Researches On Impedance Measurement System Used For Foci Edge Detection Of Breast Cancer

Bi-impedance spectroscopy characteristics carry so much pathology and physiological information. Any pathological phenomena and physiological activity will cause the change of human tissue impedance. The Bio-Impedance Measuring Technology in early diagnosis and foci edge detection of breast cancer is easy to accept and has wide development prospects. It has the advantages of low-cost, noninvasive, safe and fast, so that it has been analyzed by many scholars for a few of years.In the past research work, our group had optimized the measurement electrode and the measurement methods and done a lot work on distinguishing the breast tissues. A very good result had been obtained by extracting different characteristic parameters.Based on the past research work, this paper did further analysis on the frequency range which can meet the requirements of parameter extraction. An impedance measurement system used for foci edge detection of breast cancer was established. It can complete the task of impedance measurement and distinguish the breast tissues fast and accurately.Hardware system in this paper used the way of modular design, which includes signal source module, signal demodulation module, data acquisition module and measurement module. Compensation and calibration had been done to every module. The synchronous coordination between the signal source module and the data acquisition module was controlled by computer.With reference to the practice of Morimoto and Heinitz, three components model was established. The impedance measurement results were compared between the system designed in this paper and Agilent4294A precision impedance measuring instrument. Further analysis had been done to extract characteristic parameters. Although there are some errors, measurement results of the system can track the trend of every model. The characteristic parameters can be extracted accurately according to the measurement results. At last, the sensitivity of the system was validated through the impedance measurement of pork.