RESUMO
RESUMEN Durante los procedimientos intervencionistas que utilizan fluoroscopia, se entrega a los pacientes diferentes niveles de dosis de radiación, que pueden tener un impacto a corto, mediano o largo plazo, así como en su severidad. Esto en función del tipo de radiación utilizada y de la sensibilidad a la radiación del tipo(s) de órgano(s) irradiado, es en este punto que se vuelve determinante conocer la dosis a órganos entregada durante los procedimientos con el fin de asegurar el bienestar de los pacientes, este procedimiento no se puede realizar directamente en los órganos del paciente, por lo que se utilizan programas especializado en cálculos dosimétricos. El software PCXMC 2.0 logra estimar la dosis efectiva a través del método determinístico Monte Carlo, a su vez, agregando la dosis equivalente y evaluación de riesgo para estudios dosimétricos, por lo cual, el objetivo del presente trabajo fue proponer una metodología estandarizada para la utilización del programa PCXMC en el cálculo de estas dos magnitudes
ABSTRACT During interventional procedures that utilize fluoroscopy, patients are exposed to varying levels of radiation doses, which can have short, medium, or long term impacts, as well as varying severities. This depends on the type of radiation used and the radiation sensitivity of the organ(s) being irradiated. At this point, it becomes crucial to determine the organ doses delivered during procedures in order to ensure patient well-being. Since direct measurements cannot be made on the patient's organs, specialized software is used for dosimetric calculations. PCXMC 2.0 software achieves the estimation of effective dose through the deterministic Monte Carlo method, while also incorporating equivalent dose and risk assessment for dosimetric studies. Therefore, the objective of this work was to propose a standardized methodology for the use of the PCXMC 2.0 sofware in the calculation of these two magnitudes.it is important to outline a working method for this software and provide instructions on its operation
Assuntos
Doses de Radiação , Software , Fluoroscopia/métodos , Saúde Radiológica , Método de Monte Carlo , Relação Dose-Resposta à Radiação , Órgãos em Risco/efeitos da radiaçãoRESUMO
The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for pediatric interventional cardiology (IC) procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study was conducted in the framework of the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the program was focused on pediatric IC. Dose data from diagnostic and therapeutic procedures were collected between December 2020 and December 2021. Regional DRLs were set as the third quartile of patient dose data (kerma area product) collected in 18 hospitals from 10 countries in an initial sample of 968 procedures. DRLs were set for four age bands and five weight ranges. The values obtained for the four age bands (<1 yr, 1 to <5 yr, 5 to <10 yr and 10 to <16 yr) were 2.9, 6.1, 8.8 and 14.4 Gy cm2for diagnostic procedures, and 4.0, 5.0, 10.0 and 38.1 Gy cm2for therapeutic procedures, respectively. The values obtained for the five weight bands (<5 kg, 5 to <15 kg, 15 to <30 kg, 30 to <50 kg and 50 to <80 kg) were 3.0, 4.5, 8.1, 9.2 and 26.8 Gy cm2for diagnostic procedures and 3.7, 4,3, 7.3, 16.1 and 53.4 Gy cm2for therapeutic procedures, respectively. While initial data were collected manually as patient dose management systems (DMSs) were not available in most of the hospitals involved in the program, a centralized automatic DMS for the collection and management of patient dose indicators has now been introduced and is envisaged to increase the sample size. The possibility of alerting on high dose values and introducing corrective actions will help in optimization.
Assuntos
Cardiologia , Níveis de Referência de Diagnóstico , Cardiologia/métodos , Criança , Fluoroscopia , Humanos , América Latina , Doses de Radiação , Radiografia Intervencionista/métodos , Radiologia Intervencionista , Valores de ReferênciaRESUMO
Currently, chronic diarrhoea syndrome in children is a very common pathology whose aetiology is sometimes difficult to identify. Methodologies for the diagnosis of infections have diversified, and gas chromatography/mass spectrometry (GC/MS) is a very useful tool. The aim of this study was to identify volatile biomarkers of the presence of Giardia duodenalis in the faeces of patients with chronic diarrhoea (with and without giardiasis) using static headspace extraction followed by GC/MS. The analysis of the volatiles extracted from the headspace had enough sensitivity to detect differences in the volatile profiles in the faeces of the patients with and without Giardia duodenalis infection and discriminate between them. Dimethyl disulphide and trisulphide were found in the faeces of patients without giardiasis but not in the faeces of patients with G. duodenalis. Finally, three possible biomarkers, acetic acid, 1,4-dimethoxy-2,3-butanediol and 1,3-dimethoxy-2-propanol, were proposed to identify patients with giardiasis; these compounds were not present in the patients without the parasite. Multivariate analysis revealed that principal component 1 separated the stool samples according to the presence of infection by G. duodenalis despite the inter-individual variability in biological specimens such as faeces.
