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Background.Anecdotal reports are appearing in the scientific literature about cases of brain tumors in interventional physicians who are exposed to ionizing radiation. In response to this alarm, several designs of leaded caps have been made commercially available. However, the results reported on their efficacy are discordant.Objective.To synthesize, by means of a systematic review of the literature, the capacity of decreasing radiation levels conferred by radiation attenuating devices (RADs) at the cerebral level of interventional physicians.Methodology.A systematic review was performed including the following databases: MEDLINE, SCOPUS, EBSCO, Science Direct, Cochrane Controlled Trials Register (CENTRAL), WOS, WHO International Clinical Trials Register, Scielo and Google Scholar, considering original studies that evaluated the efficacy of RAD in experimental or clinical contexts from January 1990 to May 2023. Data selection and extraction were performed in triplicate, with a fourth author resolving discrepancies.Results.Twenty articles were included in the review from a total of 373 studies initially selected from the databases. From these, twelve studies were performed under clinical conditions encompassing 3801 fluoroscopically guided procedures, ten studies were performed under experimental conditions with phantoms, with a total of 88 procedures, four studies were performed using numerical calculations with a total of 63 procedures. The attenuation and effectiveness of provided by the caps analyzed in the present review varying from 12.3% to 99.9%, and 4.9% to 91% respectively.Conclusion.RAD were found to potentially provide radiation protection, but a high heterogeneity in the shielding afforded was found. This indicates the need for local assessment of cap efficiency according to the practice.

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The main objective of this work was to propose and evaluate a methodology for shielding-gas selection in additive manufacturing assisted by wire arc additive manufacturing (WAAM) with an austenitic stainless steel as feedstock. To validate the proposed methodology, the impact of multi-component gases was valued using three different Ar-based blends recommended as shielding gas for GMA (gas metal arc) of the target material, using CMT (cold metal transfer) as the process version. This assessment considered features that potentially affect the building of the case study of thin walls, such as metal transfer regularity, deposition time, and geometrical and metallurgical characteristics. Different settings of wire-feed speeds were conceived to maintain a similar mean current (first constraint for comparison's sake) among the three gas blends. This approach implied different mean wire-feed speeds and simultaneously forced a change in the deposition speed to maintain the same amount of material deposited per unit of length (second comparison constraint). The composition of the gases affects the operational performance of the shielding gases. It was concluded that by following this methodology, shielding-gas selection decision-making is possible based on the perceived characteristics of the different commercial blends.

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The pursuit of development in an economically sustainable and ecologically sound manner is a goal of modern society. It has been investing in products that minimize their environmental impact, particularly concerning the use of plastic. This material is highly detrimental to nature due to its toxicity and long decomposition period. The present study aims to analyze the feasibility of producing blocks made of concrete with different amounts of waste plastic taken from coastal and estuarine areas. After laboratory analysis, it was found that blocks containing 5% plastic exhibit good compressive strength and are lighter. Additionally, there was an increase in the acidity of the sample, a decrease in the density of the block, and reductions in both flexural and compressive strength. The prototype, composed of 5% plastic by mass, proves to be efficient for constructing single-story houses. It meets the minimum requirements for normative resistance, effectively encapsulating the plastic within the block and thereby reducing its environmental impact.

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Radiometric surveys in radiotherapy bunkers have been carried out in Brazil for many years, both by the same radiotherapy facility for verification of shielding as by the regulatory agency for licensing and control purposes. In recent years, the Intensity Modulated Radiation Therapy (IMRT) technique has been gradually incorporated into many facilities. Therefore, it has been necessary to consider the increased leakage component that has an important impact on the secondary walls. For that, a radiometric survey method has been used that considers an increased 'time of beam-on' for the secondary walls. In this work we discuss two methods of doing this: the first considers that this 'time of beam-on' affects the sum of the two components, leakage and scattered. In another method it is considered that only the leakage component is affected by this extended 'time of beam-on'. We compare the methods and show that for secondary walls withU= 1 the first method overestimates dose rates by important percentages and for secondary walls withU< 1 it can both overestimate or underestimate the dose rates, depending on the parameters of the project. An optimized procedure is proposed, according to the use factor (U) of the secondary wall to be measured.

