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Gimbert M, Doyen M, Weber N, Delmas A, Vignaud A, Fabre I, Ginisty C, Lecomte Y, Berland V, Becuwe Desmidt S, Roger S, Felblinger J. Évaluation de l’exposition au champ magnétique statique des manipulateurs en électroradiologie médicale d’un centre de recherche travaillant à proximité d’IRM 3T et 7T à l’aide d’un dispositif portable. ARCH MAL PROF ENVIRO 2023. [DOI: 10.1016/j.admp.2022.101702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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2
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Hartwig V, Virgili G, Mattei FE, Biagini C, Romeo S, Zeni O, Scarfì MR, Massa R, Campanella F, Landini L, Gobba F, Modenese A, Giovannetti G. Occupational exposure to electromagnetic fields in magnetic resonance environment: an update on regulation, exposure assessment techniques, health risk evaluation, and surveillance. Med Biol Eng Comput 2021; 60:297-320. [PMID: 34586563 DOI: 10.1007/s11517-021-02435-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 08/27/2021] [Indexed: 12/15/2022]
Abstract
Magnetic resonance imaging (MRI) is one of the most-used diagnostic imaging methods worldwide. There are ∼50,000 MRI scanners worldwide each of which involves a minimum of five workers from different disciplines who spend their working days around MRI scanners. This review analyzes the state of the art of literature about the several aspects of the occupational exposure to electromagnetic fields (EMF) in MRI: regulations, literature studies on biological effects, and health surveillance are addressed here in detail, along with a summary of the main approaches for exposure assessment. The original research papers published from 2013 to 2021 in international peer-reviewed journals, in the English language, are analyzed, together with documents published by legislative bodies. The key points for each topic are identified and described together with useful tips for precise safeguarding of MRI operators, in terms of exposure assessment, studies on biological effects, and health surveillance.
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Affiliation(s)
- Valentina Hartwig
- Institute of Clinical Physiology (IFC), Italian National Research Council (CNR), Via G. Moruzzi 1, 56124, Pisa, San Cataldo, Italy.
| | - Giorgio Virgili
- Virgili Giorgio, Via G. Pastore 2, 26040, Crespina-Lorenzana, Italy
| | - F Ederica Mattei
- West Systems S.R.L, Via Don Mazzolari 25, 56025, Pontedera, PI, Italy
| | - Cristiano Biagini
- Associazione Italiana Tecnici Dell'Imaging in Risonanza Magnetica, AITIRM, Via XX Settembre 76, 50129, Florence, Italy
| | - Stefania Romeo
- Institute for Electromagnetic Sensing of the Environment (IREA) , Italian National Research Council (CNR), Via Diocleziano 328, 80124, Naples, Italy
| | - Olga Zeni
- Institute for Electromagnetic Sensing of the Environment (IREA) , Italian National Research Council (CNR), Via Diocleziano 328, 80124, Naples, Italy
| | - Maria Rosaria Scarfì
- Institute for Electromagnetic Sensing of the Environment (IREA) , Italian National Research Council (CNR), Via Diocleziano 328, 80124, Naples, Italy
| | - Rita Massa
- Institute for Electromagnetic Sensing of the Environment (IREA) , Italian National Research Council (CNR), Via Diocleziano 328, 80124, Naples, Italy.,Department of Physics, University Federico II, Via Cinthia 21, 80126, Naples, Italy
| | - Francesco Campanella
- Dipartimento di medicina, epidemiologia, Igiene del Lavoro E Ambientale, Inail, Via Fontana Candida 1, 00078 Monte Porzio Catone, Rome, Italy
| | - Luigi Landini
- Fondazione Toscana "G. Monasterio", Via G. Moruzzi 1, 56124, Pisa, San Cataldo, Italy
| | - Fabriziomaria Gobba
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125, Modena, Italy
| | - Alberto Modenese
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125, Modena, Italy
| | - Giulio Giovannetti
- Institute of Clinical Physiology (IFC), Italian National Research Council (CNR), Via G. Moruzzi 1, 56124, Pisa, San Cataldo, Italy
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3
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Exposure levels of radiofrequency magnetic fields and static magnetic fields in 1.5 and 3.0 T MRI units. SN APPLIED SCIENCES 2021. [DOI: 10.1007/s42452-021-04178-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
AbstractMagnetic resonance imaging (MRI) staff is exposed to a complex mixture of electromagnetic fields from MRI units. Exposure to these fields results in the development of transient exposure-related symptoms. This study aimed to investigate the exposure levels of radiofrequency (RF) magnetic fields and static magnetic fields (SMFs) from 1.5 and 3.0 T MRI scanners in two public hospitals in the Mangaung Metropolitan region, South Africa. The exposure levels of SMFs and RF magnetic fields were measured using the THM1176 3-Axis hall magnetometer and TM-196 3 Axis RF field strength meter, respectively. Measurements were collected at a distance of 1 m (m) and 2 m from the gantry for SMFs when the brain, cervical spine and extremities were scanned. Measurements for RF magnetic fields were collected at a distance of 1 m with an average scan duration of six minutes. Friedman’s test was used to compared exposure mean values from two 1.5 T scanners, and Wilcoxon test with Bonferroni adjustment was used to identify where the difference between exist. The Shapiro–Wilk test was