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Abstract #2821

A Portable MR Exposure Monitoring System for B0 and DB/dt Up to 7T.

Jens Groebner1, 2, Reiner Umathum2, Michael Bock1

1Dept. of Radiology / Medical Physics, University Medical Center Freiburg, Freiburg, BW, Germany; 2Dept. of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, BW, Germany

The EU directive 2004/40/EC is currently under review and will be replaced in future. In this study a wireless MR exposure monitoring probe is presented for exposure monitoring. A magnetic field probe consisting of three Hall sensors and induction coils is worn at the head of a volunteer. The exposure data (<I>B</I>0, d<I>B</I>/d<I>t</I>, d<I>B</I>/d<I>t</I>rot+trans*) is recorded on a SD memory card. Six measurements were performed in the vicinity of a 7T MR system. The new limits would only be exceeded during measurements in a frequency range of 0.6-1Hz and if the ICNIRP definition of d<I>B</I>/d<I>t</I>rot+trans is used.*according to ICNIRP

Keywords

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