A new design for a three-channel surface gradient coil employing a three-dimensional finite element model.

A new design of a three-channel surface gradient coil (SGC) is presented. The optimal objective of this design is to minimize parasitic field gradients by modifying the wire arrangement in the individual coils. A 3D finite element (FE) model is employed to analyze the SGC's field predictions. The numerical analysis results of the new SGC design indicate improved field behaviors when compared with those of a previously reported SGC designed by Cho and Yi (J. Magn. Reson. 94, 471-485 (1991)). To confirm the predicted improvement, two Gy (Y-axis) gradient coils, based on the old and new designs, have been constructed and installed in a General Electric CSI 2 Tesla MRI system with a 15-cm bore. Based on the resulting MR images, the new gradient coil configuration provides more uniform field gradients and less parasitic field gradients, which results in higher quality images than the previously reported SGC design. This paper also demonstrates the remarkable accuracy of the 3D FE simulation model.