@article{OrzadaJohstMaderwaldetal.2013,
  author    = {Orzada, Stephan and Johst, S{\"o}ren and Maderwald, Stefan and Bitz, Andreas and Solbach, Klaus and Ladd, Mark E.},
  title     = {Mitigation of B1(+) inhomogeneity on single-channel transmit systems with TIAMO},
  series = {Magnetic Resonance in Medicine},
  volume    = {70},
  journal   = {Magnetic Resonance in Medicine},
  number    = {1},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.24453},
  pages     = {290 -- 294},
  year      = {2013},
  language  = {en}
}
@article{OrzadaBitzSchaeferetal.2011,
  author    = {Orzada, Stephan and Bitz, Andreas and Sch{\"a}fer, Lena C. and Ladd, Susanne C. and Ladd, Mark E. and Maderwald, Stefan},
  title     = {Open design eight-channel transmit/receive coil for high-resolution and real-time ankle imaging at 7 T},
  series = {Medical Physics},
  volume    = {38},
  journal   = {Medical Physics},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {2473-4209},
  doi       = {10.1118/1.3553399},
  pages     = {1162 -- 1167},
  year      = {2011},
  abstract  = {Purpose: At 1.5 T, real-time MRI of joint movement has been shown to be feasible. However, 7 T, provides higher SNR and thus an improved potential for parallel imaging acceleration. The purpose of this work was to build an open, U-shaped eight-channel transmit/receive microstrip coil for 7 T MRI to enable high-resolution and real-time imaging of the moving ankle joint. Methods: A U-shaped eight-channel transmit/receive array for the human ankle was built.urn:x-wiley:00942405:mp3399:equation:mp3399-math-0001-parameters and urn:x-wiley:00942405:mp3399:equation:mp3399-math-0002-factor were measured. SAR calculations of different ankle postures were performed to ensure patient safety. Inhomogeneities in the transmit field consequent to the open design were compensated for by the use of static RF shimming. High-resolution and real-time imaging was performed in human volunteers. Results: The presented array showed good performance with regard to patient comfort and image quality. High acceleration factors of up to 4 are feasible without visible acceleration artifacts. Reasonable image homogeneity was achieved with RF shimming. Conclusions: Open, noncylindrical designs for transmit/receive coils are practical at 7 T and real-time imaging of the moving joint is feasible with the presented coil design.},
  language  = {en}
}
@article{KraffBitzBreyeretal.2011,
  author    = {Kraff, Oliver and Bitz, Andreas and Breyer, Tobias and Kruszona, Stefan and Maderwald, Stefan and Brote, Irina and Gizewski, Elke R. and Ladd, Mark E. and Quick, Harald H.},
  title     = {A transmit/receive radiofrequency array for imaging the carotid arteries at 7 Tesla: coil design and first in vivo results},
  series = {Investigative Radiology},
  volume    = {46},
  journal   = {Investigative Radiology},
  number    = {4},
  publisher = {Wolters Kluwer},
  address   = {K{\"o}ln},
  issn      = {1536-0210},
  doi       = {10.1097/RLI.0b013e318206cee4},
  pages     = {246 -- 254},
  year      = {2011},
  abstract  = {Objective: To develop a transmit/receive radiofrequency (RF) array for magnetic resonance imaging (MRI) of the carotid arteries at 7 T. The prototype is characterized in numerical simulations and bench measurements, and the feasibility of plaque imaging at 7 T is demonstrated in first in vivo images. Materials and Methods: The RF phased array coil consists of 8 surface loop coils. To allow imaging of both sides of the neck, the RF array is divided into 2 coil clusters, each with 4 overlapping loop elements. For safety validation, numerical computations of the RF field distribution and the corresponding specific absorption rate were performed on the basis of a heterogeneous human body model. To validate the coil model, maps of the transmit B1+ field were compared between simulation and measurement. In vivo images of a healthy volunteer and a patient (ulcerating plaque and a 50\% stenosis of the right internal carotid artery) were acquired using a 3-dimensional FLASH sequence with a high isotropic spatial resolution of 0.54 mm as well as using pulse-triggered proton density (PD)/T2-weighted turbo spin echo sequences. Results: Measurements of the S-parameters yielded a reflection and isolation of the coil elements of better than -18 and -13 dB, respectively. Measurements of the g-factor indicated good image quality for parallel imaging acceleration factors up to 2.4. A similar distribution and a very good match of the absolute values were found between the measured and simulated B1+ transmit RF field for the validation of the coil model. In vivo images revealed good signal excitation of both sides of the neck and a high vessel-to-background image contrast for the noncontrast-enhanced 3-dimensional FLASH sequence. Imaging at 7 T could depict the extent of stenosis, and revealed the disruption and ulcer of the plaque. Conclusions: This study demonstrates that 2 four-channel transmit/receive RF arrays for each side of the neck is a suitable concept for in vivo MRI of the carotid arteries at 7 Tesla. Further studies are needed to explore and exploit the full potential of 7 T high-field MRI for carotid atherosclerotic plaque imaging.},
