A experimental study of the microwave tissue coagulation therapy using a new type needle-electrode

Abstract

In order to extend the possible use of the microwave tissue coagulation (MTC) in the liver tumor, macroscopic and histological changes in thigh muscle of the pig after microwave irradiation using a new type needle electrode of that size was 21 gauge was examined in this study. The needle-electrode of MTC was introduced into the center of the muscle under the guide of the ultra sonography and MTC was performed at the out put of 20 watts for 30 seconds at a time, The maximum coagulation area of the MTC in the fresh cut surface of the muscle was 20mm×10mm in size when it was irradiated continuously ten times, and was oval shaped. The coagulation area was changed necrosis strongly stained with hematoxylin. Internal echo pattern of the coagulation area of the MTC was changed heterogeneously surrounded with low echoic region. Thus, the result suggests that this new type needle-electrode is effective in the small liver tumor at the bed side treatment.