In this article, we describe modelling of an advanced system of electrical tomography for biomedical applications. The collection of tomographic data must be as fast as reliable, in order to take into account the algorithms of reversing the tomography with almost real-time update. To provide a high-level application programming interface using standard communication protocols and execute user-level programs. System architecture and prototype designs for biomedical electrical tomography are presented. Details of the implementation are explained for two prototype devices: a separate FPGA / microcontroller chip and a hardware microprocessor containing a system that contains a microprocessor, peripherals and an FPGA system. The algorithms of electrical reconstruction of impedance tomography have been tested. New results of the reconstruction of the numerically simulated phantom were presented. The calculations were made for the defined model by solving the inverse problem.
Słowa kluczowe: Electrical Tomography; Image Reconstruction; Biomedical Signals.
In this article, we describe modelling of an advanced system of electrical tomography for biomedical applications. The collection of tomographic data must be as fast as reliable, in order to take into account the algorithms of reversing the tomography with almost real-time update. To provide a high-level application programming interface using standard communication protocols and execute user-level programs. System architecture and prototype designs for biomedical electrical tomography are presented. Details of the implementation are explained for two prototype devices: a separate FPGA / microcontroller chip and a hardware microprocessor containing a system that contains a microprocessor, peripherals and an FPGA system. The algorithms of electrical reconstruction of impedance tomography have been tested. New results of the reconstruction of the numerically simulated phantom were presented.
Keywords: tomografia elektryczna; rekonstrukcja obrazu, sygnały biomedyczne.
The platform consists of a data collection device and an aggregation and processing mechanism to generate useful information for diagnosis or for initial monitoring of physiological changes in the body [2-6,13-18]. The tomographic platform will enable the monitoring of physiological processes using the observed changes in electrical conductivity. Considering surface and subsurface information and using hybrid algorithms, new insights can be explored more closely, for example: physiological changes can be related to a specific pathology, the patient's health status can be estimated or a more accurate assessment of drug therapy effects can be provided. The information generated by the platform will be used in diagnostics in order to facilitate the interpretation of patients' medical condition [1.7-12]. Electrical tomography (ET) for biomedical purposes presents structural differences in the general electrical impedance tomography (gpEIT): Strengthening is limited by international medical standards regarding current level and frequency. In gpEIT, the current and frequency can be as high as devices and region of interest (ROI) can resist. The impression should be transferred with the help of electrodes on the surface of the skin. In gpEIT, the electrodes can be inserted into the ROI or ROI area and can be immersed in an EIT tank filled with electrolytic fluid. The stimulation / sensing of data collection and tomographic reversal must be as fast as possible to ensure visualization of the monitored patient in real time. In gpEIT, fast data acquisition and real-time visualization are optional. Biological soft / hard tissue is a complex multi-scale matter (colloids -> cells -> tissues -> organs -> body). In gpEIT ROI is often made of simple materials. The rhythm and dynamics of the human body modify the surface / volume of organs, e.g. in the case of lung or heartbeat monitoring, but [...]
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