Patent ID: 8764744
Filing Date: 2014-07-01
Classification: A61B

Abstract:
1. A system for monitoring ablation size, comprising: a power source having an electrical circuit that provides microwave energy; a microwave antenna including a radiating section configured to deliver the microwave energy from the power source to tissue to form an ablation zone; and a plurality of spaced-apart electrodes operably disposed along a length of the microwave antenna, the electrodes in electrical communication with one another, each of the electrodes having a threshold impedance associated therewith corresponding to the radius of the ablation zone, wherein the plurality of spaced-apart electrodes includes a series of proximal spaced-apart electrodes along the shaft and a distal electrode operably disposed at a distal tip of the shaft, and wherein a voltage potential is present between at least one of the series of proximal spaced-apart electrodes and the distal electrode as a result of delivery of microwave energy to the microwave antenna such that current flows between the at least one proximal electrode and the distal electrode and returns to the power source via a closed loop electrical circuit that is provided in the microwave antenna and separate from the electrical circuit that provides microwave energy to the radiating section of the microwave antenna.