Improved Fetal Magnetic Resonance Imaging Using a Flexible Metasurface.

Abstract

Recent advancements in magnetic resonance imaging (MRI) techniques are promising for the detection of fetal abnormalities, and MRI may supplement or replace prenatal ultrasound scans in the future. In particular, the interest of scientific and medical communities in high-field (3T) MRI continues to grow due to its improved contrast-to-noise and signal-to-noise ratios compared to clinical MRI of lower field strength (1.5T). However, 3T MRI shows more prominent dielectric artifacts due to constructive and destructive interference of standing waves inside the body at these frequencies. Here, we present a concept of passive radiofrequency shimming using metasurface-based pads to improve image quality in fetal MRI at 3T. The proposed metasurface increases the efficiency and homogeneity of the radiofrequency magnetic field, reducing dielectric artifacts in the fetal body and brain images. We offer an ultralight and compact passive way to improve 3T imaging of fetal brain and body structures, simplifying clinical workflows and decreasing the procedure time.