Anatomically Constrained Conductivity Estimation of the Human Head Tissues in Vivo: Computational Procedure and Preliminary Experiments

We have shown that using parameterized EIT measurements procedure and realistically shaped highresolution finite difference models (FDM) of the human head based on the subject specific co-registered CT and MRI scans, it was possible to extract up to 13 head tissues conductivities in simulations with synthetic data. We have used the multi-start downhill simplex and simulated annealing algorithms depending on the number of unknowns in inverse search. The procedure describes parcellation of a skull into 10–12 anatomically relevant bone plates and provides the skull conductivity inhomogeneities information in the forward solver for the EEG inverse problem. The preliminary results of the first experiments performed on a human subject are also reported.

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