Nevzat G Gençer and I Oguz Tanzer 1999 Phys. Med. Biol. 44 2275 doi:10.1088/0031-9155/44/9/314
Nevzat G Gençer and I Oguz Tanzer
Show affiliationsRepresentations of the active cell populations on the cortical surface via electric and magnetic measurements are known as electromagnetic source images (EMSIs) of the human brain. Numerical solution of the potential and magnetic fields for a given electrical source distribution in the human brain is an essential part of electromagnetic source imaging. In this study, the performance of the boundary element method (BEM) is explored with different surface element types. A new BEM formulation is derived that makes use of isoparametric linear, quadratic or cubic elements. The surface integration is performed with Gauss quadrature. The potential fields are solved assuming a concentric three-shell model of the human head for a tangential dipole at different locations. In order to achieve 2% accuracy in potential solutions, the number of quadratic elements is of the order of hundreds. However, with linear elements, this number is of the order of ten thousand. The relative difference measures (RDMs) are obtained for the numerical models that use different element types. The numerical models that employ quadratic and cubic element types provide superior performance over linear elements in terms of accuracy in solutions. Assuming a homogeneous sphere model of the head, the RDMs are also obtained for the three components (radial and tangential) of the magnetic fields. The RDMs obtained for the tangential fields are, in general, much higher than those obtained for the radial fields. Both quadratic and cubic elements provide superior performance compared with linear elements for a wide range of dipole locations.
87.50.C- Static and low-frequency electric and magnetic fields effects
02.60.Lj Ordinary and partial differential equations; boundary value problems
87.19.R- Mechanical and electrical properties of tissues and organs
Issue 9 (September 1999)
Received 10 August 1998, in final form 30 March 1999
Nevzat G Gençer and I Oguz Tanzer 1999 Phys. Med. Biol. 44 2275
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N B Backhouse and P Gard 1974 J. Phys. A: Math. Nucl. Gen. 7 2101
Francesca Pennecchi and Luca Callegaro 2007 Metrologia 44 104
Daniela Calvetti et al 2006 Inverse Problems 22 1797
Gwyn P Williams 2006 Rep. Prog. Phys. 69 301
Aleksei M Upornikov 1994 Class. Quantum Grav. 11 2085
Luis Peralta et al 2008 Eur. J. Phys. 29 901
John Davey et al JHEP11(2009)028
Jorge A Horas et al 2005 Phys. Med. Biol. 50 1689