Nanosecond pulsing to treat a body lumen

An apparatus for delivering energy to a tissue, the system comprising:

• an elongate applicator tool comprising:
• an elongate shaft;
• a distal tip region at a distal end of the elongate shaft;
• a plurality of electrodes arranged along an outward-facing surface of the distal tip region;
• one or more contact projections extending from either side of the plurality of electrodes and configured to be moved away from the plurality of electrodes to remove or reduce wrinkles from the tissue;
• and
• a suction port configured to apply suction to draw the tissue against the plurality of electrodes.

A method comprising:

• placing a distal end region of an applicator tool against a wall of a body lumen, wherein the applicator tool comprises an electrode assembly at the distal end region having one or more electrodes;
• moving one or more contact projections from either side of the plurality of electrodes away from the plurality of electrodes and against the wall to remove or reduce wrinkles from the wall of the body lumen;
• applying suction to secure the one or more electrodes to the wall of the body lumen;
• and
• applying energy from the one or more electrodes to treat the wall of the body lumen.

An elongate applicator apparatus, the apparatus comprising:

• an elongate shaft;
• an actuating shaft extending within or adjacent to the elongate shaft;
• a distal tip region at a distal end of the elongate shaft comprising:
• one or more overlap band electrodes, each comprising a strip of conductive material wrapped over itself and configured to slide over itself to radially expand to a loop having a diameter that is greater than an outer diameter of the distal tip region as the actuating shaft is rotated.

A method, the method comprising:

• inserting a distal end of an elongate applicator into a body lumen, wherein the elongate applicator comprises an overlap band electrode at a distal tip region;
• rotating an actuating shaft of the elongate applicator to cause the overlap band electrode to slide over itself to radially expand to form a loop having a diameter that is greater than an outer diameter of the distal tip region;
• and
• applying an electrical treatment to a target region on or through the body lumen.