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PURPOSE: Patient-specific protocol optimisation in abdomino-pelvic Computed Tomography (CT) requires measurement of body habitus/size (BH), sensitivity-specificity (surrogates image quality (IQ) metrics) and risk (surrogates often dose quantities) (RD). This work provides an updated inventory of metrics available for each of these three categories of optimisation variables derivable directly from patient measurements or images. We consider objective IQ metrics mostly in the spatial domain (i.e., those related directly to sharpness, contrast, noise quantity/texture and perceived detectability as these are used by radiologists to assess the acceptability or otherwise of patient images in practice). MATERIALS AND METHODS: The search engine used was PubMed with the search period being 2010-2024. The key words used were: 'comput* tomography', 'CT', 'abdom*', 'dose', 'risk', 'SSDE', 'image quality', 'water equivalent diameter', 'size', 'body composition', 'habit*', 'BMI', 'obes*', 'overweight'. Since BH is critical for patient specific optimisation, articles correlating RD vs BH, and IQ vs BH were reviewed. RESULTS: The inventory includes 11 BH, 12 IQ and 6 RD metrics. 25 RD vs BH correlation studies and 9 IQ vs BH correlation studies were identified. 7 articles in the latter group correlated metrics from all three categories concurrently. CONCLUSIONS: Protocol optimisation should be fine-tuned to the level of the individual patient and particular clinical query. This would require a judicious choice of metrics from each of the three categories. It is suggested that, for increased utility in clinical practice, more future optimisation studies be clinical task based and involve the three categories of metrics concurrently.
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MPPs are trained in the branches of physics associated with the practice of medicine. Possessing a solid scientific background and technical skills, MPPs are well suited to play a leading role within each stage of a medical device life cycle. The various stages of the life cycle of a medical device include establishment of requirements with use-case assessment, investment planning, procurement of medical devices, acceptance testing especially regarding safety and performance, quality management, effective and safe use and maintenance, user training, interfacing with IT systems, and safe decommissioning and removal of the medical devices. Acting as an expert within the clinical staff of a healthcare organisation, the MPP can play an important role to achieve a balanced life cycle management of medical devices. Given that the functioning of medical devices and their clinical application in routine clinical practice and research is heavily physics and engineering based, the MPP is strongly associated with the hard science aspects and advanced clinical applications of medical devices and associated physical agents. Indeed, this is reflected in the mission statement of MPP professionals [1]. PURPOSE: The life cycle management of medical devices is described as well as the procedures involved. These procedures are performed by multi-disciplinary teams within a healthcare environment. The task of this workgroup was focused on clarifying and elaborating the role of the Medical Physicist and Medical Physics Expert - here collectively referred to as the Medical Physics Professional (MPP) - within these multi-disciplinary teams. This policy statement describes the role and competences of MPPs in every stage of a medical device life cycle. If MPPs are an integral part of these multi-disciplinary teams, the effective use, safety, and sustainability of the investment is likely to improve as well as the overall service quality delivered by the medical device during its life cycle. It leads to better health care quality and reduced costs. Furthermore, it gives MPPs a stronger position in health care organisations throughout Europe.
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Medicina , Física , Humanos , Europa (Continente) , Calidad de la Atención de Salud , Políticas , Física Sanitaria/educaciónRESUMEN
PURPOSE: Calculation of the Size Specific Dose Estimate (SSDE) requires accurate delineation of the skin boundary of patient CT slices. The AAPM recommendation for SSDE evaluation at every CT slice is too time intensive for manual contouring, prohibiting real-time or bulk processing; an automated approach is therefore desirable. Previous automated delineation studies either did not fully disclose the steps of the algorithm or did not always manage to fully isolate the patient. The purpose of this study was to develop a validated, freely available, fast, vendor-independent open-source tool to automatically and accurately contour and calculate the SSDE for the abdomino-pelvic region for entire studies in real-time, including flagging of patient-truncated images. METHODS: The Python tool, CTContour, consists of a sequence of morphological steps and scales over multiple cores for speed. Tool validation was achieved on 700 randomly selected slices from abdominal and abdomino-pelvic studies from public datasets. Contouring accuracy was assessed visually by four medical physicists using a 1-5 Likert scale (5 indicating perfect contouring). Mean SSDE values were validated via manual calculation. RESULTS: Contour accuracy validation produced a score of four of five for 98.5 % of the images. A 300 slice exam was contoured and truncation flagged in 6.3 s on a six-core laptop. CONCLUSIONS: The algorithm was accurate even for complex clinical scenarios and when artefacts were present. Fast execution makes it possible to automate the calculation of SSDE in real time. The tool has been published on GitHub under the GNU-GPLv3 license.