also used to test for normality between exposure levels in 1.5 and 3.0 T scanners. The measured peak values for SMFs from the 3.0 T scanner at hospital A were 1300 milliTesla (mT) and 726 mT from 1.5 T scanner in hospital B. The difference in terms of SMFs exposure levels was observed between two 1.5 T scanners at a distance of 2 m. The difference between 1.5 T scanners at 1 m was also observed during repeated measurements when brain, cervical spine and extremities scans were performed. Scanners’ configurations, magnet type, clinical setting and location were identified as factors that could influence different propagation of SMFs between scanners of the same nominal B0. The RF pulse design, sequence setting flip-angle and scans performed influenced the measured RF magnetic fields. Three scanners were complaint with occupational exposure guidelines stipulated by the ICNIRP; however, peak levels that exist at 1 m could be managed through adoption of occupational health and safety programs.
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4
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Hartwig V, Biagini C, De Marchi D, Flori A, Gabellieri C, Virgili G, Ferrante Vero LF, Landini L, Vanello N, Giovannetti G. Analysis, comparison and representation of occupational exposure to a static magnetic field in a 3-T MRI site. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2020; 28:76-85. [PMID: 32276568 DOI: 10.1080/10803548.2020.1738114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The purpose of this study is to analyze exposure to the time-varying magnetic field caused by worker movements in a 3-T clinical magnetic resonance imaging (MRI) scanner. Measurements of the static magnetic field (B) in the proximity of the MRI scanner were performed to create a detailed map of the spatial gradient of B, in order to indicate the areas at high risk of exposure. Moreover, a personal exposure recording system was used in order to analyze and compare exposure to the static magnetic field during different routine procedures in MRI. We found that for all of the performed work activities, exposure was compliant with International Commission on Non-Ionizing Radiation Protection levels. However, our findings confirm that there is great variability of exposure between different workers and suggest the importance of performing personal exposure measurements and of detailed knowledge of the magnetic field spatial distribution.
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Affiliation(s)
| | - Cristiano Biagini
- Associazione Italiana Tecnici dell'Imaging in Risonanza Magnetica, AITIRM, Italy
| | - Daniele De Marchi
- Associazione Italiana Tecnici dell'Imaging in Risonanza Magnetica, AITIRM, Italy.,Fondazione CNR-Regione Toscana 'G. Monasterio', Italy
| | | | | | | | | | - Luigi Landini
- Fondazione CNR-Regione Toscana 'G. Monasterio', Italy.,Department of Information Engineering, University of Pisa, Italy
| | - Nicola Vanello
- Department of Information Engineering, University of Pisa, Italy
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5
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Ghadimi-Moghadam A, Mortazavi SMJ, Hosseini-Moghadam A, Haghani M, Taeb S, Hosseini MA, Rastegariyan N, Arian F, Sanipour L, Aghajari S, Mortazavi SAR, Soofi A, Dizavandi MR. Does Exposure to Static Magnetic Fields Generated by Magnetic Resonance Imaging Scanners Raise Safety Problems for Personnel? J Biomed Phys Eng 2018; 8:333-336. [PMID: 30320037 PMCID: PMC6169123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 11/08/2015] [Indexed: 05/12/2023]
Abstract
MRI workers are occupationally exposed to static and time-varying gradient magnetic fields. While the 24-hour time-averaged exposure to static magnetic fields is about a few mT, the maximum static field strength can be as high as 500 mT during patient setup. Over the past several years, our laboratory has performed extensive experiments on the health effects of exposure of animal models and humans to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. This study is to investigate the adverse health effects in MRI workers and also to assess the effect of exposure of MRI workers to static magnetic fields on their cognitive functions. In the first phase of this study a questionnaire was designed to collect information from 120 MRI personnel. The collection of data about the adverse health effects was based on self-reporting by the participants. In the second phase, 47 volunteer university students were asked to continuously move around a 1.5 T MRI scanner. Visual reaction time and working memory tests were performed on all participants before and after the experiment. Forward digit span and backward digit span were used for assessing the working memory. Furthermore, participants were asked to report the symptoms they had experienced during the movement. The first phase of our study showed increased frequencies of adverse health effects in MRI workers. In this study the rates of self-reported symptoms such as a headache, sleep problems, myalgia, palpitation, fatigue, concentration problems, attention problems, nervousness and backpain were possibly affected by static magnetic field. Furthermore we found that reaction time and working memory could be influenced by the movements of the body around a MRI scanner. It can be concluded that movement through a high magnetic field can also lead to some adverse cognitive effects in MRI staff.
