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OBJECTIVE: To assess the effectiveness of a quality control program in mammography services of the Brazilian National Health System (SUS). METHODS: A prospective study using temporal analysis of a health surveillance action was conducted. A total of 35 service providers that had mammography equipment in operation and regularly performed exams between 2007 and 2009 in the state of Goiás, Central-Western Brazil, participated in this study. Services were assessed during three site visits by performance testing of mammography equipment, film processors, and other materials, and image quality and entrance surface dose in a phantom were also assessed. Each service was scored according to the percentage of tests that conformed to standards. RESULTS: The mean percentage for compliance among the participating service providers were 64.1% (± 13.3%) in the first visit, 68.4% (± 15.9%) in the second, and 77.1% (± 13.3%) in the third (p < 0.001). The main improvements resulted from adjustments to the breast compression force, the automatic exposure control system, and the alignment of the compression paddle. The doses measured were within the conformity range in 80% of the services assessed. CONCLUSIONS: The implementation of this program in the mammography services was effective at improving the operational parameters of the mammography machines, although 40% of the services did not reach the acceptable level of 70%. This result indicates the need to continue this health surveillance action.

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OBJETIVO: Avaliar a efetividade de um programa de controle de qualidade de imagem nos serviços de mamografia da rede do Sistema Único de Saúde. MÉTODOS: Estudo prospectivo com análise temporal do tipo "antes e depois" de uma ação de vigilância em saúde. Participaram do estudo 35 serviços que tinham mamógrafos em operação e realizavam exames regularmente em Goiás entre 2007 e 2009. Foram avaliados os serviços, por testes de desempenho de mamógrafos, processadoras e demais materiais em três visitas técnicas, a qualidade da imagem e a dose de entrada no simulador radiográfico de mama. Cada serviço recebeu uma pontuação correspondente ao percentual dos testes em conformidade com os padrões. RESULTADOS: Os percentuais médios de conformidade dos serviços foram de 64,1% (± 13,3%) na primeira visita, 68,4% (± 15,9%) na segunda e 77,1% (± 13,3%) na terceira (p < 0,001). As principais melhorias foram decorrentes dos ajustes da força de compressão da mama, do controle automático de exposição e do alinhamento da bandeja de compressão. As doses medidas estavam dentro da faixa de conformidade em 80% dos serviços avaliados. CONCLUSÕES: A implantação do programa nos serviços foi efetiva para a melhoria dos parâmetros de operação do mamógrafo, embora 40% dos serviços não tenham alcançado o nível aceitável de 70%. Este resultado indica a necessidade de haver continuidade na vigilância em saúde.

OBJECTIVE: To assess the effectiveness of a quality control program in mammography services of the Brazilian National Health System (SUS). METHODS: A prospective study using temporal analysis of a health surveillance action was conducted. A total of 35 service providers that had mammography equipment in operation and regularly performed exams between 2007 and 2009 in the state of Goiás, Central-Western Brazil, participated in this study. Services were assessed during three site visits by performance testing of mammography equipment, film processors, and other materials, and image quality and entrance surface dose in a phantom were also assessed. Each service was scored according to the percentage of tests that conformed to standards. RESULTS: The mean percentage for compliance among the participating service providers were 64.1% (± 13.3%) in the first visit, 68.4% (± 15.9%) in the second, and 77.1% (± 13.3%) in the third (p < 0.001). The main improvements resulted from adjustments to the breast compression force, the automatic exposure control system, and the alignment of the compression paddle. The doses measured were within the conformity range in 80% of the services assessed. CONCLUSIONS: The implementation of this program in the mammography services was effective at improving the operational parameters of the mammography machines, although 40% of the services did not reach the acceptable level of 70%. This result indicates the need to continue this health surveillance action.

OBJETIVO: Evaluar la efectividad de un programa de control de calidad de imagen en los servicios de mamografía de la red del Sistema Único de Salud. MÉTODOS: Estudio prospectivo con análisis temporal de tipo "antes" y "después" de una acción de vigilancia en salud. Participaron del estudio 35 servicios que tenían mamógrafos operativos y que realizaban exámenes regularmente en el estado de Goiás, Brasil, entre 2007 y 2009. Se evaluaron los servicios, por pruebas de desempeño de mamógrafos , procesadoras y demás materiales en tres visitas técnicas, la calidad de la imagen y la dosis de entrada en el simulador radiográfico de mama. Cada servicio recibió una puntuación correspondiente al porcentaje de las pruebas en conformidad con los patrones. RESULTADOS: Los porcentajes promedio de conformidad de los servicios fueron de 64,1% (+/-13,3%) en la primera visita, 68,4% (+/-15,9%) en la segunda y 77,1% (+/-13,3%) en la tercera (p < 0,001). Las principales mejoras fueron decurrentes de los ajustes de la fuerza de compresión de la mama, del control automático de exposición y del alineamiento de la bandeja de compresión. Las dosis medidas estaban dentro del intervalo de conformidad en 80% de los servicios evaluados. CONCLUSIONES: La implantación del programa en los servicios fue efectiva para la mejora de los parámetros de operación del mamógrafo, a pesar de que 40% de los servicios no hayan alcanzado el nivel aceptable de 70%. Este resultado indica la necesidad de darle continuidad a la vigilancia en salud.

