Abstract: A catheter adapted to increase the patency of a body conduit includes an elongate tube having an axis extending between a proximal end and a distal end, and a balloon disposed at the distal end of the tube and having properties for being expanded to a high-profile state and for being contracted to a low-profile state. A sleeve disposed over the balloon has a pair of ends disposed on opposing sides of a central section, the ends having a floating relationship relative to the tube with the central section disposed circumferentially of the balloon. An electrode disposed outwardly of the sleeve has properties for being electrosurgically energized to incise materials defining the body conduit when the balloon is in the high-profile state. The electrode can be formed of a plurality of elements stranded to increase the surface area of the electrode.

Abstract: An access device has a distal, expandable member with a low-profile state facilitating insertion and a high-profile state facilitating operation of the device. An obturator can be used to move the expandable member between its two states. Alternatively, the device can have an outer tube and an inner tube connected to respective ends of a cylindrical expansion member, so that co-axial movement of the tubes changes the state of the member. An actuator slideable on a handle facilitates the co-axial movement of the tubes, and a resulting formation of the expandable member in a funnel configuration.