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Physiological Side Effects of Fast Gradient Switching

  • F. Schmitt
  • W. Irnich
  • H. Fischer

Abstract

Three types of electromagnetic fields are involved in magnetic resonance imaging (MRI): the static magnetic field, Bo, the radiofrequency (RF) magnetic field, B1, and the time-varying gradient magnetic field, BG. Physiological effects resulting from the interaction of these fields with biological tissue are reported in the literature [1]. Effects from strong Bo fields are wide-ranging and often contradictory [2]. At the moment there is no evidence for hazardous or irreversible effects related to exposure to static magnetic fields up to a field strength of 2 T. Studies with whole-body 4-T scanners, however, report unwanted side effects [3] which are not of great concern for further research. All RF power used in MRI is converted into heat within the human tissue [4] due to the conductivity of the tissue.

Keywords

Magnetic Flux Stimulus Duration Acoustic Noise Pause Time Gradient Coil 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • F. Schmitt
  • W. Irnich
  • H. Fischer

There are no affiliations available

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