Research On Hardware System Of The Breast EIT

Electrical Impedance Tomography (EIT) is one of the important research topics in biomedical engineering area nowadays, it possesses advantages of functional imaging, noninvasive and medical image monitoring. This paper studied the practical application technology of the breast EIT detection system based on comprehensive analysis of the developments and existing problems for the breast EIT detection technology both domestic and international. Based on the characteristics of breast detection, this paper proposed a design of integration multi-pattern detection system for the development of EIT breast detection forward to the clinical application. Main tasks have completed in this paper are as follows:This paper used the method which combines mechanical switches with analog switches to achieve a high precision and multi-pattern 16 electrodes EIT hardware system. The whole system include the design and realization of control and sampling circuit, constant current source, stimulation and measurement pattern selection, electrode array, analog signal processing, USB communication and so on. The system is flexible and has a strong expansion characteristic. Preliminary results show that the system developed in the paper meets the expected design requirements.Software engineering design ideas and methods are applied to the firmware of the hardware system, and this will enable the development of procedures of the EIT breast system more standardized. A multi-pattern firmware research platform with good scalability has also developed in the paper.Software FEMLAB is used to simulate the multi-pattern detection methods. The combination of image processing and evaluation function is used to evaluate the reconstructed images of EIT and to study impact rule of detection pattern changes on the image results.Finally, some suggestions about the clinical EIT breast detection in the future have given out.