Devices and methods for treatment of luminal tissue

1. An electrode deployment apparatus for treatment of tissue in a body lumen, the apparatus comprising:

an expansion member having a surface; and

a dimensionally-stable support having a first end, a second end and a surface;

a plurality of electrodes arranged on the surface of the support;

the support and the expansion member coupled together at attachment sites near the first end and the second end of the support, the support furled around the expansion member in a non-overlapping configuration to provide a circumferential portion of the expansion member covered by the support.

2. The apparatus of claim 1 comprising a circumferential gap on the surface of the expansion member between the attachment sites, the gap not being covered by the support.

3. The apparatus of claim 2 configured such that, upon expansion of the expansion member, the circumferential portion covered by the support remains dimensionally constant and the circumferential gap expands.

4. The apparatus of claim 1 configured such that upon expansion of the expansion member, the plurality of electrodes on the surface of the support remains at a constant surface area density.

5. The apparatus of claim 1 further comprising one or more attachment sites coupling the support and the expansion member together at a site other than the attachment sites near the first end and the second end of the support.

6. The apparatus of claim 5 wherein one of the one or more attachment sites is positioned circumferentially midway between the first end and the second end of the support.

7. The apparatus of claim 1 wherein the plurality of electrodes form a treatment area that is less than completely circumferential.

8. The apparatus as in claim 1 , further comprising wiring adapted to connect the electrodes to a radiofrequency power source as a multiplicity of bipolar pairs.

9. The apparatus as in claim 1 , wherein the support comprises a non-distensible, electrode backing.

10. The apparatus as in claim 9 , wherein at least a portion of the electrode backing is spirally furled about an axis of an expansion member prior to deployment while maintaining a non-overlapping configuration in relation to an exterior portion of the expansion member.

11. The apparatus as in claim 9 , wherein the electrodes are aligned in a generally axial direction on the surface of the electrode backing.

12. The apparatus as in claim 9 , wherein the electrodes are aligned in a generally transverse direction on the surface of the electrode backing.

13. The apparatus as in claim 1 , wherein the electrodes are linear and arranged in a parallel pattern on the support.

14. The apparatus as in claim 1 , wherein the electrodes are non-linear and arranged in a parallel pattern on the support.

15. The apparatus as in claim 1 , wherein the electrodes have a width in the range from 0.1 mm to 3 mm and a spacing in the range from 0.1 mm to 3 mm.

16. The apparatus as in claim 1 , wherein the expansion member comprises a balloon.

17. An electrode deployment apparatus for treatment of tissue in an esophagus, the apparatus comprising:

an expansion member having a circumference;

a dimensionally-stable electrode support having a first end and a second end; the first end of the support attached to the expansion member, the support furled around the circumference of the expansion member, the second end terminating non-overlappingly near the first end; and

an electrode array on the support.

18. The apparatus as in claim 17 , wherein the second end of the support is attached to the expansion member.

19. The apparatus as in claim 17 , wherein as the expansion member expands, a gap forms between the first end of the support and the second end of the support.

20. The apparatus as in claim 19 , wherein as the expansion member expands, a gap increases.

21. The apparatus as in claim 19 , wherein as the expansion member expands, the surface area of the electrode array remains constant.

22. The apparatus of claim 19 wherein the gap between the first end and the second end corresponds to a portion of the circumference of the esophagus that is void of treatment.

23. The apparatus of claim 17 further comprising one or more attachment sites coupling the electrode support and the expansion member together at a midpoint between the first end and second end of the support.

24. The apparatus of claim 17 wherein the surface area of the electrode array corresponds to a treatment area of the esophagus.

25. The apparatus of claim 17 wherein the gap between the first end of the support and the second end of the support is a portion of the circumference of the expansion member that is void of a treatment surface.

26. An electrode deployment apparatus for treatment of tissue in an esophagus, the apparatus comprising:

an expansion member having a circumference;

an electrode support comprising a flexible, non-distensible backing, a first end, and a second end; the support furled around the circumference of the expansion member, the first end and the second end terminating non-overlappingly on the expansion member, wherein upon expansion of the expansion member, a gap forms between the first end and the second end; and

an electrode array on the support.

27. The apparatus as in claim 26 , wherein as the expansion member expands, the gap increases.

28. The apparatus of claim 26 wherein as the expansion member expands, the gap expands to match an inside diameter of a treatment region of the esophagus.

29. The apparatus as in claim 26 , wherein as the expansion member expands, a surface area of the electrode array remains constant.

30. The apparatus of claim 26 wherein a surface area of the electrode array corresponds to a treatment area in the esophagus.

31. The apparatus of claim 26 wherein the gap between the first and second ends corresponds to a portion of the circumference of the esophagus that is void of treatment.