Physical Image Quality Metrics for the Characterization of X-ray Systems Used in Fluoroscopy-Guided Pediatric Cardiac Interventional Procedures: A Systematic Review.

Pediatric interventional cardiology procedures are essential in diagnosing and treating congenital heart disease in children; however, they raise concerns about potential radiation exposure. Managing radiation doses and assessing image quality in angiographs becomes imperative for safe and effective interventions. This systematic review aims to comprehensively analyze the current understanding of physical image quality metrics relevant for characterizing X-ray systems used in fluoroscopy-guided pediatric cardiac interventional procedures, considering the main factors reported in the literature that influence this outcome. A search in Scopus and Web of Science, using relevant keywords and inclusion/exclusion criteria, yielded 14 relevant articles published between 2000 and 2022. The physical image quality metrics reported were noise, signal-to-noise ratio, contrast, contrast-to-noise ratio, and high-contrast spatial resolution. Various factors influencing image quality were investigated, such as polymethyl methacrylate thickness (often used to simulate water equivalent tissue thickness), operation mode, anti-scatter grid presence, and tube voltage. Objective evaluations using these metrics ensured impartial assessments for main factors affecting image quality, improving the characterization of fluoroscopic X-ray systems, and aiding informed decision making to safeguard pediatric patients during procedures.

Radiation dose reduction and image quality evaluation for lateral lumbar spine projection.

Purpose: Optimization studies in digital radiology help to reduce the radiological risk to patients and maximize the benefits associated with their clinical purpose. The aim of this study was to assess the optimization of lateral lumbar spine projection via a combination of exposure parameters adjustments and additional filtration using a sectional anthropomorphic phantom. Materials and methods: We evaluated the effects of peak voltage, tube loading, and low-cost filters made of copper, titanium, brass, and nickel on both the perceived and physical quality of 125 radiographs obtained in a computer radiography system. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with their Figure of Merit (FOM), based on the entrance surface air kerma with backscatter (ESAK), was used to assess physical image quality. Results: The standard image had a perceived image quality, SNR, FOMSNR, CNR, FOMCNR and ESAK of 3.4, 22.3, 386.4, 23.6, 433.7 and 1.28 mGy, respectively. Copper (90.3% purity) and titanium (95.0% purity) filters reduced ESAK by an average of 60% without compromising diagnostic quality, while brass and nickel filters increased dose under the conditions of the study. Conclusions: Our findings show that optimizing lumbar spine projection can reduce radiation dose without compromising image quality. Low-cost copper and titanium filters can be valuable in resource-limited settings. Further research can explore additional strategies for radiological optimization.

Niveles de Referencia para Diagnóstico Locales en Procedimientos Radiográficos Dentales Periapicales. Primeros valores para Chile

RESUMEN: La información que aportan los procedimientos de radiología dental, tanto en la evaluación, como en el diagnóstico y tratamiento de patologías y/o alteraciones dento maxilofaciales, hace que correspondan al tipo más frecuente de estudio radiológico. Sin embargo, existe un escaso conocimiento en nuestro país respecto de los niveles de dosis que se imparten en dichos procedimientos, haciendo necesaria su determinación para maximizar el beneficio derivado de los mismos y minimizar el riesgo radiológico para los pacientes. El presente estudio determinó el nivel de referencia para diagnóstico (NRD) local en la radiografía periapical de Molar maxilar e Incisivo, para ello se realizaron simulaciones de los procedimientos radiográficos en un maniquí antropomorfo seccional y se determinó el valor de Kerma aire en la superficie de entrada con retrodispersión mediante dosimetría termoluminiscente. Los NRD locales determinados en la radiografía periapical de Molar maxilar fueron 5,6 mGy para adultos y 4,0 mGy para niños; mientras que en la radiografía periapical de Incisivo fue de 9,2 mGy para pacientes adultos y 1,8 mGy para niños. Los resultados obtenidos buscan orientar la ejecución de futuras investigaciones en el área y aportar información del nivel de radiación en estos procedimientos, con lo que se espera promover una cultura de radioprotección y motivar la optimización de las dosis registradas.

