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A novel tool for estimation of magnetic resonance occupational exposure to spatially varying magnetic fields

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Magnetic Resonance Materials in Physics, Biology and Medicine Aims and scope Submit manuscript

Abstract

Object

Staff operating in the environment of magnetic resonance imaging (MRI) scanners are exposed daily to static magnetic fields (MFs). To protect workers several guidelines are present in literature reporting exposure limits values expressed in terms of magnetic flux density or induced current density. We present here a novel tool for estimating the induced current density due to worker movement in the MR environment.

Materials and methods

A Matlab script was created to estimate the induced current density J due to operator movements along a chosen walking path.

Results

The induced current density associated with any worker’s movements during MR procedures is dependent on the walking speed and on the spatial gradient fields associated with a specific path. Some examples of possible worker paths were considered here for a 3 T MR scanner and a maximum value of 160 cm/s walking speed.

Conclusion

This tool permits one to find exposure level for specific worker walking path and speed; it can be used as assessment tool in any MRI centre and for workers safety education. It is valid for any kind of commercial scanner because it requires only the knowledge of the MR scanner room map with isogauss lines.

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Authors and Affiliations

  1. Institute of Clinical Physiology, National Council of Research, via G. Moruzzi 1, 56124, Pisa, Italy

    Valentina Hartwig, Nicola Vanello, Giulio Giovannetti & Maria Filomena Santarelli

  2. Department of Information Engineering, University of Pisa, via G. Caruso 16, 56126, Pisa, Italy

    Nicola Vanello & Luigi Landini

  3. Fondazione G. Monasterio CNR-Regione Toscana, Pisa, Italy

    Massimo Lombardi & Luigi Landini

Authors
  1. Valentina Hartwig
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  2. Nicola Vanello
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  3. Giulio Giovannetti
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  4. Massimo Lombardi
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  5. Luigi Landini
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  6. Maria Filomena Santarelli
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Corresponding author

Correspondence to Valentina Hartwig.

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Hartwig, V., Vanello, N., Giovannetti, G. et al. A novel tool for estimation of magnetic resonance occupational exposure to spatially varying magnetic fields. Magn Reson Mater Phy 24, 323–330 (2011). https://doi.org/10.1007/s10334-011-0279-2

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  • DOI: https://doi.org/10.1007/s10334-011-0279-2

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