Avances y desafíos de la protección radiológica en cardiología intervencionista pediátrica para Chile entre los años 2013-2021 / Updating radiological protection for interventional procedures in pediatric cardiology in Chile

RESUMEN: En el año 2013, se publicó un artículo acerca de lo realizado en Chile en temas de protección radiológica en cardiología intervencionista (CI) pediátrica. A continuación se muestra el trabajo de continuidad realizado en los últimos 8 años, destacando los principales resultados alcanzados y proponiendo mejoras en la seguridad y protección radiológica en esta práctica clínica. Desde el año 2013 se han seguido evaluando en términos de dosis de radiación y calidad de imagen, los sistemas de rayos X utilizados en Chile para procedimientos de CI pediátricos y, en particular, los equipos de los servicios de los Hospitales Luis Calvo Mackenna y Roberto del Rio. Se han medido las tasas de dosis de radiación dispersa a la posición habitual de los ojos y tobillos de los cardiólogos que operan los equipos de rayos X. También contamos con un conjunto de "Niveles de Referencia para Diagnóstico" clasificados por rangos de edad y peso, junto con la estimación de valores de dosis por órgano y dosis efectiva para los pacientes. Podemos afirmar que, actualmente, contamos con una metodología consolidada para caracterizar, en términos de dosis y calidad de imagen, los sistemas de rayos X. Sin embargo, sigue pendiente actualizar la normativa nacional que regula el uso seguro de las radiaciones ionizantes en medicina, como también aspectos de formación en protección radiológica para el personal médico implicado.

ABSRSCT: An article on the status of radiological protection during procedures of interventional cardiology in pediatric patients in Chile was published in 2013. The present article relates the continuing efforts to improve radiological protection highlighting their results and proposing additional measures to improve radiological protection during the procedure. Since 2013 we have continued the evaluation of radiation doses, image quality, and X Ray systems used in Chile. We have measured diffused radiation dose at operator´s eye and ankle levels to elaborate a "Reference guide" according to patient´s age and weight. However, we still lack a national regulatory norm for the X Ray systems to be used and for the appropriate training of those involved in procedures of interventional cardiology in pediatric patients.

Perioperative Measurement of Radiation Exposure to Radiation-Sensitive Organs of Patients Undergoing Lumbar Surgeries Using a Thermoluminescent Dosimeter.

OBJECTIVE: To introduce a method of accurately measuring the equivalent dose received by radiation-sensitive organs using the thermoluminescent dosimeter (TLD) and to provide reference values for future studies associated with radiation protection in patients undergoing lumbar spine surgeries. METHODS: After careful selection and preparation, TLD chips were used to obtain measurements from the eyes, thyroid glands, breasts, and gonads of 20 patients undergoing lumbar spine surgeries. The results were obtained via air kerma conversion-related calculations. RESULTS: The overall radiation exposures absorbed perioperatively by the eyes, thyroid glands, right breasts, left breasts, right ovaries, left ovaries, and testes were 0.41 ± 0.13, 1.43 ± 0.45, 6.95 ± 3.63, 9.50 ± 6.14, 29.86 ± 28.62, 23.47 ± 22.10, and 5.41 ± 1.86 mSv, respectively. A single computed tomography (CT) scan contributed to more than 75% of the overall dose received regardless of the position used. CONCLUSIONS: Patients received significantly higher radiation doses from CT scans than from regular digital radiograph examinations. These radiation doses were concentrated in the regional area of scanning. Our results indicate the necessity and benefits of radiation protection measures, especially for the organs researched herein, when patients undergoing lumbar surgeries require radiographic diagnostic examinations.

[Automatic registration of patients in digital radiology facilities: dosimetric record]. / Sistemas de registro automático de pacientes en instalaciones de radiología digital. Historial dosimétrico.

