Query electrodes are provided for monitoring the electrical impedance of tissue as it is treated with electrosurgical energy. In one embodiment, based on a predicted model of tissue impedance and a number of initial impedance readings, the impedance at which tissue treatment is completed is...http://www.google.de/patents/US5817093?utm_source=gb-gplus-sharePatent US5817093 - Impedance feedback monitor with query electrode for electrosurgical instrument 
