Patent ID: 8760160

Claim:
An MRI apparatus comprising: a magnetic resonance imaging (MRI) system having: a magnet coil assembly having a magnet coil bore extending therethrough; a gradient coil assembly positioned within the magnet coil bore and having a gradient coil bore extending therethrough; a waveguide positioned within the gradient coil bore, the waveguide having a waveguide bore extending therethrough; a transmission line coupled to the waveguide, the waveguide forming a single conductor waveguide; and a computer programmed to: access a scan sequence comprising an RF pulse sequence; execute the scan sequence; during execution of the scan sequence: operate the waveguide in a hybrid mode to transmit an RF pulse of the RF pulse scan sequence as a travelling wave at a frequency lower than a cutoff frequency of a principal mode of the waveguide absent a dielectric core; and acquire MR signals from an imaging subject positioned within the waveguide bore; and reconstruct an image based on the acquired MR signals.