Combined Shim-RF Array for Highly Efficient Shimming of the Brain at 7 Tesla

Jason P. Stockmann¹, Thomas Witzel¹, James N. Blau¹, Jonathan R. Polimeni¹, Wei Zhao¹, Boris Keil¹, Lawrence L. Wald¹

Multi-coil shimming shows great potential for canceling B0 inhomogeneity at ultra-high field, but its performance has been limited by the need to leave space for RF receive coils, pushing the shim coils further away from the body. We overcome this problem by combining the shim and receive RF currents through a single conductor thus optimizing the performance of both systems by bringing them as close to the body as possible. Experimental results show that shim-RF coils provide equivalent SNR to conventional receive coils and single loop shim structures can effectively shim the brain with <5A current per loop.