ABSTRACT: The information provided by dental radiology procedures, both in evaluation, as well as in the diagnosis and treatment of pathologies and / or dentomaxilofacial alterations, makes them the most frequent type of radiological study. However, there is a meager knowledge in our country regarding dose levels applied in such procedures, making their determination necessary to maximize the benefits and to minimize the radiological risk to patients. The present study determined the local diagnostic reference level (LDRL) for the periapical radiography of the Maxillary molar and Incisive. Simulations of radiographic procedures were performed and the value of air Kerma at the entrance surface with backscattering, was estimated using thermo luminescent dosimetry. The LDRL determined in the maxillary molar periapical radiography was 5.6 mGy for adults and 4.0 mGy for children; while on the incisive periapical radiography it was 9.2 mGy for adult patients and 1.8 mGy for children. The results obtained seek to guide the execution of future research in the area and provide information on the radiation doses delivered in these procedures, which is expected to promote a radiation protection culture and motivate the optimization of the registered doses.

Niveles de Referencia para Diagnóstico en Procedimientos Radiológicos Dentales: Una Guía Práctica / Diagnostic Reference Levels in Dental Radiological Procedures: A Practical Guide

RESUMEN: Las exposiciones médicas con radiación ionizante son actualmente la principal fuente de exposición a la radiación artificial a nivel global, entre ellas, los exámenes dentales corresponden a uno de los más frecuentes. Para prevenir dosis innecesariamente altas a los pacientes durante estas exposiciones, la Comisión Internacional de Protección Radiológica (ICRP) recomienda la utilización de Niveles de Referencia para Diagnóstico (DRLs), como una herramienta efectiva de ayuda a la optimización de la protección radiológica en la exposición médica de pacientes. Dado que la legislación de Chile aún no ha incorporado el uso de los DRLs, el presente trabajo de revisión tuvo como objetivo analizar la publicación N° 135 de la ICRP para generar un documento que sirva de guía para los odontólogos, explicando de manera didáctica y en un lenguaje sencillo, pero técnico, los principales aspectos a tener en cuenta para establecer los DRLs en procedimientos de radiología dental.

SUMMARY: Currently exposure to ionizing radiation is currently the main source of exposure to artificial radiation worldwide, with dental examinations being one of the most frequent events. In order to prevent exposure of unnecessarily high doses in patients, the International Commission on Radiological Protection (ICRP) recommends the use of Diagnostic Reference Levels (DRLs), as an effective tool to help maximize protection from radiation during medical exposure of patients. Given that the Chilean legislation has not yet incorporated the use of DRLs, the purpose of this study was to analyze publication N° 135 of the ICRP to generate a document, to serve as a guide for dentists, didactically outlining in simple but technical language, the main aspects to consider when establishing DRLs in dental radiology procedures.

Willingness to pay for morbidity and mortality risk reductions during an epidemic. Theory and preliminary evidence from COVID-19.

The COVID-19 pandemic and the strong social distancing measures adopted by governments around the world provide an ideal scenario to evaluate the trade-off between lives saved and morbidity avoided on the one hand and reduced economic resources on the other. We adapt the standard model of willingness to pay (WTP) for mortality/morbidity risk reductions by incorporating a number of aspects that are highly relevant during an epidemic; namely, health-care capacity constraints, dynamic aspects of prevention (i.e., interventions aimed at flattening the epidemic curve), and distributional issues due to high heterogeneity in the underlying risks. The calibration of the model generates a WTP of the order of 24% of GDP. We conclude that the benefits in terms of lives saved and morbidity avoided can well justify the enormous economic costs generated by social distancing interventions. There is, however, significant that heterogeneity in WTP estimates depending on the degree of vulnerability to infection risk (e.g., by age), implying a large redistribution of income and well-being.

Lipid droplets are both highly oxidized and Plin2-covered in hepatocytes of diet-induced obese mice.

