Features of radiation protection equipment for the staff of X-ray operating rooms

This survey is devoted to the staff radiation protection in X-ray operating rooms. For self-safety staff must regularly and correctly use the protective equipment, which is ensured by their availability, convenience and manoeuvrability during procedures performing. The rapid development of interventional radiology led to the fact that the staff work in this area have one of the highest levels of occupational exposure. Unfortunately, domestic radiation protection system does not keep pace with such a rapid development of this branch of medicine. The article shows the basic principles of the distribution of scattered radiation in the X-ray operating room during the procedures performing. The distribution of scattered radiation around the patient for various modes of C-arm angiographic systems is shown. Graphical examples of scattered radiation distribution in X-ray operating rooms are given. Collective and individual protective equipment specifically designed for staff radiation protection in X-ray operating room are considered in detail. The common data on the protection features of the recommended staff protection equipment are presented. Most of the considered protection equipment is mandatory in many European countries, but not mentioned in domestic regulatory documents yet. The proposals for the modernization of the domestic radiation protection system for staff of X-ray operating rooms have been made. These recommendations focused on providing X-ray operating rooms with relevant radiation protection equipment, including eye protection, following the accumulated world experience and international regulations.

Collimation and Exposure Parameter Influence Image Quality and Potential Radiation Dose to the Eye Lens of Personnel in Computed Radiography of the Canine Pelvis

Introduction: The purpose of this study was to evaluate the effect of collimation on image quality and radiation dose to the eye lenses of the personnel involved in computed radiography of the canine pelvis.Materials and Methods: A retrospective study of canine pelvic radiographs (N = 54) was undertaken to evaluate the relationship between image quality and the degree of field the collimation used. This was followed by a prospective cadaver study (N = 18) that assessed the effects on image quality and on scattered radiation dose of different collimation field areas and exposure parameters. All radiographs were analyzed for image quality using a Visual Grading Analysis (VGA) with three observers. Finally, the potential scattered radiation dose to the eye lens of personnel restraining a dog for pelvic radiographs was measured.Results: The retrospective study showed a slightly better (statistically non-significant) VGA score for the radiographs with optimal collimation. Spatial and contrast resolution and image sharpness showed the greatest improvement in response to minimizing the collimation field. The prospective study showed slightly better VGA scores (improved image quality) with the optimal collimation. Increasing the exposure factors especially the tube current and exposure time (mAs) resulted in improved low contrast resolution and less noise in the radiographs. The potential eye lens radiation dose increased by 14, 28, and 40% [default exposures, increased the tube peak potential (kVp), increased mAs, respectively] as a result of reduced collimation (increased beam size).Conclusion: The degree of collimation has no statistically significant on image quality in canine pelvic radiology for the range of collimation used but does have an impact on potential radiation dose to personnel in the x-ray room. With regard to radiation safety, increases in kVp are associated with less potential scatter radiation exposure compared to comparable increases in mAs.

Development and evaluation of the effectiveness of educational material for radiological protection that uses augmented reality and virtual reality to visualize the behavior of scattered radiation

Understanding the behavior of scattered radiation is important for learning appropriate radiation protection methods, but many existing visualization systems for radiation require special devices, making it difficult to use them in education. The purpose of this study was to develop teaching material for radiation protection that can help visualize the scattered radiation with augmented and virtual reality on a web browser, develop a method for using it in education and examine its effectiveness. The distribution of radiation during radiography was calculated using Monte Carlo simulation, and teaching material was created. The material was used in a class for department of radiological technology students and its influence on motivation was evaluated using a questionnaire based on the evaluation model for teaching materials. In addition, text mining was used to evaluate impressions objectively. Educational material was developed that can be used in augmented and virtual reality for studying the behavior of scattered radiation. The results of the questionnaire showed that the average value of each item was more than 4 on a 5-point scale, indicating that the teaching material attracted the interest of users. Through text mining, it could be concluded that there was improved understanding of, and confidence in, radiation protection.

Characteristics of solar radiation at Xiaotang, in the northern marginal zone of the Taklimakan Desert

The characteristics of solar radiation and the influence of sand and dust on solar radiation in the northern margin of Taklimakan Desert were analyzed using radiation observation data from 2018. The results showed that the annual total radiation, direct radiation, and scattered radiation at Xiaotang were 5,781.8, 2,337.9, and 3,323.8 MJ m−2, respectively. The maximum monthly total radiation, direct radiation, and scattered radiation were observed in July (679.8 MJ m−2), August (317.3 MJ m−2), and May (455.7 MJ m−2), respectively. The aerosol optical depth corresponded well with the scattered radiation, and the maximum value was in May. Further analysis showed a significant correlation between the total radiation and solar height angle under different weather conditions. Under the same solar height angle, total radiation was higher during clear days but lower on sandstorm days. Calculation of atmospheric transmittance showed that the average atmospheric transmittance on a clear day was 0.67; on sand-and-dust days, it was 0.46. When the atmospheric transmittance was 0.5, the increase in scattering radiation by aerosol in the air began to decrease. Probability analysis of radiation indicated the following probabilities of total radiation <500 W m−2 occurring on clear, floating-dust, blowing-sand, and sandstorm days: 67.1%, 76.3%, 76.1%, and 91.8%, respectively. Dust had the greatest influence on direct radiation; the probabilities of direct radiation <200 W m−2occurring on clear, floating-dust, blowing-sand, and sandstorm days were 44.5%, 93.5%, 91.3%, and 100%, respectively, whereas those of scattered radiation <600 W m−2were 100%, 99.1%, 98.1%, and 100%, respectively. Therefore, the presence of dust in the air will reduce scattered radiation.

Can a Strong Radio Burst Escape the Magnetosphere of a Magnetar?

We examine the possibility that fast radio bursts (FRBs) are emitted inside the magnetosphere of a magnetar. On its way out, the radio wave must interact with a low-density e ± plasma in the outer magnetosphere at radii R = 109–1010 cm. In this region, the magnetospheric particles have a huge cross section for scattering the wave. As a result, the wave strongly interacts with the magnetosphere and compresses it, depositing the FRB energy into the compressed field and the scattered radiation. The scattered spectrum extends to the γ-ray band and triggers e ± avalanche, further boosting the opacity. These processes choke FRBs, disfavoring scenarios with a radio source confined at R ≪ 1010 cm. Observed FRBs can be emitted by magnetospheric flare ejecta transporting energy to large radii.

Mathematical modelling of optical radiation transport in biological tissues under the conditions of moveable integrating spheres registration

To describe the propagation of radiation in biological tissue, it is crucial to know the tissue’s optical characteristics. Integrating spheres method is widely used for experimental determination of optical properties of biological tissues. In this method, radiation scattered by the test sample in forward and backward directions is detected by the integrating spheres, along with the radiation that passed through the sample without scattering. In order to increase information content of the measurements, a moveable integrating spheres method was proposed, allowing one to register scattered radiation at different distances from sample surface to sphere ports. In this work, using the multilayer Monte Carlo method a numerical simulation of radiation propagation in a turbid medium was carried out under the conditions of detecting scattered radiation by moveable and stationary integrating spheres. Random errors were added to the direct problem solution in order to simulate experimental inaccuracies. The corresponding inverse problems were solved and the errors arising in the determination of optical properties (albedo, scattering anisotropy, optical depth) were compared in the cases of moveable and fixed spheres. It is shown that the same error in the inverse problem input data leads to smaller root-mean-square deviation from the true values when reconstructing albedo and anisotropy with the moveable spheres method, compared to the classical stationary spheres approach.