Increasing Radiation Dose Research Articles

Characterizing the Early Acidic Response in Advanced Small Modular Reactors Cooled with High-Temperature, High-Pressure Water

Utilizing Monte Carlo multi-track chemistry simulations along with a cylindrical instantaneous pulse (Dirac) irradiation model, we assessed the initial acidic response in both subcritical and supercritical water under high radiation dose rates. This investigation spans a temperature range of 300 to 500 °C at a nominal pressure of 25 MPa, aligning with the operational conditions anticipated in proposed supercritical water (SCW)-cooled small modular reactors (SCW-SMRs). A pivotal finding from our study is the observation of a significant ‘acid spike’ effect, which shows a notable intensification in response to increasing radiation dose rates. Our results bring to light the potential risks posed by this acidity, which could potentially foster a corrosive environment and thereby increase the risk of accelerated material degradation in reactor components.

Not All Flat-Panel C-Arms Are Created Equal: A Comparison of Three Major Manufacturers.

Introduction: Flat-panel detector C-arms (FCs) are reported to reduce radiation exposure and improve image quality compared with conventional image intensifier C-arms (CCs). The purpose of this study was to compare radiation exposure and image quality between three commonly used FCs. Materials and Methods: A cadaver model was placed in the prone position to simulate percutaneous nephrolithotomy. We compared the following three FCs: OEC Elite CFD from GE HealthCare, Zenition 70 from Philips, and Ziehm Vision RFD from Ziehm Imaging. To measure the radiation dose, optically stimulated luminescence dosimeters (OSLDs) were utilized during five 300-second trials, conducted under three settings: automatic exposure control (AEC), AEC with low dose (LD), and LD with the lowest pulse rate (LDLP). Ten blinded urologists evaluated the image quality. Data were statistically analyzed using the analysis of variance (ANOVA) and Tukey's B post hoc tests. Results: In the AEC setting, the Philips C-arm demonstrated lower ventral OSLD exposure (42,446 mrad) compared with both the GE (51,076 mrad) and Ziehm (83,178 mrad; p < 0.001) C-arms. Similarly, in the LD setting, the Philips C-arm resulted in less ventral OSLD exposure (25,926 mrad) than both the Ziehm (30,956 mrad) and GE (38,209 mrad; p < 0.001) C-arms. Meanwhile, in the LDLP setting, the Ziehm C-arm showed less ventral OSLD exposure (4019 mrad) than both the GE (7418 mrad) and Philips (8229 mrad; p < 0.001) C-arms. All three manufacturers received adequate image quality ratings at the AEC and LD settings. However, at LDLP, the Ziehm C-arm received inadequate ratings in 8% of images, whereas both the GE and Philips C-arms received 100% adequate ratings (p = 0.016). Conclusions: Radiation produced by flat-panel C-arms varies dramatically, with the highest exposure (Ziehm) being almost double the lowest (Philips) in AEC. Improved picture quality at the lowest settings may come at the cost of increased radiation dose. Surgeons should carefully select the machine and settings to minimize radiation exposure while still preserving the image quality.

Reproducible spectral CT thermometry with liver-mimicking phantoms for image-guided thermal ablation

Objectives. Evaluate the reproducibility, temperature tolerance, and radiation dose requirements of spectral CT thermometry in tissue-mimicking phantoms to establish its utility for non-invasive temperature monitoring of thermal ablations. Methods. Three liver mimicking phantoms embedded with temperature sensors were individually scanned with a dual-layer spectral CT at different radiation dose levels during heating (35 °C–80 °C). Physical density maps were reconstructed from spectral results using varying reconstruction parameters. Thermal volumetric expansion was then measured at each temperature sensor every 5 °C in order to establish a correlation between physical density and temperature. Linear regressions were applied based on thermal volumetric expansion for each phantom, and coefficient of variation for fit parameters was calculated to characterize reproducibility of spectral CT thermometry. Additionally, temperature tolerance was determined to evaluate effects of acquisition and reconstruction parameters. The resulting minimum radiation dose to meet the clinical temperature accuracy requirement was determined for each slice thickness with and without additional denoising. Results. Thermal volumetric expansion was robustly replicated in all three phantoms, with a correlation coefficient variation of only 0.43%. Similarly, the coefficient of variation for the slope and intercept were 9.6% and 0.08%, respectively, indicating reproducibility of the spectral CT thermometry. Temperature tolerance ranged from 2 °C to 23 °C, decreasing with increased radiation dose, slice thickness, and iterative reconstruction level. To meet the clinical requirement for temperature tolerance, the minimum required radiation dose ranged from 20, 30, and 57 mGy for slice thickness of 2, 3, and 5 mm, respectively, but was reduced to 2 mGy with additional denoising. Conclusions. Spectral CT thermometry demonstrated reproducibility across three liver-mimicking phantoms and illustrated the clinical requirement for temperature tolerance can be met for different slice thicknesses. The reproducibility and temperature accuracy of spectral CT thermometry enable its clinical application for non-invasive temperature monitoring of thermal ablation.

