Remote RF excitation for a small-bore MR imager at 15.2 T

TL;DR

This paper demonstrates that travelling-wave MRI using a simple waveguide can produce high-quality mouse images at 15.2T, addressing B1 inhomogeneity issues at ultra-high field strengths.

Contribution

The study introduces a practical implementation of travelling-wave MRI with a parallel-plate waveguide for small-bore imaging at 15.2T, avoiding complex dielectric materials.

Findings

High SNR mouse images at 15.2T using travelling-wave MRI

Results are consistent with lower field strengths (3T and 9.4T)

Simple waveguide effectively overcomes B1 inhomogeneity

Abstract

The travelling-wave MRI approach is an alternative to overcome the B1 inhomogeneity at UHF MRI for human applications. More recently, this concept has been also used with animal MR imagers. We used a parallel-plate waveguide and a bio-inspired surface coil to generate mouse images at 15.2T. Ex vivo mouse images were acquired without high dielectric materials to conduct the signal at the right frequency. These results are in very good concordance with results obtained at 3T and 9.4T. These results show that travelling wave MRI with high SNR can be performed with a simple waveguide.