Reducing SAR and enhancing cerebral signal-to-noise ratio with high permittivity padding at 3 T.

Previous works have shown that placement of a high-dielectric pad can improve image intensity in a region adjacent to the pad, or that placement of dielectric pads around a large surface of the head can improve image homogeneity on an entire plane through the head in high-field MRI. Here, experimental results show that use of high-dielectric pads around the human head can reduce the required input radiofrequency power by 50% while enhancing image signal-to-noise ratio by 20-40% throughout the cerebrum at 3 T. Thus, dielectric pads may be used to provide a relatively simple and low-cost method for improving quality and safety of MRI in a variety of applications at 3 T.