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Risk Management and Healthcare Policy 2021To optimize the maintenance of radiation shields, this study aims to analyze annual inspection files to assess the integrity of radiation shields and their associated...
PURPOSE
To optimize the maintenance of radiation shields, this study aims to analyze annual inspection files to assess the integrity of radiation shields and their associated factors with regard to defects in radiation shields in clinical settings.
METHODS
A multicenter cross-sectional study was conducted at hospitals in Saudi Arabia. The data from annual inspection files of 1019 clinical lead radiation shields were analyzed. The factors of shield shape, unit where a shield is used, shield thickness, short-term use and number of users were examined. In addition to the inspection file analysis, radiation attenuation measurements were obtained for a subset of shields to compare newly purchased shields with older shields. Statistical analyses were performed using Fisher's exact test and a -test.
RESULTS
The results show that the highest percentage of failing shields were found in the emergency unit, fluoroscopy unit and operation room with a failure of approximately 7.14%, 5.61%, and 3.98%, respectively, of these shields. Fluoroscopy and operation room units were statistically significantly associated with shield defects. There was no association between shield damage and shape of shield, shield thickness, short-term use or number of users. Radiation attenuation measurements were similar for new and older shields.
CONCLUSION
As fluoroscopy units and operating rooms have a higher percentage of damaged shields, it is recommended that the shields employed in these units should be regularly inspected more frequently than once a year. The study highlights that the shields' age, transmission measurements that confirm that the correct shields are purchased according to the required kVp, physical appearance, and cleanliness should be recorded in annual inspection files. This study highlights the need for uniform inspection files of radiation shields across hospitals. National and international organizations may apply these findings to develop appropriate recommendations.
PubMed: 33790671
DOI: 10.2147/RMHP.S298783 -
Scientific Reports Dec 2020With the growing risk of radiation exposure, there are growing interests in radiation shielding. Because most radiation shields are made from heavy metals, a need to...
With the growing risk of radiation exposure, there are growing interests in radiation shielding. Because most radiation shields are made from heavy metals, a need to develop a soft shield is raised to protect human body. However, because the shield can easily undergo a mechanical damage by an impact, it would be better to have self-repairing system in the shield. Here, we have fabricated an intrinsic self-healable soft shield for gamma ray by making acrylamide based hydrogel composite. The composite contains lead dioxide nanoparticles for gamma ray shielding and Laponite clays for self-repairing. Although the hydrogel contained a large amount of lead dioxide nanoparticles (3.23 M), the fabricated composites stretched beyond 1400% while showing a high attenuation coefficient of 0.1343 cm against gamma ray from a cobalt-60 source. Then a systematic study was performed to analyze self-healing properties and the 96.55% of maximum self-healing efficiency was obtained. We also analyzed a storage modulus of hydrogel and molecular weight of polyacrylamide to study an effect of gamma ray on the self-healing. The self-healing efficiency was decreased by a gamma ray because the radiation induces scissioning or covalent crosslinking in the chains.
PubMed: 33303837
DOI: 10.1038/s41598-020-78663-x -
Materials (Basel, Switzerland) Sep 2022This study proposes a high-performance magnetic shielding structure composed of MnZn ferrite and mu-metal film. The use of the mu-metal film with a high magnetic...
This study proposes a high-performance magnetic shielding structure composed of MnZn ferrite and mu-metal film. The use of the mu-metal film with a high magnetic permeability restrains the decrease in the magnetic shielding coefficient caused by the magnetic leakage between the gap of magnetic annuli. The 0.1-0.5 mm thickness of mu-metal film prevents the increase of magnetic noise of composite structure. The finite element simulation results show that the magnetic shielding coefficient and magnetic noise are almost unchanged with the increase in the gap width. Compared with conventional ferrite magnetic shields with multiple annuli structures under the gap width of 0.5 mm, the radial shielding coefficient increases by 13.2%, and the magnetic noise decreases by 21%. The axial shielding coefficient increases by 22.3 times. Experiments verify the simulation results of the shielding coefficient of the combined magnetic shield. The shielding coefficient of the combined magnetic shield is 16.5%. It is 91.3% higher than the conventional ferrite magnetic shield. The main difference is observed between the actual and simulated relative permeability of mu-metal films. The combined magnetic shielding proposed in this study is of great significance to further promote the performance of atomic sensors sensitive to magnetic field.
