3-D optimal shape design of ferromagnetic pole in MRI magnet of open permanent-magnet type

This paper presents 3-D optimal shape design method of ferromagnetic pole pieces for magnetic resonance imaging (MRI) devices of open permanent magnet type. The design method is based on a continuum sensitivity analysis in conjunction with the boundary integral equation method (BIEM). The magnetic poles of an open magnet assembly are designed by the proposed method and the conventional shimming method. Magnetic field strength, ppm order homogeneity and working space volume are compared between the proposed method and conventional one.