Application of Electrical Impedance Tomography in Diagnosis of Cancer

Abstract

Electrical impedance tomography (EIT), a new imaging technique, is cost-effective, portable, and radiation-free, which makes it a suitable tool for bedside diagnosis. This review aims to provide recent development in EIT application in detection of various types of cancer. EIT calculates the internal electrical conductivity distribution of an organ by measuring its surface impedance. Electrodes are placed on the surface of the target tissue, and small alternating currents are injected and then related voltages are observed and analyzed. The electrical permittivity and conductivity are reconstructed by measuring the electrode voltages. The electrical characteristic of biological tissues is remarkably dependent on their structures. Some malignancies have different properties and can be distinguished using EIT. These differences are attributed to changes in cellular water content, membrane properties, destruction of tight junctions with cell membranes, and changes in the orientation of malignant cells. However, EIT can distinguish between human tumors and healthy cells in different types of organs.