Impedance-based method and apparatus for monitoring cryodestruction in controlled cryosurgery

摘要

An impedance-based method for the controlled cryosurgery of a patient's malignant tumor consisting of the steps: placing a contact electrode electrically connected to an impedance meter in electric contact with a body site spaced away from the tumor target, inserting a needle electrode electrically connected to the impedance meter through the tumor target with the tip of the needle electrode penetrating the immediately underlying normal tissue therebelow, and monitoring during cryosurgery the impedance between the two electrodes as a reflection of the eutectic state of the tissue circumadjacent the tip of the needle electrode.