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Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental (14)C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3M NaOH solution. The trapped CO(2) was analyzed for (14)C by using a single stage accelerator mass spectrometry (SSAMS). All sampling sites revealed measurable (14)C excess values. The maximum excesses were of 15 and 14 mBq/m(3) for sampling sites placed at NE of the power plants, which is the main wind direction in the area. The mean excesses values were 12 mBq/m(3) to the NE direction, 8 mBq/m(3) to the E, 10 mBq/m(3) to the N, 8 mBq/m(3) to the WNW and 7 mBq/m(3) to the W direction (increasing distances from NE to W). Compared to other Light Water Reactors (LWR) data, these means' values are significantly higher than the average worldwide reported value of 3 mBq/m(3). Available data indicate that the observed values are not related to (14)C emission by the power plants vent stack. Other factors, such as topography, seem to have an important role because it affects wind dispersion thus favoring (14)C accumulation in the sampled area. Moreover, the high elevations around the power plants enhance the chances to measure high values of (14)C since the plume can be intercepted before it is drawn to the ground. Modeling of the plume has shown that its dispersion does not follow a Gaussian model and that agreement between atmospheric CO(2) and vegetation (14)C activities occurs only for sampling sites placed at NE of the power plants.

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Nuclear power plants release (14)C during routine operation mainly as airborne gaseous effluents. Because of the long half-life (5730 years) and biological importance of this radionuclide (it is incorporated in plant tissue by photosynthesis), several countries have monitoring programs in order to quantify and control these emissions. This paper compares the activity of (14)C in soils taken within 1km from a Brazilian nuclear power plant with soils taken within a reference area located 50km away from the reactor site. Analyses of total carbon, delta(13)C and (137)Cs were also performed in order to understand the local soil dynamics. Except for one of the profiles, the isotopic composition of soil organic carbon reflected the actual forest vegetation present in both areas. The (137)Cs data show that the soils from the base of hills are probably allocthonous. The (14)C measurements showed that there is no accumulation due to the operation of the nuclear facility, although excess (14)C was found in the litter taken in the area close to power plant. This indicates that the anthropogenic signal observed in the litter fall has not been transferred yet to the soil. This study is part of an extensive research programme in which other samples including air, vegetation and gaseous effluents (taken in the vent stack of the Brazilian nuclear power reactors Angra I and II) were also analyzed. The present paper aimed to evaluate how (14)C emissions from the nuclear power plant are transferred and stored by soils present in the surroundings of the reactor site. This is the first study concerning anthropogenic (14)C in soils in Brazil.

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OBJETIVO: Esta pesquisa visou a avaliar a qualidade dos serviços de mamografia do Distrito Federal e o impacto de uma intervenção de inspeção e capacitação. MATERIAIS E MÉTODOS: Foram estudados 41 serviços de mamografia no Distrito Federal no período de 2000 a 2002. A intervenção consistiu na inspeção inicial seguida de um treinamento e notificação oficial da Vigilância Sanitária. Os resultados de qualidade da imagem foram comparados "antes" e "depois" da intervenção. RESULTADOS: O estudo demonstrou que dos 36 serviços que completaram a pesquisa, nenhum estava acima de 90 por cento de conformidade antes da intervenção. Após a intervenção, dez unidades atingiram mais de 90 por cento. As principais melhorias foram em relação aos chassis, compressão da mama e visualização de microcalcificações. CONCLUSÃO: Apesar de o Distrito Federal dispor de muitos serviços, na sua maioria não eram de qualidade. A intervenção foi eficaz para a melhoria da qualidade, porém, torna-se necessária uma ação continuada para resolver os problemas restantes e aumentar o impacto.

OBJECTIVE: The present study was aimed at evaluating the quality and the impact of an intervention involving inspection and education in mammography centers of the Federal District, Brazil. MATERIALS AND METHODS: Forty one mammography centers in the Federal District were studied in the period between 2000 and 2002. The intervention involved an initial inspection followed by a training activity and notification of mammography centers by the Federal District Sanitary Vigilance authority. The imaging quality was compared before and after the intervention. RESULTS: None of the 36 centers which completed the study reached more than 90 percent compliance with the standard imaging quality prior to the interventions, whereas ten were above 90 percent afterwards. Major improvements were observed in chassis maintenance, breast compression and visualization of microcalcifications. CONCLUSION: Despite the availability of a great number of mammography centers in the Federal District, most of them did not meet the required quality standards. The intervention has shown to be effective for improving the imaging quality, however a continued action is required to solve the remaining problems and increase the impact of the program.

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(14)C specific activities were measured in grass samples collected around Brazilian nuclear power reactors. The specific activity values varied between 227 and 299 Bq/kg C. Except for two samples which showed (14)C specific activities 22% above background values, half of the samples showed background specific activities, and the other half had a (14)C excess of 1-18%. The highest specific activities were found close to the nuclear power plants and along the main wind directions (NE and NNE). The activity values were found to decrease with increasing distance from the reactors. The unexpectedly high (14)C excess values found in two samples were related to the local topography, which favors (14)C accumulation and limits the dispersion of the plume. The results indicate a clear (14)C anthropogenic signal within 5 km around the nuclear power plants which is most prominent along northeastwards, the prevailing wind direction.

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