Chronic high-fat diet feeding is associated with obesity and accumulation of fat in the liver, leading to the development of insulin resistance and nonalcoholic fatty liver disease. This condition is characterized by the presence of a high number of intrahepatic lipid droplets (LDs), with changes in the perilipin pattern covering them. This work aimed to describe the distribution of perilipin (Plin) 2, an LD-associated protein involved in neutral lipid storage, and Plin5, which favors lipid oxidation in LD, and to evaluate lipid peroxidation through live-cell visualization using the lipophilic fluorescent probe C11-BODIPY581/591 in fresh hepatocytes isolated from mice fed a high-fat diet (HFD). Male C57BL/6J adult mice were divided into control and HFD groups and fed with a control diet (10% fat, 20% protein, and 70% carbohydrates) or an HFD (60% fat, 20% protein, and 20% carbohydrates) for 8 weeks. The animals fed the HFD showed a significant increase of Plin2 in LD of hepatocytes. LD from HFD-fed mice have a stronger lipid peroxidation level than control hepatocytes. These data provide evidence that obesity status is accompanied by a higher degree of lipid peroxidation in hepatocytes, both in the cytoplasm and in the fats stored inside the LD. Novelty Our study shows that lipid droplets from isolated hepatocytes in HFD-fed mice have a stronger lipid peroxidation level than control hepatocytes. C11-BODIPY581/591 is a useful tool to measure the initial level of intracellular lipid peroxidation in single isolated hepatocytes. Perilipins pattern changes with HFD feeding, showing an increase of Plin2 covering lipid droplets.

Composition and biological effects of goldenberry byproducts: an overview.

Goldenberry is a wild fruit that has been widely used for centuries, mainly in folk medicine. Most studies of goldenberry have focused on the fruit, but new research has studied its byproducts, which were considered to be waste until recently. The main objective of our study was to systematize the published information regarding the composition of goldenberry byproducts (calyces, leaves, seeds, and pomace) and their effects on biological systems. Goldenberry byproducts contain minerals, amino acids, withanolides, flavonoids, and essential fatty acids, thus representing good sources of these compounds. Some of their major biological effects include anti-inflammatory, antioxidant, antidiabetic, and antiproliferative effects. Information regarding their toxicity is also presented here. To determine the optimal dosage, further safety studies would be recommended to ensure the best health benefits of these compounds. The available evidence has demonstrated the nutritional value of different byproducts of goldenberry, suggesting them to be potential candidates for use in the cosmetic industry, in the preparation of functional foods, and in phytomedicine for the prevention and adjuvant treatment of some diseases. © 2020 Society of Chemical Industry.

Physalis peruviana L. Pulp Prevents Liver Inflammation and Insulin Resistance in Skeletal Muscles of Diet-Induced Obese Mice.

A chronic high-fat diet (HFD) produces obesity, leading to pathological consequences in the liver and skeletal muscle. The fat in the liver leads to accumulation of a large number of intrahepatic lipid droplets (LD), which are susceptible to oxidation. Obesity also affects skeletal muscle, increasing LD and producing insulin signaling impairment. Physalis peruviana L. (PP) (Solanaceae) is rich in peruvioses and has high antioxidant activity. We assessed the ability of PP to enhance insulin-dependent glucose uptake in skeletal muscle and the capacity to prevent both inflammation and lipoperoxidation in the liver of diet-induced obese mice. Male C57BL/6J mice were divided into groups and fed for eight weeks: control diet (C; 10% fat, 20% protein, 70% carbohydrates); C + PP (300 mg/kg/day); HFD (60% fat, 20% protein, 20% carbohydrates); and HFD + PP. Results suggest that PP reduces the intracellular lipoperoxidation level and the size of LD in both isolated hepatocytes and skeletal muscle fibers. PP also promotes insulin-dependent skeletal muscle glucose uptake. In conclusion, daily consumption of 300 mg/kg of fresh pulp of PP could be a novel strategy to prevent the hepatic lipoperoxidation and insulin resistance induced by obesity.

Effects of Infrared-Assisted Refractance Window™ Drying on the Drying Kinetics, Microstructure, and Color of Physalis Fruit Purée.

