Fast in vivo measurements of local tissue impedances using needle electrodes.

The objective of the research is to show an in vivo, fast method of measurement of local tissue bio-impedance in the beta dispersion region (0-200 kHz). A needle electrode is used for the purpose. The performances with respect to circuits, electrodes, measurement area and electrical representations are evaluated. A measurement example is shown, and the electrical representations are discussed and compared using it. The method discussed, although invasive, is considered to be useful for local tissue diagnoses concerning structures and physiological functions.