Patent ID: 6409722
Filing Date: 2002-06-25
Classification: A61B

Abstract:
An apparatus for producing, maintaining, and controlling a virtual electrode for a provision of RF current therapy through the virtual electrode to a target tissue of a body of a patient, the apparatus providing a conductive fluid and an RF current via at least one surgical instrument to the target tissue to create the virtual electrode, the apparatus comprises:a generator of RF current, the generator supplying the RF current to the virtual electrode via the surgical instrument; means for detecting an electrical arc; means for measuring the impedance of the body of the patient to the passage of the RF current; at least one primary temperature sensor for sensing the temperature at least a first predetermined location in the body of the patient; at least one source of conductive fluid selectively providing conductive fluid to the target tissue; and means for controlling a rate of application of the conductive fluid to the target tissue and for controlling a power level of the RF current, the means for controlling receiving arc detection signals from the arc detection means, impedance measurement signals from the impedance measuring means, and temperature measurement signals from the at least one temperature sensor, the power level of the RF current and the rate of conductive fluid flow controlled by the controlling means in response to changes in the measured impedance and the sensed temperature, the means for controlling discontinuing the application of RF current for a predetermined period of time upon receiving signals indicating a detection of an electrical arc.