Anomaly Detection Using Electric Impedance Tomography Based on Real and Imaginary Images

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Electrical Engineering

Background:

• Tissue impedance analysis is crucial for medical imaging.
• Distinguishing between resistance and capacitive reactance can improve image contrast.
• Electrical Impedance Tomography (EIT) offers a non-invasive imaging modality.

Purpose of the Study:

• To develop and validate a method for separating tissue resistance and capacitive reactance using EIT.
• To improve image quality for objects with similar overall impedance but differing component values.
• To demonstrate the potential of this method for imaging thoracic and abdominal organs.

Main Methods:

• Utilized an Electrical Impedance Tomography (EIT) device with programmable generators, VCCS, multiplexer-demultiplexer, and phase meters.
• Collected potential and phase angle data at 10 kHz and 100 kHz using neighboring data acquisition.
• Reconstructed impedance, real (resistance), and imaginary (capacitive reactance) images via linear back-projection.

Main Results:

• The developed EIT method successfully separated resistance and capacitive reactance components.
• Reconstructed impedance, real, and imaginary images were analyzed against a phantom (distilled water with a carrot anomaly).
• Experimental results confirmed the reliability of the EIT device and the separation method.

Conclusions:

• The proposed method effectively separates tissue resistance and capacitive reactance, enhancing image contrast.
• This EIT-based approach shows significant promise for improved non-invasive imaging of organs with similar impedance.
• The validated device and method offer a reliable tool for future biomedical imaging applications.