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Affiliation(s)
- A Ghadimi-Moghadam
- Pediatric Infectious Ward, Yasuj University of Medical Sciences, Yasuj, Iran
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - S M J Mortazavi
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
- Medical Physics and Medical Engineering Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - A Hosseini-Moghadam
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Haghani
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - S Taeb
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - M A Hosseini
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Rastegariyan
- Speech and Language Pathology Department, School of Rehabilitation, Shiraz University of Medical Sciences, Shiraz, Iran
| | - F Arian
- M.Sc Student in Radiobiology and Protection, Paramedical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - L Sanipour
- M.Sc Student in Radiobiology and Protection, Paramedical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S Aghajari
- M.Sc Student in Radiobiology and Protection, Paramedical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S A R Mortazavi
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - A Soofi
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - M R Dizavandi
- MRI Department, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
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6
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Frankel J, Wilén J, Hansson Mild K. Assessing Exposures to Magnetic Resonance Imaging's Complex Mixture of Magnetic Fields for In Vivo, In Vitro, and Epidemiologic Studies of Health Effects for Staff and Patients. Front Public Health 2018; 6:66. [PMID: 29594090 PMCID: PMC5858533 DOI: 10.3389/fpubh.2018.00066] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 02/19/2018] [Indexed: 12/15/2022] Open
Abstract
A complex mixture of electromagnetic fields is used in magnetic resonance imaging (MRI): static, low-frequency, and radio frequency magnetic fields. Commonly, the static magnetic field ranges from one to three Tesla. The low-frequency field can reach several millitesla and with a time derivative of the order of some Tesla per second. The radiofrequency (RF) field has a magnitude in the microtesla range giving rise to specific absorption rate values of a few Watts per kilogram. Very little attention has been paid to the case where there is a combined exposure to several different fields at the same time. Some studies have shown genotoxic effects in cells after exposure to an MRI scan while others have not demonstrated any effects. A typical MRI exam includes muliple imaging sequences of varying length and intensity, to produce different types of images. Each sequence is designed with a particular purpose in mind, so one sequence can, for example, be optimized for clearly showing fat water contrast, while another is optimized for high-resolution detail. It is of the utmost importance that future experimental studies give a thorough description of the exposure they are using, and not just a statement such as “An ordinary MRI sequence was used.” Even if the sequence is specified, it can differ substantially between manufacturers on, e.g., RF pulse height, width, and duty cycle. In the latest SCENIHR opinion, it is stated that there is very little information regarding the health effects of occupational exposure to MRI fields, and long-term prospective or retrospective cohort studies on workers are recommended as a high priority. They also state that MRI is increasingly used in pediatric diagnostic imaging, and a cohort study into the effects of MRI exposure on children is recommended as a high priority. For the exposure assessment in epidemiological studies, there is a clear difference between patients and staff and further work is needed on this. Studies that explore the possible differences between MRI scan sequences and compare them in terms of exposure level are warranted.
