K
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- Aged, Female, Humans, Male, Retrospective Studies, Bile Ducts diagnostic imaging, Bile Ducts radiation effects, Cholangiopancreatography, Endoscopic Retrograde adverse effects, Gallstones diagnostic imaging, Radiation Exposure prevention & control
- Abstract
Introduction: Endoscopic Retrograde Cholangio-Pancreatography (ERCP) is an well-established endoscopic procedure for the management of biliary diseases. The use of fluoroscopy during ERCP has often raised concerns regarding potential risks from radiation exposure, particularly in complex cases. We investigated whether a new digital single-operator cholangioscopy (D-SOC) system, used adjunctively to ERCP, actually reduces patient radiation exposure., Materials and Methods: We retrospectively analyzed a prospective database (April 2016 to October 2018) including consecutive patients who underwent successful management of difficult-to-treat biliary stones or indeterminate biliary strictures by using either conventional ERCP (ERCP cohort) or ERCP in conjunction with D-SOC (ERCP/D-SOC cohort). The overall patient radiation exposure outcomes were compared in terms of Kerma Area Product (KAP), Fluoroscopy time (T) and the total number of films (F)., Results: Overall, 47 patients (mean 71.8 years, 59.6% males) were included (ERCP cohort = 29, ERCP/D-SOC cohort = 18), referred either for difficult bile duct stones (n = 36) or indeterminate biliary strictures (n = 11). The median KAP, T and F in the ERCP/D-SOC cohort were 12.3 Gycm
2 , 3.7 min and 4 films respectively, compared with 52.1 Gycm2 , 8.4 min, and 5 films respectively in the ERCP cohort. Statistically significant differences (P = 0.0001) were found for KAP and T., Conclusions: Adjunct use of a digital cholangioscopy platform appears to significantly reduce radiation exposure in patients undergoing ERCP for the management of difficult bile stones or indeterminate biliary strictures., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)- Published
- 2019
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