Optimización de la protección en radiología y cardiología intervencionista pediatrica en América Latina y el Caribe (OPRIPALC) / Optimization of protection in pediatric interventional cardiology and radiology in Latin America and the Caribbean (OPRIPALC)

El objetivo del presente artículo ha sido describir el programa "Optimización de la Protección en Radiología Intervencionista Pediátrica en América Latina y el Caribe" (OPRIPALC) que nace el año 2018 como respuesta conjunta de la Organización Panamericana de la Salud y la Organización Mundial de la Salud, en cooperación con el Organismo Internacional de Energía Atómica, para colaborar con sus Estados miembros en asegurar que las exposiciones a la radiación de los pacientes pediátricos sean las mínimas necesarias durante los procedimientos intervencionistas. Actualmente, hay 18 centros de los siguientes 10 países que participan: Argentina, Brasil, Chile, Colombia, Costa Rica, Cuba, Ecuador, México, Perú y Uruguay. Para el desarrollo del programa se plantean una serie de objetivos, productos, actividades y resultados esperados. La puesta en marcha de la WEB de OPRIPALC ha significado un instrumento muy válido para seguir la información actualizada del programa. Un programa actualizado de formación en radioprotección para los profesionales implicados en el programa, se está realizando por medio de "webinars". Se deberá seguir actuando en la aplicación del programa de control de calidad básico para los equipos de rayos X participantes y validar los valores de los Niveles de Referencia para Diagnóstico (NRDs). Se propone formar un equipo de trabajo entre los Físicos Médicos y Tecnólogos Médicos participantes de OPRIPALC para implicarse en las pruebas de control básicas que todos los centros debieran realizar. Se han presentado algunos resultados iniciales de OPRIPALC en eventos científicos internacionales. Se está avanzando en proponer unos primeros valores sobre NRDs en procedimientos de intervencionismo cardiológico pediátrico por bandas de edad y peso. OPRIPALC es una de las pocas iniciativas de carácter regional para obtener valores de NRDs en procedimientos intervencionistas pediátricos. Se espera que tanto los valores de referencia como la metodología empleada en OPRIPALC, puedan ser utilizados en otras regiones del mundo.

The objective of this article has been to describe the program "Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean" (OPRIPALC) that was born in 2018 as a joint response of the Pan American Health Organization and the World Organization of the Health, in cooperation with the International Atomic Energy Agency, to collaborate with its member states in ensuring that radiation exposures of pediatric patients are the minimum necessary during interventional procedures. Currently, there are 18 centers from the following 10 countries participating: Argentina, Brazil, Chile, Colombia, Costa Rica, Cuba, Ecuador, Mexico, Peru and Uruguay. For the development of the program, a series of objectives, products, activities and expected results are proposed. The launch of the OPRIPALC WEBSITE has been a very valid instrument for following up-to-date information on the program. An updated training program in radiation protection for the professionals involved in the program is being carried out through webinars. It should continue acting in the application of the basic quality control program for the participating X-ray equipment and validate the values of the Diagnostic Reference Levels (DRLs). It is proposed to form a work team among the OPRIPALC participating medical physicists to get involved in the basic control tests that all centers should carry out. Some initial results of OPRIPALC have been presented at international scientific events. Progress is being made in proposing first values on DRLs in pediatric cardiac intervention procedures by age and weight bands. OPRIPALC is one of the few regional initiatives to obtain DRLs values in pediatric interventional procedures. It is expected that both the reference values and the methodology used in OPRIPALC can be used in other regions of the world.

Modulated volumetric arc therapy for total marrow irradiation: A feasibility study in the oncology hospital of CMN SXXI from a medical physics approach.

