Surgical forceps including thermal spread control

Abstract

A surgical instrument includes one or more electrically-conductive plates adapted to connect to a source of energy for supplying energy to tissue to treat tissue, a temperature sensing element, and a thermal spread control assembly coupled to the temperature sensing element. The thermal spread control assembly is configured to determine a flow rate of heat energy across the temperature sensing element and to control the energy applied to the electrically-conductive plate and/or control active cooling of the temperature sensing element in accordance with the determined flow rate of heat energy.

1 - 20 . (canceled) 
     
     
         21 . A surgical instrument, comprising:
 an electrode defining a first side and a second side, the electrode adapted to connect to a source of energy for supplying energy to tissue to treat tissue;   at least one temperature sensor associated with the first electrode, the at least one temperature sensor configured to sense a first temperature adjacent the first side of the electrode and a second temperature adjacent the second side of the electrode; and   a controller coupled to the temperature sensor, the controller configured to determine a flow rate of heat energy across the first electrode based at least in part on the first temperature and the second temperature.   
     
     
         22 . The surgical instrument according to  claim 21 , wherein the controller is configured to control the energy applied to the electrode in accordance with the determined flow rate of heat energy. 
     
     
         23 . The surgical instrument according to  claim 22 , wherein the controller is configured configured to control the energy applied to the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy within a range. 
     
     
         24 . The surgical instrument according to  claim 22 , wherein the controller is configured configured to control the energy applied to the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy below a threshold. 
     
     
         25 . The surgical instrument according to  claim 21 , wherein the controller is configured to control active cooling of the electrode in accordance with the determined flow rate of heat energy. 
     
     
         26 . The surgical instrument according to  claim 25 , wherein the controller is configured configured to control the active cooling of the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy within a range. 
     
     
         27 . The surgical instrument according to  claim 25 , wherein the controller is configured configured to control the active cooling of the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy below a threshold. 
     
     
         28 . The surgical instrument according to  claim 25 , further comprising a thermoelectric cooler operably coupled to the electrode, wherein the thermoelectric cooler is configured to actively cool the electrode, and wherein the controller is configured to control the thermoelectric cooler. 
     
     
         29 . The surgical instrument according to  claim 21 , wherein the controller is configured to determine the flow rate of heat energy across the electrode in accordance with the first and second temperatures and a thermal conductivity of the electrode. 
     
     
         30 . A method of treating tissue, comprising:
 applying energy from an electrode to tissue, the electrode having a first side and a second side;   determining a first temperature adjacent the first side of the electrode;   determining a second temperature adjacent the second side of the electrode; and   determining a rate of flow of heat energy across the electrode based at least in part on the first temperature and the second temperature.   
     
     
         31 . The method according to  claim 30 , further comprising controlling a supply of energy to the electrode based upon the determined flow rate of heat energy. 
     
     
         32 . The method according to  claim 31 , further comprising controlling the supply of energy to the electrode based upon the determined flow rate of heat energy to maintain the flow rate of heat energy within a range. 
     
     
         33 . The method according to  claim 31 , further comprising controlling the supply of energy to the electrode based upon the determined flow rate of heat energy to maintain the flow rate of heat energy below a threshold. 
     
     
         34 . The method according to  claim 31 , further comprising controlling active cooling of the electrode in accordance with the determined flow rate of heat energy. 
     
     
         35 . The method according to  claim 34 , further comprising controlling the active cooling of the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy within a range. 
     
     
         36 . The method according to  claim 34 , further comprising controlling the active cooling of the electrode in accordance with the determined flow rate of heat energy to maintain the flow rate of heat energy below a threshold. 
     
     
         37 . The method according to  claim 31 , wherein the flow rate of heat energy across the electrode is determined in accordance with the first and second temperatures and a thermal conductivity of the electrode.