Abstract #0779

Leggett J, Green D, Bowtell R

Insert gradient coils offer significant advantages for brain imaging. Head-sized hemispherical gradient coils offer further improvements in performance compared with cylindrical coils. This enhanced performance is compromised when torque-balancing is incorporated into the design of transverse hemispherical coils. We show how the addition of a short, cylindrical coil section to the open end of the hemisphere, overcomes this problem, allowing the design of torque-balanced gradient coils which have significantly higher efficiency at fixed inductance than conventional cylindrical insert coils. A full three-axis, dome gradient coil set has been designed, built and subsequently used in brain imaging experiments at 3 T.