Dual-purpose arrays of close-fitting coils, used to both receive RF and shim B0 to high spatial order, have recently been demonstrated in brain imaging at 3T. We extend this approach to 7T with an array comprised of: six RF coils, twenty-six RF/B0-shim coils, and six shim-only coils. The shim coils are driven by an array of low-cost current-feedback amplifiers that can steer up to fifty amps of shimming currents rapidly and accurately enough to allow for slice-by-slice adjustments. The resulting slice-optimal high-order shim capability (wires and chokes) improves σB0 in brain slices by up to 60% (as compared to static 2nd-order global shimming), while worsening SNR by less than 10%, and increasing coil coupling by less than 3%.
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