B1-Control Loop Array for Reduction of B1 Inhomogeneity

Yukio Kaneko¹, Hideta Habara¹, Yoshihisa Soutome¹, Hisaaki Ochi¹, Yoshitaka Bito¹

We have proposed a new method of B1 homogenization: using a B1-control loop array combined with RF shimming. The loop, which has sufficiently lower resonance frequency than the transmit RF frequency, exhibits inductive characteristics. The inductive loop can change the magnetic flux because of an electrical counter current flow. The spatial distribution of the flux density around the loop has a potential to compensate the B1 inhomogeneity. Both FDTD simulation and experiments were conducted, and we found that the B1-control loop array, used with RF shimming, was more effective in reducing B1 inhomogeneity than RF shimming alone.