Translating genetic findings to epigenetics: identifying the mechanisms associated with aging after high-radiation exposure on earth and in space.

Purpose: Exposure to radiation is a health concern within and beyond the Earth's atmosphere for aircrew and astronauts in their respective austere environments. The biological effects of radiation exposure from a multiomics standpoint are relatively unexplored and stand to shed light on tailored monitoring and treatment for those in these career fields. To establish a reference variable for genetic damage, biological age seems to be closely associated with the effect of radiation. Following a genetic-based study, this study explores the epigenetic landscape of radiation exposure along with its associative effects on aging processes. Methods: We imported the results of the genetics-based study that was a secondary analysis of five publicly available datasets (noted as Data1). The overlap of these genes with new data involving methylation data from two datasets (noted as Data2) following similar secondary analysis procedures is the basis of this study. We performed the standard statistical analysis on these datasets along with supervised and unsupervised learning to create preranked gene lists used for functional analysis in Ingenuity Pathway Analysis (IPA). Results: There were 664 genes of interest from Data1 and 577 genes from Data2. There were 40 statistically significant methylation probes within 500 base pairs of the gene's transcription start site and 10 probes within 100 base pairs, which are discussed in depth. IPA yielded 21 significant pathways involving metabolism, cellular development, cell death, and diseases. Compared to gold standards for gestational age, we observed relatively low error and standard deviation using newly identified biomarkers. Conclusion: We have identified 17 methylated genes that exhibited particular interest and potential in future studies. This study suggests that there are common trends in oxidative stress, cell development, and metabolism that indicate an association between aging processes and the effects of ionizing radiation exposure.

Influence of Body Mass Index on Radiation Exposure Across Imaging Modalities in the Evaluation of Chest Pain.

BACKGROUND: Essential to a patient-centered approach to imaging individuals with chest pain is knowledge of differences in radiation effective dose across imaging modalities. Body mass index (BMI) is an important and underappreciated predictor of effective dose. This study evaluated the impact of BMI on estimated radiation exposure across imaging modalities. METHODS AND RESULTS: This was a retrospective analysis of patients with concern for cardiac ischemia undergoing positron emission tomography (PET)/computed tomography (CT), cadmium zinc telluride single-photon emission CT (SPECT) myocardial perfusion imaging, or coronary CT angiography (CCTA) using state-of-the-art imaging modalities and optimal radiation-sparing protocols. Radiation exposure was calculated across BMI categories based on established cardiac imaging-specific conversion factors. Among 9046 patients (mean±SD age, 64.3±13.1 years; 55% men; mean±SD BMI, 30.6±6.9 kg/m2), 4787 were imaged with PET/CT, 3092 were imaged with SPECT/CT, and 1167 were imaged with CCTA. Median (interquartile range) radiation effective doses were 4.4 (3.9-4.9) mSv for PET/CT, 4.9 (4.0-6.3) mSv for SPECT/CT, and 6.9 (4.0-11.2) mSv for CCTA. Patients at a BMI <20 kg/m2 had similar radiation effective dose with all 3 imaging modalities, whereas those with BMI ≥20 kg/m2 had the lowest effective dose with PET/CT. Radiation effective dose and variability increased dramatically with CCTA as BMI increased, and was 10 times higher in patients with BMI >45 kg/m2 compared with <20 kg/m2 (median, 26.9 versus 2.6 mSv). After multivariable adjustment, PET/CT offered the lowest effective dose, followed by SPECT/CT, and then CCTA (P<0.001). CONCLUSIONS: Although median radiation exposure is modest across state-of-the-art PET/CT, SPECT/CT, and CCTA systems using optimal radiation-sparing protocols, there are significant variations across modalities based on BMI. These data are important for making patient-centered decisions for ischemic testing.

Lung ultrasound and procalcitonin, improving antibiotic management and avoiding radiation exposure in pediatric critical patients with bacterial pneumonia: a randomized clinical trial.

