A boundary element approach to relate surface fields with the specific absorption rate (SAR) induced in 3-D human phantoms

This paper proposes a numerical technique, based on the boundary element method, for the reconstruction of the specific absorption rate in 3-D human phantoms. The method intends to relate electric and magnetic field measurements on the surfaces of a virtual box surrounding the considered phantom with the SAR values within the body. After a description of the adopted boundary element approach, an analysis of the influence on the SAR reconstruction accuracy of several parameters, such as size and shape of the virtual box, or position and number of the measurement points, is presented. The effect of the field source and supply frequency is also investigated. Finally, an extension of the approach to non-homogeneous phantoms is discussed.

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