Electrical impedance tomography problem with inaccurately known boundary and contact impedances

In electrical impedance tomography (EIT) the conductivity function inside a body is reconstructed based on current and voltage data on the boundary of the body. The traditional setting for the EIT problem assumes that the boundary of the body and the electrode-skin contact impedances are known a priori. However, in clinical experiments one usually lacks the exact knowledge of the boundary and contact impedances, and it has been noticed that even small errors in the shape of the computation domain or contact impedances can cause large systematic artefacts in the reconstructed images. In this paper, we propose a novel reconstruction method in which the systematic errors caused by inaccurately known boundary and contact impedances are eliminated as part of the image reconstruction. The method is tested with real EIT data