Mid-Bore Excitation of Traveling Waves with an Annular Ladder Resonator for 7T Body Imaging with Reduced SAR

Graham Charles Wiggins¹, Bei Zhang¹, Riccardo Lattanzi¹, Daniel Sodickson¹

Traveling wave imaging has previously been demonstrated using a patch antenna placed at one end of the scanner bore. For body imaging, reflections and attenuation result in very low B1+ in the torso. Attempting torso imaging by boosting the transmit power can create too much heating of tissue between the antenna and the region of interest, particularly in the head. We propose a novel coil design which can be placed at or near isocenter to create a traveling wave excitation which is strongest in the torso, with significantly reduced SAR in distant tissues.