Multiple electrode ablation apparatus

A tissue ablation apparatus, comprising:

• a delivery catheter with a distal end and a proximal end;
• a handle attached to the proximal end of the delivery catheter;
• an electrode deployment device positioned at least partially in the delivery catheter and including a plurality of retractable electrodes that are inserted into tissue, penetrate tissue and surround a selected mass, each electrode having a non-deployed state when positioned within the delivery catheter, and a distended deployed state when advanced from the distal end of the delivery catheter defining an ablation volume between the deployed electrodes, each deployed electrode having at least one radii of curvature in two or more planes when advanced through the distal end of the delivery catheter and positioned at a desired tissue site;
• and
• an electrode advancement and retraction, member connected to the electrode deployment device, for advancing the electrodes in and out of the delivery catheter distal end.

A tissue ablation apparatus, comprising:

• a delivery catheter with a distal end and a proximal end;
• a handle attached to the proximal end of the delivery catheter;
• an electrode deployment device positioned at least partially in the delivery catheter and including a plurality of retractable electrodes that are inserted into tissue, penetrate tissue and surround a selected mass each electrode having a non-deployed state when positioned within the delivery catheter, and a distended deployed state when advanced from the distal end of the delivery catheter defining an ablation volume between the deployed electrodes, at least one deployed electrode having at least two radii of curvature, and at least one deployed electrode having at least one radius of curvature in two or more planes;
• and
• an electrode advancement and retraction member connected to the electrode deployment device, for advancing the electrodes in and out of the delivery catheter distal end.

A tissue ablation apparatus, comprising:

• a delivery catheter with a distal end and a proximal end;
• a handle attached to the proximal end of the delivery catheter;
• an electrode deployment device positioned at least partially in the delivery catheter including a plurality of retractable electrodes that are inserted into tissue, penetrate tissue and surround a selected mass, each electrode having a non-deployed state when positioned within the delivery catheter, and a distended deployed state when advanced out of the delivery catheter distal end defining an ablation volume between the deployed electrodes, at least one deployed electrode having at least one curved section located near the distal end of the delivery catheter, and a non-curved section extending beyond the curved section of the deployed electrode, and at least one deployed electrode having at least two radii of curvature;
• and
• an electrode advancement and retraction member connected to the electrode deployment device, for advancing the electrodes in and out of the delivery catheter distal end.

A tissue ablation apparatus, comprising:

• a delivery catheter with a distal end and a proximal end;
• a handle attached to the proximal end of the delivery catheter;
• an electrode deployment device positioned at least partially in the delivery catheter including a plurality of retractable electrodes that are inserted into tissue, penetrate tissue and surround a selected mass, each electrode having a non-deployed state when positioned within the delivery catheter, and a distended deployed state when advanced out of the delivery catheter distal end defining an oblation volume between the deployed electrodes, each deployed electrode having a first section with a first radius of curvature, the first section being located near the distal end of the delivery catheter, and a second section extending beyond the first section, the second section having one of a second radius of curvature, or a substantially linear geometry;
• and
• an electrode advancement and retraction member connected to the electrode deployment device, for advancing the electrodes in and out of the delivery catheter.

A tissue oblation apparatus, comprising:

• a delivery catheter with a distal end and a proximal end;
• a handle attached to the proximal end of the delivery catheter;
• an electrode deployment device positioned at least partially in the delivery catheter and including a plurality of retractable electrodes that are inserted into tissue, penetrate tissue and surround a selected mass, each electrode having a non-deployed state when positioned within the delivery catheter, and a distended deployed state when advanced from the delivery catheter defining an ablation volume between the deployed electrodes, each deployed electrode having at least one radii of curvature;
• and
• an electrode advancement and retraction member connected to the electrode deployment device, for advancing the electrodes in and out of the delivery catheter distal end.