BACKGROUND: Pneumonia is a major public health problem with an impact on morbidity and mortality. Its management still represents a challenge. The aim was to determine whether a new diagnostic algorithm combining lung ultrasound (LUS) and procalcitonin (PCT) improved pneumonia management regarding antibiotic use, radiation exposure, and associated costs, in critically ill pediatric patients with suspected bacterial pneumonia (BP). METHODS: Randomized, blinded, comparative effectiveness clinical trial. Children < 18y with suspected BP admitted to the PICU from September 2017 to December 2019, were included. PCT was determined at admission. Patients were randomized into the experimental group (EG) and control group (CG) if LUS or chest X-ray (CXR) were done as the first image test, respectively. Patients were classified: 1.LUS/CXR not suggestive of BP and PCT < 1 ng/mL, no antibiotics were recommended; 2.LUS/CXR suggestive of BP, regardless of the PCT value, antibiotics were recommended; 3.LUS/CXR not suggestive of BP and PCT > 1 ng/mL, antibiotics were recommended. RESULTS: 194 children were enrolled, 113 (58.2%) females, median age of 134 (IQR 39-554) days. 96 randomized into EG and 98 into CG. 1. In 75/194 patients the image test was not suggestive of BP with PCT < 1 ng/ml; 29/52 in the EG and 11/23 in the CG did not receive antibiotics. 2. In 101 patients, the image was suggestive of BP; 34/34 in the EG and 57/67 in the CG received antibiotics. Statistically significant differences between groups were observed when PCT resulted < 1 ng/ml (p = 0.01). 3. In 18 patients the image test was not suggestive of BP but PCT resulted > 1 ng/ml, all of them received antibiotics. A total of 0.035 mSv radiation/patient was eluded. A reduction of 77% CXR/patient was observed. LUS did not significantly increase costs. CONCLUSIONS: Combination of LUS and PCT showed no risk of mistreating BP, avoided radiation and did not increase costs. The algorithm could be a reliable tool for improving pneumonia management. CLINICAL TRIAL REGISTRATION: NCT04217980.

Use of the flat panel detector fluoroscope reduces radiation exposure during periacetabular osteotomy.

The Periacetabular Osteotomy is a technically demanding procedure that requires precise intraoperative evaluation of pelvic anatomy. Fluoroscopic images pose a radiation risk to operating room staff, scrubbed personnel, and the patient. Most commonly, a Standard Fluoroscope with an Image Intensifier is used. Our institution recently implemented the novel Fluoroscope with a Flat Panel Detector. The purpose of this study was to compare radiation dosage and accuracy between the two fluoroscopes. A retrospective review of a consecutive series of patients who underwent Periacetabular Osteotomy for symptomatic hip dysplasia was completed. The total radiation exposure dose (mGy) was recorded and compared for each case from the standard fluoroscope (n = 27) and the flat panel detector (n = 26) cohorts. Lateral center edge angle was measured and compared intraoperatively and at the six-week postoperative visit. A total of 53 patients (96% female) with a mean age and BMI of 17.84 (± 6.84) years and 22.66 (± 4.49) kg/m2 (standard fluoroscope) and 18.23 (± 4.21) years and 21.99 (± 4.00) kg/m2 (flat panel detector) were included. The standard fluoroscope averaged total radiation exposure to be 410.61(± 193.02) mGy, while the flat panel detector averaged 91.12 (± 49.64) mGy (p < 0.0001). The average difference (bias) between intraoperative and 6-week postoperative lateral center edge angle measurement was 0.36° (limits of agreement: - 3.19 to 2.47°) for the standard fluoroscope and 0.27° (limits of agreement: - 2.05 to 2.59°) for the flat panel detector cohort. Use of fluoroscopy with flat panel detector technology decreased the total radiation dose exposure intraoperatively and produced an equivalent assessment of intraoperative lateral center edge angle. Decreasing radiation exposure to young patients is imperative to reduce the risk of future comorbidities.

If You Torture Your Data Long Enough, It Will Confess to Anything: On the Epidemiological Basis of the LNT Model.

