Liner for cryogenic treatment systems
Liners for cryogenic treatment systems are described where a cryogenic fluid or gas may be introduced into a liner expanded within a body lumen such as the uterine cavity. The liner may be intentionally sized to be substantially larger than the typical size of the uterine cavity, e.g., 1.2 times (or more), greater than the size of the uterine cavity into which the liner is inserted. Because the liner is sized intentionally larger than the body lumen to be treated, the liner may never fully expand when deployed. But even with folds or portions of the liner being folded upon itself, the liner may remain sufficiently supple such that the resulting uncontrolled folds allow for complete conformance of the liner against the anatomy of the contacted tissue.
1. A method of treating tissue, comprising:
positioning an elongate probe into a body lumen to be treated;
expanding a liner enclosing the probe from a delivery configuration to an expanded configuration which is sized to be greater than the body lumen, wherein the liner defines a suppleness such that expansion of the liner causes portions of the liner to fold upon itself while conforming against a tissue surface of the body lumen; and
infusing a cryoablative fluid or gas through a delivery lumen such that the fluid or gas passes into an infusion lumen, through the unobstructed openings, and into contact against an interior of the liner, wherein proximal translational of the delivery lumen relative to the infusion lumen from a first location increases the number of unobstructed openings, and distal translation of the delivery lumen relative to the infusion lumen from the first location decreases the number of unobstructed openings.
2. The method of claim 1 wherein the liner is sized to be at least 1.2 times greater than a uterine cavity into which the liner is inserted.
3. The method of claim 1 wherein expanding a liner comprises causing the portions of the liner to fold upon itself in an uncontrolled manner against the tissue surface.
4. The method of claim 1 wherein expanding a liner comprises causing the portions of the liner to fold upon itself in a controlled manner along pre-formed folds or pleats defined along the liner and against the tissue surface.
5. The method of claim 1 wherein expanding a liner comprises folding the portions to form between 1 to 3 layers of the liner.
6. The method of claim 1 wherein expanding a liner comprises folding the portions to a thickness of between 0.001 to 0.003 in. of the liner.
7. The method of claim 1 further comprising adjusting a position of the delivery lumen relative to the infusion lumen which is positioned through or along the elongate probe such that one or more openings defined along a length of the infusion lumen remain unobstructed by the delivery lumen.
8. The method of claim 1 wherein expanding a liner comprises infusing one or more puffs of air into the liner until the liner conforms to the body lumen.
9. The method of claim 1 wherein infusing a cryoablative fluid comprises infusing nitrous oxide or argon into the interior of the liner.