  language  = {en}
}
@inproceedings{BitzKobusScheenenetal.2013,
  author    = {Bitz, Andreas and Kobus, Thiele and Scheenen, Tom W. J. and Ladd, Mark E.},
  title     = {RF Safety of the Combination of a 31P Tx/Rx Endorectal Coil \& a 1H Tx/Rx Body Array for 31P MRSI of the Prostate at 7T (311.)},
  series = {20th Annual ISMRM scientific meeting and exhibition 2012 : Melbourne, Australia, 5 - 11 May 2012},
  booktitle = {20th Annual ISMRM scientific meeting and exhibition 2012 : Melbourne, Australia, 5 - 11 May 2012},
  number    = {Volume 1},
  publisher = {Curran},
  address   = {Red Hook, NY},
  isbn      = {978-1-62276-943-8},
  issn      = {1545-4428},
  pages     = {311},
  year      = {2013},
  language  = {en}
}
@article{KraffBitzKruszonaetal.2009,
  author    = {Kraff, Oliver and Bitz, Andreas and Kruszona, Stefan and Orzada, Stephan and Schaefer, Lena C. and Theysohn, Jens M. and Maderwald, Stefan and Ladd, Mark E. and Quick, Harald H.},
  title     = {An eight-channel phased array RF coil for spine MR imaging at 7 T},
  series = {Investigative Radiology},
  volume    = {44},
  journal   = {Investigative Radiology},
  number    = {11},
  publisher = {Lippincott Williams \& Wilkins},
  issn      = {1536-0210},
  doi       = {10.1097/RLI.0b013e3181b24ab7},
  pages     = {734 -- 740},
  year      = {2009},
  language  = {en}
}
@article{RietschPfaffenrotBitzetal.2017,
  author    = {Rietsch, Stefan H. G. and Pfaffenrot, Viktor and Bitz, Andreas and Orzada, Stephan and Brunheim, Sascha and Lazik-Palm, Andrea and Theysohn, Jens M. and Ladd, Mark E. and Quick, Harald H. and Kraff, Oliver},
  title     = {An 8-channel transceiver 7-channel receive RF coil setup for high SNR ultrahigh-field MRI of the shoulder at 7T},
  series = {Medical Physics},
  journal   = {Medical Physics},
  number    = {Article in press},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0094-2405},
  doi       = {10.1002/mp.12612},
  year      = {2017},
  language  = {en}
}
@article{OrzadaBitzJohstetal.2017,
  author    = {Orzada, Stephan and Bitz, Andreas and Johst, S{\"o}ren and Gratz, Marcel and V{\"o}lker, Maximilian N. and Kraff, Oliver and Abuelhaija, Ashraf and Fiedler, Thomas M. and Solbach, Klaus and Quick, Harald H. and Ladd, Mark E.},
  title     = {Analysis of an integrated 8-Channel Tx/Rx body array for use as a body coil in 7-Tesla MRI},
  series = {Frontiers in Physics},
  volume    = {5},
  journal   = {Frontiers in Physics},
  number    = {Jun},
  issn      = {2296-424X},
  doi       = {10.3389/fphy.2017.00017},
  year      = {2017},
  language  = {en}
}
@article{RietschBrunheimOrzadaetal.2019,
  author    = {Rietsch, Stefan H. G. and Brunheim, Sascha and Orzada, Stephan and Voelker, Maximilian N. and Maderwald, Stefan and Bitz, Andreas and Gratz, Marcel and Ladd, Mark E. and Quick, Harald H.},
  title     = {Development and evaluation of a 16-channel receive-only RF coil to improve 7T ultra-high field body MRI with focus on the spine},
  series = {Magnetic Resonance in Medicine},
  journal   = {Magnetic Resonance in Medicine},
  number    = {Early view},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.27731},
  year      = {2019},
  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{NoureddineKraffLaddetal.2019,
  author    = {Noureddine, Yacine and Kraff, Oliver and Ladd, Mark E. and Wrede, Karsten and Chen, Bixia and Quick, Harald H. and Schaefers, Georg and Bitz, Andreas},
  title     = {Radiofrequency induced heating around aneurysm clips using a generic birdcage head coil at 7 Tesla under consideration of the minimum distance to decouple multiple aneurysm clips},
  series = {Magnetic Resonance in Medicine},
  journal   = {Magnetic Resonance in Medicine},
  number    = {Early view},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.27835},
  pages     = {1 -- 17},
  year      = {2019},
  language  = {en}
}