Optimizing of electrode system with central object in electrical impedance tomography

Electrical impedance tomography (EIT) is one of the important research topics in today´s biomedical engineering. EIT system applies currents through electrodes attached to the surface of the human body and measures the resulting voltages to reconstruct and display approximate pictures of the electric conductivity and permittivity inside the body. Electrode lies in the front of the whole EIT system and contacts with human body directly. It is one of the most sensitive and the pivotal parts of EIT system. The type and the configuration of electrode system influence the reconstruction image greatly, especially for the central area, the deep area of body, where the measurement sensitivity is very low. A simulation platform is developed in the paper to optimize design of the electrode structure parameter based on the coercive equipotential nodes model for the imaging object of central area, the deep area of body. The influences of the different object depths on the measurement sensitivity and the image reconstruction quality have studied by using different electrode types and configurations. The simulation results suggest that optimal selection of electrode types and configurations can helpfully increase the image quality and measurement sensitivity of the image with deeper object. Several type and configuration parameter of EIT electrode that fit for imaging deeper object are also presented.