A Bilateral Constrained Image Reconstruction Method Using Electrical Impedance Tomography and Ultrasonic Measurement

Abstract

Electrical Impedance Tomography (EIT) reconstructs the conductivity distribution in a sensing area through an array of boundary electrodes and has received increasing attention in bio-impedance measurement. To provide accurate image reconstruction of irregular conductivity distribution in large sensing area, we propose an efficient and accurate bilateral constrained dual modality reconstruction algorithm using EIT and ultrasonic measurement, where the EIT pre-reconstruction helps to select the time of flight (TOF) time window and the ultrasound reflection information of boundary points contributes to joint iterative reconstruction. In the simulations and phantom experiments selecting abdomen tumor as the object of interest, the proposed method successfully reconstructed the small inclusions. Quantitatively, the proposed bilateral constrained method has improved the reconstruction performance in terms of boundary preservation and robustness compared with single modality EIT and ultrasonic algorithms.