Assuntos
Diarreia/parasitologia , Giardia lamblia , Giardíase/diagnóstico , Animais , Biomarcadores/análise , Criança , Pré-Escolar , Fezes/parasitologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Giardíase/parasitologia , Humanos , Masculino , Análise MultivariadaRESUMO
The goal of the present study was to propose a set of national diagnostic reference levels (DRLs) in Costa Rica for paediatric interventional cardiology (IC) procedures classified by age and weight and to estimate the collective dose of the paediatric population from these intervention practices. The data collection period was May 2016 to May 2017. The third quartile of patient dose data distributions for kerma-area product (KAP) values was set as the national DRLs. A sample of 154 paediatric IC procedures (collected in the national paediatric hospital with a single x-ray system) was used and divided into four age ranges and five weight ranges. The national DRLs obtained for KAPs by age range were 1.79 Gy cm2 (<1 year) to 23.0 Gy cm2 (10-15 years). The national DRLs obtained for KAPs by weight range were 1.0 Gy cm2 (<10 kg) to 49.6 Gy cm2 (50-79 kg). The contribution to the collective dose of the population of Costa Rica amounted to 0.78 person Sv.
Assuntos
Radiografia Intervencionista/métodos , Adolescente , Criança , Pré-Escolar , Costa Rica , Humanos , Lactente , Recém-Nascido , Doses de Radiação , Valores de ReferênciaRESUMO
The volatile compositions of Charmat and traditional Chilean sparkling wines were studied for the first time. For this purpose, EG-Silicone and PDMS polymeric phases were compared and, afterwards, the most adequate was selected. The best extraction method turned out to be a sequential extraction in the headspace and by immersion using two PDMS twisters. A total of 130 compounds were determined. In traditional Chilean sparkling wines, ethyl esters were significantly higher, while acetic esters and ketones were predominant in the Charmat wines. PCA and LDA confirmed the differences in the volatile profiles between the production methods (traditional vs. Charmat).
Assuntos
Compostos Orgânicos Voláteis/análise , Vinho/análise , Chile , Ésteres/análise , Indústria Alimentícia , Cetonas/análiseRESUMO
The aim of this work was to analyse the radiation dose for patients and staff between X-ray systems, a new biplane with flat-panel detectors (FDs) and a conventional system equipped with image intensifier (II). Entrance surface air kerma (ESAK) and scatter doses were measured on polymethyl methacrylate (PMMA) phantoms of different thicknesses (from 4 to 16 cm). The ESAK values for the different acquisition modes and PMMA thicknesses were higher for the II in comparison with FDs. For the II, the scatter dose rates ranged from 0.67 to 12.2 mSv h(-1) at the eye position of the cardiologist during fluoroscopy and cine modes. At the lower extremities, these values were 1.11 and 24.24 mSv h(-1). In the case of the FDs, these values ranged from 0.24 to 0.67 mSv h(-1) for eye lens and from 0.73 to 2.01 mSv h(-1) for the position of cardiologist's ankle. The newly installed X-ray system showed an average reduction factor of up to 9.7 times for ESAK values. For the staff with an average reduction factor of 15.9 times at the eye position during fluoroscopy and cine modes, no protective tools are used. At the lower extremities, this value was 7.6 times.
Assuntos
Angiografia/instrumentação , Cardiologia/instrumentação , Radiologia Intervencionista/instrumentação , Ar , Angiografia/métodos , Cardiologia/métodos , Desenho de Equipamento , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Humanos , Pediatria/instrumentação , Pediatria/métodos , Imagens de Fantasmas , Polimetil Metacrilato/química , Doses de Radiação , Proteção Radiológica/métodos , Intensificação de Imagem Radiográfica/instrumentação , Radiologia Intervencionista/métodos , Espalhamento de Radiação , Raios XRESUMO
The aims of this work were to report the results of a national survey on entrance surface air kerma (ESAK) values for different phantom thicknesses and operation modes in paediatric interventional cardiology (IC) systems and to compare them with previous values. The national survey also offers suggested investigation levels (ILs) for ESAK in paediatric cardiac procedures. ESAK was measured on phantoms of 4-16 cm thickness of polymethyl methacrylate slabs. For low fluoroscopy mode (FM), ESAK rates ranged from 0.11 to 33.1 mGy min(-1) and for high FM from 0.34 to 61.0 mGy min(-1). For cine mode, values of ESAK per frame were from 1.9 to 78.2 µGy fr(-1). The ILs were suggested as the third quartile of the values measured. This research showed lower ESAK values than in previous research, particularly for ESAK values in cine modes. This work represents a first step towards launching a national programme in paediatric dosimetry for IC procedures.