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Purpose.To show the considerations followed for MR-linac in shielding design for the first MR-linac in Mexico following the national clinical necessities.Method.The National Council on Radiation Protection and Measurements (NCRP) 151 recommendations were followed for the shielding design for primary and secondary barriers and the door design. The calculations were made considering the clinical demands in the country, that is, intensity modulated (IMRT) and 3D conformal radiotherapy (3DC-RT) in 80%-20% proportion.Results.The values obtained in the level survey fully comply with the limits established by the national regulatory authority and with those recommended by the International Commission on Radiological Protection (ICRP) for public and occupational exposures.Conclusion.It is remarkable that the workload may increase or that the doses per patient may increase considering occupancy factors, which would allow the introduction of hypofractionated techniques with the same number of patients considered in this work without the need to make modifications in the bunker design.

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Introducción: el diseño de los búnkeres de radioterapia es de vital importancia no solo por la seguridad radiológica, sino también por el costo que implican. Los cálculos de blindaje de las paredes primarias de los búnkeres de los aceleradores lineales de radioterapia se determinan a partir del factor de uso de estas paredes. Los documentos internacionales como el NCRP 151 utilizan para el cálculo de estas barreras un factor de uso igual a 0.25. Objetivo: estudiar la distribución del uso de las barreras primarias en función de los tratamientos realizados buscando contrastar la homogeneidad en el uso de las barreras. Material y Métodos: con los datos de pacientes realizados durante un año (2021) en dos aceleradores lineales, uno dual y otro monoenergético, se generó una base de datos con la que se calculó la frecuencia de uso de las paredes primarias. En el presente trabajo se evalúa la diferencia entre el uso dado de las barreras y las estimaciones de uso internacional. Resultados: se encuentra que en el acelerador dual en la energía de 15X los campos más usados tienen ángulos de gantry 0º, 90º, 180º, 270º, teniendo un peso acumulado aproximado al 65% al igual que la carga de trabajo para esos ángulos, esto implica que los ángulos diferentes a estos tienen un uso muy inferior al previsto por el cálculo inicial. En el acelerador dual en la energía de 6X el campo más usado es a 0º teniendo un peso aproximado al 14%, pero la carga de trabajo a 0º no se diferencia apreciablemente del resto de los ángulos ya que la distribución no tiene direcciones preferenciales, ninguno de los valores llega a 10% que concuerda con el uso homogéneo de la barrera. En el acelerador monoenergético el peso relativo de los ángulos de 90º y 270º en el uso de las barreras es aproximadamente 34% para cada una, superior al 25% estimado inicialmente. Conclusiones: las barreras primarias de los búnkeres de radioterapia tienen espesores marcados por el cálculo de blindaje, los cuales se pueden hacer basados en documentos internacionales que son referencia del tema. Se considera en las referencias para la barrera primaria un factor de uso igual para las mismas, sin embargo en la práctica clínica se pueden tener un factor de uso no uniforme respondiendo a los tipos de tratamientos que se designen realizar en el equipo. Esta realidad abre la puerta para plantear blindajes optimizados que podrían generar búnkeres más económicos y mejor utilización del espacio de acuerdo a las condiciones dadas para cada caso en particular.