This note deals with epidemiological data interpretation supporting the linear no-threshold model, as opposed to emerging evidence of adaptive response and hormesis from molecular biology in vitro and animal models. Particularly, the US-Japan Radiation Effects Research Foundation's lifespan study of atomic bomb survivors is scrutinized. We stress the years-long lag of the data processing after data gathering and evolving statistical models and methodologies across publications. The necessity of cautious interpretation of radiation epidemiology results is emphasized.

Replace the Linear No-threshold Model with a Risk-informed Targeted Approach to Radiation Protection.

ABSTRACT: The linear no-threshold (LNT) model may be useful as a simple basis for developing radiation protection regulations and standards, but it bears little resemblance to scientific reality and is probably overly conservative at low doses and low dose rates. This paper is an appeal for a broader view of radiation protection that involves more than just optimization of radiation dose. It is suggested that the LNT model should be replaced with a risk-informed, targeted approach to limitation of overall risks, which include radiation and other types of risks and accidents/incidents. The focus should be on protection of the individual. Limitation of overall risk does not necessarily always equate to minimization of individual or collective doses, but in some cases it might. Instead, risk assessment (hazards analysis) should be performed for each facility/and or specific job or operation (straightforward for specialized work such as radiography), and this should guide how limited resources are used to protect workers and the public. A graded approach could be used to prioritize the most significant risks and identify exposure scenarios that are unlikely or non-existent. The dose limits would then represent an acceptable level of risk, below which no further reduction in dose would be needed. Less resources should be spent on ALARA and tracking small individual and collective doses. Present dose limits are thought to be conservative and should suffice in general. Two exceptions are possibly the need for a lower (lifetime) dose limit for lens of the eye for astronauts and raising the public limit to 5 mSv y -1 from 1 mSv y -1 . This would harmonize the public limit with the current limit for the embryo fetus of the declared pregnant worker. Eight case studies are presented that emphasize how diverse and complex radiation risks can be, and in some cases, chemical and industrial risks outweigh radiation risks. More focus is needed on prevention of accidents and incidents involving a variety of types of risks. A targeted approach is needed, and commitments should be complied with until they are changed or exemptions are granted. No criticism of regulators or nuclear industry personnel is intended here. Protection of workers and the public is everyone's goal. The question is how best to accomplish that.

Protracted Exposure to a Sub-background Radiation Environment Negatively Impacts the Anhydrobiotic Recovery of Desiccated Yeast Sentinels.

ABSTRACT: Experiments that examine the impacts of subnatural background radiation exposure provide a unique approach to studying the biological effects of low-dose radiation. These experiments often need to be conducted in deep underground laboratories in order to filter surface-level cosmic radiation. This presents some logistical challenges in experimental design and necessitates a model organism with minimal maintenance. As such, desiccated yeast ( Saccharomyces cerevisiae ) is an ideal model system for these investigations. This study aimed to determine the impact of prolonged sub-background radiation exposure in anhydrobiotic (desiccated) yeast at SNOLAB in Sudbury, Ontario, Canada. Two yeast strains were used: a normal wild type and an isogenic recombinational repair-deficient rad51 knockout strain ( rad51 Δ). Desiccated yeast samples were stored in the normal background surface control laboratory (68.0 nGy h -1 ) and in the sub-background environment within SNOLAB (10.1 nGy h -1 ) for up to 48 wk. Post-rehydration survival, growth rate, and metabolic activity were assessed at multiple time points. Survival in the sub-background environment was significantly reduced by a factor of 1.39 and 2.67 in the wild type and rad51 ∆ strains, respectively. Post-rehydration metabolic activity measured via alamarBlue reduction remained unchanged in the wild type strain but was 26% lower in the sub-background rad51 ∆ strain. These results demonstrate that removing natural background radiation negatively impacts the survival and metabolism of desiccated yeast, highlighting the potential importance of natural radiation exposure in maintaining homeostasis of living organisms.

Science-informed Policy Making for Protecting People and the Environment from Radiation.

