Electrosurgical medical system and method

Abstract

A method for controlling an electrosurgical electrode of a medical device includes operating an RF generator to generate an RF signal at a first RF power level to initiate tissue cutting, the first RF power level being associated with a start mode of the RF generator; operating the RF generator to generate the RF signal at a second RF power level for tissue cutting, the second RF power level being lower than first RF power level, the second RF power level being associated with a cutting mode of the RF generator; monitoring an electrical characteristic associated with an electrosurgical electrode with a sensor; and adjusting a DC input voltage applied to an output stage of an RF amplifier based on the monitored electrical characteristic associated with the electrosurgical electrode to maintain a desired RF power output and a desired RF duty cycle at the second RF power level.

1 - 47 . (canceled) 
     
     
         48 . A method for controlling an electrosurgical electrode of a medical device, comprising:
 providing an RF generator coupled to an electrosurgical electrode and to a return electrode, the RF generator including an RF amplifier;   operating the RF generator to generate an RF signal at a first RF power level to initiate tissue cutting, the first RF power level being associated with a start mode of the RF generator;   operating the RF generator to generate the RF signal at a second RF power level for tissue cutting, the second RF power level being lower than first RF power level, the second RF power level being associated with a cutting mode of the RF generator;   monitoring an electrical characteristic associated with the electrosurgical electrode with a sensor; and   adjusting a DC input voltage applied to an output stage of the RF amplifier based on the monitored electrical characteristic associated with the electrosurgical electrode to maintain a desired RF power output and a desired RF duty cycle at the second RF power level.   
     
     
         49 . The method as in  claim 48 , comprising selecting one of a run RF duty cycle for a run mode and a start RF duty cycle for a start mode, the start mode preceding the run mode. 
     
     
         50 . The method as in  claim 48 , comprising maintaining a constant duty cycle and adjusting at least one of an RF output voltage and an RF output current of the second RF power level during the cutting mode during which the electrosurgical tissue cutting electrode is cutting. 
     
     
         51 . The method of  claim 48 , further comprising automatically switching from the start mode to the run mode when the electrosurgical tissue cutting electrode begins the tissue cutting and wherein the establishing the desired RF power output and the desired RF duty cycle takes place during both the start mode and the run mode and includes maintaining a lower RF power output in the run mode than in the start mode. 
     
     
         52 . The method as in  claim 51 , comprising maintaining a different duty cycle in the run mode than in the start mode. 
     
     
         53 . The method as in  claim 51 , wherein the switching occurs responsive to an onset of plasma generation at the electrosurgical tissue cutting electrode. 
     
     
         54 . A method for controlling an electrosurgical electrode of a medical device, comprising:
 providing a hand-held electrosurgical electrode having a cutting probe, the cutting probe having a free distal end;   providing a return electrode configured to be positioned remote from the electrosurgical electrode;   providing an RF generator coupled to the electrosurgical electrode and to the return electrode, the RF generator including an RF amplifier;   operating the RF generator to generate an RF signal at a first RF power level to initiate tissue cutting, the first RF power level being associated with a start mode of the RF generator;   operating the RF generator to generate the RF signal at a second RF power level for tissue cutting, the second RF power level being lower than first RF power level, the second RF power level being associated with a cutting mode of the RF generator;   monitoring an electrical characteristic associated with the electrosurgical electrode with a sensor; and   adjusting a DC input voltage applied to an output stage of the RF amplifier based on the monitored electrical characteristic associated with the electrosurgical electrode to maintain a desired RF power output and a desired RF duty cycle at the second RF power level.   
     
     
         55 . The method as in  claim 54 , comprising selecting one of a run RF duty cycle for a run mode and a start RF duty cycle for a start mode, the start mode preceding the run mode. 
     
     
         56 . The method as in  claim 54 , comprising maintaining a constant duty cycle and adjusting at least one of an RF output voltage and an RF output current of the second RF power level during the cutting mode during which the electrosurgical tissue cutting electrode is cutting. 
     
     
         57 . The method of  claim 54 , further comprising automatically switching from the start mode to the run mode when the electrosurgical tissue cutting electrode begins the tissue cutting and wherein the establishing the desired RF power output and the desired RF duty cycle takes place during both the start mode and the run mode and includes maintaining a lower RF power output in the run mode than in the start mode. 
     
     
         58 . The method as in  claim 57 , comprising maintaining a different duty cycle in the run mode than in the start mode. 
     
     
         59 . The method as in  claim 57 , wherein the switching occurs responsive to an onset of plasma generation at the electrosurgical tissue cutting electrode.