System and method for performing plate type radiofrequency ablation

Abstract

A method and apparatus for inducing large volume heat ablations of tissue in a patient involving electrodes that are in contact with the patient's external surface or the surface of an internal organ. A high frequency signal or output from a generator is applied to the tissue near the area electrodes by connection of the generator to the electrodes. Various applications and configurations of electrodes and temperature monitoring are appropriate for different clinical needs and thermal distributions. The use for interoperative ablation of a tumor site within an internal organ or for ablation of a tumor from electrodes placed on the surface of the patient provides a clinical advantage.

What is claimed is:  
     
         1 . A system for inducing heat ablations in an operative field in a patient's anatomy, which includes tissue to be ablated, comprising: 
 at least one area electrode having an area greater than one square centimeter adapted to contact a portion of tissue proximate to a tissue volume within the operative field to be ablated;    a high frequency generator that generates an electrical output which when connected to the one area electrode applies heat to the tissue volume and induces an ablation proximate the one area electrode; and    an electrical coupling connecting the high frequency generator to the one area electrode.    
     
     
         2 . The system of  claim 1  wherein the at least one area electrode comprises one or more plates of conductive material.  
     
     
         3 . The system of  claim 1  wherein the at least one area electrode comprises a surface of conductive metal.  
     
     
         4 . The system of  claim 1  wherein the at least one area electrode comprises a conductive mesh of metal wires.  
     
     
         5 . The system of  claim 1  wherein the at least one area electrode comprises an area of a plurality of conductive elements.  
     
     
         6 . The system of  claim 1  wherein the at least one area electrode has a configuration suitable to conform the area electrode to the portion of tissue.  
     
     
         7 . The system of  claim 1  wherein the at least one area electrode comprises a temperature sensor to sense the temperature of the portion of tissue contacted.  
     
     
         8 . The system of  claim 1  and further comprising: 
 an imaging scanner to provide image representations of the tissue within the operative field so as to monitor the position of the at least one area electrode relative to the operative field.  
 
     
     
         9 . The system of  claim 1 , further comprising: 
 a structure for grasping two area electrodes to guide the area electrodes in positions relative to the portion of tissue within the operative field such that the two area electrodes grasp the portion of tissue between them.    
     
     
         10 . The system of  claim 1 , wherein the at least one area electrode comprises a fluid cooling system that cools at least a portion of the electrode to prevent excessive heating of the portion of tissue within the operative field.  
     
     
         11 . The system of  claim 1 , wherein the at least one area electrode comprises a plurality of electrodes, which are configured to enable insertion into the portion of tissue within the operative field.  
     
     
         12 . A system for heat coagulation of tissue within an operative field of a patient, comprising: 
 at least two area electrodes adapted to contact surface tissue within a portion of the body of the patient and each of the area electrodes having an area of at least one square centimeter, the two area electrodes for use within the operative field near to the tissue to be coagulated;    a high frequency generator that generates an electrical output, which when the at least two area electrodes are in contact with the surface tissue within the operative field and when the electrical output is connected to the at least two area electrodes, causes heating and coagulation of the tissue to be coagulated within the operative field; and    an electrical coupling of the generator to the at least two area electrodes.    
     
     
         13 . The system of  claim 12 , wherein the area electrodes comprise one or more plates of conductive material.  
     
     
         14 . The system of  claim 12  wherein the area electrodes comprise a surface of conductive metal.  
     
     
         15 . The system of  claim 12  wherein the area electrodes comprise a conductive mesh of metal wires.  
     
     
         16 . The system of  claim 12  wherein the area electrodes comprise an area of a plurality of conductive elements.  
     
     
         17 . The system of  claim 12  wherein the area electrodes conform to the surface tissue within the operative field.  
     
     
         18 . The system of  claim 12  wherein the area electrodes comprise a temperature sensor to sense the temperature of the surface tissue.  
     
     
         19 . The system of  claim 12 , further comprising: 
 a structure for grasping the area electrodes that enable the surface tissue within the operative field to be grasped by the area electrodes during the heat coagulation.    
     
     
         20 . The system of  claim 12  wherein the area electrodes comprise a fluid cooling system that cools at least a portion of the area electrodes.  
     
     
         21 . A method of heat ablation of tissue of a patient in an operative field, comprising the steps of: 
 disposing at least two area electrodes having area greater than one square centimeters in contact with the tissue within the operative field near to the tissue to be ablated within the operative field;    coupling the at least two area electrodes to a high frequency generator; and    applying electrical output from the generator to the tissue to be ablated within the operative field through the electrodes whereby to heat and ablate the tissue to be ablated within the operative field.    
     
     
         22 . The process of  claim 21 , further including the step of: 
 urging the area electrodes against tissue within the operative field with a grasping structure which is adapted to force the electrodes together and against the tissue within the operative field.    
     
     
         23 . The process of  claim 21 , wherein the grasping structure is a forceps with the electrodes coupled to the tongs of the forceps, and wherein the urging step comprises the step of applying a force on the forceps to close the electrodes together to press the electrodes against the tissue within the operative field.  
     
     
         24 . The process of  claim 21  wherein the area electrodes comprise temperature sensors to monitor the temperature of the tissue within the operative field near the electrodes, and further comprising the step of: 
 monitoring the temperature of the tissue within the operative field by the temperature sensors to control the heat ablation.