Double-Sided Individually Shielded Monopole Antenna Array Design for Ultra High Field (UHF) MRI

In this paper, we evaluate a double-sided monopole antenna array with 8 monopole elements at 298MHz. Radio Frequency (RF) coil development and design become challenging in ultra-high field magnetic resonance imaging (MRI) operating at frequencies of 298 MHz and above because of some factors such as inhomogeneity in the RF field, relatively short wavelength, RF coil sensitivity, specific absorption rate (SAR), connection and interference between coil components. To get over these drawbacks, we propose to use an individually shielded double-sided monopole antenna for ultra-high field (UHF) MRI head imaging. Compared to a shielded monopole antenna, our suggested double sided antenna showed an improvement in magnetic flux density and field homogeneity based on simulation and experiment. Observing the highest field intensity values, we find the double-sided value is
$4.74\mathbf{X}{10^{ - 5}}\mathbf{T}$
whereas the highest value for the previously shielded monopole antenna is
$4.04\mathbf{X}{10^{ - 8}}\mathbf{T}$
. Using COMSOL MULTIPHYSICS simulation we examined how increasing the number of shielded monopole antenna with double-sided can maximize array sensitivity with RF field homogeneity. Based on our findings, a properly oriented double-sided shielded monopole antenna array may be able to provide field uniformity and RF coil sensitivity above the benchmark for ultra-high field magnetic resonance imaging applications.