Monotonicity-based Electrical Impedance Tomography Lung Imaging

This paper presents a monotonicity-based spatiotemporal conductivity imaging method for continuous regional lung monitoring using electrical impedance tomography(EIT). The EIT data (i.e., the boundary current-voltage data) can be decomposed into pulmonary, cardiac and other parts using their different periodic natures. The time-differential current-voltage operator corresponding to lung ventilation can be viewed as either semi-positive or semi-negative definite owing to monotonic conductivity changes within the lung region. We used this monotonicity constraint to improve the quality of lung EIT imaging. We tested the proposed method via numerical simulations and phantom experiments.