|
|
Effects of Shape Deformation of Figure\|Eight Coil on the Distribution of Space Mangnetic Fields and Induced Electric Fields in Magnetic Stimulation#br# |
1 School of Automation and Electrical Engineering Lanzhou Jiaotong University, Lanzhou 730070, China
2 Key Lab of Optoelectronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University Lanzhou 730070, China |
|
|
Abstract Although the focality of conventional figureofeight (fo8) coil is superior to that of round coil in transcranial magnetic stimulation, there still exists higher magnetic fields and induced electric fields near the outer rim of double wings of fo8 coil. In this paper, we presented a deformed figureofeight coil (Dfo8) by bending its two wings from the surface of the coil. The distribution of magnetic fields and the induced electric fields were calculated numerically, and the results were compared with those of conventional fo8. Results show that when the bending angle for Dfo8 was between 45 degree and 60 degree, the magnetic fields and the induced electric fields over the centre position of Dfo8 were about 90% of that of fo8, while the magnetic fields and the induced electric fields over the outer rim of Dfo8 were about 30% of that of fo8. It is indicated that the focality of the magnetic fields and the induced electric fields has been improved by Dfo8 coil, which provided a new method for designing the new transcranial magnetic stimulation coil.
|
|
|
|
|
[1]Barker AT, Jalinous R, Freeston IL. Noninvasive simulation of the human motor cortex [J]. The Lancet, 1985, 1(8437): 1106-1107.
[2]Berardelli A, Suppa A. Recent advances in the pathophysiology of parkinson’s disease:Evidence from fMRI and TMS studies [J]. Experimental Neurology, 2011, 227(1): 10-12.[3]Sampson SM, Solvason HB, Husain MM. Envisioning transcranial magnetic stimulation(TMS) as a clinical treatment option for depression [J]. Psychiatric Annals, 2007, 37(3): 189-196.
[4]Levkovitz Y, Sheer A, Harel EV, et al. Differential effects of deep TMS of the prefrontal cortex on apathy and depression [J]. Brain Stimulation, 2011, 23(6): 529-536.
[5]Ueno S, Tashiro T, Harada K. Localized stimulation of neural tissues in the brain by means of a paired configuration of timevarying magnetic fields [J]. J Appl Phys, 1988, 64(10): 5862-5864.
[6]殷涛,刘志朋. 脑磁刺激空间感应电场分布的数学模型与计算机仿真 [J].中国生物医学工程学报, 2004, 19(1): 62-66.
[7]刘国强,霍小林. 三层球模型经颅磁刺激感应电场研究 [J]. 中国生物医学工程学报, 2004, 23(1): 83-86.
[8]陈勇,徐桂芝,杨硕, 等. 经颅磁刺激线圈设计及分析 [J]. 华北电力大学学报,2005, 32(S1): 98-101.
[9]王品,郑小林. 磁刺激中脑内感应电场的计算 [J]. 中国生物医学工程学报, 2006, 25(1):74-78.
[10]蒲丽娜,殷涛,安好,等. 提高脑神经磁刺激感应电场聚焦性能的线圈参数优化方法的研究 [J]. 生物医学工程研究, 2008, 27(2): 74-78.
[11]刘翠,刘冀成. 经颅磁刺激下二维头部模型的磁场分布 [J]. 成都信息学院学报,2010, 25(5): 481-484.
[12]Lu M, Ueno S, Thorlin T, et al. Calculating the current density and electric field in human head by multichannel transcranial magnetic stimulation [J]. IEEE Trans Magnetics, 2009, 45(3): 1662-1665.
[13]Lu M, Ueno S, Thorlin T, et al. Calculating the activating function in the human brain by transcranial magnetic stimulation [J]. IEEE Transactions on Magnetics, 2008, 44(6): 1438-1441.
[14]冯慈璋,马西奎. 工程电磁场导论 [M]. 北京:高等教育出版社,2000, 92-94.
[15]Gershon AA, Dannon PB, Grunhaus L. Transcranial magnetic stimulation in the treatment of depression [J]. American Journal of Psychiatry, 2003, 160(5): 835-845.
[16]Orcutt N, Gandhi OP. A3D impedance method to calculation power deposition in biological bodies subjected to timevarying magneticfields [J]. IEEE Trans Biomedical Engineering, 1988, 35(8): 577-583.
[17]Lontis ER, Voigt M, Struijk JJ. Focality assessment in transcranial magnetic stimulation with double and cone coils [J]. Journal of Clinical Neurophysiology, 2006, 23(5): 462-471.
[18]Roth Y, Amir A, Levkovitz Y, et al. Threedimensional distribution of the electric field induced in the brain by transcranial magnetic stimulation using figure8 and deep Hcoils [J]. Journal of Clinical Neurophysiology, 2007, 24(1): 31-38.
[19]Ren C, Tarjan PP, Popovic DB. A novel electric design for electromagnetic stimulation—the Slinky coil [J]. IEEE Trans Biomedical Engineering, 1995, 42(9): 918-925.
[20]Ruohonen J, Ilmoniemi RJ. Focusing and targeting of magnetic brain stimulation using multiple coils [J]. Medical & Biological Engineering & Computing, 1998, 36(3): 297-301.[21]刘志朋,殷涛,关晓光. 一种抑制反向感应电场的磁刺激线圈设计方法探讨 [J]. 生物医学工程学杂志, 2003, 20(1):45-48. |
|
|
|