Study of risk factors for cataracts in a chronically exposed population cohort

BACKGROUND: The likelihood of developing cataracts is influenced by many factors, such as age, gender, ethnicity, the presence of somatic pathology (diabetes mellitus, hypertension), dietary habits and lifestyle (obesity, level of education), etc.&#x0D; AIM: To study the risk of developing cataracts in exposed people in the long term after chronic radiation exposure, taking into account the influence of radiation dose and non-radiation factors.&#x0D; MATERIAL AND METHODS: The total study group consisted of 14,751 people examined in the hospital of the Ural Scientific and Practical Center for Radiation Medicine from 1955 to 2019. Cataracts were diagnosed in 4,658 people. The statistical methods were based on case-control. To assess the association of the studied factors with the risk of developing cataracts, the odds ratio (OR) and 95% confidence interval (CI) were calculated. Morbidity rates were calculated using medical statistics methods per 1000 people. When studying the incidence of cataracts, individualized indicators of radiation dose to the lens of the eye were used.&#x0D; RESULTS: The study revealed an increase in the incidence of cataracts as the cohort ages. There was a tendency for the risk of cataracts to increase (OR=1.10; 95% CI=1.00–1.21) with increasing radiation dose. The incidence of cataracts was associated with the presence of arterial hypertension (OR=2.01; 95% CI=1.81–2.22), diabetes mellitus (OR=1.36; 95% CI=1.17–1.58), cerebrovascular diseases (OR=1.14; 95% CI=1.03–1.26), increased body mass index (OR=1.61; 95% CI=1.45–1.78), as well as belonging to Turkic group (OR=1.58; 95% CI=1.44–1.71), living in the city (OR=1.26; 95% CI=1.15–1.38), having no family (OR=1.72; 95% CI=1.63–1.97), employment primarily in mental work (OR=1.34; 95% CI=1.22–1.48).&#x0D; CONCLUSION: A tendency for the influence of radiation dose on an increase in the risk of cataracts has been established, medical and social factors that increase the likelihood of developing senile cataracts have been identified.

Evaluasi Nilai Diagnostic Reference Level (DRL) pada pemeriksaan CT Scan Thorax Kontras klinis tumor paru di RS X Jakarta

A contrast thorax CT scan is a CT scan procedure in the chest area (thorax) that uses a contrast agent to improve visualization of organs and structures in the chest. Lung tumors are the growth of abnormal lumps in lung tissue which can be benign or malignant. Awareness of the potential and increasing radiation dose in all CT scan examinations encourages radiographers to want and be able to minimize radiation exposure as the main goal in radiological examinations and also strive for radiation protection during examinations. CT scan radiation dose accounts for 70% of the total dose received from medical imaging. High or low doses of radiation received can increase the risk of cancer. The large dose of radiation received by a patient during a CT scan, therefore regulations are needed that will guarantee monitoring of the radiation dose received by the patient to ensure that the dose received is commensurate with medical purposes. The radiation dose to the patient needs to be optimized by applying the Diagnostic Reference Level (DRL) to optimize medical exposure protection for the patient. Dosage evaluation in clinical contrast chest CT scan examinations for lung tumors and the application of DRL in these examinations have never been carried out at RS X Jakarta. Objective: This study aims to determine the DRL value in clinical contrast thorax CT scan examination of lung tumors at RS CTDIvol and DLP values from clinical contrast Thorax CT Scan examination of lung tumors. The DRL value is calculated at Quartile 3 (75 percentile) using the descriptive frequency test and Wilcoxon test in the SPSS application, then compared with the latest IDRL value. Results: Quartile 3 value (75 percentile) from CTDIvol and DLP CT scan chest contrast clinical lung tumors, namely The CTDIvol value was 12.55 mGy and the DLP was 439 mGy.cm. Conclusion: The DRL value in the clinical contrast thorax CT scan for lung tumors at Hospital X Jakarta. is still below the recommended standard, which shows that the radiation output dose in this examination practice is within normal limits and is classified as safe.

