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PurposeTo perform a complete evaluation on radiation doses, received by primary and assistant medical staff, while performing different vascular interventional radiology procedures.Materials and methodsWe evaluated dose received in different body regions during three categories of vascular procedures: lower limb angiography (Angiography), lower limb percutaneous transluminal angioplasty (Angioplasty) and stent graft placement for abdominal aortic aneurysm treatment (A. A. A. Treatment). We positioned the dosimeters near the eye lens, thyroid, chest, abdomen, hands, and feet of the interventional physicians. Equivalent dose was compared with annual dose limits for workers in order to determine the maximum number of procedures per year that each physician could perform. We assessed 90 procedures.ResultsWe found the highest equivalent doses in the A. A. A. Treatment, in which 90% of the evaluations indicated at least one region receiving more than 1 mSv per procedure. Angioplasty was the only procedural modality that provided statistically different doses for different professionals, which is an important aspect on regards to radiological protection strategies. In comparison with the dose limits, the most critical region in all procedures was the eye lens.ConclusionsSince each body region of the interventionist is exposed to different radiation levels, dose distribution measurements are essential for radiological protection strategies. These results indicate that dosimeters placed in abdomen instead of chest may represent more accurately the whole body doses received by the medical staff. Additional dosimeters and a stationary shield for the eye lens are strongly recommended. 相似文献
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PurposeMost radiation protection programs, regulations and guidance apply specific restrictions to the occupational exposure of pregnant workers. The aim of this study was to compile data from the declared pregnant woman (DPW) radiation protection program over more than 5 years at a large, high-volume, comprehensive oncology academic/medical institution and to evaluate for effectiveness against existing regulations and guidance.MethodsA retrospective review was performed of the data collected as part of the DPW radiation protection program from January 2010 through May 2016, including the number of declared pregnancies, worker category, personal and fetal dosimetry monitoring measurements, workplace modifications, as well as the monthly and total recorded badge results during the entire pregnancy.Results245 pregnancies were declared. The mean monthly fetal radiation dosimetry result was 0.009 mSv with a median of 0.005 mSv and a maximum of 0.39 mSv. The mean total dose over the entire pregnancy was estimated to be 0.08 mSv with a median of 0.05 mSv and a maximum of 0.89 mSv. Only 8 (3.2%) of the 245 declared pregnancies required that workplace modifications be implemented for the worker.ConclusionsThe implementation of a declared pregnancy and fetal assessment program, careful planning, an understanding of the risks, and minimization of radiation dose by employing appropriate radiation safety measures as needed, can allow medical staff to perform procedures and normal activities without incurring significant risks to the conceptus, or significant interruptions of job activities for most medical workers. 相似文献
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M. Alkhorayef A. Sulieman H. Barakat H.I. Al-Mohammed K. Theodorou C. Kappas D. Bradley 《Saudi Journal of Biological Sciences》2021,28(1):35-39
Medical exposure of the general population due to radiological investigations is the foremost source of all artificial ionising radiation. Here, we focus on a particular diagnostic radiological procedure, as only limited data are published with regard to radiation measurements during urethrograpic imaging. Specifically, this work seeks to estimate patient and occupational effective doses during urethrographic procedures at three radiology hospitals. Both staff and patient X-ray exposure levels were calculated in terms of entrance surface air kerma (ESAK), obtained by means of lithium fluoride thermoluminescent dosimeters (TLD-100(LiF:Mg:Cu.P)) for 243 urethrographic examinations. Patient radiation effective doses per procedure were estimated using conversion factors obtained from the use of Public Health England computer software. In units of mGy, the median and range of ESAK per examination were found to be 10.8 (3.6–26.2), 7.0 (0.2–32.3), and 24.3 (9.0–32.0) in Hospitals A, B, and C, respectively. The overall mean and range of staff doses (in µGy) were found to be 310 (4.0–1750) per procedure. With the exception of hospital C, the present evaluations of radiation dose have been found to be similar to those of previously published research. The wide range of patient and staff doses illustrate the need for radiation dose optimisation. 相似文献