Introduction: The design of radiotherapy bunkers is of vital importance not only for radiation safety, but also for the cost involved. The shielding calculations of the primary walls of radiotherapy linear accelerator bunkers are determined from the use factor of these walls. International documents such as NCRP 151 use for the calculation of these barriers a usage factor equal to 0.25. Objective: to study the distribution of the use of primary barriers according to the treatments performed, seeking to contrast the homogeneity in the use of the barriers. Material and Methods: with the data of patients performed during one year (2021) in two linear accelerators, one dual and the other monoenergetic, a database was generated with which the frequency of use of the primary walls was calculated. The present work evaluates the difference between the given use of the barriers and the estimates of international use. Results: it is found that in the dual accelerator at 15X energy the most used fields have gantry angles 0º, 90º, 180º, 270º, having an accumulated weight of approximately 65% as well as the workload for those angles, this implies that the angles different from these have a use much lower than the one foreseen by the initial calculation. In the dual accelerator at 6X energy the most used field is at 0º having an approximate weight of 14%, but the workload at 0º is not appreciably different from the rest of the angles since the distribution does not have preferential directions, none of the values reaches 10% which is consistent with the homogeneous use of the barrier. In the monoenergetic accelerator, the relative weight of the 90º and 270º angles in the use of the barriers is approximately 34% for each one, higher than the 25% initially estimated. Conclusions: the primary barriers of radiotherapy bunkers have thicknesses marked by the shielding calculation, which can be made based on international documents that are a reference on the subject. It is considered in the references for the primary barrier an equal use factor for them, however in clinical practice they can have a non-uniform use factor responding to the types of treatments that are designed to be performed in the equipment. This reality opens the door to propose optimized shielding that could generate more economical bunkers and better use of space according to the conditions given for each particular case.

Introdução: O projeto de bunkers de radioterapia é de vital importância não apenas para a segurança da radiação, mas também para o custo envolvido. Os cálculos de blindagem para as paredes primárias dos bunkers de aceleradores lineares de radioterapia são determinados com base no fator de uso dessas paredes. Documentos internacionais, como o NCRP 151, usam um fator de uso igual a 0,25 para o cálculo dessas barreiras. Objetivo: estudar a distribuição do uso de barreiras primárias de acordo com os tratamentos realizados, buscando contrastar a homogeneidade no uso das barreiras. Material e métodos: com os dados de pacientes tratados durante um ano (2021) em dois aceleradores lineares, um dual e outro monoenergético, foi gerado um banco de dados com o qual foi calculada a frequência de uso das paredes primárias. Este artigo avalia a diferença entre o uso determinado de barreiras e as estimativas internacionais de uso. Resultados: verifica-se que no acelerador duplo com energia de 15X os campos mais utilizados são os ângulos de pórtico 0º, 90º, 180º, 270º, com um peso acumulado de aproximadamente 65%, assim como a carga de trabalho para esses ângulos, o que implica que os ângulos diferentes desses têm um uso muito menor do que o previsto pelo cálculo inicial. No acelerador duplo a 6X de energia, o campo mais utilizado é o de 0º com um peso aproximado de 14%, mas a carga de trabalho em 0º não é sensivelmente diferente do resto dos ângulos, já que a distribuição não tem direções preferenciais, nenhum dos valores chega a 10%, o que é consistente com o uso homogêneo da barreira. No acelerador de monoenergia, o peso relativo dos ângulos de 90º e 270º no uso das barreiras é de aproximadamente 34% para cada um, superior aos 25% estimados inicialmente. Conclusões: as barreiras primárias dos bunkers de radioterapia têm espessuras balizadas pelo cálculo de blindagem, que pode ser feito com base em documentos internacionais que são referência no assunto. As referências para a barreira primária consideram um fator de uso igual para elas, mas na prática clínica elas podem ter um fator de uso não uniforme, dependendo do tipo de tratamento que o equipamento foi projetado para realizar. Essa realidade abre as portas para uma blindagem otimizada que poderia gerar bunkers mais econômicos e melhor uso do espaço de acordo com as condições dadas para cada caso específico.

