Treatments using cryogenic ablation systems
Methods and apparatus for the treatment of a body cavity or lumen are described where a heated fluid and/or gas may be introduced through a catheter and into treatment area within the body contained between one or more inflatable/expandable members. The catheter may also have optional pressure and temperature sensing elements which may allow for control of the pressure and temperature within the treatment zone and also prevent the pressure from exceeding a pressure of the inflatable/expandable members to thereby contain the treatment area between these inflatable/expandable members. Optionally, a chilled, room temperature, or warmed fluid such as water may then be used to rapidly terminate the treatment session.
1. A tissue treatment system, comprising:
a handle having a housing;
an elongate probe extending from the housing and having a distal tip and a flexible length;
a liner expandably enclosing the probe;
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 proximal retraction 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; and
a controller which is programmed to infuse ambient air into the interior of the liner, and wherein the controller is further programmed to infuse a cryoablative fluid or gas into an interior of the liner via the infusion lumen for a period of time of up to 150 seconds such that the cryoablative fluid or gas is sprayed within the liner and into contact upon an interior surface of the liner.
2. The system of claim 1 wherein the ambient air is infused into the interior of the liner at a pressure of up to 85 mmHg and for a period of time of up to 20 seconds prior to infusing the cryoablative fluid or gas.
3. The system of claim 1 wherein the controller is further programmed to detect whether the pressure within the interior of the liner remains above 40 mmHg over a period of 5 seconds to determine whether a leak is present within the liner.
4. The system of claim 1 wherein the controller is further programmed to detect whether the pressure within the interior of the liner deviates by 20 mmHg or more over a period of 3 seconds to determine whether a leak is present within the liner.
5. The system of claim 1 wherein the controller is further programmed to infuse the cryoablative fluid or gas until a temperature of the interior of the liner is about −89° C.
6. The system of claim 1 wherein the controller is further programmed to cease infusing the cryoablative fluid or gas into the interior of the liner.
7. The system of claim 6 wherein the controller is further programmed to infuse air into the interior of the liner at a pressure of about 10 mmHg while the cryoablative fluid or gas remains within the interior and then vent for about 2 seconds to thaw tissue in contact with an exterior of the liner.
8. The system of claim 1 wherein the elongate probe defines an exhaust lumen for an ablative fluid.
9. The system of claim 1 wherein the one or more openings along the infusion lumen are defined opposite to one another along the infusion lumen.
10. The system of claim 1 further comprising a reservoir of a cryoablative fluid in fluid communication with the delivery lumen.
11. The system of claim 10 wherein the cryoablative fluid comprises nitrous oxide or argon.
12. The system of claim 1 further comprising a pump in fluid communication with the liner interior.
13. A method of treating tissue, comprising:
positioning an elongate probe into a body lumen to be treated;
infusing ambient air into an interior of a liner enclosing the probe to expand the liner into contact against the body lumen;
adjusting a position of a delivery lumen relative to an 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 are unobstructed, where proximal retraction 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;
infusing a cryoablative fluid or gas through the delivery lumen such that the fluid passes into the infusion lumen, through the unobstructed openings, and is sprayed into contact against the interior of the liner for a period of time of up to 150 seconds such that the body lumen is ablated.
14. The method of claim 13 wherein the infusion of the cryoablative fluid or gas is controlled via a controller.
15. The method of claim 13 further comprising ceasing the infusion of the cryoablative fluid or gas into the interior of the liner.
16. The method of claim 15 wherein the ambient air is infused into the interior of the liner at a pressure of up to 85 mmHg and for a period of time of up to 20 seconds.
17. The method of claim 13 further comprising detecting whether the pressure within the interior of the liner remains above 40 mmHg over a period of 5 seconds to determine whether a leak is present within the liner.
18. The method of claim 13 further comprising detecting whether the pressure within the interior of the liner deviates by 20 mmHg or more over a period of 3 seconds to determine whether a leak is present within the liner.
19. The method of claim 13 wherein infusing a cryoablative fluid or gas comprises infusing until a temperature of the interior of the liner is about −89° C.
20. The method of claim 13 further comprising infusing air into the interior of the liner at a pressure of about 10 mmHg while the cryoablative fluid or gas remains within the interior and then venting for about 2 seconds to thaw tissue in contact with an exterior of the liner.