PubMed: 36234022
DOI: 10.3390/ma15196680 -
Biomedical Physics & Engineering Express Feb 2021Low-cost, portable electroencephalography (EEG) devices have become commercially available in the last 10 years. One such system, Emotiv's EPOC, has been modified to...
Low-cost, portable electroencephalography (EEG) devices have become commercially available in the last 10 years. One such system, Emotiv's EPOC, has been modified to allow event-related potential (ERP) research. Although the EPOC has been shown to provide data comparable to research-grade equipment and has been used in real-world settings, how EPOC performs without the electrical shielding, commonly used in research-grade laboratories, is yet to be systematically tested. In the current article we address this gap by conducting a simple EEG experiment in shielded and unshielded contexts. Participants (n = 13, mean age = 23.2 years, SD = 7.9) monitored the presentation of human versus wristwatch faces, responding whether the images were inverted or not. This method elicited the face-sensitive N170 ERP. In both shielded and unshielded contexts, the N170 amplitude was larger when participants viewed human faces and peaked later when a human face was inverted. More importantly, Bayesian analysis showed no difference in the N170 measured in the shielded and unshielded contexts. Further, the signal recorded in both contexts was highly correlated. The EPOC appears to reliably record EEG signals without a purpose-built electrically-shielded room.
Topics: Adult; Bayes Theorem; Electroencephalography; Evoked Potentials; Head; Humans; Young Adult
PubMed: 33482647
DOI: 10.1088/2057-1976/abdf37 -
Biomedical Journal Oct 2019To quantify image quality and radiation doses in regions adjacent to and distant from bismuth shields in computed tomography (CT).
BACKGROUND
To quantify image quality and radiation doses in regions adjacent to and distant from bismuth shields in computed tomography (CT).
METHODS
An American College of Radiology accreditation phantom with four solid rods embedded in a water-like background was scanned to verify CT number (CTN) accuracy when using bismuth shields. CTNs, image noise, and contrast-to-noise ratios (CNRs) were determined in the phantom at 80-140 kVp. Image quality was investigated on image portions in the zones adjacent (A zone) to and distant (D zone) from a bismuth shield. Surface radiation doses were measured using thermoluminescent dosimeters. Streak artefacts were graded on a 3-point-scale.
RESULTS
Changes in CTN caused by a bismuth shield resulted in changes in X-ray spectra. CTN changes were more apparent in the A zone than in the D zone, particularly for a low tube voltage. The degrees of CTN changes and image noise were proportional to the thickness of the bismuth shields. A 1-ply bismuth shield reduced surface radiation doses by 7.2%-15.5%. The overall CNRs were slightly degraded, and streak artefacts were acceptable.
CONCLUSIONS
Using a bismuth shield could result in significant CTN changes and perceivable artefacts, particularly for a superficial organ close to the shield, and is not recommended for quantification CT examinations or follow-up CT examinations.
Topics: Artifacts; Bismuth; Breast; Humans; Phantoms, Imaging; Radiation Dosage; Tomography, X-Ray Computed
PubMed: 31783995
DOI: 10.1016/j.bj.2019.04.004 -
Biomedical Physics & Engineering Express Feb 2023Radiation of thoracic computed tomography (CT) involves the breast although it is not considered an organ of interest. According to the International Commission on...