Irradiation Hardening and Microstructure Study of MAX-Phase-Dispersion-Strengthened Vanadium Alloy under Self-Ion Irradiation

V-4Cr-4Ti alloy is one of the candidate structural materials for future fusion reactors due to its desirable characteristics. In our previous research, MAX-phase-dispersion-strengthened vanadium alloy (V-4Cr-4Ti-1.5Y-0.3Ti3SiC2), prepared through mechanical alloying, showed excellent thermal stability and creep resistance and was expected to have good radiation resistance. This study investigates the effects of 2.5 MeV V2+ ion irradiation on V-4Cr-4Ti-1.5Y-0.3Ti3SiC2 and V-4Cr-4Ti alloys at 500 °C, with peak damage of 0.8, 3.5, and 6.1 dpa. Transmission electron microscopy and nanoindentation were used to examine the changes in microstructure and hardness before and after irradiation. The microscopic analysis reveals that dispersed nanoparticles maintained good stability under irradiation. Defect clusters grow with increasing irradiation doses in both materials. The nanoindentation results show that V-4Cr-4Ti-1.5Y-0.3Ti3SiC2 has higher initial hardness and lower irradiation hardening, indicating better resistance to radiation hardening than V-4Cr-4Ti. This research serves as a valuable reference for the assessment of the irradiation resistance of Ti3SiC2-dispersion-strengthened V-4Cr-4Ti alloy.

Effect of gamma irradiation on microbial growth, physicochemical properties, and non‐volatile flavour of chicken sausages during storage

SummaryEffects of 60Co‐γ ray irradiation on physicochemical properties and non‐volatile flavour changes of chicken sausage during storage were investigated. Gamma irradiation at high doses effectively inhibited microbial growth and retarded physicochemical deterioration of chicken sausages throughout the storage period. The total fatty acid, saturated, and polyunsaturated fatty acids increased and decreased with increasing irradiation dose. In contrast, the monounsaturated acid content decreased with increasing irradiation dose. The free amino acid content exhibited a reduction of 4.27% following irradiation at a dose of 6 kGy and this decrease was further intensified during storage. Tartaric acid and pyruvate were chicken sausage's main organic acids and the most important taste‐active compounds. The irradiation dose had no significant effect on the organic acid content of chicken sausages, which continued to decrease during storage. The degradation products of nucleotides in irradiated chicken sausages demonstrated a noteworthy reduction in AMP and IMP, with no significant alterations observed in the remaining products. Thus, appropriate irradiation treatment (3 kGy) could effectively prolong the shelf life of chicken sausages without affecting their overall quality and had no adverse effects on the non‐volatile flavour compounds.

Usefulness of the spectral shaping dual-source computed tomography imaging technique in posterior corrective fusion for adolescent idiopathic scoliosis.

Since childhood exposure to radiation has been demonstrated to increase cancer risk with increase in radiation dose, reduced radiation exposure during computed tomography (CT) evaluation is desired for adolescent idiopathic scoliosis (AIS). Therefore, this retrospective study aimed to investigate the radiation dose of dual-source CT using a spectral shaping technique and the accuracy of the thoracic pedicle screw (TPS) placement for posterior spinal fusion (PSF) in patients with AIS. Fifty-nine female patients with thoracic AIS who underwent PSF using CT-guided TPSs were included and divided into two groups comprised of 23 patients who underwent dual-source CT (DSCT) with a tin filter (DSCT group) and 36 who underwent conventional multislice CT (MSCT group). We assessed the CT radiation dose using the CT dose index (CTDIvol), effective dose (ED), and accuracy of TPS insertion according to the established Neo's classification. The DSCT and MSCT groups differed significantly (p < 0.001) in the mean CTDIvol (0.76 vs. 3.31mGy, respectively) and ED (0.77 vs. 3.47mSv, respectively). Although the correction rate of the main thoracic curve in the DSCT group was lower (65.7% vs. 71.2%) (p = 0.0126), the TPS accuracy (Grades 0-1) was similar in both groups (381 screws [88.8%] vs. 600 screws [88.4%], respectively) (p = 0.8133). No patient required replacement of malpositioned screws. Spectral shaping DSCT with a tube-based tin filter allowed a 75% radiation dose reduction while achieving TPS insertion accuracy similar to procedures based on conventional CT without spectral shaping.