ABSTRACT: The process to arrive at the radiation protection practices of today to protect workers, patients, and the public, including sensitive populations, has been a long and deliberative one. This paper presents an overview of the US Environmental Protection Agency's (US EPA) responsibility in protecting human health and the environment from unnecessary exposure to radiation. The origins of this responsibility can be traced back to early efforts, a century ago, to protect workers from x rays and radium. The system of radiation protection we employ today is robust and informed by the latest scientific consensus. It has helped reduce or eliminate unnecessary exposures to workers, patients, and the public while enabling the safe and beneficial uses of radiation and radioactive material in diverse areas such as energy, medicine, research, and space exploration. Periodic reviews and analyses of research on health effects of radiation by scientific bodies such as the National Academy of Sciences, National Council on Radiation Protection and Measurements, United Nations Scientific Committee on the Effects of Atomic Radiation, and the International Commission on Radiological Protection continue to inform radiation protection practices while new scientific information is gathered. As a public health agency, US EPA is keenly interested in research findings that can better elucidate the effects of exposure to low doses and low dose rates of radiation as applicable to protection of diverse populations from various sources of exposure. Professional organizations such as the Health Physics Society can provide radiation protection practitioners with continuing education programs on the state of the science and describe the key underpinnings of the system of radiological protection. Such efforts will help equip and prepare radiation protection professionals to more effectively communicate radiation health information with their stakeholders.

A Revised System of Radiological Protection Is Needed.

ABSTRACT: The system of radiological protection has been based on linear no-threshold theory and related dose-response models for health detriment (in part related to cancer induction) by ionizing radiation exposure for almost 70 y. The indicated system unintentionally promotes radiation phobia, which has harmed many in relationship to the Fukushima nuclear accident evacuations and led to some abortions following the Chernobyl nuclear accident. Linear no-threshold model users (mainly epidemiologists) imply that they can reliably assess the cancer excess relative risk (likely none) associated with tens or hundreds of nanogray (nGy) radiation doses to an organ (e.g., bone marrow); for 1,000 nGy, the excess relative risk is 1,000 times larger than that for 1 nGy. They are currently permitted this unscientific view (ignoring evolution-related natural defenses) because of the misinforming procedures used in data analyses of which many radiation experts are not aware. One such procedure is the intentional and unscientific vanishing of the excess relative risk uncertainty as radiation dose decreases toward assigned dose zero (for natural background radiation exposure). The main focus of this forum article is on correcting the serious error of discarding risk uncertainty and the impact of the correction. The result is that the last defense of the current system of radiological protection relying on linear no-threshold theory (i.e., epidemiologic studies implied findings of harm from very low doses) goes away. A revised system is therefore needed.

Factors Influencing Effects of Low-dose Radiation Exposure.

ABSTRACT: It is now well accepted that the mechanisms induced by low-dose exposures to ionizing radiation (LDR) are different from those occurring after high-dose exposures. However, the downstream effects of these mechanisms are unclear as are the quantitative relationships between exposure, effect, harm, and risk. In this paper, we will discuss the mechanisms known to be important with an overall emphasis on how so-called "non-targeted effects" (NTE) communicate and coordinate responses to LDR. Targeted deposition of ionizing radiation energy in cells causing DNA damage is still regarded as the dominant trigger leading to all downstream events whether targeted or non-targeted. We regard this as an over-simplification dating back to formal target theory. It ignores that last 100 y of biological research into stress responses and signaling mechanisms in organisms exposed to toxic substances, including ionizing radiation. We will provide evidence for situations where energy deposition in cellular targets alone cannot be plausible as a mechanism for LDR effects. An example is where the energy deposition takes place in an organism not receiving the radiation dose. We will also discuss how effects after LDR depend more on dose rate and radiation quality rather than actual dose, which appears rather irrelevant. Finally, we will use recent evidence from studies of cataract and melanoma induction to suggest that after LDR, post-translational effects, such as protein misfolding or defects in energy metabolism or mitochondrial function, may dominate the etiology and progression of the disease. A focus on such novel pathways may open the way to successful prophylaxis and development of new biomarkers for better risk assessment after low dose exposures.

Evaluation of Radiation Exposure and Influential Factors in Cone-Beam Computed Tomography (CBCT) of the Head and Abdomen during Interventional Procedures.

