Design and additive manufacturing of MRI gradient coils

Abstract

The current manufacturing process of MRI gradient coils is a lengthy process because of material property requirements that address high voltages and currents, and complex 3D geometries (necessary to achieve desired gradient profiles and high magnetic field strengths). To address these requirements we developed software and fast 3D printer technology that automates the design, optimization, and manufacturing of these gradient coils. Our design software applies the principles of 3D printing (rapid prototyping) to control the gradient coil manufacturing process. Our 3D printer is the first printer to combine electrical conductors (e.g. silver) and high-grade electrical insulators (e.g., Kapton) for manufacturing MRI gradient coils. We have applied the additive manufacturing (3D printing) methods to the design and manufacturing of ultra-strong and ultra-fast (rise time ≤ 10 µs) magnetic gradient coils for high-performance magnetic resonance imaging (MRI) systems. Experiments with bi-planar 3D-printed gradient coils installed in a tabletop MRI system (0.34 T) show that we can get images with in-plane resolution of 50 µm and good image signal-to-noise in seconds using fast pulse sequences (fast gradient echo).