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PurposeOptimization of CT scan practices can help achieve and maintain optimal radiation protection. The aim was to assess centering, scan length, and positioning of patients undergoing chest CT for suspected or known COVID-19 pneumonia and to investigate their effect on associated radiation doses.MethodsWith respective approvals from institutional review boards, we compiled CT imaging and radiation dose data from four hospitals belonging to four countries (Brazil, Iran, Italy, and USA) on 400 adult patients who underwent chest CT for suspected or known COVID-19 pneumonia between April 2020 and August 2020. We recorded patient demographics and volume CT dose index (CTDIvol) and dose length product (DLP). From thin-section CT images of each patient, we estimated the scan length and recorded the first and last vertebral bodies at the scan start and end locations. Patient mis-centering and arm position were recorded. Data were analyzed with analysis of variance (ANOVA).ResultsThe extent and frequency of patient mis-centering did not differ across the four CT facilities (>0.09). The frequency of patients scanned with arms by their side (11–40% relative to those with arms up) had greater mis-centering and higher CTDIvol and DLP at 2/4 facilities (p = 0.027–0.05). Despite lack of variations in effective diameters (p = 0.14), there were significantly variations in scan lengths, CTDIvol and DLP across the four facilities (p < 0.001).ConclusionsMis-centering, over-scanning, and arms by the side are frequent issues with use of chest CT in COVID-19 pneumonia and are associated with higher radiation doses. 相似文献
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To derive effective dose (E), organ dose (HT) and conversion factors with the air kerma area product (KAP) in coronary angiography (CA) and percutaneous coronary intervention (PCI) by the radial route, using the ICRP 103 tissue weighting factors.The study included 34 patients referred for CA and 31 for PCI. E and HT were derived from in-the-field KAP measurements using Montecarlo methods.Median KAP of 23.2 and 56.8 Gy cm2 and E of 6.9 and 20.0 mSv were found for CA and PCI, respectively. Mean KAP and E were significantly higher in males than in females (52.4 ± 40.0 vs 32.3 ± 16.6 Gy cm2; p = 0.02) and (16.8 ± 13.6 vs 10.7 ± 5.8 mSv; p = 0.04). KAP (r = 0.39; p = 0.001) and E (r = 0.34; p = 0.005) showed a significant correlation with the patient’s weight.Conversion factors between KAP and E (E/KAP) were 0.30 ± 0.04 mSv Gy−1 cm−2 for CA and 0.33 ± 0.05 mSv Gy−1 cm−2 for PCI. No significant differences in the E/KAP between males and females were found (0.31 ± 0.05 vs 0.33 ± 0.05; p = 0.08). Again, no significant correlation was found between E/KAP and patient’s weight (r = 0.23; p = 0.07).The correlation between E and KAP was excellent for CA (r = 0.99) and PCI (r = 0.96). The correlation between HT and KAP ranged from r = 0.87 to r = 1 and from r = 0.71 to r = 0.98 for CA and PCI, respectively.A single factor, the total KAP, could be used for a specific acquisition protocol to reliably estimate E and HT without the need of a patient’s specific analysis. Conversion factors might be installation, X-ray beam quality or protocol dependent. 相似文献
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This paper describes issues of concern for protecting foetuses and breast-fed children of occupationally exposed women in nuclear medicine from unnecessary exposure of ionising radiation. The protection principle is to ensure the same level of protection for the foetus and child as for the general public. Therefore international radiation protection standards recommend a dose constraint of 1 mSv to a foetus during the remaining time of pregnancy after it is known/declared and a yearly dose constraint of 1 mSv to a breast-fed child. It is not self-evident how to guarantee this level of radiation protection.The exposure situation in nuclear medicine is complex. Exploring existing reported occupational exposure levels suggests great variability between work tasks and facilities. The standards and guidelines found give no detailed advice. Therefore each facility needs to systematically review external and internal exposure levels in order to plan appropriate protection measures and issue their own guidelines and rules. One strategy might be that each facility defines tasks that do not require any restrictions and lists such duties that are not suitable to do when pregnant or breastfeeding, taking also potential exposure levels into consideration. This paper gives examples of such types of work.Information to the staff about the necessity of declaring pregnancy or breastfeeding is of fundamental importance. The internal policies issued by the hospital management should make clear the basis for taking care of pregnant and breastfeeding employees. 相似文献
