Investigation of coil designs for transcranial magnetic stimulation on realistic head model

This paper shows simulation results of transcranial magnetic stimulation (TMS) for three different coils including Fo8 (figure of eight) coil, V-shape coil, and butterfly coil. Considering the clinical applications the feasibility of three different coils in TMS is analyzed. An electromagnetic software of Xfdtd which employ impedance method is used to obtain three dimensional distribution of electric field, magnetic field in the realistic head model. This study conducting with realistic head model offers actual penetration depth, focality, and biocompatibility which are not possible with homogeneous head model used in some existing works. Among the three proposed coils, the Fo8 coil has greater induced electric field and magnetic field than other two coils (Butterfly and V shape coil respectively).