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Este documento presenta una exhaustiva verificación de los sistemas de blindaje en un servicio de terapias radiometabólicas, ubicada en el cuarto piso del edificio de Medicina Nuclear. En esta área, se llevan a cabo terapias con I 131 , Lu177 y Ra223 al menos tres veces por semana, atendiendo a un promedio de 60 pacientes al mes, de los cuales aproximadamente 15 son tratados con terapias de baja actividad. Todo esto se realiza en estricto cumplimiento de los límites de dosis establecidos para la zona, los horarios de ocupación, los puntos de control y el equipo de medición correspondiente. La metodología propuesta está diseñada para abordar las necesidades prácticas de los centros de terapias radiometabólicas en su funcionamiento diario, considerando las condiciones reales de exposición. Los resultadosconfirman la idoneidad de los sistemas de blindaje, adaptados específicamente a las actividades desarrolladas en estas instalaciones

This document presents an exhaustive verification of shielding systems in a radiometabolic therapy service, located on the fourth floor of the Nuclear Medicine building. In this area, therapies with I 131, Lu177 and Ra223 are carried out at least three times a week, serving an average of 60 patients per month, of which approximately 15 are treated with low-activity therapies. All this is carried out in strict compliance with the dose limits established for the zone, the occupation times, the control points and the corresponding measurement equipment. The proposed methodology is designed to address the practical needs of radiometabolic therapy centers in their daily operation, considering real exposure conditions. The results confirm the suitability of the shielding systems, specifically adapted to the activities carried out in these installations

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The increase of revision surgeries in hip replacement procedure in Colombian young adult population can be addressed by a new design of femoral stem that reduces stress shielding. A new femoral stem was designed using topology optimization as a design aid to reduce the mass in the femoral stem and its overall stiffness, combined with the theoretical, computational, and experimental assessment of the new design that complies with a static and fatigue safety factor greater than one. The new femoral stem design can be used as a design tool to reduce the number of revision surgeries caused by stress shielding.

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The use of computational methods that allow us to perform characterization on new compounds is not a novelty; nevertheless, the degree of complexity of the structures makes their study more challenging since new techniques and methods are required to adjust to the new structural model. The case of nuclear magnetic resonance characterization of boronate esters is fascinating because of its widespread use in materials science. In this paper, we use density functional theory to characterize the structure of the compound 1-[5-(4,5-Dimethyl-1,3,2-dioxaborolan-2-yl)thiophen-2-yl]ethanonea by means of nuclear magnetic resonance. We studied the compound in its solid form with the PBE-GGA and PBEsol-GGA functionals, with a set of plane wave functions and an augmented wave projector, which included gauge in CASTEP and its molecular structure with the B3LYP functional using the package Gaussian 09. In addition, we performed the optimization and calculation of the chemical shifts and isotropic nuclear magnetic resonance shielding of 1H, 13C, and 11B. Finally, we analyzed and compared the theoretical results with experimental diffractometric data observing a good approximation.

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Biodegradable polymers have been strongly recognized as an alternative to replace traditional petrochemical plastics, which have become a global problem due to their long persistence in the environment. In this work, the effect of the addition of titanium dioxide nanoparticles (TiO2NP) on the morphology, physicochemical properties and biodegradation under industrial composting conditions of cassava starch-based nanocomposites obtained by extrusion at different screw speeds (80 and 120 rpm) were investigated. Films performed at 120 rpm (S120 and S120-TiO2NP) showed completely processed starch and homogeneously distributed nanoparticles, leading to much more flexible nanocomposites than those obtained at 80 rpm. The incorporation of TiO2NP led to an increase in storage modulus of all films and, in the case of S120-TiO2NP, to higher strain at break values. From the Kohlrausch-Williams-Watts theoretical model (KWW), an increase in the relaxation time of the nanocomposites was observed due to a decrease in the number of polymer chains involved in the relaxation process. Additionally, S120-TiO2NP showed effective protection against UV light, greater hydrophobicity and faster biodegradation in compost, resulting in a promising material for food packaging applications.

