Liner for cryogenic treatment systems

A liner configured for expansion within a uterine cavity, comprising:

• a flexible membrane which is configured to have a flattened shape when in an unexpanded configuration and a contoured shape which conforms to the uterine cavity when in an expanded configuration;
• an elongate shaft upon which a proximal portion of the membrane is attached;
• a sheath assembly that is slidably retractable relative to the flexible membrane and the elongate shaft such that a length of the expanded configuration is adjustable by retraction of the sheath;
• an elongate probe having a distal tip and a flexible length which is positionable through the second width and into the interior of the membrane;
• at least one infusion lumen positioned through or along the elongate probe, wherein the infusion lumen defines one or more openings along its length;
• at least one delivery lumen slidingly positioned through or along the infusion lumen, wherein translation of the delivery lumen relative to the infusion lumen controls a number of unobstructed openings along the infusion lumen;
• and
• a securement mechanism positioned along the sheath assembly and configured to hold a position of the sheath to maintain the length of the expanded configuration and simultaneously adjust a position of the at least one delivery lumen relative to the infusion lumen such that the number of unobstructed openings is maintained,
• wherein the membrane in the expanded configuration has a length which tapers from a first width to a second width which is smaller than the first width and which is sized to receive an instrument therethrough into an interior of the membrane,
• wherein the first width comprises a first curved portion and a second curved portion opposite to the first curved portion where the first and second curved portions each define a gentle radius such that the membrane between the first and second curved portions defines a first region having a first radius which extends proximally relative to the first and second curved portions,
• wherein the membrane proximal to the first and second curved portions further defines a second region having a second radius different from the first radius, and
• wherein the membrane proximal to the second region further defines a third region having a third radius which is opposite relative to the second radius.