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Affiliation(s)
- Jennifer Frankel
- Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå, Sweden
| | - Jonna Wilén
- Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå, Sweden
| | - Kjell Hansson Mild
- Department of Radiation Sciences, Radiation Physics, Umeå University, Umeå, Sweden
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7
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Kim SJ, Kim KA. Safety issues and updates under MR environments. Eur J Radiol 2017; 89:7-13. [PMID: 28267552 DOI: 10.1016/j.ejrad.2017.01.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 01/11/2017] [Accepted: 01/13/2017] [Indexed: 11/18/2022]
Abstract
Magnetic resonance (MR) imaging is a useful imaging tool with superior soft tissue contrast for diagnostic evaluation. The MR environments poses unique risks to patients and employees differently from ionizing radiation exposure originated from computed tomography and plain x-ray films. The technology associated with MR system has evolved continuously since its introduction in the late 1970s. MR systems have advanced with static magnetic fields, faster and stronger gradient magnetic fields and more powerful radiofrequency transmission coils. Higher field strengths of MR offers greater signal to noise capability and better spatial resolution, resulting in better visualization of anatomic detail, with a reduction in scan time. With the rapid evolution of technology associated with MR, we encounter new MR-related circumstances and unexpected dangerous conditions. A comprehensive update of our knowledge about MR safety is necessary to prevent MR-related accidents and to ensure safety for patients and staff associated with MR. This review presents an overview about MR-related safety issues and updates.
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Affiliation(s)
- Soo Jung Kim
- Department of Radiology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kyung Ah Kim
- Department of Radiology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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8
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Iachininoto MG, Camisa V, Leone L, Pinto R, Lopresto V, Merla C, Giorda E, Carsetti R, Zaffina S, Podda MV, Teofili L, Grassi C. Effects of exposure to gradient magnetic fields emitted by nuclear magnetic resonance devices on clonogenic potential and proliferation of human hematopoietic stem cells. Bioelectromagnetics 2016; 37:201-11. [PMID: 26992028 DOI: 10.1002/bem.21967] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 02/26/2016] [Indexed: 01/29/2023]
Abstract
This study investigates effects of gradient magnetic fields (GMFs) emitted by magnetic resonance imaging (MRI) devices on hematopoietic stem cells. Field measurements were performed to assess exposure to GMFs of staff working at 1.5 T and 3 T MRI units. Then an exposure system reproducing measured signals was realized to expose in vitro CD34+ cells to GMFs (1.5 T-protocol and 3 T-protocol). CD34+ cells were obtained by Fluorescence Activated Cell Sorting from six blood donors and three MRI-exposed workers. Blood donor CD34+ cells were exposed in vitro for 72 h to 1.5 T or 3 T-protocol and to sham procedure. Cells were then cultured and evaluated in colony forming unit (CFU)-assay up to 4 weeks after exposure. Results showed that in vitro GMF exposure did not affect cell proliferation but instead induced expansion of erythroid and monocytes progenitors soon after exposure and for the subsequent 3 weeks. No decrease of other clonogenic cell output (i.e., CFU-granulocyte/erythroid/macrophage/megakaryocyte and CFU-granulocyte/macrophage) was noticed, nor exposed CD34+ cells underwent the premature exhaustion of their clonogenic potential compared to sham-exposed controls. On the other hand, pilot experiments showed that CD34+ cells exposed in vivo to GMFs (i.e., samples from MRI workers) behaved in culture similarly to sham-exposed CD34+ cells, suggesting that other cells and/or microenvironment factors might prevent GMF effects on hematopoietic stem cells in vivo. Accordingly, GMFs did not affect the clonogenic potential of umbilical cord blood CD34+ cells exposed in vitro together with the whole mononuclear cell fraction.