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Objective: The aim of this retrospective study was to assess bone resorption due to stress shielding in total knee replacement (TKR), comparing titanium bases (TiB) versus all polyethylene bases (APB), analyzing its incidence, progression and mechanical consequences after 10 years of follow-up. Methods: We evaluated two groups of patients undergoing TKR, one treated with TiB and the other with APB, operated consecutively between 2004 and 2009 with a diagnosis of idiopathic gonarthrosis and a minimum of 10 years of follow-up. Deen's radiographical method was used to assess tibial bone resorption. We assessed its incidence, progression, relationship with the femoro-tibial and prosthetic alignment, clinical outcomes and mechanical loosening. Results: Eighty-six patients were treated with TiB and 80 with APB with a median follow-up of 11 (range 10-15) years. The bone resorption rate in TiB was 24.41% and in APB was 1.25% (p < 0.0001). The type 2 of Deen's classification was the most frequently observed. Bone resorption was strongly correlated with preoperative varus femoro-tibial alignment and varus placement of the tibial component, also showing a significant association with postoperative femoro-tibial alignment correction (p 0.009). We observed no significant differences in functional scores or revision rates due to mechanical loosening after 10 years of follow-up between the groups. Conclusion: Titanium tibial bases in TKR showed a significantly higher incidence of medial tibia resorption compared to all-polyethylene bases. Our results suggest that bone resorption does not influence long-term mechanical loosening.

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Nylon 6/acrylonitrile-butadiene-styrene nanocomposites were prepared by mixing in a molten state and injection molded for application in electromagnetic interference shielding and antistatic packaging. Multi-wall carbon nanotubes (MWCNT) and maleic anhydride-grafted ABS compatibilizer were incorporated to improve the electrical conductivity and mechanical performance. The nanocomposites were characterized by oscillatory rheology, Izod impact strength, tensile strength, thermogravimetry, current-voltage measurements, shielding against electromagnetic interference, and scanning electron microscopy. The rheological behavior evidenced a severe increase in complex viscosity and storage modulus, which suggests an electrical percolation phenomenon. Adding 1 to 5 phr MWCNT into the nanocomposites produced electrical conductivities between 1.22 × 10-6 S/cm and 6.61 × 10-5 S/cm. The results make them suitable for antistatic purposes. The nanocomposite with 5 phr MWCNT showed the highest electromagnetic shielding efficiency, with a peak of -10.5 dB at 9 GHz and a value around -8.2 dB between 11 and 12 GHz. This was possibly due to the higher electrical conductivity of the 5 phr MWCNT composition. In addition, the developed nanocomposites, regardless of MWCNT content, showed tenacious behavior at room temperature. The results reveal the possibility for tailoring the properties of insulating materials for application in electrical and electromagnetic shielding. Additionally, the good mechanical and thermal properties further widen the application range.

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In this work, were determined some radiation shielding and dosimetric parameters of three types of bricks for photons energy from 1 keV to 100 GeV photons using the Phy-X/PSD software, and for comparison also has been calculated the same parameters for NBS concrete. The parameters calculated are the linear attenuation coefficients (LAC), effective atomic numbers (Zeff), half value layers (HVL), the energy absorption buildup factors (EABF) and the exposure buildup factors (EBF), as well as the coefficients to use the geometric progression (G-P) fitting method. Obtained results show that the three types of bricks can be used safely for the design of medical facilities housing mammography units (less than 30 keV).

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Introducción: la probabilidad de presentar una forma grave de COVID-19 es mayor en personas con algunas condiciones preexistentes. En la Argentina, las personas con alguna de estas comorbilidades realizaron un trabajo remoto y diferenciado respecto de sus compañeros. Esta estrategia se denomina shielding y tiene resultados heterogéneos, ya que ­si bien evita las infecciones­ puede tener algún impacto en las vivencias y salud de las personas. Métodos: investigación exploratoria a través de un diseño cualitativo basado en entrevistas semiestructuradas. Resultados: se realizaron 21 entrevistas. Se organizaron los conceptos en ejes temáticos de análisis. Como principales hallazgos se identificó que la salud general de las personas empeoró durante la pandemia a pesar de realizar trabajo diferenciado, y que durante el período explorado surgieron múltiples emergentes que incluyeron hábitos no saludables y estrategias positivas de afrontamiento. Respecto de lo laboral predominaron los sentimientos negativos. Conclusión: la implementación de shielding resulta insuficiente como única medida para la preservación de la salud de las personas con mayor riesgo de desarrollar formas graves de COVID-19. (AU)