Radiation of thoracic computed tomography (CT) involves the breast although it is not considered an organ of interest. According to the International Commission on Radiological Protection (ICRP) No. 103, the breast is an organ with a high level of sensitivity when interacting with x-rays, increasing the potential risk of breast cancer. Therefore, the radiation dose must be optimized while maintaining image quality. The dose optimization can be accomplished using a radiation shield. This study aims to determine the effect of silicone rubber (SR)-lead (Pb) in various thicknesses as an alternative protective material limiting dose and preserving the image quality of the breast in thoracic CT. SR-Pb was made from SR and Pb by a simple method. The SR-Pb had thicknesses of 3, 6, 9, and 12 mm. The breast dose was measured using a CT dose profiler on the surface of the breast phantom. The CT number and the noise level of the resulting image were determined quantitatively. The dose without the radiation shield was 5.4 mGy. The doses measured using shielding with thicknesses of 3, 6, 9, and 12 mm were 5.2, 4.5, 4.3, and 3.3 mGy, respectively. Radiation shielding with a thickness of 12 mm reduced breast surface dose by up to 38%. The CT numbers and noise levels for the left and right breast phantom images were almost the same as those without radiation shields indicating there were only slight artifacts in the image. Therefore, SR-Pb is considered a good shielding material which can be pplied in a clinical setting by placing it directly on the breast surface for dose optimization.
Topics: Silicone Elastomers; Lead; Radiation Dosage; Bismuth; Tomography, X-Ray Computed
PubMed: 36689768
DOI: 10.1088/2057-1976/acb551 -
Techniques in Vascular and... Mar 2018Many interventionalists face physical challenges almost daily for years or decades. The burden of assuming awkward positions while carrying extra weight can take its... (Review)
Review
Many interventionalists face physical challenges almost daily for years or decades. The burden of assuming awkward positions while carrying extra weight can take its toll on the musculoskeletal system to such an extent that the career is ended or modified to exclude procedural aspects. The proliferation of lighter aprons has unfortunately resulted in reduced protection with poor correlation of protection to labeling due to the inadequacies of testing methods for nonlead materials. The protective quality of the non-leads is not superior to lead-containing composites on a weight basis, and the user no longer knows how well they are protected unless buying aprons containing lead. Various useful methods and shields that may reduce radiation exposure are supported by the floor, ceiling, table, or patient. The suspended personal radiation protection system is a recent development which provides substantially greater radiation protection than conventional lead aprons combined with other shields, while also taking all of the weight off of the operator. It is composed of an expansive and thick (1mm Pb equiv) apron with a large face-shield to protect the neck, head, and eyes, and is suspended overhead to provide motion in the x, y, and z planes. Exposures may also be substantially reduced by leaving the area during acquisition sequences and use of power injectors.
Topics: Equipment Design; Humans; Job Description; Lead; Musculoskeletal Diseases; Occupational Exposure; Occupational Health; Occupational Injuries; Posture; Protective Clothing; Protective Factors; Radiation Dosage; Radiation Exposure; Radiation Injuries; Radiation Protection; Radiologists; Radiology, Interventional; Risk Factors; Workforce
PubMed: 29472000
DOI: 10.1053/j.tvir.2017.12.003 -
Frontiers in Public Health 2015A nipple shield is a breastfeeding aid with a nipple-shaped shield that is positioned over the nipple and areola prior to nursing. Nipple shields are usually recommended... (Review)
Review
INTRODUCTION
A nipple shield is a breastfeeding aid with a nipple-shaped shield that is positioned over the nipple and areola prior to nursing. Nipple shields are usually recommended to mothers with flat nipples or in cases in which there is a failure of the baby to effectively latch onto the breast within the first 2 days postpartum. The use of nipple shields is a controversial topic in the field of lactation. Its use has been an issue in the clinical literature since some older studies discovered reduced breast milk transfer when using nipple shields, while more recent studies reported successful breastfeeding outcomes. The purpose of this review was to examine the evidence and outcomes associated with nipple shield use.