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Affiliation(s)
| | - Vincenzo Camisa
- Occupational Medicine/Health Technology Assessment and Safety Research Unit, Clinical-Technological Innovations Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Lucia Leone
- Institute of Human Physiology, Università Cattolica, Rome, Italy
| | - Rosanna Pinto
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Vanni Lopresto
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Caterina Merla
- ENEA, Italian Agency for New Technologies, Energy, and Sustainable Economic Development, Division of Health Protection Technologies, Casaccia Research Centre, Rome, Italy
| | - Ezio Giorda
- Immunology Unit, Immunology and Pharmacotherapy Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Rita Carsetti
- Immunology Unit, Immunology and Pharmacotherapy Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Salvatore Zaffina
- Occupational Medicine/Health Technology Assessment and Safety Research Unit, Clinical-Technological Innovations Research Area-Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | | | - Luciana Teofili
- Department of Transfusion Medicine, Institute of Hematology, Università Cattolica, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica, Rome, Italy.,San Raffaele Pisana Scientific Institute for Research, Hospitalization and Health Care, Rome, Italy
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9
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Abstract
Magnetic resonance imaging (MRI) has a superior soft-tissue contrast compared to other radiological imaging modalities and its physiological and functional applications have led to a significant increase in MRI scans worldwide. A comprehensive MRI safety training to protect patients and other healthcare workers from potential bio-effects and risks of the magnetic fields in an MRI suite is therefore essential. The knowledge of the purpose of safety zones in an MRI suite as well as MRI appropriateness criteria is important for all healthcare professionals who will work in the MRI environment or refer patients for MRI scans. The purpose of this article is to give an overview of current magnetic resonance safety guidelines and discuss the safety risks of magnetic fields in an MRI suite including forces and torque of ferromagnetic objects, tissue heating, peripheral nerve stimulation, and hearing damages. MRI safety and compatibility of implanted devices, MRI scans during pregnancy, and the potential risks of MRI contrast agents will also be discussed, and a comprehensive MRI safety training to avoid fatal accidents in an MRI suite will be presented.
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Affiliation(s)
- Steffen Sammet
- Department of Radiology, University of Chicago Medicine, 5841 South Maryland Avenue, MC2026, Chicago, IL, 60637, USA.
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10
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Subjective perception of safety in healthy individuals working with 7 T MRI scanners: a retrospective multicenter survey. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2016; 29:379-87. [DOI: 10.1007/s10334-016-0527-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 10/22/2022]
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11
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Batistatou E, Mölter A, Kromhout H, van Tongeren M, Crozier S, Schaap K, Gowland P, Keevil SF, de Vocht F. Personal exposure to static and time-varying magnetic fields during MRI procedures in clinical practice in the UK. Occup Environ Med 2015; 73:779-786. [PMID: 26675205 PMCID: PMC5116531 DOI: 10.1136/oemed-2015-103194] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/28/2015] [Indexed: 11/07/2022]
Abstract
Background MRI has developed into one of the most important medical diagnostic imaging modalities, but it exposes staff to static magnetic fields (SMF) when present in the vicinity of the MR system, and to radiofrequency and switched gradient electromagnetic fields if they are present during image acquisition. We measured exposure to SMF and motion-induced time-varying magnetic fields (TVMF) in MRI staff in clinical practice in the UK to enable extensive assessment of personal exposure levels and variability, which enables comparison to other countries. Methods 8 MRI facilities across National Health Service sites in England, Wales and Scotland were included, and staff randomly selected during the days when measurements were performed were invited to wear a personal MRI-compatible dosimeter and keep a diary to record all procedures and tasks performed during the measured shift. Results 98 participants, primarily radiographers (71%) but also other healthcare staff, anaesthetists and other medical staff were included, resulting in 149 measurements. Average geometric mean peak SMF and TVMF exposures were 448 mT (range 20–2891) and 1083 mT/s (9–12 355 mT/s), and were highest for radiographers (GM=559 mT and GM=734 mT/s). Time-weighted exposures to SMF and TVMF (GM=16 mT (range 5–64) and GM=14 mT/s (range 9–105)) and exposed-time-weighted exposures to SMF and TVMF (GM=27 mT (range 11–89) and GM=17 mT/s (range 9–124)) were overall relative low—primarily because staff were not in the MRI suite for most of their shifts—and did not differ significantly between occupations. Conclusions These results are comparable to the few data available from the UK but they differ from recent data collected in the Netherlands, indicating that UK staff are exposed for shorter periods but to higher levels. These data indicate that exposure to SMF and TVMF from MRI scanners cannot be extrapolated across countries.