Effect of electron beam irradiation on the structural characteristics and functional properties of goat's milk casein

The effects of electron beam irradiation (EBI) at different doses (0, 2, 4, 6, 8, and 10 kGy) were investigated on the structural and functional properties of casein, including their interrelationship. A gradual reduction in the α-helix content of the secondary structure (as a stable structure) indicates that casein under EBI treatment mainly undergoes fragmentation and aggregation from a structural perspective. Furthermore, the hydrophobic group and tryptophan in the tertiary structure were exposed, which opened up the internal structure of the protein. In addition, a continuously increasing irradiation dose led to casein aggregation, as confirmed by electron microscopy. The structural changes affected its functional properties, such as solubility, emulsification, foaming, and rheological properties, all of which increased first and subsequently decreased. Finally, at irradiation doses of 4–6 kGy, casein was modified to exhibit optimal functional properties, which enhanced its food processing value and performance.

Electron beam pre-irradiation enhances substitution degree, and physicochemical and functional properties of carboxymethyl peanut shell nanocellulose

Nanocellulose (NC) has attracted close attention in research and industry fields because of its excellent properties and plentiful hydroxyl group accessible for surface modification. In this study, the cellulose isolated from peanut shells was used to prepare carboxymethylated nanocellulose (CMNC) under different reaction conditions, and Electron beam irradiation (EBI) pretreatment with different doses (40, 80 and 120 KGy) was previously used before modification to improve the reaction accessibility of nanocellulose. The substitution degree (DS), structural, physicochemical and functional properties of carboxymethyl CMNC with EBI pretreatment were investigated. The results showed that the peanut shell nano cellulose was a typical rod-like structure with a diameter of 5–40 nm and a length of 50–300 nm, the aspect ratio distribution was about 6.37, and EBI pretreatment significantly improved the modification effect of CMNC. The DS of the unirradiated sample was 0.38 and 0.48, and the DS increased to 0.66 and 0.69 at the irradiation dose of 120 kGy, which increased by 74% and 44%, respectively. The carboxymethyl modification changed the morphology of nanocellulose from the original short rod-like to spherical particles, and the effect was more evident with the increase of irradiation dose. FTIR showed that the nanocellulose successfully introduced carboxyl groups, the crystalline structure of nanocellulose was changed by carboxymethyl reaction. The Zeta potential result showed that the dispersion stability of CMNC suspension was improved. These results provide a helpful basis for further investigations on the modification in nanocellulose induced by EBI, verifying the effectiveness and feasibility of using EBI to modify nanofibers. They are expected to guide the transformation of nanocellulose and its most possible applications in the future to improve its performance in different applications.

Evaluating therapeutic efficacy of extended shelf-life 90 Y glass microspheres in transarterial radioembolization for colorectal cancer: a quantitative FDG PET/CT analysis.

There is a lack of sufficient evidence regarding the use of extended shelf-life (ExSL) Yttrium-90 ( 90 Y) glass radiomicrospheres in metastatic colorectal cancer (mCRC) patients. We aimed to investigate the efficacy of ExSL 90 Y glass radiomicrospheres with a personalized treatment approach by analyzing 18 F-FDG PET/CT quantitative parameters [metabolic tumor volume (MTV) and total lesion glycolysis (TLG)] separately before and after the treatment. A total of 93 radioembolization sessions involving 77 patients were included. Simplicit 90 Y software was utilized to perform multicompartmental voxel-based dosimetry. Adverse events were recorded using the CTCAE v5.0 criteria. The survival data were recorded in detail. The overall disease control rate was 84.9%, with a median overall survival (OS) of 12.7 months and median progression-free survival (PFS) of 8.3 months. A statistically significant increase in treatment response rate was observed when there was an increase in absorbed tumor dose for pre-treatment unit MTV ( P = 0.005) and TLG ( P = 0.004) values. We didn't observe any additional side effects/vital risks that could be considered clinically significant. Our study has provided evidence on the therapeutic effectiveness and safety in terms of dose-toxicity profile of ExSL 90 Y glass microspheres in a large cohort of mCRC patients. With a personalized treatment approach, the increase in radiation dose absorbed by the tumor has shown a significant contribution to treatment response rate, as indicated by quantitative measurements obtained through 18 F-FDG PET/CT.

