Finite element simulation of the impedance response of a vascular segment as a function of changes in electrode configuration

Abstract

Monitoring a biological tissue as a three dimensional (3D) model is of high importance. Both the measurement technique and the measuring electrode play substantial roles in providing accurate 3D measurements. Bioimpedance spectroscopy has proven to be a noninvasive method providing the possibility of monitoring a 3D construct in a real time manner. On the other hand, advances in electrode fabrication has made it possible to use flexible electrodes with different configurations, which makes 3D measurements possible. However, designing an experimental measurement set-up for monitoring a 3D construct can be costly and time consuming and would require many tissue models. Finite element modeling methods provide a simple alternative for studying the performance of the electrode and the measurement set-up before starting with the experimental measurements. Therefore, in this study we employed the COMSOL Multiphysics finite element modeling method for simulating the effects of changing the electrode configuration on the impedance spectroscopy measurements of a venous segment. For this purpose, the simulations were performed for models with different electrode configurations. The simulation results provided us with the possibility of finding the optimal electrode configuration including the geometry, number and dimensions of the electrodes, which can be later employed in the experimental measurement set-up.

Fish Detection Using Electrical Impedance Spectroscopy

“…We used a four electrode configuration, with one CC and one PU electrode pair, with shapes and dimensions as in the experimental setup. For each voxel we calculated the sensitivity value, utilizing the principle of reciprocity ( [18], [25], [26]):…”

“…where − − → J CC • − − → J P U denotes a dot product of current density vectors induced by current flow I between CC and PU electrodes, respectively. The sensitivity S describes the contribution of resistivity of each voxel to the total measured impedance, which can be calculated using the following relation ( [18], [25], [26]):…”