METHODS
A literature search was conducted in Ovid MEDLINE, OLDMEDLINE, EMBASE Classic, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL. The primary endpoint was any breastfeeding outcome following nipple shield use. Secondary endpoints included the reasons for nipple shield use and the average/median length of use. For the analysis, we examined the effect of nipple shield use on physiological responses, premature infants, mothers' experiences, and health professionals' experiences.
RESULTS
The literature search yielded 261 articles, 14 of which were included in this review. Of these 14 articles, three reported on physiological responses, two reported on premature infants, eight reported on mothers' experiences, and one reported on health professionals' experiences.
CONCLUSION
Through examining the use of nipple shields, further insight is provided on the advantages and disadvantages of this practice, thus allowing clinicians and researchers to address improvements on areas that will benefit mothers and infants the most.
PubMed: 26528467
DOI: 10.3389/fpubh.2015.00236 -
Radiologic Technology Nov 2023To explore the data and supporting evidence for the 2019 statement by the American Association of Physicists in Medicine (AAPM) that recommends limits to the routine use... (Review)
Review
PURPOSE
To explore the data and supporting evidence for the 2019 statement by the American Association of Physicists in Medicine (AAPM) that recommends limits to the routine use of fetal and gonadal shielding in medical imaging.
METHODS
Three researchers searched 5 online databases, selecting articles from scholarly journals and radiology trade publications. Search results were filtered to include literature published from January 1, 2016, to August 9, 2022, to ensure relevance and provide historical background for the 2019 AAPM statement.
RESULTS
The use of patient shielding during medical imaging did not reduce dose, and in certain instances, increased dose received by patients during computed tomography, fluoroscopy, or dental imaging. The use of shielding interfered with technology designed to reduce patient dose, including automatic exposure control and dose modulation. Research showed that errors in shield placement were common and that shields can act as sources of infection or carriers of harmful lead dust.
DISCUSSION
In each article reviewed, a compelling case was made for discontinuing routine patient shielding during radiographic procedures. Serious opposition to the discontinuation of the shielding practice was not found. Opportunities exist for further study into technologists' and the public's understanding of the effects of radiation and technologists' compliance with new shielding policies.
CONCLUSION
The challenges with properly using shielding, paired with recent technological advancements and a new understanding of radiation protection, have negated the need for contact shielding. This legacy practice can be discontinued in clinical settings, and educational materials for technologists and students should be updated to reflect these changes.
Topics: Humans; Radiation Dosage; Tomography, X-Ray Computed; Radiation Protection; Fluoroscopy; Protective Devices
PubMed: 37940176
DOI: No ID Found -
Polymers Aug 2020A light-weight, flexible electromagnetic interference (EMI) shield was prepared by creating a layer-structured metal-polymer composite film consisting of electrospun...
A light-weight, flexible electromagnetic interference (EMI) shield was prepared by creating a layer-structured metal-polymer composite film consisting of electrospun nylon 66 nanofibers with silver films. The EMI shielding effectiveness (SE), specific SE, and absolute SE of the composite were as high as 60.6 dB, 67.9 dB cm/g, and 6792 dB cm/g in the X- and K-bands, respectively. Numerical and analytical calculations suggest that the energy of EM waves is predominantly absorbed by inter-layer multiple reflections. Because the absorbed EM energy is dissipated as heat, the thermal conductivity of absorption-dominant EMI shields is highly significant. Measured thermal conductivity of the composite was found to be 4.17 WmK at room temperature, which is higher than that of bulk nylon 66 by a factor of 16.7. The morphology and crystallinity of the composite were examined using scanning electron microscopy and differential scanning calorimetry, respectively. The enhancement of thermal conductivity was attributed to an increase in crystallinity of the nanofibers, which occurred during the electrospinning and subsequent hot pressing, and to the high thermal conductivity of the deposited silver films. The contribution of each fabrication process to the increase in thermal conductivity was investigated by measuring the thermal conductivity values after each fabrication process.
PubMed: 32796775
DOI: 10.3390/polym12081805