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. An electrode deployment apparatus for treatment of tissue in a body lumen, the apparatus comprising:
a plurality of electrodes arranged on a surface of a dimensionally stable support at a pre-selected electrode density; and
an expansion member coupled to the support, wherein the support is furled at least partially around the expansion member in an overlapping manner such that the support unfurls as the expansion member expands to deploy and selectively expose a portion of the electrode surface while shielding a remaining portion and maintaining the electrode density.
2. The electrode deployment apparatus of claim 1 , wherein the expansion member is coupled with the support at a midpoint of the support, and first and second ends of the support are unattached and furled in opposite directions around the expansion member.
3. The electrode deployment apparatus of claim 1 , wherein the expansion member comprises a spring.
4. The electrode deployment apparatus of claim 3 , wherein the spring comprises a spring material comprising at least 316 stainless steel or nitinol.
5. The electrode deployment apparatus of claim 3 , wherein the support is attached to an outside surface of the spring.
6. The electrode deployment apparatus of claim 1 , wherein the expansion member comprises a balloon.
7. The electrode deployment apparatus of claim 1 , wherein the expansion member comprises one of a compliant balloon, a balloon with a tapered geometry, a basket, a plurality of struts, a foam, a bladder, or a backing material configured to expand to an expanded configuration when unrestrained.
8. The electrode deployment apparatus of claim 1 , further comprising:
a spring coupled with the support, wherein the spring is configured to provide at least a retraction or a constant force with respect to the support.
9. The electrode deployment apparatus of claim 1 , wherein the expansion member is coupled with the support at a first end of the support and a second end of the support is unattached and furled around the expansion member to overlap the first end.
10. The electrode deployment apparatus of claim 2 , further comprising a second support that is attached at its midpoint to a point on the expansion member approximately opposite the midpoint of the first support, the two ends of the second support overlapping the ends of the first support as they are furled around the expansion member.