Courtesy of Dr Sydney Williams, Dr Sarah Allwood-Spiers, Dr Paul McElhinney, Dr Yuehui Tao, Dr John Foster, Prof David Porter, and Dr Shajan Gunamony, this image presents a visual explanation of parallel transmit (pTx) MRI, a method for combatting non-uniformity in the radiofrequency magnetic field. Such non-uniformity is a challenge for 7T MRI because the shorter wavelength in tissue (compared to lower field strengths such as 1.5T and 3T) results in an inhomogeneous image. In pTx, individual transmission channels are controlled independently to craft a more homogeneous field.
This animated image shows data from an in-house pTx head coil built and validated for use in vivo at the Imaging Centre of Excellence (ICE) in Glasgow, demonstrating how the combined field distribution in pTx improves signal and image contrast. Dissemination of this work from the research team at ICE at the 2020 SINAPSE Annual Scientific Meeting was very well received, with a Best Poster award going to Dr Williams for her presentation on the first in vivo images acquired with the in-house pTx head coil, and a Best Proffered Talk award going to Dr Allwood-Spiers for her presentation on the safety validation process for pTx scanning.