Image reconstruction method in quasi-static electrical impedance imaging

Abstract

The invention discloses an image reconstruction method in quasi-static electrical impedance imaging. The image reconstruction method utilizes an electrical impedance imaging method. A to-be-tested object is excited under current excitation with frequency, namely f (omega1) and f (omega2) respective, boundary voltages, namely V' (omega1) and V' (omega 2) under the two times of current excitation are collected, and collected data undergo the process of weighting and difference calculating. A boundary voltage variation delta V caused by difference of impedance change of a target area excited by different frequency is calculated, and impedance distribution change delta Rho of the target area excited by different frequency is calculated. The impedance distribution change delta Rho of the target area excited by different frequency is utilized to reconstruct an electrical impedance tomography (EIT) image. According to the image reconstruction method in quasi-static electrical impedance imaging, before two groups of measured data with different frequency are used for imaging, affection of non-target information on a reconstruction result in an imaging area is considered, and a data processing manner of weighting and difference calculating is raised. Artifacts produced in a reconstructed image by the non-target information are effectively removed, target identification is improved, and quality of the reconstructed image is improved.

Description

technical field [0001] The invention belongs to the technical field of electrical impedance tomography, and relates to an image reconstruction method in quasi-static electrical impedance imaging. Background technique [0002] Electrical impedance tomography (electrical impedance tomography, EIT) is a new type of medical imaging technology. By applying a safe excitation current (voltage) to the human body and measuring the voltage (current) signal on the surface of the body at the same time, a certain level of the human body can be obtained through reconstruction. The distribution of impedance or impedance changes within a fault. [0003] Electrical impedance tomography can be divided into: static imaging (using the absolute value distribution of impedance as the imaging target) and dynamic imaging (taking the change of impedance as the imaging target). Due to the strict requirements on the data acquisition system of static imaging, it is limited in practical application and...

AI Technical Summary

Problems solved by technology

[0005] Each tissue of the human body has certain impedance spectrum characteristics, so the measurement data under different excitation frequencies not only contains information about lesions but also information about normal tissues, so the differential results of data at different frequencies contain a large amount of non-lesion tissue impedance Therefore, it will lead to a large number of artifacts in the reconstructed image, and even the lesion cannot be distinguished

Images