An apparatus for providing treatment to a target treatment area comprising: an operative member, wherein the operative member comprises a flexible circuit; and an expandable support device configured for delivery through a working channel and to the target treatment area, the expandable support device comprising an expandable support member configured for supporting the operative member, wherein the expandable support member comprises a plurality of splines (1630,1610) having a width and a spacing selected to promote expansion of the expandable support member between a collapsed configuration and an expanded configuration; wherein the plurality of splines comprises: a central axis spline; a first subset of splines extending away from the central axis spline in a first direction; and a second subset of splines extending away from the central axis spline in a different direction than the first direction, wherein each of said first subset of splines and second subset of splines comprises a plurality of splines, and wherein the first subset of splines and the second subset of splines extend away from the central axis spline at an angle such that the first subset of splines and second subset of splines extend from the central axis spline towards a distal end of the central axis spline; and wherein, when the support member is in the expanded configuration, a portion of the expandable support device defines a flat outwardly facing support surface, the operative member being disposed on said flat outwardly facing support surface and capable of bending with the expandable support device on which it is disposed, characterised in that the flexible circuit comprises a plurality of electrodes patterned to mirror the pattern of the plurality of splines. an operative member, wherein the operative member comprises a flexible circuit; and an expandable support device configured for delivery through a working channel and to the target treatment area, the expandable support device comprising an expandable support member configured for supporting the operative member, wherein the expandable support member comprises a plurality of splines (1630,1610) having a width and a spacing selected to promote expansion of the expandable support member between a collapsed configuration and an expanded configuration; wherein the plurality of splines comprises: a central axis spline; a first subset of splines extending away from the central axis spline in a first direction; and a second subset of splines extending away from the central axis spline in a different direction than the first direction, a central axis spline; a first subset of splines extending away from the central axis spline in a first direction; and a second subset of splines extending away from the central axis spline in a different direction than the first direction, wherein each of said first subset of splines and second subset of splines comprises a plurality of splines, and wherein the first subset of splines and the second subset of splines extend away from the central axis spline at an angle such that the first subset of splines and second subset of splines extend from the central axis spline towards a distal end of the central axis spline; and wherein, when the support member is in the expanded configuration, a portion of the expandable support device defines a flat outwardly facing support surface, the operative member being disposed on said flat outwardly facing support surface and capable of bending with the expandable support device on which it is disposed,