Radiative RF antenna arrays for cardiac, brain and thermal magnetic resonance at ultrahigh and extreme magnetic field strengths: Concepts, electromagnetic field simulations and applications

A growing number of reports speak about explorations into magnetic resonance (MR) at ultrahigh magnetic fields (UHF-MR, B0≥7.0T). Realizing the research promises and clinical applications of UHF-MR this work outlines current trends in enabling radiofrequency (RF) technology tailored for MR in the low wavelength regime. For this purpose RF technology concepts based upon radiative antennae are discussed. Early applications in cardiac, brain and thermal MR at ultrahigh and extreme magnetic field strengths (B0≥11.7 T) are surveyed. The goal here is not to be comprehensive but to inspire the biomedical engineering, imaging sciences and diagnostic imaging communities to throw further weight behind the solution of the many remaining obstacles of UHF-MR with the goal to transfer MR engineering and MR physics driven methodological advancements into extra clinical value and novel applications.

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