Electrical ablation devices

Abstract

An electrical ablation apparatus comprises first and second electrodes. Each electrode comprises a first end configured to couple an energy source and a second end configured to couple to a tissue treatment region. An energy source is coupled to the first and second electrodes. At least one electrode is movable between a first position and a second position. A first necrotic zone having a first shape is created when the electrodes are energized in the first position and a second necrotic zone having a second shape is created when the electrodes are energized in the second position. At least one electrode may be pre-formed with a radius.

1 . An electrical ablation apparatus, comprising:
 first and second electrodes, each electrode comprising a first end configured to couple to an energy source and a second end configured to couple to a tissue treatment region;   wherein the first electrode is movable between a first position and a second position with respect to the second electrode;   wherein the first and second electrodes are configured to induce a zone of cell necrosis in a first shape when the first electrode is in the first position; and   wherein the first and second electrodes are configured to induce a zone of necrosis in a second shape when the first electrode is in the second position.   
     
     
         2 . The electrical ablation apparatus of  claim 1 , further comprising:
 a third electrode;   a first lumen configured to receive the first electrode;   a second lumen configured to receive the second electrode; and   a third lumen configured to receive the third electrode.   
     
     
         3 . The electrical ablation apparatus of  claim 2 , wherein the first electrode is pre-formed with a radius and rotatable within the first lumen and the third electrode is pre-formed with a radius and rotatable with the third lumen. 
     
     
         4 . The electrical ablation apparatus of  claim 2 , wherein the first, second, and third lumens each have a distal end comprising a cutting edge. 
     
     
         5 . The electrical ablation apparatus of  claim 1 , further comprising:
 an elongate sheath; and   a sleeve at least partially surrounding the elongate sheath, wherein the sleeve comprises the second electrode.   
     
     
         6 . The electrical ablation apparatus of  claim 5 , wherein the first electrode is deployable from a distal end of the elongate sheath and pre-formed with a radius. 
     
     
         7 . The electrical ablation apparatus of  claim 6 , wherein the first electrode is rotatable within the elongate sheath. 
     
     
         8 . The electrical ablation apparatus of  claim 1 , further comprising:
 a first elongate sheath;   a second elongate sheath; and   third and fourth electrodes, each electrode comprising a first end configured to couple to the energy source and a second end configured to couple to the tissue treatment region;   wherein the first and second electrodes are deployable from the first elongate sheath and the third and fourth electrodes are deployable from the second elongate sheath.   
     
     
         9 . The electrical ablation apparatus of  claim 8 , wherein the first and third electrodes each are pre-formed with a radius. 
     
     
         10 . The electrical ablation apparatus of  claim 8 , wherein the first elongate sheath and the second elongate sheath are substantially parallel. 
     
     
         11 . The electrical ablation apparatus of  claim 1 , further comprising:
 a fluid nozzle configured to deploy a fluid to bore a path in the tissue treatment region using a fluid, wherein the first electrode is configured to couple to the fluid in the path.   
     
     
         12 . The electrical ablation apparatus of  claim 11 , wherein the fluid nozzle is movable. 
     
     
         13 . The electrical ablation apparatus of  claim 11 , further comprising a plurality of fluid nozzles. 
     
     
         14 . The electrical ablation apparatus of  claim 1 , further comprising:
 an elongate shaft, wherein the first electrode is slidably engaged with the elongate sheath.   
     
     
         15 . The electrical ablation apparatus of  claim 14 , wherein the second electrode comprises a distal electrode and a proximal electrode each disposed along the elongate shaft. 
     
     
         16 . The electrical ablation apparatus of  claim 15 , wherein the first electrode is disposed on the elongate shaft intermediate the distal electrode and the proximal electrode. 
     
     
         17 . The electrical ablation apparatus of  claim 16 , further comprising:
 a first insulator disposed on the elongate shaft intermediate the distal electrode and the first electrode; and   a second insulator disposed on the elongate shaft intermediate the first electrode and the proximal electrode.   
     
     
         18 . An electrical ablation system, comprising:
 first and second electrodes, each electrode comprising a first end configured to couple to an energy source and a second end configured to couple to a tissue treatment region, wherein the first electrode is movable between a first position and a second position with respect to the second electrode, wherein the first and second electrodes are configured to induce a zone of cell necrosis in a first shape when the first electrode is in the first position, and wherein the first and second electrodes are configured to induce a zone of necrosis in a second shape when the first electrode is in the second position;   a first lumen configured to receive the first electrode;   a second lumen configured to receive the second electrode;   an alignment guide defining a passageway, wherein the passageway is configured to receive the first and second lumens; and   a handle coupled to the first and second lumens, wherein the handle is configured to rotatably move the first electrode from the first position to the second position.   
     
     
         19 . The electrical ablation system of  claim 18 , wherein the alignment guide comprises a plurality of position indicators positioned proximate to the passageway. 
     
     
         20 . An electrical ablation apparatus, comprising:
 first and second electrodes, each electrode comprising a first end configured to couple to an energy source and a second end configured to couple to a tissue treatment region;   wherein the first electrode is movable between a first position and a second position with respect to the second electrode;   wherein the first and second electrodes are configured to induce a zone of cell necrosis in a first shape when the first electrode is in the first position;   wherein the first and second electrodes are configured to induce a zone of necrosis in a second shape when the first electrode is in the second position; and   wherein a distance between the first and second electrodes is adjustable by rotating at least one of the first and second electrodes about a central axis of the at least one of the first and second electrodes.