title: Modular 32-channel transceiver coil array for cardiac MRI at 7.0T.
abstract: OBJECTIVE
  To design and evaluate a modular transceiver coil array with 32 independent channels for cardiac MRI at 7.0T.
  
  
  METHODS
  The modular coil array comprises eight independent building blocks, each containing four transceiver loop elements. Numerical simulations were used for B1 (+) field homogenization and radiofrequency (RF) safety validation. RF characteristics were examined in a phantom study. The array's suitability for accelerated high spatial resolution two-dimensional (2D) FLASH CINE imaging of the heart was examined in a volunteer study.
  
  
  RESULTS
  Transmission field adjustments and RF characteristics were found to be suitable for the volunteer study. The signal-to-noise intrinsic to 7.0T together with the coil performance afforded a spatial resolution of 1.1 × 1.1 × 2.5 mm(3) for 2D CINE FLASH MRI, which is by a factor of 6 superior to standardized CINE protocols used in clinical practice at 1.5T. The 32-channel transceiver array supports one-dimensional acceleration factors of up to R = 4 without impairing image quality significantly.
  
  
  CONCLUSIONS
  The modular 32-channel transceiver cardiac array supports accelerated and high spatial resolution cardiac MRI. The array is compatible with multichannel transmission and provides a technological basis for future clinical assessment of parallel transmission techniques at 7.0T.
authors.affiliation: Berlin Ultrahigh Field Facility, Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Graessl
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Renz
authors.forename: Fabian
authors.initials: F
authors.lastname: Hezel
authors.forename: Matthias A
authors.initials: MA
authors.lastname: Dieringer
authors.forename: Lukas
authors.initials: L
authors.lastname: Winter
authors.forename: Celal
authors.initials: C
authors.lastname: Oezerdem
authors.forename: Jan
authors.initials: J
authors.lastname: Rieger
authors.forename: Peter
authors.initials: P
authors.lastname: Kellman
authors.forename: Davide
authors.initials: D
authors.lastname: Santoro
authors.forename: Tomasz D
authors.initials: TD
authors.lastname: Lindel
authors.forename: Tobias
authors.initials: T
authors.lastname: Frauenrath
authors.forename: Harald
authors.initials: H
authors.lastname: Pfeiffer
authors.forename: Thoralf
authors.initials: T
authors.lastname: Niendorf
mesh_terms: D000328:Adult; D003198:Computer Simulation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D064368:Healthy Volunteers; D006321:Heart; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation; D019028:Magnetic Resonance Imaging, Cine / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D011846:Radio Waves; D014159:Transducers
keywords: cardiovascular MRI; parallel imaging; transceiver array; ultrahigh-field MRI