AIM: The objective of this study is to explore the use of volumetric arc therapy (VMAT) to perform total marrow irradiation (TMI) and compare its results to the standard TBI technique in the Mexican public health system. BACKGROUND: The standard total body irradiation (TBI) technique is used with chemotherapy as a method of a pre-transplant conditioning of the bone marrow. In this technique, the whole body of the patient is considered to be PTV and irradiated generating toxicities and raising concerns about possible development of radio-induced tumors. MATERIALS AND METHODS: Through the use of simulation tomography of 12 patients previously treated with TBI, twelve different treatment plans were created with the proposed TMI technique and compared with the conventional protocol, the treatment plans were evaluated with a dose volume histogram analysis and quality assurance was evaluated with a portal dosimetry system using the gamma index criteria 3%/3 mm. RESULTS: Experimental results show an increasing dose to 99% of PTV of up to 41.1% by using TMI with the VMAT technique. The mean average dose to PTV was increased up to 19.3%. The use of the new TMI technique caused an improvement in the mean average dose to 99% of the PTV as well the homogeneity of the dose distribution prescribed at the PTV while leading to a better reproducibility of the treatment. The Qa of all the plans met the criterion of gamma index 3 mm-3%. CONCLUSION: The results analysis shows that the proposed TMI technique is feasible and applicable in the Mexican public health system.

H*(10) due to scattered radiation on the cancer-patient bodies treated with Tomotherapy.

The ambient dose equivalent has been measured on the walls of a bunker with a 6 MV TomoLINAC, which was designed to have a conventional 18 MV LINAC. The ambient dose equivalent is due to scattered photons on patient bodies during cancer treatment. Measurements were carried out with thermoluminescent dosimeters that were fixed, at the isocentre plane, on the primary and secondary barriers, the maze, and on the TomoLINAC surface. Measurements were repeated three times, in each time dosimeters were on place during seven working days, where approximately 50 patients were treated per day. Ambient dose equivalent at each location was normalized to the total dose applied during the measuring time. The primary and secondary concrete barriers are thick enough to reduce the dose to safe values.

El grupo multifamiliar en el hospital de día de niños / Multi-family group at children's day hospital

En esta comunicación presentamos como se ha ido desarrollando y evolucionando el trabajo con las familias en la Unidad de Niños del HD-CET "Pradera de San Isidro", que consta de 20 plazas para niños entre 6 y 12 años.Desde la puesta en funcionamiento de este HD-CET en el 2002, partíamos con la premisa de que el trabajo con las familias era una parte esencial en el abordaje integral de la patología psiquiátrica grave en niños y adolescentes desde un HD. Durante los primeros años este trabajo incluía entrevistas familiares individuales con una frecuencia variable y un grupo de padres semanal, de hora y media de duración. En los casos de patología familiar grave se les orientaba hacia una terapia familiar o terapia individual de alguno de los padres fuera del HD-CET. Con los años tuvimos la ocasión de incluir en el programa terapéutico del HD-CET algunas terapias familiares, desde los modelos sistémico, psicoanalítico y de la mentalización. Hace dos años, nos decidimos a poner en marcha un grupo multifamiliar. Reflexionamos sobre las dinámicas y potencialidad terapéutica que este nuevo espacio está aportando al programa general del HD-CET

This communication presents how we have developed and the course our work has experienced with the families of the “Pradera de San Isidro” Day Hospital -Therapeutic and Educational Centre (DH - TEC) child unit. This unit attends 20 children between 6 and 12 years old. This DH-TEC was opened in 2002 and since the beginning it started with the premise that working with the families was an essential part of the DH integral approach with severe psychiatric pathology in children and adolescents. In the early years this work included family individual interviews with a variable frequency and a weekly parents group, that lasted an hour and a half. Those cases that presented severe family pathology were encouraged to receive family therapy or individual therapy for the parents but outside of the DH-TEC. Over the years, we had the chance to include in our program some family therapies from the psychoanalytic, systemic and mentalization models. Two years ago, we decided to start a multifamily group. We reflect on the dynamics and therapeutic potential that this new space is contributing to the general DH-TEC program

X-ray spectra and doses.