Assuntos
Cardiologia/métodos , Pediatria/métodos , Radiologia Intervencionista/métodos , Ar , Cardiologia/instrumentação , Criança , Chile , Desenho de Equipamento , Fluoroscopia/métodos , Humanos , Pediatria/instrumentação , Imagens de Fantasmas , Polimetil Metacrilato , Doses de Radiação , Intensificação de Imagem Radiográfica/instrumentação , Radiologia Intervencionista/instrumentação , Radiometria/instrumentação , Raios XRESUMO
The aim of this study was to compare the performance of three digital X-ray systems [one flat-panel (DR) and two computed radiography (CR)] for chest radiography in terms of the entrance surface air kerma (ESAK) delivered to a polymethyl methacrylate phantom of 20 cm (equivalent to an adult patient) and image quality through of numerical evaluations using a test object (TO). The tube charge applied was ranged from 0.6 to 32 mAs, to a fixed tension of 125 kVp. The DR system presented the highest mean values of ESAK (615.9 µGy) along with the highest signal-to-noise ratio values, whereas CR systems showed a better high-contrast spatial resolution. Differences were statistically significant in both cases regarding the tube charge used. Thus, this parameter should be mainly considered to optimise the radiological protection through exposure settings selected. This survey represents the first effort to achieve optimisation in digital radiology for Chile.
Assuntos
Intensificação de Imagem Radiográfica/instrumentação , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/instrumentação , Radiografia Torácica/métodos , Adulto , Chile , Sistemas Computacionais , Humanos , Imagens de Fantasmas , Polimetil Metacrilato , Garantia da Qualidade dos Cuidados de Saúde , Proteção Radiológica/normas , Razão Sinal-Ruído , Software , Raios XRESUMO
INTRODUCCIÓN El Municipio de General Pueyrredón cuenta con un Comité de Vigilancia en Mortalidad Infantil, que se propone diagnosticar la problemática para orientar la gestión de futuras intervenciones. OBJETIVOS Caracterizar el perfil de la mortalidad infantil (MI) y sus componentes en el Partido de General Pueyrredón (PGP) durante el período 2010-2012. MÉTODOS Estudio transversal. Variables MI, edad, sexo, domicilio, causa de muerte y reducibilidad. Ámbito PGP. Población total de muertes en niños/as menores de un año con madres domiciliadas en dicho partido durante 2010-2012. Unidades de análisis áreas programáticas. Fuentes de datos secundarias. Construcción de base de datos unificada (municipalidad/provincia). Asignación de AP de pertenencia del evento de muerte. Agrupamiento de AP por zonas. Cálculo de tasas por zonas. Evaluación de significancia estadística mediante chi cuadrado. Resultados El análisis de la MI para el PGP mostró un predominio del componente posneonatal para los primeros dos años y del neonatal precoz en 2012. Los lugares de ocurrencia fueron hospitales públicos en aproximadamente un 70% de los casos. La estacionalidad de las defunciones fue variable, con enero, junio y octubre como los meses de mayores eventos. Se destacó una importante proporción de causas reducibles en todo el período, aunque con tendencia decreciente en el trienio; las causas reducibles por prevención, diagnóstico y tratamiento en el RN representaron la mayor proporción. En el análisis de la MI por AP, las más afectadas fueron las zonas Puerto, Oeste y Norte, con una marcada diferencia respecto a las áreas Centro y Noroeste. DISCUSIÓN Es necesario reforzar las acciones interdisciplinarias para el abordaje de la salud (en especial, del recién nacido), incorporar en los posneonatales las medidas de prevención de MI y trabajar sobre las grandes desigualdades existentes entre los distintos barrios del Partido.
Assuntos
Mortalidade Infantil , Causas de MorteRESUMO
The aim of this work was to investigate the differences in dose settings and image quality among 10 X-ray systems used for interventional cardiology in Chile. Entrance surface air kerma (ESAK) was measured on a phantom of 20 cm thickness of polymethyl methacrylate slabs. Image quality was evaluated using DICOM images of a test object Leeds TOR 18-FG for cine mode acquisition, through the numerical parameters signal-to-noise ratio (SNR), high-contrast spatial resolution (HCSR) and figure of merit. ESAK rate values for fluoroscopy modes ranged between 7.1 and 121.7 mGy min(-1). For cine mode, ESAK values per frame ranged from 63 to 400 µGy fr(-1). SNR and HCSR parameters for cine mode varied from 4.8 to 8.6 and 0.4 to 10, respectively. FOM values resulted from 6.9 to 64.5 among the different X-ray systems. Results show important differences between systems and point out the need to launch an optimisation programme.