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PurposeThis study aimed to measure the eye lens doses received by physicians and other medical staff participating in non-vascular imaging and interventional radiology procedures in Japan.Material and methodsFrom October 2014 to March 2017, 34 physicians and 29 other medical staff engaged in non-vascular imaging and interventional radiology procedures at 18 Japanese medical facilities. These professionals wore radioprotective lead glasses equipped with small, optically stimulated luminescence dosimeters and additional personal dosimeters at the neck during a 1-month monitoring period. The Hp(3) and the Hp(10) and Hp(0.07) were obtained from these devices, respectively. The monthly Hp(3), Hp(10), and Hp(0.07) for each physician and other medical staff member were then rescaled to a 12-month period to enable comparisons with the revised occupational equivalent dose limit for the eye lens.ResultsAmong physicians, the average annual Hp(3) values measured by the small luminescence dosimeters on radioprotective glasses were 25.5 ± 38.3 mSv/y (range: 0.4–166.8 mSv/y) and 9.3 ± 16.6 mSv/y (range: 0.3–82.4 mSv/y) on the left and right sides, respectively. The corresponding values for other medical staff were 3.7 ± 3.1 mSv/y (range: 0.4–10.4 mSv/y) and 3.2 ± 2.7 mSv/y (range: 0.5–11.5 mSv/y), respectively.ConclusionsThe eye lens doses incurred by physicians and other medical staff who engaged in non-vascular imaging and interventional radiology procedures in Japan were provided. Physicians should wear radioprotective glasses and use additional radioprotective devices to reduce the amount of eye lens doses they receive. 相似文献
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目的:了解哈尔滨市某三级医院介入人员外照射个人剂量现况和本院辐射防护情况,以期为本院介入防护策略提供一定的科学依据。方法:按照《中华人民共和国国家职业卫生标准》(GBZ128-2016)版本要求,在2016年7月8号～2017年7月8号期间,采用双剂量计监测目标人群年外照射个人剂量,x2检验和logistic回归分析介入人员外照射个人剂量的影响因素。结果:年外照射最小个人剂量为0.08mSv,最大个人剂量为3.60mSv,平均个人剂量为0.23mSv,x2检验表明科室(x~2=50.420,P0.001)、职业类别(x~2=32.992,P0.001)、职称(x~2=33.806,P0.001)和学历(x2=9.289,P0.05)有统计学意义;logistic回归分析均表明,职称、工作年限、职业类别进入方程,但只有职称(Wals=4.896,P0.05)和职业类别(Wals=8.424,P0.05)有统计学意义,医务人员职称和职业类别(Wals=8.424,P0.05)是影响个人外照射剂量的因素。结论:本院总体外照射防护措施得当,本院从事介入工作的相关医务人员中,高级职称医务人员外照射个人剂量低于中、低级职称医务人员;技师外照射个人剂量高于护士和医生。根据本研究结果,在医院的外照射防护中应采取一些措施,比如合理分配工作,避免同一工种医务人员长时间暴露于介入相关外照射,避免中低级职称医生长时间接触介入相关外照射,加强医务人员防护意识,适当调整工作岗位,适时进行防护培训。 相似文献
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IntroductionSentinel node biopsy is a procedure used for axillary nodal staging in breast cancer surgery. The process uses radioactive 99mTc isotope for mapping the sentinel node(s) and all the staff involved in the procedure is potentially exposed to ionizing radiation. The colloid for radiolabelling (antimone-sulphide) with 99mTc isotope (half-life 6 h) is injected into the patient breast. The injection has activity of 18.5 MBq. The surgeon removes the primary tumor and detects active lymph nodes with gamma detection unit. The tumor as well as the active nodal tissue is transferred to pathologist for the definitive findings. The aim of the study was to measure dose equivalents to extremities and whole body for all staff and suggest practice improvement in order to minimize exposure risk.Materials and methodsThe measurements of the following operational quantities were performed: Hp(10) personal dose equivalent to whole body and Hp(0.07) to extremities for staff as well as ambiental dose for operating theatre and during injection.Hp(0.07) were measured at surgeon’s finger by ring thermoluminescent dosimeter (TLD) type MTS-N, and reader RADOS RE2000. Surgeon and nurse were wearing TLD personal dosimeter at the chest level. Anesthesiologist and anesthetist were wearing electronic personal dosimeters, while pathologist was wearing ring TLD while manipulating tissue samples.Electronic dosimeters used were manufactured by Polimaster, type PM1610.All TLD and electronic dosimeters data were reported, including background radiation. Background radiation was also monitored separately. Personal TLDs are standard for this type of personal monitoring, provided by accredited laboratory.Measurements of ambiental dose in workplaces of other staff involved around the patient was performed before the surgery took place, by calibrated survey meters manufactured by Atomtex, type 1667.The study involved two surgeons and one pathologist, two anesthesiologists and three anesthetists during two months period.Results and discussionThe doses received by all staff are evaluated using passive and active personal dosimeters and ambiental dose monitors and practice was improved based on results collected. Average annual whole body dose for all staff involved in the procedure was less than 0.8 mSv. Extremity dose equivalents to surgeon and pathologist were far below the limits set for professionally exposed (surgeon) and for public (pathologist).ConclusionsAlthough has proven to be very safe for all staff, additional measures for radiation protection, in accordance to ALARA principle (As Low As Reasonably Achievable) should be conducted. The recommendations for practice improvement with respect to radiation protection were issued. 相似文献
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V. Riethmeister U. Bültmann M.R. De Boer M. Gordijn S. Brouwer 《Chronobiology international》2018,35(6):759-772
