1 July 1990 Volume currents in biomagnetic imaging
Author Affiliations +
Abstract
In biomagnetic imaging, the magnetic field caused by electrical nerve impulses is measured and used to form an estimate of the location and strength of the impulse. One complicating factor in forming this estimate is the fact that the impulses induce current flow in the volume conductor surrounding the nerve.17 In this presentation we explore the properties of these volume currents. We first formulate the problem in the standard form using Ohm's law to relate the volume current to the impressed (nerve impulse) current and the conductivity distribution. We then depart from the usual derivation by making use of properties of the fourier-transformed maxwell8 and continuity equations. In fourier space, the divergence operation in a vector field becomes a simple taking of the radial component of the fourier-transformed field; the curl transforms into taking tangential components. By decomposing the current densities and using the maxwell equations, we are able to arrive at a recursive differential expression for the volume-current generated magnetic field. The driving term in the expression is the current due to the divergence of the impressed current density. We provide some examples of applying this expression to simply shaped conductors.
© (1990) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
William J. Dallas, "Volume currents in biomagnetic imaging", Proc. SPIE 1231, Medical Imaging IV: Image Formation, (1 July 1990); doi: 10.1117/12.18777; https://doi.org/10.1117/12.18777
PROCEEDINGS
5 PAGES


SHARE
RELATED CONTENT

Applications of GGF method in analysis of ferromagnets
Proceedings of SPIE (November 29 2000)
The Pseudo-Maxwell Equations Revisited
Proceedings of SPIE (February 26 1982)
Two- and three-dimensional views of biomagnetic imaging
Proceedings of SPIE (June 01 1992)
Biomagnetic Imaging Using Arrays Of SQUIDs
Proceedings of SPIE (May 01 1989)

Back to Top