Introduction: people with some pre-existing conditions are more likely to have a severe form of COVID-19. In Argentina, people with any of these comorbidities performed remote and differentiated work compared to their peers. This strategy is known as shielding and has heterogeneous results, since although it prevents infections it can have some impact on people's experiences and health. Methods: exploratory research through a qualitative design based on semi-structured interviews. Results: 21 interviews were conducted. The concepts were organized in thematic axes of analysis. As the main findings, we identified that the general health of the people worsened during the pandemic despite performing differentiated work, and that during the period explored, emerged both unhealthy habits and positive coping strategies. Regarding work, negative feelings predominated over positives. Conclusion: the implementation of shielding is insufficient as the only measure for the preservation of the health of people at higher risk of developing severe forms of COVID-19. (AU)

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Nonabsorbable suture augmentation of ligament reconstruction has seen an increase in use over the past several years with the goal of protecting the newly reconstructed ligament while allowing early rehabilitation for a potential earlier return to activity and sport. By spanning the joint with a durable nonabsorbable suture, this construct shares the stress and load seen by the reconstructed ligament, thereby protecting it from forces that could result in an early failure during the early ligamentization phase of the tendon graft. However, stress shielding of the ligament via nonabsorbable suture augmentation is also a double-edged sword, as a reduction in the stress and load seen by the ligament during this healing phase may ultimately have an impact on the final strength and composition of the reconstructed ligament. Although the long-term effects of this stress shielding have yet to be studied or reported in human subjects, multiple biomechanical and animal studies have demonstrated overall changes in architecture, tensile strength, and mechanical properties of a stress-shielded autograft ligament reconstruction.

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The maximum stresses on a femoral stem must be known for selecting the right size and shape of the shaft cross-sectional area for reducing the stress shielding effect generated after the total hip arthroplasty (THA) surgical procedure. The methodology proposed in this study provides the tools to the designers of femoral stems and orthopedic surgeons to select the adequate femoral stem cross section, decreasing the stiffness of the stem, thus reducing the stress shielding effect in the patient bones. The first contribution is the theoretical development of the maximum static stress calculation for 12 different femoral stem models with the beam theory, followed by the comparison with the static finite element analysis (FEA) simulations and finally the experimental corroboration of one femoral stem model measuring the strain with linear strain gages and transform it to stresses, the three different approaches provide comparable results, with a maximum average error of less than 8.5%. The second contribution is the formulation of a new selection methodology based on maximum stresses in the femoral stem and the cross section area for decreasing the stress shielding effect, optimizing the area needed for withstand the loads and decreasing the overall stiffens of the stem.

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This paper revises the use of polymer nanocomposites to attenuate high-energy electromagnetic radiation (HE-EMR), such as gamma radiation. As known, high-energy radiation produces drastic damage not only in facilities or electronic devices but also to life and the environment. Among the different approaches to attenuate the HE-EMR, we consider the use of compounds with a high atomic number (Z), such as lead, but as known, lead is toxic. Therefore, different works have considered low-toxicity post-transitional metal-based compounds, such as bismuth. Additionally, nanosized particles have shown higher performance to attenuate HE-EMR than those that are micro-sized. On the other hand, materials with π-conjugated systems can also play a role in spreading the energy of electrons ejected as a consequence of the interaction of HE-EMR with matter, preventing the ionization and bond scission of polymers. The different effects produced by the interactions of the matter with HE-EMR are revised. The increase of the shielding properties of lightweight, flexible, and versatile materials such as polymer-based materials can be a contribution for developing technologies to obtain more efficient materials for preventing the damage produced for the HE-EMR in different industries where it is found.

