Test of the method of differentiation between healthy and anomalous breast tissues using the open-ended dielectric probe covered by a dielectric film

Abstract

Dielectric properties of breast tissue obtained from 131 patients were investigated by an open-ended probe separated from the tissue by a dielectric film (plastic foil). The film decreases the measured capacitance, but the content of blood and body liquids has little effect on the measured quantity. We found that in cancerous tissue the electric capacity (related to the permittivity) measured at f > or = 10 MHz using the modified probe is higher than that in normal tissue. The dielectric assignment was confirmed by histopathology in 94% of investigated cases. High efficiency in differentiation between normal and cancer breast tissues and the feasibility of fulfilling of aseptic conditions (a film covering the probe) are promising in intra-operative cancer diagnostics.

Modified open-ended dielectric probe in distinction between cancer and healthy breast tissues

“…It results in unrepeatable conditions of measurements making the diagnostic application of the dielectric method very difficult. To overcome these problems we propose blocking of the electrodes by using a non-conducting layer separating the tissue and the probe [6].…”

Dielectric-technique-assisted breast cancer surgery

“…The physics back- ground of the measurements and the tests carried out on reference substances and animal tissue have been described in earlier publications from physics journals [18][19][20].…”

“…Laboratory testing has demonstrated that cancer tissue can be detected both on the surface of a specimen as well as underneath a 1-2 mm layer of healthy breast tissue [18,19].…”

“…Laboratory testing has demonstrated such differences in clean and dried samples [17][18][19], however in real-life situations the presence of blood and serum interferes with such measurements by apparently increasing the permittivity and conductivity in normal tissue to those levels found in malignant tissue. For this reason the method is problematic for use during surgery [21,22].…”

“…This study demonstrates the use of a probe with socalled blocked electrodes, where the electric sensor does not come into direct contact with the examined tissue but is separated by a thin layer of insulation (polyethylene film) [18][19][20] thus avoiding the conflicting interference from blood and serum. The insulating polyethylene between the probe and sample ensures sterility of the field of operation, thus allowing multiple uses of the same probe.…”