System and method for performing ablation using an expandable member

1. An apparatus, comprising

a catheter defining a first lumen and a second lumen;

a conductive element disposed along the catheter;

a first expandable member having an interior in fluid communication with the first lumen of the catheter; and

a second expandable member having an interior in fluid communication with the second lumen of the catheter;

each of the first expandable member and second expandable member having respective conductive portions and non-conductive portions, the first expandable member comprising an inner balloon, and the second expandable member comprising an outer balloon, the inner and outer balloons being arranged such that the conductive portions of the inner balloon are aligned with the non-conductive portions of the outer balloon, and the non-conductive portions of the inner balloon are aligned with the conductive portions of the outer balloon.

2. The apparatus of claim 1 , further comprising: an insulation layer disposed between the first expandable member and the second expandable member.

3. The apparatus of claim 1 , the apparatus comprising a bi-polar tissue ablation device, wherein one or more conductive portions of the second expandable member are coupled to a first pole of the device, and one or more conductive portions of the first expandable member are coupled to a second pole of the device.

4. The apparatus of claim 1 , wherein the second expandable member in the expanded configuration has a size associated with a previously-formed tissue cavity.

5. The apparatus of claim 1 , wherein the first expandable member and the second expandable member are disposed concentrically.

6. A method, comprising:

percutaneously disposing at least a portion of a catheter while in a collapsed configuration into a tissue cavity previously-formed by removal of a tissue mass, the portion of the catheter including a first expandable member disposed within a second expandable member, at least a portion of the first expandable member or the second expandable member being formed of a conductive material to define a conductive portion;

expanding each of the first expandable member and the second expandable member into an expanded configuration, the second expandable member in the expanded configuration having a shape associated with a shape of the previously-formed tissue cavity; and

applying a radio-frequency signal to the conductive portion of the first expandable member or the second expandable member.

7. The method of claim 6 , wherein the expanding includes disposing a fluid within the first expandable member having a temperature less than a temperature of the conductive portion of the first expandable member.

8. The method of claim 6 , wherein the second expandable member is fluid permeable, the expanding includes disposing a fluid into the second expandable member such that at least a portion of the fluid is perfused through the second expandable member and into the tissue cavity.

9. The method of claim 6 , wherein the second expandable member is fluid permeable, the method further comprising:

measuring an impedance associated with the tissue cavity,

the expanding includes providing a fluid within the second expandable member based on the impedance associated with the tissue cavity.

10. The method of claim 6 , the applying including modifying the shape of the previously-formed tissue cavity to produce a modified tissue cavity having a substantially spherical shape, the method further comprising:

removing the portion of the catheter from the modified tissue cavity;

inserting a radiation therapy device into the modified tissue cavity; and

performing radiation therapy based on the radiation therapy device.

11. The method of claim 6 , wherein the applying includes applying the radio-frequency signal to the conductive portion of the first expandable member or the second expandable member such that heat from the conductive portion of the first expandable member or the second expandable member ablates at least a portion of a margin tissue associated with the tissue cavity.

12. A bi-polar tissue ablation device, comprising:

a catheter defining a lumen; and

an expandable member coupled to a distal end of the catheter, and having an interior in fluid communication with the lumen of the catheter, the expandable member comprising a first conductive layer, an insulation layer, and a second conductive layer, the second conductive layer and the insulation layer each having distinct segments in which one segment of the insulation layer is disposed between the first conductive layer and an associated segment of the second conductive layer, the first conductive layer including portions upon which the respective insulation layer and second conductive layer are not disposed.

13. The bi-polar device of claim 12 , wherein the first conductive layer acts as one pole, and second conductive layer acts as another pole.