Cone-beam computed tomography (CBCT) is a widely used imaging technique in interventional radiology. Although CBCT offers great advantages in terms of improving comprehension of complex angioarchitectures and guiding therapeutic decisions, its additional degree of radiation exposure has also aroused considerable concern. In this study, we aimed to assess radiation exposure and its influential factors in patients undergoing CBCT scans of the head and abdomen during interventional procedures. A total of 752 patients were included in this retrospective study. Dose area product (DAP) and reference air kerma (RAK) were used as measures of patient dose. The results showed that the median values of DAP were 53.8 (50.5-64.4) Gy⋅cm2 for head CBCT and 47.4 (39.6-54.3) Gy⋅cm2 for that of the abdomen. Male gender and body mass index (BMI) were characterized by increased DAP and RAK values in both head and abdominal CBCT scans. Larger FOV size was associated with a higher DAP but a lower RAK value, especially in head CBCT scans. Exposure parameters under automatic exposure control (AEC) also varied according to patient BMI and gender. In conclusion, the patients received slightly higher radiation doses from head CBCT scans than from those applied to the abdomen. BMI, gender, and FOV size were the key factors that influenced the radiation dose administered to the patients during CBCT scans. Our results may help to define and minimize patients' exposure to radiation.

Acute Impacts of Ionizing Radiation Exposure on the Gastrointestinal Tract and Gut Microbiome in Mice.

Radiation therapy for abdominopelvic malignancies often results in damage to the gastrointestinal tract (GIT) and permanent changes in bowel function. An overlooked component of the pathophysiology of radiation-induced bowel injury is the role of the gut microbiome. The goal of this research was to identify the impacts of acute radiation exposure on the GIT and gut microbiome. C57BL/6 mice exposed to whole-body X-rays (0.1-3 Gy) were assessed for histological and microbiome changes 48 h post-radiation exposure. Within the ileum, a dose of 3 Gy significantly decreased crypt depth as well as the number of goblet cells, but increased overall goblet cell size. Overall, radiation altered the microbial distribution within each of the main phyla in a dose- and tissue-dependent manner. Within the Firmicutes phylum, high dose irradiation resulted in significant alterations in bacteria from the class Bacilli within the small bowels, and from the class Clostridia in the large bowels. The 3 Gy radiation also significantly increased the abundance of bacterial families from the Bacteroidetes phylum in the colon and feces. Overall, we identified various alterations in microbiome composition following acute radiation exposure, which could potentially lead to novel biomarkers for tracking patient toxicities or could be used as targets for mitigation strategies against radiation damage.

Senescence-Associated Heterochromatin Foci Suppress γ-H2AX Focus Formation Induced by Radiation Exposure.

DNA damage is induced by both endogenous and exogenous factors. Repair of DNA double-strand break (DSB), a serious damage that threatens genome stability, decreases with senescence. However, the molecular mechanisms underlying the decline in DNA repair capacity during senescence remain unclear. We performed immunofluorescence staining for phosphorylated histone H2AX (γ-H2AX) in normal human fetal lung fibroblasts and human skin fibroblasts of different ages after chronic irradiation (total dose, 1 Gy; dose rate, 1 Gy/day) to investigate the effect of cellular senescence and organismal aging on DSB repair. Accumulation of DSBs was observed with cellular senescence and organismal aging, probably caused by delayed DSB repair. Importantly, the formation of γ-H2AX foci, an early event in DSB repair, is delayed with cellular senescence and organismal aging. These results suggest that the delay in γ-H2AX focus formation might delay the overall DSB repair. Interestingly, immediate γ-H2AX foci formation was suppressed in cells with senescence-associated heterochromatin foci (SAHF). To investigate the relationship between the γ-H2AX focus formation and SAHF, we used LiCl to relax the SAHFs, followed by irradiation. We demonstrated that LiCl rescued the delayed γ-H2AX foci formation associated with cellular senescence. This indicates that SAHF interferes with γ-H2AX focus formation and inhibits DSB repair in radiation-induced DSB. Our results suggest that therapeutic targeting of SAHFs have potential to resolve DSB repair dysfunction associated with cellular senescence.

