Ersahin A, Bronskill M J, Henkelman R M, Collick B, Hinks R S
Department of Medical Biophysics, University of Toronto, Sunnybrook Health Science Centre, Imaging Research, Canada.
J Magn Reson Imaging. 1998 Sep-Oct;8(5):1145-53. doi: 10.1002/jmri.1880080521.
The requirements for access and imaging performance compete in the design of open-concept MR magnets and gradient coils. We conducted a theoretical and experimental investigation of gradient coil design using both solid and laminated pole piece construction to determine whether adequate eddy current control can be obtained without shielded gradient coils while maintaining good patient access and high gradient performance. Eddy currents, gradient characteristics, gradient efficiency, and magnet openness are compared and contrasted for various construction options based on a compact, .27 T iron yoke magnet. The resulting pole pieces and gradient coils have high efficiency for an interventional open-configuration magnet while taking up minimal space between the poles for improved patient access.
在开放式磁共振成像（MR）磁体和梯度线圈的设计中，对可达性和成像性能的要求相互矛盾。我们对采用实心和叠片式极靴结构的梯度线圈设计进行了理论和实验研究，以确定在不使用屏蔽梯度线圈的情况下，能否在保持良好的患者可达性和高梯度性能的同时，实现足够的涡流控制。基于一个紧凑的0.27T铁轭磁体，对各种结构方案的涡流、梯度特性、梯度效率和磁体开放性进行了比较和对比。最终得到的极靴和梯度线圈对于介入式开放配置磁体具有高效率，同时在极间占用的空间最小，从而改善了患者可达性。