Using the Monte Carlo method the x-ray spectrum produced by 150keV electrons colliding with W, Rh and Mo targets were calculated. The x-ray spectra were calculated to 20, 50, and 100cm from the focal point. In order to analyze the effect of the filter, calculations were carried out with and without filter. The spectra were used to estimate the Kerma in air, the Ambient dose equivalent, and the Personal dose equivalent. The spectra were integrated in energy to obtain the total photon fluences. Calculated spectra depend on the type of target having the continuous spectrum due to bremsstrahlung and the characteristics x-rays. The Al filter eliminates the low-energy photons; however no effect is noticed when the photon energy is larger than 40keV. The largest effect of dose reduction due to the filter was noticed to 20cm for the Kerma in air.

Capacidades funcionales de adultos mayores en el asilo de ancianos San Pedro Claver del departamento de Managua, Nicaragua. marzo 2015

La presente investigación tiene como objetivo Comparar las capacidadesfuncionales de adultos mayores que viven institucionalizados (en asilo de anciano)y los que conviven en la comunidad.Se trata de un estudio transversal, descriptivo correlacional, cuantitativo, su unidadde análisis son los adultos mayores que conviven en escenarios diferentes loscuales fueron seleccionados por conveniencia. Las técnicas utilizadas fueron laentrevista, visita domiciliar, observación directa e indirecta. El instrumento utilizadofue la evaluación clínica del adulto mayor. Para el procesamiento de los datos seutilizó el programa estadístico SPSS 22, se analizaron los datos mediantedescriptivos de frecuencia simple, de contingencia, y pruebas de Rho deSpearman y Pearson con nivel de significancia estadística del 95%.Los principales resultados fueron: predominó el sexo masculino en asilo deancianos con 57.1% y en la comunidad el femenino con 71.4%, los rangos deedades para ambos fueron similares ubicadas entre 65 a más de 85 años, lamayor representación de procedencia en ambos fue de la ciudad de Managua, losniveles de escolaridad fueron primaria y secundaria. En relación a la condicionesde salud en ambos escenarios presentaron padecer de más de dos enfermedadescrónicas (89%), al igual de presentar dependencia funcional en las actividadesbásicas de la vida diaria e instrumentales (85%). Asimismo se encontraron nivelesaltos y moderados de riesgos de caídas (42.84%).Se concluyó que las dos poblaciones son significativamente similares, ambaspresentan capacidades funcionales limitadas y algunas personas alcanzan lacondición de discapacidad. Se recomienda a las autoridades pertinentes aplicareste tipo de evaluaciones para promover programas de intervención que seandirigidos tomando en cuenta las capacidades funcionales de los adultos mayoresde acuerdo a su contexto.

Detection of short-term chromosomal damage due to therapeutic 131I exposure in patients with thyroid cancer.

We evaluated the chromosomal aberration (CA) frequencies in the peripheral blood lymphocytes of ten female patients, age average 43.7 +/- 12.9, with thyroid cancer (TC) who had been exposed to 100-200 mCi therapeutic doses of 131I. The blood samples were obtained before-treatment and at 2 and 24 h after-treatment. Radiation was measured in the samples by means of dysprosium-activated calcium sulfate thermoluminescent dosimetry. The maximum radiation levels were detected in the samples taken 2 h after treatment. A positive correlation was found between the sample-emitted radiation values and the frequencies of CAs (r = 0.495; p < 0.01). The average baseline frequency of aberrations found in the ten studied patients was 0.009 per cell. Upon application of the 131I therapeutic dose, this frequency increased to 0.04 and 0.02 CAs/cell at 2 and 24 h after-treatment, respectively (p < 0.05). Break-type aberrations experienced a peak at 2 h after-treatment, whereas rejoined aberrations, such as dicentrics, rings, and radial figures, increased with sampling time. Seven patients with metastases had high amounts of CAs at 2 and 24 h after-treatment, in comparison to three patients without metastases who had a lower frequency of CAs at 24h aftertreatment. This difference could be due to the fact that circulating lymphocytes were exposed to a greater cancerous tissue mass, which retains 131I during the diagnostic and therapeutic processes. These results demonstrate the importance of detecting and surgically removing the largest possible amount of thyroid tissue in order to diminish the exposure of normal cells to radiation.