The objective of this work was to study the influence of the drying temperature, infrared (IR) radiation assistance, and the Mylar™ film thickness during Physalis fruit purée drying by the Refractance Window™ (RW™) method. For this, a RW™ dryer layout with a regulated bath at working temperatures of 60, 75, and 90 °C, Mylar™ thicknesses of 0.19, 0.25, 0.30 mm and IR radiation of 250 W for assisting RW™ drying process was used. Experimental curves data were expressed in moisture ratio (MR) in order to obtain moisture effective diffusivities (non-assisted RW™: Deff = 2.7-10.1 × 10-10 m2/s and IR-assisted RW™: Deff = 4.2-13.4 × 10-10 m2/s) and further drying curves modeling (Page, Henderson-Pabis, Modified Henderson-Pabis, Two-Term, and Midilli-Kucuk models). The Midilli-Kucuk model obtained the best-fit quality on experimental curves regarding statistical tests applied (Coefficient of Determination (R2), Chi-Square (χ2) and Root Mean Square Error (RMSE). Microscopical observations were carried out to study the RW™ drying conditions effect on microstructural changes of Physalis fruit purée. The main findings of this work indicated that the use of IR-assisted RW™ drying effectively accelerates the drying process, which achieved a decrease drying time around 60%. Thus, this combined RW™ process is strongly influenced by the working temperature and IR-power applied, and slightly by Mylar™ thickness.

Seguridad y Protección Radiológica en Procedimientos Imagenológicos Dentales / Safety and Radiological Protection in Dental Imaging Procedures

RESUMEN: Los procedimientos de imagenología dental son el tipo más frecuente de estudio radiológico y aportan información esencial para apoyar la evaluación, diagnóstico y tratamiento de patologías y/o alteraciones dentomaxilofaciales. La presente revisión narrativa, muestra los procedimientos de radiología dental, define conceptos asociados a la protección radiológica en éstos y entrega una guía con recomendaciones para mejorar la seguridad y protección radiológica del paciente y del operador, en esta clase de procedimientos imagenológicos. Comprender que bajo el actual sistema de protección radiológica, es el Odontólogo quién debe justificar la realización o no de un tipo de procedimiento radiológico, teniendo presente los costos económicos y sobre todo los costos en términos de dosis para el paciente.

ABSTRACT: Dental imaging procedures are the most frequent type of radiological study and provide essential information to support the evaluation, diagnosis and treatment of pathologies and / or dentomaxillofacial alterations. The present narrative review shows dental radiology procedures, defines concepts associated with radiological protection in these and provides a guide with recommendations to improve the safety and radiological protection of the patient and the operator in this kind of imaging procedures. Understanding that under the current system of radiological protection, it is the dentist who must confirm the realization or not, of a type of radiological procedure, keeping in mind the financial costs, and above all, consequences to the patient in terms of dose used in the procedure.

Organ and effective doses from paediatric interventional cardiology procedures in Chile.

The aim of this study was to present the results of organ and effective doses for paediatric patients for different types of interventional cardiology procedures for age and weight groups, derived from a patient dosimetry pilot programme carried out in Chile, under the auspices of the International Atomic Energy Agency. Over seven years, a retrospective collection of demographic and patient dose data was obtained: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time, dose-area product (DAP) and cumulative dose at patient entrance reference point. Monte Carlo software was used to calculate organ and effective doses. 1506 procedures were divided into four age and seven weight groups. Organ doses (median values) for diagnostic and therapeutic procedures were: active bone marrow 0.90 and 0.64mGy; heart 1.99 and 1.46mGy; lungs 3.56 and 2.59mGy; thyroid 1.27 and 0.83; and breast (in the case of females) 1.78 and 1.36mGy. The ranges for effective doses (median values) and weight bands were 1.2-3.9mSv for diagnostic procedures and 1.0-2.5mSv for therapeutic procedures. The resulting conversion factors (median values) to estimate effective dose from DAP (in mSv/Gy.cm2) were: 1.70; 0.89; 0.58; and 0.40, for age groups of <1year, 1-<5years, 5-<10years and 10-<16years, respectively. The obtained set of dose values will enable comparisons with other imaging procedures (comparing the same age bands) for justification and optimization purposes.

