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Objective: Global Maxwell Tomography (GMT) is a recently introducedvolumetric technique for noninvasive estimation of electrical properties (EP)from magnetic resonance measurements. Previous work evaluated GMT using idealradiofrequency (RF) excitations. The aim of this simulation study was to assessGMT performance with a realistic RF coil. Methods: We designed atransmit-receive RF coil with $8$ decoupled channels for $7$T head imaging. Wecalculated the RF transmit field ($B_1^+$) inside heterogeneous head models fordifferent RF shimming approaches, and used them as input for GMT to reconstructEP for all voxels. Results: Coil tuning/decoupling remained relatively stablewhen the coil was loaded with different head models. Mean error in EPestimation changed from $7.5\%$ to $9.5\%$ and from $4.8\%$ to $7.2\%$ forrelative permittivity and conductivity, respectively, when changing head modelwithout re-tuning the coil. Results slightly improved when an SVD-based RFshimming algorithm was applied, in place of excitation with one coil at a time.Despite errors in EP, RF transmit field ($B_1^+$) and absorbed power could bepredicted with less than $0.5\%$ error over the entire head. GMT couldaccurately detect a numerically inserted tumor. Conclusion: This workdemonstrates that GMT can reliably reconstruct EP in realistic simulatedscenarios using a tailored 8-channel RF coil design at $7$T. Future work willfocus on construction of the coil and optimization of GMT's robustness tonoise, to enable in-vivo GMT experiments. Significance: GMT could provideaccurate estimations of tissue EP, which could be used as biomarkers and couldenable patient-specific estimation of RF power deposition, which is an unsolvedproblem for ultra-high-field magnetic resonance imaging.

Magnetic-resonance-based electrical property mapping using Global Maxwell Tomography with an 8-channel head coil at 7 Tesla: a simulation study