This article present a new approach replacing high-permittivity water-based dielectric pads with a non-resonant low-cost artificial dielectric to improve MR image quality by modifying the interferences present in the radiofrequency field at 7T MRI. The artificial dielectric comprises a stack of metal patches printed on dielectric substrates. Here we focus on the method of analytical and numerical optimization of the artificial dielectric and show that the proposed structure allows obtaining the same increase in the minimum of the transmit

B1+
radio-frequency field distribution in a head phantom at 7T as the conventional dielectric pad.

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