3D simulation of EIT for monitoring impedance variations within the human head

Abstract

A preliminary analysis is presented concerning the use of EIT for detecting impedance inhomogeneities within the human brain. The work to date is centred around the monitoring of two distinct impedance variations: those associated with the application of a carotid clamp during surgery and changes caused by the redistribution of blood flow during auditory stimuli. Using the commercially available Ansoft Maxwell package, a 3D finite element model of the human head has been developed to solve the forward problem. The model is hemispherical in shape and comprises regions of brain, cerebrospinal fluid, skull and skin and includes 16 scalp electrodes each of area 1 cm2. Results from simulations using the model suggest that an EIT system, incorporating diametric current excitation, would require a voltage measurement sensitivity of 100-120 dB in order to detect the impedance variations in the above cases.

The Impact of EEG/MEG Signal Processing and Modeling in the Diagnostic and Management of Epilepsy

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Krylov subspace iterative techniques: on the detection of brain activity with electrical impedance tomography

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Use of 3-D magnetic resonance electrical impedance tomography in detecting human cerebral stroke: a simulation study

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