scholarly journals A Study of Magnetic Induction Tomography (MIT) for Calcium Oxalate Renal Screening

2021 ◽  
Vol 17 (4) ◽  
pp. 485-494
Author(s):  
Thompson Paulus ◽  
Nur Amira Zulkiflli ◽  
Fatin Aliah Phang Abdullah ◽  
Azli Yahya ◽  
Siti Zarina Abdul Muji ◽  
...  

Nephrolithiasis is a process of stone formation in the kidney by crystallization. The increasing prevalence of nephrolithiasis from time to time had sought an alternative from the conventional imaging techniques that is invasive, radiative, and non-rapid usage. This paper enclosed a design simulation study of Magnetic Induction Tomography (MIT) system using COMSOL Multiphysics for renal imaging. MIT is a soft field tomography and non-contact imaging modality which can project the passive electromagnetic properties (conductivity, permittivity and permeability) under the principle of electromagnetic induction. In this research also, 8 copper trans-receiver coils were employed in the MIT system and fixed by the insulation belt. Meanwhile, geometric set-up of renal organ was set to imitate the transverse section of human renal. In the methodology, sensor performance analyses were done using frequency ranging from 50 kHz to 2 MHz of the MIT system on radii of calcium oxalate in renal. The sensor response and pattern is discussed in this paper.

Author(s):  
Nurfarahin Ishak ◽  
Chua King Lee ◽  
Siti Zarina Mohd Muji ◽  
Abdul Azlin Bin Abdul Latip

Magnetic induction tomography (MIT) is an imaging modality focused on tracing the transmission of electrical conductivity within the body. This technique used to image electromagnetic properties of an object by using the eddy current effect. This paper explains the primary analog transceiver circuit of MIT. This is a surrogate design of the analog system in the electronic components for pattern recognition and conditioning. This MIT system operating with a single excitation signal frequency at 10MHz. The input voltage received by the receiver sensor would become the circuit input which contained information. The four stages process in the receiver circuit successfully captured the signal from the transmitter. These subsystems have their functions and can be put into effect in many ways. Therefore, the circuit was used to be reliable at agarwood samples. The approach transceiver circuit were successful and functional for MIT coil sensing. The input voltage feedback depending on the conductivity of the samples. As the dielectric properties of samples are high, the input voltage at the receiver also high. Therefore, 10MHz can use for agriculture while this range of frequency is usually used in biomedical applications. Series – parallel circuit gives a greater induction factor and therefore more induced voltage for the load of the receiver.


2013 ◽  
Vol 749 ◽  
pp. 371-376
Author(s):  
Yang Xuan ◽  
Xu Wang ◽  
Cheng An Liu ◽  
Dan Yang

Magnetic induction tomography (MIT) is a noninvasive and contactless imaging modality which aims at the reconstruction of the electrical conductivity in objects from alternating magnetic fields. Filtered back projection reconstruction algorithm is widely used in biomedical imaging field, and tried to use in MIT. Finite element analysis model has been established based on Scharfetter coil-coil model and perturbation theory, then simulated coaxial coil system by ANSYS software, the perturbation aroused by a target object moving on vertical coil axis. The sensitivity of a target object moves in vacuum and a salt solution were calculated respectively, the characteristics of the perturbation sensitivity in a salt solution were analyzed. The conditions of filtered back projection reconstruction algorithm in MIT were discussed.


Author(s):  
Nurfarahin Ishak ◽  
Chua King Lee ◽  
Siti Zarina Mohd Muji

Magnetic induction tomography is an imaging technique used to image electromagnetic properties of an object by using the eddy current effect. (MIT) is a non-destructive method that greatly is used in the agriculture industry. This method provided an opportunity to improve the quality of agricultural products. MIT simulation was used for agarwood existence detection. This paper presented for the simulation system contains 7 channel coils receiver and a channel transmitter which is a sensing detector. This experiment aims to demonstrate the reaction of induced current density and magnetic field at 10 MHz frequency. Then, it also determines the optimal solenoid coil to be used for a better outcome for the magnetic induction system. The simulation result shows that coil diameter, coil length, and coil layer have a crucial role in the great performance of the induced current and magnetic field. The more coil turns, the greater the strength of the permanent magnetic field around the solenoid coil. The result of the simulation is important and needs to be considered to verify the effectiveness of the system for developing the magnetic induction circuit design.


Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1306
Author(s):  
Martin Klein ◽  
Daniel Erni ◽  
Dirk Rueter

Magnetic induction tomography (MIT) is a contactless technique that is used to image the distribution of passive electromagnetic properties inside a voluminous body. However, the central area sensitivity (CAS) of this method is critically weak and blurred for a low conductive volume. This article analyzes this challenging issue, which inhibits even faint imaging of the central interior region of a body, and it suggests a remedy. The problem is expounded via two-dimensional (2D) and three-dimensional (3D) eddy current simulations with different transmitter geometries. On this basis, it is shown that a spatially undulating exciter coil can significantly improve the CAS by >20 dB. Consequently, the central region inside a low conductive voluminous object becomes clearly detectable above the noise floor, a fact which is also confirmed by practical measurements. The improved sensitivity map of the new arrangement is compared with maps of more typical circular MIT geometries. In conclusion, 3D MIT reconstructions are presented, and for the same incidence of noise, their performance is much better with the suggested improvement than that with a circular setup.


Author(s):  
Beata Szuflitowska ◽  
Marcin Ziolkowski ◽  
Krzysztof Stawicki

Magnetic Induction Tomography (MIT) belongs to the noncontact electromagnetic imaging techniques. This paper focuses on determination of a secondary magnetic field map calculated with the help of the Biot-Savart law around the low-conductivity object. The inclusions of various shapes and different electrical conductivities values and two measurement planes are considered. In each case the objects’ single maximal cell volume with assumed uniform eddy current density has been determined. In order to keep the relative error below 1% the object should be divided in most cases into elements with maximal cell volume equal to 0.244 mm3 for yz − plane, and 0.03 mm3 for xy − plane.


2019 ◽  
Vol 61 (3) ◽  
pp. 255-259
Author(s):  
Lipan Zhang ◽  
Qifeng Meng ◽  
Kai Song ◽  
Ming Gao ◽  
Zhiyuan Cheng

Author(s):  
Jingwen Wang ◽  
Xu Wang ◽  
Dan Yang ◽  
Kaiyang Wang

Background: Image reconstruction of magnetic induction tomography (MIT) is a typical ill-posed inverse problem, which means that the measurements are always far from enough. Thus, MIT image reconstruction results using conventional algorithms such as linear back projection and Landweber often suffer from limitations such as low resolution and blurred edges. Methods: In this paper, based on the recent finite rate of innovation (FRI) framework, a novel image reconstruction method with MIT system is presented. Results: This is achieved through modeling and sampling the MIT signals in FRI framework, resulting in a few new measurements, namely, fourier coefficients. Because each new measurement contains all the pixel position and conductivity information of the dense phase medium, the illposed inverse problem can be improved, by rebuilding the MIT measurement equation with the measurement voltage and the new measurements. Finally, a sparsity-based signal reconstruction algorithm is presented to reconstruct the original MIT image signal, by solving this new measurement equation. Conclusion: Experiments show that the proposed method has better indicators such as image error and correlation coefficient. Therefore, it is a kind of MIT image reconstruction method with high accuracy.


Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1063
Author(s):  
Antonella Castellano ◽  
Michele Bailo ◽  
Francesco Cicone ◽  
Luciano Carideo ◽  
Natale Quartuccio ◽  
...  

The accuracy of target delineation in radiation treatment (RT) planning of cerebral gliomas is crucial to achieve high tumor control, while minimizing treatment-related toxicity. Conventional magnetic resonance imaging (MRI), including contrast-enhanced T1-weighted and fluid-attenuated inversion recovery (FLAIR) sequences, represents the current standard imaging modality for target volume delineation of gliomas. However, conventional sequences have limited capability to discriminate treatment-related changes from viable tumors, owing to the low specificity of increased blood-brain barrier permeability and peritumoral edema. Advanced physiology-based MRI techniques, such as MR spectroscopy, diffusion MRI and perfusion MRI, have been developed for the biological characterization of gliomas and may circumvent these limitations, providing additional metabolic, structural, and hemodynamic information for treatment planning and monitoring. Radionuclide imaging techniques, such as positron emission tomography (PET) with amino acid radiopharmaceuticals, are also increasingly used in the workup of primary brain tumors, and their integration in RT planning is being evaluated in specialized centers. This review focuses on the basic principles and clinical results of advanced MRI and PET imaging techniques that have promise as a complement to RT planning of gliomas.


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