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

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1907
Author(s):  
Imam Sapuan ◽  
Moh Yasin ◽  
Khusnul Ain ◽  
Retna Apsari
Keyword(s):  
Electrical Impedance ◽  
Current Source ◽  
Electric Impedance ◽  
Back Projection ◽  
Impedance Tomography ◽  
Tissue Impedance ◽  
Low Contrast ◽  
Capacitive Reactance ◽  
Phase Data ◽  
Linear Back Projection

This research offers a method for separating the components of tissue impedance, namely resistance and capacitive reactance. Two objects that have similar impedance or low contrast can be improved through separating the real and imaginary images. This method requires an Electrical Impedance Tomography (EIT) device. EIT can obtain potential data and the phase angle between the current and the potential measured. In the future, the device is very suitable for imaging organs in the thorax and abdomen that have the same impedance but different resistance and capacitive reactance. This device consists of programmable generators, Voltage Controlled Current Source (VCCS), mulptiplexer-demultiplexer potential meters, and phase meters. Data collecting was done by employing neighboring, while reconstruction was used the linear back-projection method from two different data frequencies, namely 10 kHz and 100 kHz. Phantom used in this experiment consists of distillated water and a carrot as an anomaly. Potential and phase data from the device is reconstructed to produce impedance, real, and imaginary images. Image analysis is performed by comparing the three images to the phantom. The experimental results show that the device is reliable.

Current source design for electrical impedance tomography

2003 ◽  
Vol 24 (2) ◽  
pp. 509-516 ◽  
Author(s):  
Alexander S Ross ◽  
G J Saulnier ◽  
J C Newell ◽  
D Isaacson
Keyword(s):  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Current Source ◽  
Impedance Tomography

AN EXPERIMENTAL ANALYSIS AND VALIDATION OF ELECTRICAL IMPEDANCE TOMOGRAPHY TECHNIQUE FOR MEDICAL OR INDUSTRIAL APPLICATION

2019 ◽  
Vol 31 (02) ◽  
pp. 1950010 ◽  
Author(s):  
Ramesh Kumar ◽  
Sharvan Kumar ◽  
A. Sengupta
Keyword(s):  
Current Pulse ◽  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Imaging Modality ◽  
Current Source ◽  
Control Unit ◽  
Tikhonov Regularization Method ◽  
Impedance Tomography ◽  
Cross Sectional ◽  
On Chip

Electrical impedance tomography is a recently established technique by which impedance of an object (medical or nonmedical applications) is measured data from the surface of the object, and a numerically simulated reconstruction of the object internal shape of the image can be obtained. This imaging technique based on boundary or surface voltage is measured when the different current pattern is injected into it. For current pulse, we are creating a voltage controlled current source, which is based on the different RC circuits, according to current amplitude and frequency values. The current source used in inject the current pulse of the various phantoms. The current position and measuring voltage is controlled by the created control unit or programmable system on chip (PSOC) of the proposed EIT system. After that image reconstruction of the cross-sectional image of resistivity requires sufficient data collection from used phantoms, which is based on finite element method (FEM) method and Tikhonov regularization method with helps of graphical user interface (GUI) on MatLab. The objective of the GUI was to produce an image (2D/3D), impedance distribution graph, and the FEM mesh model according to used electrode combinations from the various phantoms. EIT system has a great potential for imaging modality, is non-invasive, radiation-free, and inexpensive for medical applications.

Design and Validation of a New Programmable Current Source for Electrical Impedance Tomography Applications

2019 ◽  
Vol 17 (9) ◽  
pp. 688-695
Author(s):  
Ramesh Kumar ◽  
Sharvan Kumar ◽  
A. Sengupta
Keyword(s):  
Image Reconstruction ◽  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Current Source ◽  
Reconstruction Algorithm ◽  
Simulation Software ◽  
Constant Current ◽  
Impedance Tomography ◽  
Constant Current Source ◽  
Wide Range

This paper proposed an advanced digital voltage-controlled multi-frequency based constant current source, which is a wide range of loads and high SNR ratio for Electrical Impedance Tomography (EIT) application. In EIT a constant current source is required for injecting a sinusoidal current pulse to the phantom boundary. The boundary potentials are measured by inserting content current from the phantom boundary according to the variation in frequency and current levels. For studying the wide range of tissue conductivity among different type of subjects (the multi-frequency scanning) is desired in medical Electrical impedance tomography. The proposed Current source, which shows that the simulation has good performance at multi-frequency range with accuracy and stability. In proteus simulation software, the results show that the proposed circuit presents a more stable impedance output and the obtained boundary data at multi-frequency for the validation of the obtained data has been shown using suitable image reconstruction algorithm and is found suitable for image reconstruction much easier.

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