Microwave ablation devices including expandable antennas and methods of use

Abstract

A microwave ablation device for treating tissue includes an inner conductor having a length and a distal end and configured to deliver energy, a wire extending adjacent the inner conductor and axially translatable relative thereto, the wire including a length and a distal end, a distal tip disposed in mechanical cooperation with the distal end of the inner conductor and the distal end of the wire, and an outer conductor including a distal end and defining a longitudinal axis, the outer conductor at least partially surrounding the inner conductor and the wire at least partially along their lengths. The distal tip is movable substantially along the longitudinal axis with respect to the outer conductor and relative movement of the distal tip towards the distal end of the outer conductor causes at least a portion of the inner conductor to move away from the longitudinal axis.

1 - 20 . (canceled) 
     
     
         21 . An electrosurgical device, comprising:
 a wire defining a longitudinal axis;   an outer conductor at least partially surrounding the wire;   a distal tip portion coupled to the wire, the wire configured to move the distal tip portion along the longitudinal axis; and   an inner conductor at least partially surrounded by the outer conductor and having an insulated portion and an uninsulated portion, the inner conductor configured to move away from the longitudinal axis upon movement of the distal tip portion along the longitudinal axis to form a bend at the uninsulated portion of the inner conductor for treating tissue.   
     
     
         22 . The electrosurgical device according to  claim 21 , wherein the uninsulated portion is surrounded by the insulated portion. 
     
     
         23 . The electrosurgical device according to  claim 21 , wherein the inner conductor is configured to be disposed orthogonal to the longitudinal axis upon movement of the distal tip portion along the longitudinal axis. 
     
     
         24 . The electrosurgical device according to  claim 21 , further comprising a plurality of inner conductors radially spaced from each other about the longitudinal axis. 
     
     
         25 . The electrosurgical device according to  claim 21 , wherein the electrosurgical device is a microwave antenna configured to deliver microwave energy to tissue. 
     
     
         26 . The electrosurgical device according to  claim 21 , further comprising a dielectric material disposed between the inner and outer conductors and surrounding at least a portion of the wire. 
     
     
         27 . The electrosurgical device according to  claim 21 , wherein the distal tip portion is electrically coupled to the wire. 
     
     
         28 . The electrosurgical device according to  claim 21 , wherein the distal tip portion includes a tapered distal tip configured to pierce tissue. 
     
     
         29 . The electrosurgical device according to  claim 21 , wherein the inner conductor is configured to pierce tissue. 
     
     
         30 . The electrosurgical device according to  claim 21 , wherein the distal tip portion is configured to move along the longitudinal axis toward a distal end of the outer conductor to move the inner conductor away from the longitudinal axis. 
     
     
         31 . The electrosurgical device according to  claim 21 , wherein the wire is configured to move along the longitudinal axis relative to the outer conductor. 
     
     
         32 . The electrosurgical device according to  claim 21 , wherein the distal tip portion is mechanically and electrically connected to a distal end of the inner conductor and a distal end of the wire. 
     
     
         33 . The electrosurgical device according to  claim 21 , wherein the bend divides the uninsulated portion to include a proximal-facing surface and an opposing distal-facing surface. 
     
     
         34 . The electrosurgical device according to  claim 21 , wherein the insulated portion includes a first insulated surface extending proximally from a first end of the uninsulated portion and a second insulated surface extending distally from a second end of the uninsulated portion to the distal tip portion. 
     
     
         35 . An electrosurgical device, comprising:
 a feedline defining a longitudinal axis, the feedline including:
 an inner conductor configured to treat tissue and having an insulated portion and an uninsulated portion; 
 an outer conductor at least partially surrounding the inner conductor; and 
 a dielectric material disposed between the inner and outer conductors; and 
   a distal tip portion connected to the inner conductor and configured to move along the longitudinal axis to move the inner conductor away from the longitudinal axis such that the inner conductor forms a bend at the uninsulated portion for treating tissue.   
     
     
         36 . The electrosurgical device according to  claim 35 , further comprising a wire extending along the longitudinal axis and having a distal end connected to the distal tip portion, the wire configured to move the distal tip portion along the longitudinal axis. 
     
     
         37 . The electrosurgical device according to  claim 35 , wherein the distal tip portion is mechanically and electrically connected to a distal end of the inner conductor. 
     
     
         38 . The electrosurgical device according to  claim 35 , wherein the bend divides the uninsulated portion to include a proximal-facing surface and an opposing distal-facing surface. 
     
     
         39 . The electrosurgical device according to  claim 35 , wherein the insulated portion includes a first insulated surface extending proximally from a first end of the uninsulated portion and a second insulated surface extending distally from a second end of the uninsulated portion to the distal tip portion. 
     
     
         40 . The electrosurgical device according to  claim 35 , wherein the uninsulated portion is surrounded by the insulated portion.