#$%^&*AU2007202464B220120524.pdf#####SYSTEM AND METHOD FOR CONTROLLING TISSUE HEATING RATE PRIOR TO CELLULAR VAPORIZATION ABSTRACT A system and method for performing electrosurgical procedures are disclosed. The system includes an electrosurgical generator (20) adapted to supply energy at an output level to tissue and to transmit an interrogatory signal to obtain initial tissue impedance to derive a starting impedance value. The electrosurgical generator (20) includes a 5 microprocessor (25) adapted to generate a desired impedance trajectory as a function of either of the initial tissue impedance or the starting impedance value. The desired impedance trajectory includes a plurality of target impedance values. The electrosurgical generator (20) is further adapted to drive tissue impedance along the desired impedance trajectory by adjusting the output level to match tissue impedance to a corresponding target 10 impedance value. The system also includes an electrosurgical instrument (10) including at least one active electrode adapted to apply electrosurgical energy to tissue. 807728_1.DOC2/3 START 100 TRANSMIT INTERROGATORY SIGNAL TO OBTAIN INITIAL TISSUE IMPEDANCE ,110 SUPPLY ELECTROSURGICAL ENERGY TO TISSUE , 120 CONTINUOUSLY MONITOR TISSUE IMPEDANCE , 130 GENERATE DESIRED IMPEDANCE TRAJECTORY FROM STARTING IMPEDANCE TO MINIMUM IMPEDANCE , 140 DRIVE IMPEDANCE DOWN ALONG DESIRED IMPEDANCE TRAJECTORY r 150 OBTAIN MINIMUM IMPEDANCE 160 MONITOR TARGET ERROR TO DETERMINE IF ERROR IS ABOVE THRESHOLD , r 170 IDENTIFY WHETHER PHASE II H AS OCCURRED 180 CONTROL ENERGY SUPPLY TO COMPLETE PROCEDURE END FIG. 3
