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1.
J Appl Clin Med Phys ; 25(4): e14285, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38317593

RESUMO

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.


Assuntos
Intensificação de Imagem Radiográfica , Software , Humanos , Doses de Radiação , Radiografia , Raios X , Imagens de Fantasmas
2.
J Appl Clin Med Phys ; 25(1): e14219, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38060709

RESUMO

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.


Assuntos
Energia Nuclear , Humanos , Inquéritos e Questionários
3.
Eur Radiol ; 32(8): 5525-5531, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35294584

RESUMO

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.


Assuntos
Proteção Radiológica , Fluoroscopia/métodos , Humanos , Doses de Radiação , Proteção Radiológica/métodos , Radiografia Intervencionista , Radiologia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos
4.
J Appl Clin Med Phys ; 23(12): e13823, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36345212

RESUMO

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.


Assuntos
Intensificação de Imagem Radiográfica , Software , Humanos , Intensificação de Imagem Radiográfica/métodos , Doses de Radiação , Imagens de Fantasmas
5.
Eur Radiol ; 31(12): 9346-9360, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33991223

RESUMO

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.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Níveis de Referência de Diagnóstico , Humanos , Estudos Prospectivos , Doses de Radiação , Radiologia Intervencionista , Inquéritos e Questionários
6.
Eur Radiol ; 31(7): 4459-4469, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33449177

RESUMO

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.


Assuntos
Níveis de Referência de Diagnóstico , Tomografia Computadorizada por Raios X , Adulto , Pré-Escolar , Europa (Continente) , Humanos , Estudos Prospectivos , Doses de Radiação , Valores de Referência
7.
Eur Radiol ; 31(4): 2106-2114, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32959080

RESUMO

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.


Assuntos
Proteção Radiológica , Radiologia , Diagnóstico por Imagem , Humanos , Doses de Radiação , Radiometria
8.
J Appl Clin Med Phys ; 22(11): 126-142, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34623023

RESUMO

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.


Assuntos
Mamografia , Energia Nuclear , Humanos , Agências Internacionais , Imagens de Fantasmas , Controle de Qualidade
9.
Sci Eng Ethics ; 26(1): 275-292, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30806940

RESUMO

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.


Assuntos
Engenharia Biomédica/organização & administração , Equidade de Gênero , Liderança , Tutoria , Física/organização & administração , Mulheres , Comitês Consultivos , Feminino , Humanos , Internacionalidade , Relatório de Pesquisa
10.
Eur J Nucl Med Mol Imaging ; 46(12): 2590-2600, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31414207

RESUMO

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.


Assuntos
Hemodinâmica/efeitos dos fármacos , Imagem de Perfusão do Miocárdio , Purinas/efeitos adversos , Pirazóis/efeitos adversos , Caracteres Sexuais , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico
11.
J Nucl Cardiol ; 21(6): 1213-22, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25189145

RESUMO

BACKGROUND: Although the use of myocardial perfusion imaging (MPI) for prognostic purposes in general population is well understood, its role in very elderly patients is not extensively studied. METHODS: 247 octgogenarians (79% male, 56% previous myocardial infarction-MI or revascularization) who underwent treadmill exercise testing (TET) with MPI were studied. TET and MPI-related data were registered per patient and prospective follow-up was performed to document all cause death (ACD), cardiac death (CD), non-fatal MI, and late revascularization (LR). Kaplan-Meier and Cox-regression analysis were used to compute event-free survival and identify significant predictors of these events. RESULTS: After 7.3 years there were 48 deaths, 17 CDs, 8 MIs, and 21 LRs. 69 patients were classified as high and 103 as low risk by SSS with annual cardiac mortality rates of 5% and 0.9%, respectively. Differences between survival curves of SSS-based risk groups were significant for ACD, CD, CD/MI, and CD/MI/LR. Summed stress (SSS) and difference scores were the only significant predictors of all endpoints. LVEF and transient ischemic LV dilatation were significant predictors of CD and CD/MI. LVEF and all MPI variables were associated with the CD, MI, and LR endpoint while only Duke treadmill score and angina severity demonstrated such a relationship among TET variables. CONCLUSIONS: In octogenarians, MPI provides effective long-term risk stratification for both hard (ACD, CD, CD/MI) and soft (CD/MI/LR) endpoints and should be preferred over simple TET.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Morte Súbita Cardíaca/epidemiologia , Teste de Esforço/estatística & dados numéricos , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Grécia/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Participação do Paciente/estatística & dados numéricos , Prevalência , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Taxa de Sobrevida
12.
Br J Radiol ; 97(1158): 1191-1201, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38711194

RESUMO

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.


Assuntos
Encéfalo , Cardiologistas , Cristalino , Exposição Ocupacional , Imagens de Fantasmas , Doses de Radiação , Humanos , Cristalino/efeitos da radiação , Encéfalo/efeitos da radiação , Encéfalo/diagnóstico por imagem , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Dosimetria Termoluminescente , Cardiologia , Radiografia Intervencionista/métodos
13.
Radiat Prot Dosimetry ; 200(8): 755-762, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702851

RESUMO

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.


Assuntos
Doses de Radiação , Humanos , Adulto , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Exposição à Radiação/análise , Malformações Arteriovenosas Intracranianas/radioterapia , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico por imagem , Níveis de Referência de Diagnóstico , Neurorradiografia/métodos , Idoso de 80 Anos ou mais , Adulto Jovem
14.
J Nucl Med ; 65(1): 125-131, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37884334

RESUMO

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 [177Lu]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.


Assuntos
Neoplasias , Compostos Radiofarmacêuticos , Humanos , Compostos Radiofarmacêuticos/uso terapêutico , Radiometria/métodos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Fígado
15.
Phys Eng Sci Med ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807011

RESUMO

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.

16.
J Ultrasound ; 25(2): 155-165, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33834366

RESUMO

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.


Assuntos
Literatura de Revisão como Assunto , Transdutores , Humanos , Imagens de Fantasmas , Controle de Qualidade , Ultrassonografia
17.
Health Technol (Berl) ; 12(3): 655-662, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399289

RESUMO

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.

18.
Artigo em Inglês | MEDLINE | ID: mdl-35270801

RESUMO

(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.


Assuntos
COVID-19 , Adulto , COVID-19/epidemiologia , Criança , Controle de Doenças Transmissíveis , Feminino , Humanos , Masculino , Pandemias , SARS-CoV-2 , Teletrabalho
19.
Br J Radiol ; 94(1117): 20200473, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33058736

RESUMO

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 CTDIvol 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 (ρelung = 0.3) for the lung tissue and a ρetissue 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 (Deffcorr) 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.


Assuntos
Pulmão/anatomia & histologia , Doses de Radiação , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Radiografia Torácica/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Água
20.
Gend Work Organ ; 28(Suppl 2): 378-396, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34230783

RESUMO

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.

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