Ablation treatment apparatus

Abstract

An RF treatment apparatus includes a catheter with a catheter lumen. A removable needle electrode is positioned in the catheter lumen in a fixed relationship to the catheter. The needle electrode includes a needle lumen and a needle electrode distal end. A removable introducer is slidably positioned in the needle lumen. The introducer includes an introducer distal end. A first sensor is positioned on a surface of the needle electrode or the insulator. An RF power source is coupled to the needle electrode and a return electrode. An insulator sleeve is slidably positioned around the electrode and includes a second sensor. Resources are associated with the electrodes, sensors as well as the RF power source for maintaining a selected power at the electrode independent of changes in current or voltage.

1 - 32 . (canceled)  
     
     
         33 . A probe system comprising: 
 an introducer having a distal end and a proximal end;    at least one retractable electrode at least partly positioned in the introducer that is adapted to be inserted into tissue, is adapted to penetrate tissue, and is adapted to extend to a selected tissue site, said at least one retractable electrode having a non-deployed state when positioned in the introducer, being preformed to assume a curved shape when deployed, and being operatively connected to a microwave power source; and    wherein the at least one electrode is advanceable in and out of the distal most end of the introducer.    
     
     
         34 . The probe system of  claim 33 , wherein the introducer is operatively coupled to an RF or a microwave power source.  
     
     
         35 . The probe system of  claim 33 , further comprising: 
 at least one thermal sensor coupled to at least one of (i) the introducer, or (ii) at least one of the at least one electrode.    
     
     
         36 . The probe system of  claim 35 , further comprising: 
 a feedback control system operatively coupled to the at least one sensor and the RF or microwave power source.    
     
     
         37 . The probe system of  claim 36 , wherein the feedback control adjusts at least one of (i) a power level, (ii) a duty cycle, and (iii) an energy delivery in response to the temperature measured at the at least one sensor.  
     
     
         38 . The probe system of  claim 35 , further comprising: 
 a display for displaying temperature values measured at the at least one sensor.    
     
     
         39 . The probe system of  claim 33 , wherein said at least one electrode comprises at least two electrodes, each being operatively coupled to the RF or microwave power source, and each of the at least two electrodes having an energy delivery surface to create an ablation volume between the energy delivery surfaces.  
     
     
         40 . The probe system of  claim 33 , wherein each of the electrodes includes at least one thermal sensor.  
     
     
         41 . The probe system of  claim 33 , further comprising: 
 an insulation sleeve positioned in a surrounding relationship around at least a portion of the at least one electrode.    
     
     
         42 . The probe system of  claim 41 , wherein the insulation sleeve is adjustably moveable along an exterior of the at least one electrode.  
     
     
         43 . The probe system of  claim 33 , wherein at least one of the at least one electrodes is hollow and coupled to an infusion medium source to receive an infusion medium.  
     
     
         44 . The probe system of  claim 33 , wherein the distal end of the introducer has a tissue piercing distal end.  
     
     
         45 . A method for creating an ablation volume in a selected tissue mass, comprising: 
 providing an ablation device with an introducer having a lumen, at least one electrode with a distal end being operatively coupled to a microwave energy source, and at least one thermal sensor coupled to at least one of (i) the introducer, or (ii) at least one of the at least one electrodes;    inserting the introducer into the selected tissue mass with the at least one electrode distal end positioned in the introducer lumen;    advancing the at least one electrode distal end out of the introducer lumen and into the selected tissue mass, wherein the electrode has a preformed, curved shape;    delivering electromagnetic energy from the microwave energy source to the at least one electrode; and    creating an ablation volume in the selected tissue mass.    
     
     
         46 . The method of  claim 45 , wherein said at least one electrode comprises at least two electrodes, each having an energy delivery surface, are advanced from the introducer, and an ablation volume is created between the two electrodes energy delivery surfaces.  
     
     
         47 . The method of  claim 45 , further comprising: 
 measuring temperature with the at least one thermal sensor; and    adjusting energy delivered to the at least one electrode from the microwave energy source in response to the measured temperature.    
     
     
         48 . The method of  claim 45 , wherein the elongate member is operatively coupled to an energy source and has an energy delivery surface, further comprising 
 delivering energy to the introducer energy delivery surface.    
     
     
         49 . The method of  claim 48 , wherein said energy source is an RF energy source and said delivering energy comprises delivering RF energy.