Priority setting in health care: disentangling risk aversion from inequality aversion.

In this paper, we introduce a tractable social welfare function that is rich enough to disentangle attitudes towards risk in health outcomes from attitudes towards health inequalities across individuals. Given this preference specification, we evaluate how the introduction of uncertainty over the severity of illness and over the effectiveness of treatments affects the optimal allocation of healthcare resources. We show that the way in which uncertainty affects the optimal allocation within our proposed specification may differ sharply from that in the standard expected utility framework.

Protacción rediológica en cardiología intervencionista pediátrica: avances y desafíos para Chile / Radiation protection in pediatric interventional cardiology. current status and challenges in chile

El objetivo de este artículo es mostrar los principales resultados alcanzados en Chile durante los últimos 5 años en procedimientos de cardiología intervencionista (CI) pediátrica y discutir acciones futuras para mejorar la seguridad radiológica en esta práctica médica. Todos los sistemas de rayos X usados en procedimientos de CI pediátrica en Chile han sido caracterizados en términos de dosis y calidad de imagen. En conjunto con esto, se han medido las tasas de dosis de radiación dispersa a la posición de los ojos y tobillos de los médicos cardiólogos. En mayo de 2010, se celebró en Santiago de Chile, un taller organizado por la Agencia Internacional de Energía Atómica (IAEA) que fue el punto de partida para un programa piloto sobre dosimetría de pacientes y personal médico para América Latina y el Caribe, con participantes de 11 países. En forma paralela, se realizó un curso piloto de formación en Protección Radiológica. Los primeros valores de dosis a pacientes pediátricos reportados en el marco del programa piloto realizado por la IAEA en América Latina y el Caribe, incluyó 70 procedimientos de Chile que posteriormente, fueron ampliados a una muestra de 544 procedimientos. Para mantener y mejorar las prácticas aprendidas, pensamos que el primer y fundamental paso que se podría dar en Chile, sería revisar y actualizar la legislación que regula el uso de radiaciones ionizantes, donde se incorpore la implementación de programas de Garantía de Calidad y una formación en Protección Radiológica diferenciada de acuerdo a las necesidades del personal médico.

Further actions to improve radiation safety in this medical practice are discussed. All the X-ray systems used in paediatric IC procedures in Chile have been characterized in terms of dose and image quality. In addition, dose rates of scattered radiation to the position of the eyes and ankles of cardiologists have been measured. In May 2010, in Santiago , Chile, a workshop organized by the International Atomic Energy Agency (IAEA) was the starting point for a pilot program on patient dosimetry and medical personnel for Latin America and the Caribbean, with participants from 11 countries. A pilot training course on Radiological Protection was given as part of the program. The first dose values reported for paediatric patients under the pilot program conducted by the IAEA in Latin America and the Caribbean included 70 procedures in Chile later extending to a total of 544 procedures. We think that a fundamental first step to improve IC radiation safety in Chile, would be to revise and update legislation on the use of ionizing radiation, including the implementation of quality assurance programs and training in radiation rrotection according to those involved in IC procedures.

Healthy life expectancy for selected race and gender subgroups: the case of Tennessee.

OBJECTIVE: To analyze healthy life expectancy (HLE) for major racial and gender subgroups, based on the diverse population of Tennessee and compared with the United States. MATERIALS AND METHODS: We use life table methodology and the HLE calculation model of the National Center for Health Statistics (NCHS), using two databases for 2001: NCHS National Vital Statistics Reports life tables and CDC Behavioral Risk Factor Surveillance System (BRFSS) survey. RESULTS: For Tennessee, although average total life expectancy (TLE) is 73.6 years at birth, only 61.1 years of "good" health are expected. Substantial racial and gender differences are found in both TLEs and HLEs with black males having the lowest and white females the highest. Although females have longer TLE, they spend more years in an unhealthy state than males. CONCLUSIONS: The findings raise new challenges for researchers and health policy makers for accomplishing the dual goals of longer life expectancy and elimination of health disparities among population subgroups.