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Abdomen , Tomografía Computarizada por Rayos X , Abdomen/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodosRESUMEN
From its inception, EFOMP has pursued a policy to improve and coordinate education and training of medical physicists across all its participating European countries. Several EFOMP policy statements on education and training have been published and surveys have been held to get an overview of the actual situation. At the beginning of 2020 a new survey was distributed amongst the 36 National Member Organizations (NMOs), in which questions were based on recommendations published in the most recent policy statements. Thirty-three of the NMOs (91%) responded, of which 22 indicated having a National Registration Scheme (NRS) for Medical Physics Experts (MPEs) in place. Another 6 indicated considering such a scheme. Results of the questionnaire showed that there was good correspondence between education and training programmes, i.e. a division between a BSc phase, an MSc phase and a clinical phase after completion of the MSc. Differences between NRSs were primarily seen in the availability and composition of a supervising committee and in the availability of guidelines for handling professional misconduct. In addition, some differences were seen in the topics that were part of the education and training programme. The goal of a universal (registered) MPE accepted by all European countries is still far away despite the progress being made. The new procedure for approving an existing NRS, which fulfils all EFOMP criteria is seen as an important step forward. Exchange of experience, knowledge, ideas and, above all, MPE trainees between European countries is seen as the best approach to achieve this goal.
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Curriculum , Educación Médica , Escolaridad , Europa (Continente) , Física , PolíticasRESUMEN
European Directive 2013/59/EURATOM requires the establishment and use of diagnostic reference levels (DRLs) for diagnostic and interventional procedures. The purpose of this study was to establish local DRLs for a major tertiary public hospital. As the hospital is the only such hospital in Malta, the same data collected for setting local DRLs can also be used for setting national DRLs, making local DRLs de facto national DRLs. A retrospective survey of cumulative kerma-area product (KAP) and fluoroscopy time data from the cardiac catheterisation laboratory and interventional radiology suites was carried out. The effect of system upgrades on cumulative KAP was also assessed. Local DRLs were set for common cardiology and interventional radiology procedures. All DRLs compare favourably with those in European literature. A Philips Allura Clarity upgrade to the cardiac catheterisation laboratories led to significant reductions in cumulative KAP (p ⪠0.05) for most procedures.
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Cardiología , Radiología Intervencionista , Fluoroscopía , Malta , Dosis de Radiación , Radiografía Intervencional , Valores de Referencia , Estudios RetrospectivosRESUMEN
Paediatric head computed tomography (CT) dose optimisation was carried out using three figure-of-merits (FOMs), based on tube voltage, current, noise, volumetric computed tomography dose index (CTDIvol) and contrast-to-noise ratio (CNR). FOM1: spatial resolution and total minimum contrast level (N) against CTDIvol; FOM2: noise against CTDIvol; FOM3: CNR against CTDIvol. Stage 1: Application of FOM1 and FOM2 on a Catphan without current modulation. Stage 2: CTDIvol and noise assessed on an anthropomorphic phantom with current modulation. Stage 3: All FOMs applied to Catphan images acquired with current modulation. Results indicated no single test case outperformed the current protocol (100 kVp, 200 mA) in all FOMs. Some test cases offered a reduction in dose at the cost of higher noise. The 120-kVp, 100-mA combination offered good compromise between dose and noise. Further investigation is required to determine whether this protocol could be added for procedures where higher noise is acceptable (e.g. craniosynostosis).
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Encéfalo/diagnóstico por imagen , Cabeza/diagnóstico por imagen , Fantasmas de Imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/normas , Tomografía Computarizada por Rayos X/normas , Antropometría , Niño , HumanosRESUMEN
Cyanidin-3-O-glucoside (C3G), the predominant anthocyanin in haskap berries (Lonicera caerulea L.), possesses antioxidant and many other biological activities. This study investigated the impact of temperature and pH on the degradation of the C3G-rich haskap fraction. The effect of the thermal degradation products on the viability of hepatocellular carcinoma HepG2 and breast cancer MDA-MB-231 cells was also studied in vitro. Using column chromatography, the C3G-rich fraction was isolated from acetone extracts of haskap berries. The C3G stability in these fractions was studied under elevated temperatures (70 °C and 90 °C) at three different pH values (2.5, 4, and 7) by monitoring the concentration of C3G and its major degradation products, protocatechuic acid (PCA) and phloroglucinaldehyde (PGA), using liquid chromatography mass spectrometry. Significant degradation of C3G was observed at elevated temperatures and at neutral pH. Conversely, the PCA and PGA concentration increased at higher pH and temperature. Similar to C3G, neutral pH also has a prominent effect on the degradation of PGA, which is further accelerated by heating. The C3G-rich fraction exhibited dose-dependent inhibitory effects on cell metabolic activity when the HepG2 cells were exposed for 48 h. Interestingly, PGA but not PCA exhibited cytotoxic effects against both MDA-MB-231 and HepG2 cells. The results suggest that thermal food processing of haskap could influence its biological properties due to the degradation of C3G.
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The traditional histology method typically employed by forensic anthropologists involves plastic embedding of undecalcified bone. The embedded sample is then cut by a diamond blade saw and ground to the required thickness of ~50-100 microns using a grinder. There are several limitations to this method: Cement lines may be blurred; depth-of-field artifacts may result from viewing thick sections; and medicolegal offices with limited budgets may not be able to invest in additional equipment or training for this method. A silver nitrate stain modification of the standard histology preparation technique of decalcified bone is presented. The benefits of this technique are that: Cement lines are viewed clearly; no depth-of-field artifacts are present; and because this is a modification of the standard technique used by histology laboratories typically employed by medicolegal offices, no additional equipment or training is required.