Helium bubble evolution under cascade in bcc iron relevant to fusion conditions investigated by a novel coupling MD-OKMC method

The direct interaction between cascade and helium bubbles during the thermal spike phase plays an important role in the helium bubbles evolution in metals, which was not fully considered by the present long-time simulation methods. To address this issue, in this work we developed a coupling MD-OKMC method to investigate the helium bubble evolution under irradiation cascade in bcc iron. The short-time collision cascade was simulated by the molecular dynamics (MD), and the long-time helium bubble evolution was modeled by the object kinetic Monte Carlo (OKMC). The MD and OKMC simulations were alternated to imitate the gradual increase of both irradiation dose and helium concentration under experiment conditions. The impact of temperature on the helium bubble evolution under irradiation cascade in bcc iron was investigated and the results were compared with the data from neutron irradiation experiment. It's found that the results of the coupling MD-OKMC were consistent with the experiment results, and were better in agreement with the experiment than the traditional OKMC.

The Structure and Properties of Medical Disposable Protective Clothing Materials with Different Packaging and Models under γ Irradiation

AbstractThis study investigated the radiation effects of commercially available medical disposable protective clothing materials under γ irradiation. FT‐IR, contact angle, DSC, OIT, and mechanical properties were used to examine the radiation effects of medical disposable protective clothing materials. The results showed when the radiation dose was less than or equal to 50 kGy, the FT‐IR spectra did not show any changes. However, when the radiation dose reached 70 kGy, new absorption peaks appeared in the infrared spectra of the TS−A and TS−B medical disposable protective clothing materials, indicating chemical changes. Contact angle analysis showed that medical disposable protective clothing materials were hydrophobic and had higher hydrophobicity on the inside than the outside under different packaging and irradiation conditions. Rheological analysis showed that the shear thinning phenomenon of medical disposable protective clothing materials increased significantly with the increase of radiation dose, and good rheological behavior was observed under vacuum packaging conditions when the radiation dose was 30 kGy. The crystallinity and initial crystallization temperature showed the order of vacuum, nitrogen, and air. The oxidation induction time trend was vacuum&gt;nitrogen&gt;air, while the fracture strength trend was nitrogen&gt;vacuum&gt;air. The mechanical properties met the national standard.

Enhancing gamma irradiation resistance by a‐C film treatment on polytetrafluoroethylene (PTFE) surface

Polytetrafluoroethylene (PTFE) solid self‐lubricating materials exhibit inferior tribological properties in the gamma‐irradiated environment. In this paper, amorphous hydrogen‐free carbon (a‐C) film was deposited on the PTFE polymer surface by magnetron sputtering, and the a‐C/PTFE samples were irradiated with gamma ray at a maximum dose of up to 5 MGy. The evolution of the structure and nanomechanical and tribological properties of a‐C/PTFE with different irradiation doses were investigated. The structural analyses reveal that the microstructure of a‐C films irradiated at 5 MGy doses is stable. Due to the covering of the a‐C film, significant cracks appear at the surface of the a‐C/PTFE sample only when the irradiation dose reaches 5 MGy. Before and after irradiation, the nanohardness and Young's modulus of the a‐C/PTFE are significantly higher than those of PTFE. The mechanical properties of PTFE are improved by a‐C film surface treatment. The friction experiments show that the average friction coefficients of both a‐C/PTFE and PTFE remain stable around 0.175 with increasing irradiation dose. When the irradiation dose is within 1 MGy, frictional behaviors occur only on the surface of a‐C films, and the wear rate of a‐C/PTFE is as low as 9.3 × 10−5 mm3/N.m, which is significantly lower than that of PTFE. The method of a‐C film treatment on the PTFE surface can dramatically improve the irradiation resistance of PTFE.

