A dual-frequency MRI coil for small animal imaging at 7 Tesla based on metamaterial-inspired wire structures

In this contribution we propose and test a new design of radio frequency coils for imaging of small animals in 7T MRI. The proposed coils take advantage of periodic structures composed of thin printed metal strips, which can be efficiently excited by a small loop feed at multiple frequencies. This effect is attributed to a strong coupling between the loop and hybridized eigenmodes of the wire structure. By numerical simulations it was shown that the proposed approach provides dual-frequency impedance matching at 282.6 and 300.1 MHz, which is required for molecular
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F and
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H imaging at 7 Tesla to reach a sufficient signal-to-noise ratio.