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Affiliation(s)
- Evridiki Batistatou
- Centre for Occupational and Environmental Health, University of Manchester, Manchester, UK
| | - Anna Mölter
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Hans Kromhout
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, The Netherlands
| | - Martie van Tongeren
- Centre for Human Exposure Science, Institute of Occupational Medicine, Edinburgh, UK
| | - Stuart Crozier
- School of Information Technology and Electrical Engineering, University of Queensland, Brisbane, Queensland, Australia
| | - Kristel Schaap
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, The Netherlands
| | - Penny Gowland
- School of Physics and Astronomy, The University of Nottingham, Nottingham, UK
| | - Stephen F Keevil
- Department of Medical Physics, Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Biomedical Engineering, King's College London, London, UK
| | - Frank de Vocht
- School of Social and Community Medicine, University of Bristol, Bristol, UK
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12
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Sammet S, Sammet CL. Implementation of a comprehensive MR safety course for medical students. J Magn Reson Imaging 2015; 42:1478-86. [PMID: 26172156 PMCID: PMC4713360 DOI: 10.1002/jmri.24993] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 06/18/2015] [Accepted: 06/22/2015] [Indexed: 11/07/2022] Open
Abstract
This review article proposes the design of an educational magnetic resonance (MR) safety course for instructing medical students about basic MR and patient-related safety. The MR safety course material can be implemented as a traditional didactic or interactive lecture in combination with hands-on safety demonstrations. The goal of the course is to ensure that medical students receive a basic understanding of MR principles and safety considerations. This course will prepare medical students for patient screening and safety consultations when ordering MR studies. A multiple-choice exam can be used to document the proficiency in MR safety of the medical students. The course can be used by various medical school programs and may help to ensure consistent quality of teaching materials and MR safety standards.
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Affiliation(s)
| | - Christina L. Sammet
- Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL
- Northwestern University, Chicago, IL
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13
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Misa-Agustiño MJ, Jorge-Mora T, Jorge-Barreiro FJ, Suarez-Quintanilla J, Moreno-Piquero E, Ares-Pena FJ, López-Martín E. Exposure to non-ionizing radiation provokes changes in rat thyroid morphology and expression of HSP-90. Exp Biol Med (Maywood) 2015; 240:1123-35. [PMID: 25649190 DOI: 10.1177/1535370214567611] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 11/21/2014] [Indexed: 11/15/2022] Open
Abstract
Non-ionizing radiation at 2.45 GHz may modify the morphology and expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Diathermy is the therapeutic application of non-ionizing radiation to humans for its beneficial effects in rheumatological and musculo-skeletal pain processes. We used a diathermy model on laboratory rats subjected to maximum exposure in the left front leg, in order to study the effects of radiation on the nearby thyroid tissue. Fifty-six rats were individually exposed once or repeatedly (10 times in two weeks) for 30 min to 2.45 GHz radiation in a commercial chamber at different non-thermal specific absorption rates (SARs), which were calculated using the finite difference time domain technique. We used immunohistochemistry methods to study the expression of HSP-90 and morphological changes in thyroid gland tissues. Ninety minutes after radiation with the highest SAR, the central and peripheral follicles presented increased size and the thickness of the peripheral septa had decreased. Twenty-four hours after radiation, only peripheral follicles radiated at 12 W were found to be smaller. Peripheral follicles increased in size with repeated exposure at 3 W power. Morphological changes in the thyroid tissue may indicate a glandular response to acute or repeated stress from radiation in the hypothalamic-pituitary-thyroid axis. Further research is needed to determine if the effect of this physical agent over time may cause disease in the human thyroid gland.
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Affiliation(s)
- Maria J Misa-Agustiño
- Morphological Sciences Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Teresa Jorge-Mora
- Morphological Sciences Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Francisco J Jorge-Barreiro
- Morphological Sciences Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Juan Suarez-Quintanilla
- Morphological Sciences Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Eduardo Moreno-Piquero
- Applied Physics Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Francisco J Ares-Pena
- Applied Physics Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Elena López-Martín
- Morphological Sciences Department, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
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14
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Karpowicz J, Gryz K. The pattern of exposure to static magnetic field of nurses involved in activities related to contrast administration into patients diagnosed in 1.5 T MRI scanners. Electromagn Biol Med 2014; 32:182-91. [PMID: 23675621 DOI: 10.3109/15368378.2013.776428] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Static magnetic fields (SMFs) and time-varying electromagnetic fields exposure is necessary to obtain the diagnostic information regarding the structure of patient's tissues, by the use of magnetic resonance imaging (MRI) scanners. A diagnostic procedure may also include the administration of pharmaceuticals called contrast, which are to be applied to a patient during the examination. The nurses involved in administering contrast into a patient during the pause in examination are approaching permanently active magnets of MRI scanners and are exposed to SMF. There were performed measurements of spatial distribution of SMF in the vicinity of MRI magnets and parameters of personal exposure of nurses (i.e. individual exposimetric profiles of variability in time of SMF affecting the nurse who is performing tasks in the vicinity of magnet, characterized by statistical parameters of recorded magnetic flux density affecting the nurse). The SMF exposure in the vicinity of various MRI magnets depends on both magnetic flux density of the main field B 0 (applicable to a patient) and the construction of the scanner, but the most important factor determining the workers' exposure is the work practice. In the course of a patient's routine examination in scanners of B₀ = 1.5 T, the nurses are present over ∼0.4-2.9 min in SMF exceeding 0.03% of B₀ (i.e. 0.5 mT), but only sometimes they are present in SMF exceeding 5% of B 0 (i.e. 75 mT). When patients need more attention because of their health status/condition, the nurses' exposure may be significantly longer--it may even exceed 10 min and 30% of B 0 (i.e. 500 mT). We have found that the level of exposure of nurses to SMF may vary from < 5% of the main field (a median value: 0.5-1.5%; inter-quartile range: 0.04-8.8%; max value: 1.3-12% of B₀) when a patient is moved from the magnets bore before contrast administration, up to the main field level (B₀) when a patient stays in the magnets bore and nurse is crawling into the bore.
