A Simple Relationship for High Efficiency–Gradient Uniformity Tradeoff in Multilayer Asymmetric Gradient Coils for Magnetic Resonance Imaging

High-quality gradient coils are pivotal to advances in magnetic resonance imaging (MRI). We have studied the influence of coil dimensions and target requirements in multilayer, asymmetric, transverse gradient coils. We developed a simple linear function that defines the optimal coil length to produce a maximum figure of merit given an imaging region size and location, coil radius, and gradient nonuniformity. Our method, based on the linear function, yields high-quality solutions. The method introduces two torque/force minimization strategies in order to obtain asymmetric transverse gradient coils that balance minimum torque with a maximum figure of merit. High-performance head, asymmetric gradient coils with simple current patterns and minimum torque can be tailored to a specific magnet design, as we illustrate