Sensitivity of developmental stages of pulse beetle Callosobruchus maculatus (F.) to gamma rays

Sensitivity studies on effects of gamma radiation on different life stages of Callasobruchus maculatus (F.) werecarried out in a growth chamber at temperature of 30ºC and relative humidity of 70 per cent. Two days old eggs, grubs (fourand seventeen days old) and three days old pupae along with green gram seeds were exposed to gamma radiation in range of0-50 Gy, 0-60 Gy, 0-100 Gy and 0-100 Gy, respectively. The radiation doses like 15 Gy, 40 Gy, 100 Gy and 100 Gy wereeffectively prevented adult formation from treated pre-imaginal stages mentioned above. For adult beetles response wasassessed by selecting five pairs of four days old adult male and females along with 30 g greengram seeds kept as a food andwere exposed to gamma radiation in range of 0-140 Gy. The fecundity of adults decreased with the increase of irradiationdose. There was 54.02, 61.59, 69.07, 87.80, 94.36 and 97.45 per cent reduction in egg laying in adults exposed to 20, 40, 60,80, 100 and 120 Gy, respectively. The adults exposed to a radiation dose of 80 Gy and above were capable of egg laying butsuch eggs were not developed to form adult . Therefore, from this study we concluded that all stages of C. maculatus canbe killed at 120 to 150 Gy expose dosage of gamma radiation.

Cone-beam computed tomography in implant dentistry - guidelines, current concepts and limitations for practice

This article issues scientific background of Cone-beam computed tomography (CBCT) and the importance of taking x-rays before and after implant placement in daily practice as a common care. The review will introduce cone-beam computed tomography guidelines, restrictions and intraoperartive issues for instance nerve damage and bleeding incidents. Modern CBCT technology enables specialists to avoid making a wrong diagnosis, which translates into a higher percentage of people with a positive treatment outcome.&#x0D; Diagnostic radiology is a crucial element of every dental treatment planning. CBCT market is expanding gradually since two decades, there are more than 85 distinct CBCT tools available. CBCT is a three-dimensional (3D) imaging used nowadays in dentistry with increased frequency and offers volumetric data on jaw bones and teeth with relatively low radiation doses and costs. Currently, the greatest advantage of CBCT examinations over radiographs is the fact that the image obtained is presented in a 3D projection and not, as is the case, in 2D. It has the ability to help a wider range of patients, but the use of CBCT also has negative consequences. Routine or excessive use has resulted in increased radiation doses accumulating in the patient's body, which translates into an increased risk of adverse effects. The risk varies according to the age of the patient under study and is directly proportional to it, that is, it is highest for young people and lower for older people. The potential risk is also slightly higher in the female population. For this reason, creating awareness of the mandatory patient safety management of CT scans is a key process by which X-ray exposures can be optimised.

Određivanje optimalnih doza gama zračenja kod indukovanih mutacija pšenice i ječma

One of the major challenges that plant breeders face in the 21st century is food safety for growing human population coupled with extreme climate changes. Accordingly, the most important breeders' goal is to find appropriate methods in response to these challenges in order to create high-yielding varieties resilient to abiotic and biotic stressors. The aim of this study was to determine optimal doses of gamma irradiation in two wheat and one barley varieties and to apply the identified doses for development of mutant populations. Wheat and barley varieties showed different reactions to applied doses of gamma irradiation. Wheat varieties had germination rate over 90% at all applied doses while barley seeds showed to be more susceptible to gamma irradiation. Gamma irradiation had greater influence on seedling height which was clearly demonstrated by growth reduction with increasing radiation doses. ANOVA showed a significant difference between genotypes, applied doses of gamma radiation as well as genotype by doses interaction for seedling height. At highest dose of 600 Gy, the reduction of seedling height was 94.6%, 96.5% and 96.8% in Simonida, Rudnik and NS 40S, respectively. The irradiation doses that resulted in seedling growth reduction by 50% (GR50) were 210 Gy for barley Rudnik and wheat NS 40S, and 310 Gy for wheat variety Simonida. Identified doses were used for the irradiation of 2000 seeds of each variety in order to produce mutant populations that will be further used in a breeding program for development of varieties with increased resilience to climate change.

A narrative review of intraoperative adjuncts and techniques to minimize radiation during complex endovascular aneurysm repair

