Novel gradient coil set with an interstitial gap for interventional nuclear magnetic resonance applications

The introduction of more open magnet geometries in Magnetic Resonance Imaging (MRI) system calls for the design of new gradient coils with similar shape as the corresponding main magnet. In this paper, a novel technique for designing minimum inductance gradient coils with an interstitial gap which is suitable for a cylindrical open magnet structure with two separated gaps is presented. Design examples are given for the axial and the transverse gradient coils. A comparison between the gap size and the stored magnetic energy for the same gradient strength indicates a near-quadratic relationship between these two quantities.