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Affiliation(s)
- Jolanta Karpowicz
- Laboratory of Electromagnetic Hazards, Central Institute for Labour Protection-National Research Institute-CIOP-PIB, Warszawa, Poland.
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15
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Gherardini L, Ciuti G, Tognarelli S, Cinti C. Searching for the perfect wave: the effect of radiofrequency electromagnetic fields on cells. Int J Mol Sci 2014; 15:5366-87. [PMID: 24681584 PMCID: PMC4013569 DOI: 10.3390/ijms15045366] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/17/2014] [Accepted: 03/20/2014] [Indexed: 12/23/2022] Open
Abstract
There is a growing concern in the population about the effects that environmental exposure to any source of “uncontrolled” radiation may have on public health. Anxiety arises from the controversial knowledge about the effect of electromagnetic field (EMF) exposure to cells and organisms but most of all concerning the possible causal relation to human diseases. Here we reviewed those in vitro and in vivo and epidemiological works that gave a new insight about the effect of radio frequency (RF) exposure, relating to intracellular molecular pathways that lead to biological and functional outcomes. It appears that a thorough application of standardized protocols is the key to reliable data acquisition and interpretation that could contribute a clearer picture for scientists and lay public. Moreover, specific tuning of experimental and clinical RF exposure might lead to beneficial health effects.
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Affiliation(s)
- Lisa Gherardini
- Institute of Clinical Physiology, Consiglio Nazionale delle Ricerche Siena, Strada Petriccio e Belriguardo, Siena 53100, Italy.
| | - Gastone Ciuti
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggio 34, Pisa 56025, Italy.
| | - Selene Tognarelli
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggio 34, Pisa 56025, Italy.
| | - Caterina Cinti
- Institute of Clinical Physiology, Consiglio Nazionale delle Ricerche Siena, Strada Petriccio e Belriguardo, Siena 53100, Italy.
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16
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Yamaguchi-Sekino S, Nakai T, Imai S, Izawa S, Okuno T. Occupational exposure levels of static magnetic field during routine MRI examination in 3T MR system. Bioelectromagnetics 2013; 35:70-5. [PMID: 24115150 DOI: 10.1002/bem.21817] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 08/28/2013] [Indexed: 11/08/2022]
Abstract
Occupational exposure to the high static magnetic fields (SMFs) during magnetic resonance imaging (MRI) examinations raises concerns of adverse health effects. In this study, personal exposure monitoring of the magnetic fields during routine examinations in two 3 T MRI systems was carried out. A three-axis Hall magnetometer was attached to a subject's chest during monitoring. Data acquisition started every time the subject entered the scanner room and ended when the subject exited the room. Four radiologic technologists from two different institutes participated in this study. The maximum exposed field ranged from 0 to 1250 mT and the average peak magnetic field (B) was 428 ± 231 mT (mean ± standard deviation (SD): number of samples (N) = 103). Then, the relationship between exposure levels and work duties was analyzed. The MRI examination of the head or neck showed the highest average peak B among four work categories. These results provide information of real exposure levels for 3 T MRI system operators and can also improve the current practical training advice for preventing extra occupational field exposure.
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