ABSTRACTTo better understand sleep quality and sleepiness problems offshore, we examined courses of sleep quality and sleepiness in full 2-weeks on/2-weeks off offshore day shift rotations by comparing pre-offshore (1 week), offshore (2 weeks) and post-offshore (1 week) work periods. A longitudinal observational study was conducted among N=42 offshore workers. Sleep quality was measured subjectively with two daily questions and objectively with actigraphy, measuring: time in bed (TIB), total sleep time (TST), sleep latency (SL) and sleep efficiency percentage (SE%). Sleepiness was measured twice a day (morning and evening) with the Karolinska Sleepiness Scale. Changes in sleep and sleepiness parameters during the pre/post and offshore work periods were investigated using (generalized) linear mixed models. In the pre-offshore work period, courses of SE% significantly decreased (p=.038). During offshore work periods, the courses of evening sleepiness scores significantly increased (p<.001) and significantly decreased during post-offshore work periods (p=.004). During offshore work periods, TIB (p<.001) and TST (p<.001) were significantly shorter, SE% was significantly higher (p=.002), perceived sleep quality was significantly lower (p<.001) and level of rest after wake was significantly worse (p<.001) than during the pre- and post-offshore work periods. Morning sleepiness was significantly higher during offshore work periods (p=.015) and evening sleepiness was significantly higher in the post-offshore work period (p=.005) compared to the other periods. No significant changes in SL were observed. Courses of sleep quality and sleepiness parameters significantly changed during full 2-weeks on/2-weeks off offshore day shift rotation periods. These changes should be considered in offshore fatigue risk management programmes. 相似文献
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Paediatric patients with non-oncologic chronic illnesses often require ongoing care that may result in repeated imaging and exposure to ionizing radiation from both diagnostic and interventional procedures. In this study the scientific literature on cumulative effective dose (CED) of radiation accrued from medical imaging among specific cohorts of paediatric, non-oncologic chronic patients (inflammatory bowel disease, cystic fibrosis, congenital heart disease, shunt-treated hydrocephalus, hemophilia, spinal dysraphism) was systematically reviewed.We conducted PubMed/Medline, Scopus and EMBASE searches of peer-reviewed papers on CED from diagnostic and therapeutic radiological examinations. No time restriction was introduced in the search. Only studies reporting CEDs accrued for a period >1 year were included.We found that the annual CED was relatively low (<3 mSv/year) in cystic fibrosis, congenital heart disease, patients with cerebrospinal fluid shunts and hemophilia, while being moderate (>3–20 mSv/year) in Crohn's patients.This extra yearly radiation exposure accrues over the lifetime and can reach high values (>100 mSv) in selected cohorts of paediatric chronic patients. 相似文献
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PurposeIn interventional cardiology, patients may be exposed to high doses to the skin resulting in skin burns following single or multiple procedures. Reviewing and analysing available software (online or offline) may help medical physicists assessing the maximum skin dose to the patient together with the dose distribution during (or after) these procedures.Method and resultsCapabilities and accuracy of available software were analysed through an extensive bibliography search and contacts with both vendor and authors. Their markedly differed among developers.In total, 22 software were identified and reviewed according to their algorithms and their capabilities. Special attention was dedicated to their main features and limitations of interest for the intended clinical use.While the accuracy of the 12 software products validated with measurements on phantoms was acceptable (within ± 25%), the agreement was poor for the two products validated on patients (within ± 43% and ± 76%, respectively). In addition, no software has been validated on angiographic units from all manufacturers, though several software developers claimed vendor-independent transportability. Only one software allows for multiple procedures dose calculation.ConclusionLarge differences among vendors made it clear that work remains to be done before an accurate and reliable skin dose mapping is available for all patients. 相似文献
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The aim of this work was to create a model of a wide-bore Siemens Somatom Sensation Open CT scanner for use with GMCTdospp, which is an EGSnrc-based software tool dedicated for Monte Carlo calculations of dose in CT examinations.The method was based on matching spectrum and filtration to half value layer and dose profile, and thus was similar to the method of Turner et al. (Med. Phys. 36, pp. 2154–2164). Input data on unfiltered beam spectra were taken from two sources: the TASMIP model and IPEM Report 78. Two sources of HVL data were also used, namely measurements and documentation. Dose profile along the fan-beam was measured with Gafchromic RTQA-1010 (QA+) film. Two-component model of filtration was assumed: bow-tie filter made of aluminum with 0.5 mm thickness on central axis, and flat filter made of one of four materials: aluminum, graphite, lead, or titanium.Good agreement between calculations and measurements was obtained for models based on the measured values of HVL. Doses calculated with GMCTdospp differed from the doses measured with pencil ion chamber placed in PMMA phantom by less than 5%, and root mean square difference for four tube potentials and three positions in the phantom did not exceed 2.5%. The differences for models based on HVL values from documentation exceeded 10%. Models based on TASMIP spectra and IPEM78 spectra performed equally well. 相似文献
