SEMINAR

DEPARTMENT OF BIOMEDICAL ENGINEERING

The Dynamic Multi-Coil Technique (DYNAMITE) - A novel MR Imaging and B­₀ Shimming Concept

Prof. Christoph Juchem, Departments of Biomedical Engineering and Radiology Columbia University

Abstract

In my talk, I will present a technique for B0 magnetic field modeling that is based on the combination of fields generated by a matrix of small, individually driven generic coils. This multi-coil approach enables the accurate generation of simple and complex magnetic field shapes in a flexible fashion. B0 shimming with the dynamic multi-coil technique (DYNAMITE) outperforms conventional methods based on spherical harmonic functions and provides unrivaled magnetic field homogeneity in mouse, rat and human brain. Along with the efficiency gains of DYNAMITE shimming compared to spherical harmonic approaches, the multi-coil concept has the potential to replace conventional shim systems that are based on sets of dedicated SH coils and allow optimal object-specific shim solutions similar to object-specific RF coils. The technology furthermore lends itself to spatial encoding. I will present MRI results, including concomitant imaging and B0 shimming, in which all fields are purely DYNAMITE-based and conclude with the first realization of DYNAMITE MRI of the in vivo human brain. The obtained image fidelity is comparable to MRI with conventional gradient coils, paving the way for full-fledged human DYNAMITE MRI systems.