There is a consensus in the international community regarding both the need for and benefits of systematic registration and planning of the dosage indicators in patients exposed to ionizing radiation. The main interest is in the registration and follow-up of the techniques and procedures that can involve the greatest risk from exposure to radiation. This register should be planned to include the structure and tools necessary to take the radiological safety of the patients into account, enabling the physicians requesting the studies to access the most important information in the register so they can appropriately justify the request for additional studies. Likewise, it should be considered a priority to establish diagnostic reference levels for the different magnitudes that are defined in function of the modality and techniques used; this information is useful for the staff involved in procedures that use ionizing radiation.

Estratégias para redução da exposição de radiação ionizante em mulheres submetidas à embolização de miomas uterinos / Strategies for reduction of exposure to ionizing radiation in women undergone to uterine fibroid embolization

OBJETIVO: quantificar a dose de radiação ionizante absorvida pelo ovário e pela pele em pacientes submetidas à embolização de miomas uterinos (EMUT), assim como sugerir um protocolo radiológico voltado à redução dos riscos envolvidos neste procedimento. MÉTODOS: setenta e três mulheres consecutivas (média etária de 27 anos), participantes de protocolo de pesquisa institucional, portadoras de miomas uterinos sintomáticos com indicação de tratamento minimamente invasivo, foram submetidas a procedimento de EMUT. Foram calculadas a estimativa de radiação absorvida pelos ovários por meio de dosímetros vaginais e a estimativa de dose de entrada na pele, por cálculos indiretos de absorção de radiação. As primeiras 49 pacientes fizeram parte do Grupo Pré-alteração e as últimas 24, do Grupo Pós-alteração. O segundo grupo recebeu um protocolo modificado de imagem radiológica, com redução pela metade do número de quadros por segundo durante as arteriografias, idealizado na tentativa de enquadrar os valores obtidos aos existentes na literatura, assim como foi evitado ao máximo a exposição desnecessária ao feixe de raios X. RESULTADOS: não houve complicações técnicas em nenhum dos procedimentos realizados. Não houve diferenças entre o tempo médio de fluoroscopia ou entre o número médio de arteriografias entre os dois grupos. Foi obtida uma redução de 57 por cento na estimativa de dose ovariana absorvida entre as pacientes dos dois grupos (29,0 versus 12,3 cGy), assim como uma redução de 30 por cento na estimativa de dose absorvida pela pele (403,6 versus 283,8 cGy). CONCLUSÕES: a redução significativa da absorção de radiação em pacientes submetidas a procedimentos de EMUT pode ser alcançada pela modificação do número de quadros por segundo nas aquisições arteriográficas, assim como pela implantação rotineira das normas de proteção radiológica.

PURPOSE: to determine the dose of ionizing radiation absorbed by the ovaries and the skin of patients undergoing uterine fibroid embolization (UFE), and to suggest a radiologic protocol directed at reducing the risks involved in this procedure. METHODS: seventy-three consecutive women (mean age: 27 years) participating in an institutional research protocol, having symptomatic uterine fibroids with indication for minimally invasive treatment, underwent UFE. We estimated the radiation absorbed by the ovaries by means of vaginal dosimeters and the radiation dose absorbed by the skin by means of indirect calculations of radiation absorption. The first 49 patients belonged to the Pre-modification Group, and the last 24, to the Post-modification Group. The second group received a modified protocol of X-ray imaging, with a reduction by half of the frames number per second during arteriography, in an attempt to match the values obtained to those of the literature, and avoiding as much as possible unnecessary exposure to the X-ray beam. RESULTS: there were no technical complications in any of the procedures performed. There were no differences in the mean fluoroscopy time or in the mean number of arteriographies between the two groups. We obtained a 57 percent reduction in the estimated absorbed ovarian dose between groups (29.0 versus 12.3 cGy) and a 30 percent reduction in the estimated dose absorbed by the skin (403.6 versus 283.8 cGy). CONCLUSIONS: a significant reduction in the absorption of radiation in patients undergoing UFE can be achieved by changing the number of frames per second in angiographic series, and by the routine use of radiological protection standards.