[The use of impedance measurements in the colon]

Biological changes in tissue also affect its biophysical and consequently its electrical properties. By the method here described, high-frequency current is caused to flow through the tissue under examination and the voltage decrease is measured. Measuring equipment of the author's own design has been developed for routine use of the method. The results of repeated measurements in the rectum of 323 subjects show that malignant tumor always cause lesser voltage decreases than do intact or inflamed tissues. The method has already been used during coloscopy in 40 patients. The results were in full agreement with biopsy findings.