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The appearance of a malignant disease during pregnancy is relatively rare. The use of external-beam radiation therapy is limited to non-pelvic tumors which are usually located above the diaphragm. However, supradiaphragmatic radiotherapy unavoidably exposes the fetus to secondary radiation due to head leakage, scatter from the machine and scatter produced inside the patient. This fetal exposure may be associated with an elevated risk for the development of deterministic harmful effects and/or carcinogenesis. The decision about the administration of radiotherapy in a pregnant patient is influenced by the fetal dose which must always be estimated before the patient’s treatment course. The methods employed for fetal dosimetry in external-beam radiotherapy are described in this review study. Direct dose measurements using thermoluminescent dosemeters or large ionization chambers placed on physical phantoms may be used. Monte Carlo simulations on computational phantoms may also provide accurate fetal dose calculations. The physical and/or computational phantoms need to simulate the full-scatter geometry of the pregnant patient. Typical fetal dose values attributable to radiation therapy for brain tumors, head and neck cancer, breast carcinoma and Hodgkin lymphoma at the first, second and third trimesters of gestation are presented. The effectiveness of different shielding devices for fetal dose reduction in radiotherapy is discussed. The effect of the dimensions and setup of the shielding material on the radiation dose received by the fetus is described. Moreover, practical methods for reducing the fetal dose by selecting the appropriate irradiation parameters are presented. 相似文献
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This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 125I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total dose at analytical calculation point. Some brachytherapy seeds contain multi-radioactive elements so the dose at any point is a total of separate doses from each element. It is momentous to know well the angular and radial dose distributions around the source that is located in cancerous tissue for clinical treatments. Interior geometry of a source is effective on dose characteristics of a distribution. Dose information of inner geometrical structure of a brachytherapy source cannot be acquired by experimental methods because of limits of physical material and geometry in the healthy tissue, so Monte Carlo simulation is a required approach of the study. EGSnrc Monte Carlo simulation software was used. In the design of a simulation, the radioactive source was divided into 10 rings, partitioned but not separate from each other. All differential sources were simulated for dose calculation, and the shape of dose distribution was determined comparatively distribution of a single-complete source. In this work anisotropy function was examined also mathematically. 相似文献
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《Chronobiology international》2013,30(5):531-536
This dedicated issue of Chronobiology International is devoted to the selected proceedings of the 20th International Symposium on Shift Work and Working Time held in Stockholm, Sweden, 28 June to 1 July 2011. It constitutes the fifth such issue of the journal since 2004 dedicated to the selected proceedings to the meetings of the Working Time Society. The key theme of the 20th Symposium was “Biological Mechanisms, Recovery, and Risk Management in the 24-h Society.” The collection of papers of this dedicated issue represents the best of contemporary research on the effects of night and rotating shift schedules on worker health and safety. The contents cover such topics as sleep restriction, injuries, health, and performance of night work and rotating shiftwork, plus light treatment as a countermeasure against the circadian disruption of shiftwork. The majority of the papers are observational field studies, including some of large sample size, and three studies are well-designed laboratory experiments. (Author correspondence: goran.
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目的：探讨唐古特大黄多糖组分1（RTP1）对急性电离辐射损伤小鼠的保护作用。方法：采用昆明种小鼠,随机分为5组：正常对照组（Normal Control,NC）、辐射对照组（Irradiation Control,IC）以及RTP1低剂量组（200 mg/kg）、中（400 mg/kg）和高剂量组（800 mg/kg）,采用灌胃给药方式,连续14 d,NC组和IC组则给予等量的生理盐水,第14 d除NC组外,各组小鼠均接受2.0 Gy/只60Coγ射线照射1次,照射后24 h,检测小鼠胸腺和脾脏指数,测定肝脏超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-Px）活性及丙二酰二醛（MDA）水平以及小鼠外周血象和骨髓嗜多染红细胞（PCE）微核数。结果：RTP1能够升高小鼠的胸腺、脾脏指数,增加肝脏SOD和GSH-Px活性,降低MDA水平,升高外周血中白细胞数并降低骨髓PCE微核数,与IC组比较有统计学意义（P〈0.05或P〈0.01）。结论：RTP1对辐射所致的小鼠损伤具有一定的保护作用。 相似文献