A NEW DESIGN FOR A 3-CHANNEL SURFACE GRADIENT COIL EMPLOYING A 3-DIMENSIONAL FINITE-ELEMENT MODEL

A new design of a three-channel surface gradient coil (SGC) is present ed. The optimal objective of this design is to minimize parasitic fiel d 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 ind icate improved field behaviors when compared with those of a previousl y reported SGC designed by Cho and Yi (J. Magn. Reson. 94, 471-485 (19 91)). To confirm the predicted improvement, two G(y) (y-axis) gradient coils, based on the old and new designs, have been constructed and in stalled in a General Electric CSI 2 Tesla MRI system with a 15-cm bore . Based on the resulting MR images, the new gradient coil configuratio n provides more uniform field gradients and less parasitic field gradi ents, which results in higher quality images than the previously repor ted SGC design. This paper also demonstrates the remarkable accuracy o f the 3D FE simulation model.