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Theoretical results for the magnetic shielding of protonated and unprotonated nitrogens of eumelanin building blocks including monomers, dimers, and tetramers in gas phase and water are presented. The magnetic property in water was determined by carrying out Monte Carlo statistical mechanics sampling combined with quantum mechanics calculations based on the gauge-including atomic orbitals approach. The results show that the environment polarization can have a marked effect on nitrogen magnetic shieldings, especially for the unprotonated nitrogens. Large contrasts of the oligomerization effect on magnetic shielding show a clear distinction between eumelanin building blocks in solution, which could be detected in nuclear magnetic resonance experiments. Calculations for a π-stacked structure defined by the dimer of a tetrameric building block indicate that unprotonated N atoms are significantly deshielded upon π stacking, whereas protonated N atoms are slightly shielded. The results stress the interest of NMR experiments for a better understanding of the eumelanin complex structure.

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BACKGROUND: Healthcare workers occupationally exposed to 18F-FDG cannot wear protective equipment, such as lead aprons, since the interaction between high energy radiation (511 keV) and metal increases the dose of radiation absorption. The objective of this study was to evaluate the shielding efficacy of a plastic polymer against the toxicogenomic effects of ionizing radiation in human lymphocytes, using cytokinesis-block micronucleus assays. METHODS: Human peripheral blood lymphocytes were isolated from three subjects and cultured under standard conditions. The cultures were exposed to 300 mCi of 18F-FDG at a distance of 10 cm for 10 min, in the absence of shielding or with lead, polymer, and lead + polymer shields. RESULTS: Lead shielding was found to increase the number of counts detected by Geiger-Müller radiation monitors as a consequence of the photoelectron effect. Conversely, the lead + polymer shield reduced the number of counts. The lead, polymer, and lead + polymer shields significantly reduced the frequency of micronuclei, nucleoplasmic bridges, and nuclear buds induced by ionizing radiation. Regarding cytotoxicity, only the lead + polymer shield re-established the cell cycle at the level observed for the negative control. CONCLUSIONS: Lead aprons that are internally coated with polymer increased the radiological protection of individuals occupationally exposed to 18F-FDG PET/CT, especially during examinations.

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Resumen: La protección gonadal ha sido durante largo tiempo un importante factor para abordar el requisito "tan bajo como sea razonablemente posible" ALARA. El presente artículo realiza una revisión sistemática sobre la utilidad de la protección gonadal en la radiografía de pelvis en la cual se han destacado los factores que tienen que ver con su realización diaria, es decir, la dosis de radiación involucrada, la radiosensibilidad de las gónadas, la posición del protector gonadal y el factor psicológico de la población en relación con su uso. La incorporación de equipamientos modernos, con dosis y protocolo optimizados, transforma el beneficio de la protección en un tema al menos debatible. Mientras algunos siguen respaldando la medida, otros organismos y autores ya no la respaldan. Es necesario reconsiderar prácticas actuales fundadas en consensos científicos que pueden estar obsoletos y considerar el factor de cambio cultural basados en estos nuevos consensos para su implementación, sin generar mayor preocupación en la población.

Abstract: Gonadal protection has long been an important factor in addressing the ALARA "as low as reasonably possible" requirement. This article performs a systematic review on the usefulness of gonadal protection in pelvic radiography, in which the factors that have to do with its daily performance have been highlighted, that is, radiation dose involved, the radiosensitivity of the gonads, the position of the gonadal shielding and the psychological factor of the population in relation to its use. The incorporation of modern equipment, with optimized dose and protocols, transforms the benefit of gonad shielding into an issue that is at least debatable. While some continue to support the measure, other agencies and authors no longer support it. It is necessary to reconsider current practices based on scientific consensus that may be obsolete and consider the factor of cultural change based on these new consensus for its implementation, without generating major concern in the population.

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