Devices and methods for treatment of luminal tissue
Devices and methods are provided for treatment of tissue in a body lumen with an electrode deployment device. Embodiments typically include a device with a plurality of electrodes having a pre-selected electrode density arranged on the surface of a support. The support may comprise a non-distensible electrode backing that is spirally furled about an axis and coupled to an expansion member such as an inflatable elastic balloon. In some embodiments, the balloon is inflated to selectively expose a portion of the electrode surface while maintaining the electrode density.
1. A method for treating tissue in an esophagus, the method comprising:
inserting an electrode deployment apparatus into an esophagus, the electrode deployment apparatus comprising an array of electrodes arranged on an exterior surface of an expandable support in a pre-selected electrode density at a first expansion size;
radially expanding the expandable support to a second expansion size to engage electrodes with a wall of the esophagus while maintaining the electrode density of the engaged electrodes about the exterior surface of the support; and
delivering energy from the electrodes to the esophagus.
2. The method of claim 1 , wherein the expandable support is dimensionally stable.
3. The method of claim 1 , wherein the electrode deployment apparatus further comprises an expansion member coupled to the expandable support.
4. The method of claim 3 , wherein the expandable support is furled about an axis and wherein expanding the support radially comprises unfurling the support to selectively expose a portion of the array.
5. The method of claim 4 , wherein unfurling comprises expanding the expansion member.
6. The method of claim 5 , wherein expanding the expansion member comprises inflating a balloon.
7. The method of claim 6 , wherein expanding the expansion member comprises unfurling the support by applying force against a retaining elastic member adapted to retain the support from unfurling freely.
8. The method of claim 7 , further comprising removing the force against the elastic member after delivering energy to the esophagus.
9. The method of claim 3 , wherein the electrode deployment apparatus further comprises a movable shield associated with the expansion member, the expanding step comprising exposing at least a first portion of the array and shielding a second portion of the array.
10. The method of claim 1 , wherein the energy is radiofrequency energy applied through a multiplicity of bipolar electrode pairs in the array.
11. The method of claim 10 , wherein the electrodes are parallel, have a width in the range from 0.1 mm to 3 mm, and are spaced-apart by a distance in the range from 0.1 mm to 3 mm.
12. The method of claim 11 , wherein the radiofrequency energy is delivered at a total dosage in the range from 1 joules/cm 2 to 50 joules/cm 2 .
13. The method of claim 12 , wherein the radiofrequency energy is delivered over a time period below 5 seconds.