Magnetic metasurface add-ons-A route towards making MRI more efficient, affordable and accessible

Magnetic resonance imaging (MRI) is a popular non-invasive diagnostic tool used for detecting health problems in human bodies. 90% of the world population do not have access to MRI due to high cost involved in it. High field MRI (3T and above) involves bulky and expensive equipments which are unaffordable in economically backward nations. Presently, 1.5T MRI has the largest market share, at 47 percent by value and 52 percent share by volume, since it provides adequate image quality at a comparatively low cost. However, the scan-time in 1.5T is quite long. Lower scan-time in 1.5T MRI can be obtained by increasing the signal-to-noise ratio (SNR). One of the techniques of improving the SNR of MRI is deployment of metasurfaces for enhancing the RF magnetic field in the region of interest (ROI). In this work, we demonstrate the design of a single-layered thin metasurface which exhibits resonance at 63.8 MHz, the Larmor frequency of 1.5T MRI. Numerical simulations using finite integration technique show twenty-fold increase of magnetic flux density on the surface of a human phantom. The increase in the RF magnetic flux density results in improvement of signal-to-noise ratio (SNR) which can make MRI more efficient, affordable and accessible.