Progression of Notch signaling regulation of B cells under radiation exposure.

With the continuous development of nuclear technology, the radiation exposure caused by radiation therapy is a serious health hazard. It is of great significance to further develop effective radiation countermeasures. B cells easily succumb to irradiation exposure along with immunosuppressive response. The approach to ameliorate radiation-induced B cell damage is rarely studied, implying that the underlying mechanisms of B cell damage after exposure are eager to be revealed. Recent studies suggest that Notch signaling plays an important role in B cell-mediated immune response. Notch signaling is a critical regulator for B cells to maintain immune function. Although accumulating studies reported that Notch signaling contributes to the functionality of hematopoietic stem cells and T cells, its role in B cells is scarcely appreciated. Presently, we discussed the regulation of Notch signaling on B cells under radiation exposure to provide a scientific basis to prevent radiation-induced B cell damage.

Intravenous immunoglobulin protects the integrity of the intestinal epithelial barrier and inhibits ferroptosis induced by radiation exposure by activating the mTOR pathway.

Radiation exposure often leads to serious health problems in humans. The intestinal epithelium is sensitive to radiation damage, and radiation causes destruction of the intestinal epithelial barrier, which leads to radiation enteritis (RE), the loss of fluids, and the translocation of intestinal bacteria and toxins; radiation can even threaten survival. In this study, we aimed to explore the influence of IVIg on the integrity of the intestinal epithelial barrier after RE. Using a RE mouse model, we investigated the protective effects of intravenous immunoglobulin (IVIg) on the epithelial junctions of RE mice and validated these findings with intestinal organoids cultured in vitro. In addition, transmission electron microscopy (TEM), western blotting (WB) and immunostaining were used to further investigate changes in intestinal epithelial ferroptosis and related signaling pathways. When RE occurs, the intestinal epithelial barrier is severely damaged. IVIg treatment significantly ameliorated this damage to epithelial tight junctions both in vivo and in vitro. Notably, IVIg alleviated RE by inhibiting intestinal epithelial ferroptosis in RE mice. Mechanistically, IVIg promoted activation of the mTOR pathway and inhibited ferroptosis in the intestinal epithelium of mice. Rapamycin, which is a potent inhibitor of the mTOR protein, significantly abolished the protective effect of IVIg against radiation-induced damage to intestinal epithelial tight junctions. Overall, IVIg can prevent RE-induced damage to the intestinal epithelial barrier and inhibit ferroptosis by activating the mTOR pathway; this study provides a new treatment strategy for patients with RE caused by radiotherapy or accidental nuclear exposure.

Radiation levels outside a patient undergoing177Lu-PSMA radioligand therapy.

Understanding the spatial distribution of radiation levels outside of a patient undergoing177Lu radioligand therapy is not only helpful for conducting correct tests for patient release, but also useful for estimation of its potential exposure to healthcare workers, caregivers, family members, and the general public. In this study, by mimicking the177Lu-labeled prostate-specific membrane antigen radioligand therapy for prostate cancers in an adult male, the spatial distribution of radiation levels outside of the phantom was simulated based on the Monte Carlo software of Particle and Heavy Ion Transport System, and verified by a series of measurements. Moreover, the normalized dose rates were further formulized on the three transverse planes representing the heights of pelvis, abdomen and chest. The results showed that the distributions of radiation levels were quite complex. Multi-directional and multi-height measurements are needed to ensure the external dose rate to meet the release criteria. In general, the radiation level was higher at the horizontal plane where the source was located, and the levels in front and behind of the body were higher than those of the left and right sides at the same height. The ratio of simulated dose rates to measured ones ranged from 0.82 to 1.19 within 1 m away from the body surface in all directions. Based on the established functions, the relative root mean square deviation between the calculated and simulated values were 0.21, 0.25 and 0.23 within a radius of 1 m on the pelvis, abdomen and chest transverse planes, respectively. It is expected that the results of this study would be helpful for guiding the test of extracorporeal radiation to determine the patient's release, and of benefit to estimate the radiation exposure to others.

