title: A novel coil array for combined TMS/fMRI experiments at 3 T.
abstract: OBJECTIVE
  To overcome current limitations in combined transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) studies by employing a dedicated coil array design for 3 Tesla.
  
  
  METHODS
  The state-of-the-art setup for concurrent TMS/fMRI is to use a large birdcage head coil, with the TMS between the subject's head and the MR coil. This setup has drawbacks in sensitivity, positioning, and available imaging techniques. In this study, an ultraslim 7-channel receive-only coil array for 3 T, which can be placed between the subject's head and the TMS, is presented. Interactions between the devices are investigated and the performance of the new setup is evaluated in comparison to the state-of-the-art setup.
  
  
  RESULTS
  MR sensitivity obtained at the depth of the TMS stimulation is increased by a factor of five. Parallel imaging with an acceleration factor of two is feasible with low g-factors. Possible interactions between TMS and the novel hardware were investigated and were found negligible.
  
  
  CONCLUSIONS
  The novel coil array is safe, strongly improves signal-to-noise ratio in concurrent TMS/fMRI experiments, enables parallel imaging, and allows for flexible positioning of the TMS on the head while ensuring efficient TMS stimulation due to its ultraslim design.
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Lucia I
authors.initials: LI
authors.lastname: Navarro de Lara
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Windischberger
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Andre
authors.initials: A
authors.lastname: Kuehne
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Woletz
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Sieg
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, London, United Kingdom.
authors.forename: Sven
authors.initials: S
authors.lastname: Bestmann
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Weiskopf
authors.affiliation: MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.|Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Strasser
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Ewald
authors.initials: E
authors.lastname: Moser
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.|MR Centre of Excellence, Medical University of Vienna, Vienna, Austria.
authors.forename: Elmar
authors.initials: E
authors.lastname: Laistler
mesh_terms: D000328:Adult; D003198:Computer Simulation; D004867:Equipment Design; D005260:Female; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D050781:Transcranial Magnetic Stimulation / Q000295:instrumentation* / Q000379:methods*
keywords: TMS; coil array; concurrent TMS/fMRI; fMRI; parallel imaging