Interview

Abstract

Valentina Hartwig Doctor Valentina Hartwig from the National Research Council in Italy, talks to Electronics Letters about the paper ‘New device for the assessment of occupational exposure to time-varying magnetic field due to movement in Magnetic Resonance environments’, page 579. I have been intrigued by the interactions between electromagnetic fields and biological tissues for many years, and my PhD was on this topic. This is an interesting research topic and what I love most about this subject is its multidisciplinary approach. Specifically, exposure to electromagnetic fields in Magnetic Resonance (MR) environments is currently a hot topic. MR is widely used for clinical applications and, at the Institute of Clinical Physiology where I work, is also used as a powerful research tool for cardiovascular diseases. In the past, we studied patient exposure to electromagnetic fields in MR and, at present, we focus on occupational exposure in MR environments, an exciting challenge. According to the most recent international regulations and guidelines, training of MR professionals is necessary to avoid the risks of high electromagnetic field exposure. There is still the lack of a practical method for exposure assessment, particularly when considering risks for MR staff moving across the permanent static magnetic field straying from the scanner. For these reasons, we had the idea to design a device for assessing personal exposure to the magnetic fields, to use not only as a “personal dosimeter”, but also for educational purposes. Our target was using this simple instrument to identify preventive measures and to provide staff with some recommendations on how to move around the MR room during daily clinical practice. There are at present some commercial MR dosimeters, but these devices have been designed for exposure assessment purposes at only one position on the workers body and are not suitable for newer research MR scanners with very high values of static magnetic fields. Our device is designed for research purposes, offering the possibility to measure the magnetic field at different positions on the body simultaneously, which is important in epidemiological studies. Moreover, it may be used in all clinical MR environments and in experimental MR scanners with a static magnetic field value up to 7 T. In its development is encompassed our mission of “technology transfer”, from basic research to industry and, it is the result of successful cooperation between research institutions and industrial partners. An MR site is an environment which poses exciting challenges, especially for designing an electronic device for use within it, as even the simplest electronic circuit may not function correctly. Our challenge was to design a wearable device that is not affected by the fields present and permits measurement and recording of exposure parameters; all without disturbing the work of the operator wearing it. This was possible thanks to the thorough study of the chosen material and components electromagnetic compatibilities. We performed many tests both in the laboratory and in real MR environments and achieved our goal thanks to the hard work of a multidisciplinary team. In the short term, we expect that the device described in our paper will be useful in better understanding occupational exposure to magnetic fields in MR sites. In the longer term, after optimisation of the present prototype, the device may be commercialised and used for workers training and/or epidemiological studies. Future developments of this work will regard the optimisation of the device in terms of size, storage capacity, and the implementation of a wireless-real-time connection to a host device. We are also working on a computational tool for the estimation of occupational exposure to time-varying electromagnetic fields due to the movement inside the MR environment. In recent years, the scientific community's interest in MR environment safety has been growing exponentially, especially after the publication, in 2013, of a specific Directive of the EU, followed in 2014 by updated ICNIRP guidelines. To date, there are many scientific works which deal with MR safety, hence we have a good understanding of magnetic field exposure levels by workers. What is still missing today are epidemiological studies conducted using consolidated assessment methodologies to collect exposure data at a personal level by means of simple everyday equipment. I think that over the next ten years research on this topic will grow both from the point of view of studies on the biological effects of electromagnetic fields typical of the MR environment, and from that of devices for measuring exposure to this type of physical agents. Our work will, therefore, contribute to this latter research activity.