BackgroundRadiation exposure is a known risk to both patients and providers during endovascular aortic aneurysm repair (EVAR). Complex EVAR procedures, such as fenestrated and branched EVAR, inherently involve longer fluoroscopy times and increased radiation doses. While adhering to the as low as reasonably achievable principles and ensuring appropriate personal protective equipment for all operating room staff remains essential, the use of intraoperative techniques and adjuncts to decrease radiation specifically during complex EVAR is necessary. This review aims to summarize intraoperative radiation reduction techniques to provide valuable insights to vascular surgeons and interventional proceduralists to enhance radiation safety during complex EVAR. MethodsThis review focused on intraoperative techniques and adjuncts that have been used to decrease intraoperative radiation exposure to patients and operators. Published and presented preclinical results, prospective and retrospective study data, and future directions are presented. ResultsWe highlight several intraoperative adjuncts and techniques for reducing radiation exposure during complex EVAR including image fusion, digital zooming, intravascular ultrasound examination, Fiber Optic RealShape (FORS) technology, and robotic navigation systems. Short-term outcomes suggest that these techniques are safe, feasible, and effective and decrease radiation exposure to both patients and operators. ConclusionsDecreasing radiation exposure during complex EVAR remains of critical importance. The presented techniques offer promising avenues for significantly decreasing radiation exposure to both patients and providers while maintaining procedural efficacy during complex EVAR.

The effect of external radiation exposure per person depending on his position and anthropometric indicators

This study reviews existing methods for modelling the impact of ionising radiation sources on the human body. Using advanced modelling methods, the main modelling parameters are determined and it is revealed whether anthropometry affects the increase or decrease of the total radiation dose in the conditions of work in radiation-contaminated areas of the nuclear fuel cycle. The most rational and safe approach today is to conduct experimental studies on anthropomorphic mannequins to simulate human exposure using the RANDO phantom model with different geometries of exposure to ionising radiation sources. The considered modelling methods are taken from medicine, nuclear power, economics and labour protection, where they have found their application and continue to be improved. For further research, it is necessary to use other types of models, such as the Event Tree model, SWOT analysis model, Zero Risk model, Correlation and Regression System model, Matrix model, and other computer models and simulations using artificial intelligence. The factors proposed in this article provide a “complete picture” of the factors that occur in real conditions of research, measurements, service, security and physical protection of radiation-hazardous facilities such as tailing ponds of former uranium production.

Theoretical study on radiation effect on threshold of transverse mode instability of Yb-doped fiber amplifiers

&lt;sec&gt;Yb-doped fiber amplifiers and their applications in radiation environments have become more and more attractive in recent years. However, the radiation effect will cause damage to the Yb-doped fibers, which can give negative effect on the output properties of Yb-doped fiber amplifiers. In this work, the influence of radiation effect on the transverse mode instability (TMI) of Yb-doped fiber amplifier is studied. TMI can couple the single light from the fundamental mode to high-order mode, thereby degenerating the beam quality of fiber amplifier. TMI is considered a key limitation of power up-scaling of fiber amplifiers.&lt;/sec&gt;&lt;sec&gt;In this work, the radiation effect on the TMI is studied theoretically, and a formula of TMI threshold is presented by taking the radiation-induced attenuation (RIA), the most important radiation effect for the TMI, into account. The formula is deduced by introducing the loss of signal light induced by RIA into the formerly reported TMI-threshold formula which can be obtained by the linear stability analysis of the numerical model studying the TMI. Then, the relationship between the TMI and radiation dose is also given with the help of Power-Law describing the relationship between the RIA and radiation dose.&lt;/sec&gt;&lt;sec&gt;With the formula, the variations of TMI threshold with the radiation dose and RIA are studied. It is found, as expected, that the TMI threshold decreases monotonically with the increase of RIA or radiation dose. Nevertheless, it is unexpectedly found that, to some extent, the gain coefficient of fiber amplifiers will also affect the radiation effect on TMI threshold. The results reveal that the increase of gain coefficient will lower the sensitivity of TMI threshold to the radiation dose. However, it is also implied that the gain coefficient cannot be too large because it can also make the TMI threshold lowered. Therefore, in order to maintain a high TMI threshold in a radiation environment, sufficient radiation resistance of Yb-doped fiber is essential.&lt;/sec&gt;&lt;sec&gt;Because the RIA can affect not only the TMI threshold but also the output power or efficiency of Yb-doped fiber amplifier, the comparison between two effects of RIA is also discussed. It is found that the threshold of TMI is more sensitive to the radiation than to the output power or efficiency (see the figure attached below), which means that the TMI can exist in the irradiated Yb-doped fiber amplifier, although the output power is reduced because of RIA. This result can be verified by the experimental observation reported formerly. As a result, TMI can become a key limitation to the output power of Yb-doped fiber amplifier in radiation environments. The relevant results can provide significant guidance for the applications of Yb-doped fiber amplifiers in radiation environments.&lt;/sec&gt;