@article{OrzadaLaddBitz2016,
  author    = {Orzada, Stephan and Ladd, Mark E. and Bitz, Andreas},
  title     = {A method to approximate maximum local SAR in multichannel transmit MR systems without transmit phase information},
  series = {Magnetic Resonance in Medicine},
  volume    = {78},
  journal   = {Magnetic Resonance in Medicine},
  number    = {2},
  publisher = {International Society for Magnetic Resonance in Medicine},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.26398},
  pages     = {805 -- 811},
  year      = {2016},
  abstract  = {Purpose To calculate local specific absorption rate (SAR) correctly, both the amplitude and phase of the signal in each transmit channel have to be known. In this work, we propose a method to derive a conservative upper bound for the local SAR, with a reasonable safety margin without knowledge of the transmit phases of the channels. Methods The proposed method uses virtual observation points (VOPs). Correction factors are calculated for each set of VOPs that prevent underestimation of local SAR when the VOPs are applied with the correct amplitudes but fixed phases. Results The proposed method proved to be superior to the worst-case calculation based on the maximum eigenvalue of the VOPs. The mean overestimation for six coil setups could be reduced, whereas no underestimation of the maximum local SAR occurred. In the best investigated case, the overestimation could be reduced from a factor of 3.3 to a factor of 1.7. Conclusion The upper bound for the local SAR calculated with the proposed method allows a fast estimation of the local SAR based on power measurements in the transmit channels and facilitates SAR monitoring in systems that do not have the capability to monitor transmit phases},
  language  = {en}
}
@article{OrzadaSolbachGratzetal.2019,
  author    = {Orzada, Stephan and Solbach, Klaus and Gratz, Marcel and Brunheim, Sascha and Fiedler, Thomas M. and Johst, S{\"o}ren and Bitz, Andreas and Shooshtary, Samaneh and Abuelhaija, Asjraf and Voelker, Maximilian N. and Rietsch, Stefan H. G. and Kraff, Oliver and Maderwald, Stefan and Fl{\"o}ser, Martina and Oehmingen, Mark and Quick, Harald H. and Ladd, Mark E.},
  title     = {A 32-channel parallel transmit system add-on for 7T MRI},
  series = {Plos one},
  journal   = {Plos one},
  doi       = {10.1371/journal.pone.0222452},
  year      = {2019},
  language  = {en}
}
@article{FaganBitzBjoerkmanBurtscheretal.2021,
  author    = {Fagan, Andrew J. and Bitz, Andreas and Bj{\"o}rkman-Burtscher, Isabella M. and Collins, Christopher M. and Kimbrell, Vera and Raaijmakers, Alexander J. E.},
  title     = {7T MR Safety},
  series = {Journal of Magnetic Resonance Imaging (JMRI)},
  volume    = {53},
  journal   = {Journal of Magnetic Resonance Imaging (JMRI)},
  number    = {2},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2586},
  doi       = {10.1002/jmri.27319},
  pages     = {333 -- 346},
  year      = {2021},
  language  = {en}
}
@article{SukhotinaStreckertBitzetal.2006,
  author    = {Sukhotina, Irina and Streckert, Joachim R. and Bitz, Andreas and Hansen, Volkert W. and Lerchl, Alexander},
  title     = {1800 MHz electromagnetic field effects on melatonin release from isolated pineal glands},
  series = {Journal of Pineal Research},
  volume    = {40},
  journal   = {Journal of Pineal Research},
  number    = {1},
  issn      = {1600-079X},
  doi       = {10.1111/j.1600-079X.2005.00284.x},
  pages     = {86 -- 91},
  year      = {2006},
  language  = {en}
}
@article{LagemaatMaasVosetal.2015,
  author    = {Lagemaat, Miriam W. and Maas, Marnix C. and Vos, Eline K. and Bitz, Andreas and Orzada, Stephan and Weiland, Elisabeth and Uden, Mark J. van and Kobus, Thiele and Heerschap, Arend and Scheenen, Tom W. J.},
  title     = {(31) P MR spectroscopic imaging of the human prostate at 7 T: T1 relaxation times, Nuclear Overhauser Effect, and spectral characterization},
  series = {Magnetic Resonance in Medicine},
  volume    = {73},
  journal   = {Magnetic Resonance in Medicine},
  number    = {3},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.25209},
  pages     = {909 -- 920},
  year      = {2015},
  language  = {en}
}