Trends of occupational exposure to ionizing radiation in Central China for the period 2000-2021.

A retrospective analysis of occupational exposure to ionizing radiation from medical uses and industrial uses in the three provinces of Central China from 2000 to 2021 was conducted. The average annual effective dose in medical uses and industrial uses decreased from 2.042 mSv and 2.334 mSv in 2000-2002 to 0.476 mSv and 0.371 mSv in 2021 respectively; the fraction of monitored workers receiving annual dose not exceeding 1 mSv increased from 60.78% and 74.45% in 2000-2002 to 94.20% and 96.85% in 2021 respectively, while receiving annual doses exceeding 20 mSv declined from 1.35% and 1.91% in 2000-2002 to 0.18% and 0.03% in 2021 respectively. The average annual effective dose and NR20 in the period 2000-2021 were relatively high in professional public health institutions (0.955 mSv and 0.004) and hospitals (0.815 mSv and 0.004). In 2021, the average annual effective dose to monitored workers in different occupational categories in medical uses in the three provinces of Central China were in the range of 0.199-0.692 mSv, with interventional radiology received the highest dose and NR20 (0.692 mSv and 0.005); the average annual effective dose ranged from 0.161 to 0.493 mSv in industrial uses, with industrial radiography received the highest dose and NR20 (0.493 mSv and 0.001). Occupational exposure in medical uses and industrial uses declined obviously in Central China, and the groups receiving higher doses are the radiation workers working in hospitals and professional public health institutions, or engaged in interventional radiology, nuclear medicine and industrial radiography, warranting more effective radiation protection measures.

Advanced Interventional Treatments in Retinoblastoma Management: A Comprehensive Review.

Retinoblastoma is the most common eye malignancy in children that if left untreated can invade intraocular structures, metastasize, and rarely lead to death. Traditionally treated with systemic chemotherapy, Intra-arterial chemotherapy is gaining popularity as it allows for the direct administration of chemotherapy through the ophthalmic artery, thus reducing systemic side effects. Intra-arterial chemotherapy procedures have evolved, with refinements to reduce risks and radiation exposure. Intra-arterial chemotherapy boasts an impressive technical success rate and one year ocular survival even amongst advanced cases. This review offers a thorough examination of the technique, indications, contraindications, outcomes, and alternative options for Intra-arterial chemotherapy.

Trends in the use of radiation protection and radiation exposure of European endourologists: a prospective trial from the EULIS-YAU Endourology Group.

INTRODUCTION: Due to the radiation exposure for the urology staff during endourology, our aim was to evaluate the trends of radiation protection in the operation room by endourologists from European centers and to estimate their annual radiation. METHODS: We conducted a multicenter study involving experienced endourologists from different European centers to evaluate whether the protection and threshold doses recommended by the International Commission on Radiation Protection (ICRP) were being followed. A 36-question survey was completed on the use of fluoroscopy and radiation protection. Annual prospective data from chest, extremities, and eye dosimeters were collected during a 4-year period (2017-2020). RESULTS: Ten endourologists participated. Most surgeons use lead aprons and thyroid shield (9/10 and 10/10), while leaded gloves and caps are rarely used (2/10 both). Six out of ten surgeons wear leaded glasses. There is widespread use of personal chest dosimeters under the apron (9/10), and only 5/10 use a wrist or ring dosimeter and 4 use an eye dosimeter. Two endourologists use the ALARA protocol. The use of ultrasound and fluoroscopy during PCNL puncture was reported by 8 surgeons. The mean number of PCNL and URS per year was 30.9 (SD 19.9) and 147 (SD 151.9). The mean chest radiation was 1.35 mSv per year and 0.007 mSv per procedure. Mean radiation exposure per year in the eyes and extremities was 1.63 and 11.5 mSv. CONCLUSIONS: Endourologists did not exceed the threshold doses for radiation exposure to the chest, extremities and lens. Furthermore, the ALARA protocol manages to reduce radiation exposure.