Flexible metamaterial lens for magnetic field and signal-to-noise ratio improvements in 1.5 T and 3 T magnetic resonance imaging

This work presents a thin printed circuit board (PCB) based flexible metamaterial (MTM) lens that can operate for both 1.5 T (63.8 MHz) and 3 T (127.7 MHz) magnetic resonance imaging (MRI) systems. The flexible MTM lens is embedded between a scanning object and receiver coil to focus the magnetic field toward the receiver coil, thereby enhancing the signal-to-noise (SNR) ratio greatly. A flexible MTM lens is designed, fabricated, and characterized. The measurement results show that the demonstrated MTM lens is highly effective for magnifying the magnetic fields generated by the Tx coil, thereby increasing the RF power captured by the Rx coil for both frequency bands which leads to the SNR improvement in 1.5 T and 3 T MRI.