Contactless impedance measurement by magnetic induction--a possible method for investigation of brain impedance.

Abstract:

:Using a primary coil that induces eddy currents in a volume conductor, and a pair of secondary coils configured to form a differential transformer, it is possible to measure the conductivity of a volume conductor by the magnetic fields of the induced eddy currents. This method is especially favourable for measuring impedance of the brain, as the low conductance of the surrounding skull interferes only very slightly with the measuring process. In a simulation experiment a life-size skull model was filled with NaCl solutions of different concentrations in each half, so as to model the impedances of a normal and an oedematous hemisphere. The impedance differences could be clearly detected by a coil system of 25 mm diameter.

journal_name

Physiol Meas

authors

Netz J,Forner E,Haagemann S

doi

10.1088/0967-3334/14/4/007

subject

Has Abstract

pub_date

1993-11-01 00:00:00

pages

463-71

issue

4

eissn

0967-3334

issn

1361-6579

journal_volume

14

pub_type

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