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Heating and Safety Concerns of the Radio-Frequency Field in MRI

Abstract

Magnetic resonance imaging (MRI) is a widely used and powerful imaging technique for non-invasive clinical diagnosis. The absorbed radiofrequency (RF) energy must be carefully managed, as MRI presents one of the highest RF exposures to humans. Temperature increases in the patient caused by high-level RF exposure is a major safety concern in MRI, potentially causing local thermal tissue damage or systemic overheating. This review article summarizes recent findings in MR safety research, including the clear distinction between exposures of patients with and without implants; evaluates the advantages and limitations of numerical simulations for RF safety assessment in MRI; and discusses the need for additional research at high RF exposure levels and in novel MRI systems.

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Correspondence to Niels Kuster.

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Conflict of Interest

Prof. Niels Kuster reports grants from CTI - Commission for Technology and Innovation, Switzerland, grants from Schmid & Partner Engineering AG, Switzerland, grants from ZMT Zurich MedTech AG, Switzerland, grants from Siemens Health Care GmbH, Germany, grants from GE Medical Systems, USA, during the conduct of the study; other from Boston Scientific Corp., USA, other from Micro Systems Engineering Inc., USA, other from Med-El, Austria, other from Sorin CRM S.A.S., France, other from Nevro Corp., USA, other from St. Jude Medical Inc., USA.

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Murbach, M., Zastrow, E., Neufeld, E. et al. Heating and Safety Concerns of the Radio-Frequency Field in MRI. Curr Radiol Rep 3, 45 (2015). https://doi.org/10.1007/s40134-015-0128-6

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Keywords

  • MRI safety
  • RF exposure
  • SAR
  • In silico assessment
  • Exposure assessment
  • Thermal dose