Evaluation of fast time-domain based impedance measurements on biological tissue

Bio-impedance measurements are widely used for characterization of biological objects. Although the measured impedance of such objects is independent of the measurement method used, slight differences between measurements in the frequency and time domain are found. For many practical applications time domain based measurements are advantageous, but they are often rejected as not accurate. In order to show their suitability for bio-impedance measurements we used a special arrangement of time domain and frequency domain based measurements at the same biological specimen (canine liver) with the same electrodes. A reasonable coincidence in the measurement results could be shown. Moreover we used only a fraction of the time domain measurement data in order to demonstrate a significant reduction in measurement time while maintaining a reasonable accuracy. An algorithm for fast processing of the time domain data without transformation into the frequency domain is provided.