A Preliminary Study of a Conformal Electromagnetic Metasurface for Brain Tumor Detection

We introduce a radiofrequency system for brain tumor detection, where a conformal metasurface is employed, by opportunely modifying the classical planar structure. The proposed system, working at 3 MHz, consists in a 5×5 matrix whose unit-cells are made of 8-turn spirals, excited by an active RF coil placed in its near-field region. The detection of the tumors is carried out by observing the amplitude variation and the frequency shift of the driving coil input impedance. By performing accurate full-wave simulations, we demonstrated that, by designing the metasurface in order to produce a 5-spot magnetic field distribution, it is possible to detect and spatially identify brain tumor malignancies, despite the extremely low frequency herein adopted. The findings, obtained from accurate numerical simulations, suggest that the conformal near-field focused metasurface is able to detect inclusions as small as 1 mm, demonstrating excellent sensitivity and spatial resolution. Future studies and developments will be aimed at exploiting a real-time reconfigurability to sequentially scan the tissue or region of interest.