Devices and methods for agent-assisted medical procedures
Various embodiments of bulking or cushioning agents or material and related medical devices and methods are disclosed. For example, a method of performing a medical procedure in a tract of a body may include injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, allowing the material to transition from the liquid phase to the gel phase in response to a raise in temperature of the material to approximately at or above the predetermined temperature, and performing a surgical procedure on the target site. The material may have the liquid phase at temperatures below a predetermined temperature and a gel phase at temperatures approximately at or above the predetermined temperature.
1. A method of performing a medical procedure in a tract of a body, comprising:
injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, the material having the liquid phase at temperatures below a predetermined temperature and having a gel phase at temperatures approximately at or above the predetermined temperature, wherein injecting the material causes a surface of the first tissue layer to protrude into the tract;
wherein after the injecting step, the material transitions from the liquid phase to the gel phase in response to a raise in temperature of the material to approximately at or above the predetermined temperature so that the surface of the first tissue layer remains protruded into the tract; and
performing a surgical procedure on the target site.
2. The method of claim 1 , further comprising removing the material from the target site, wherein the surface of the first tissue layer returns to a non-protruded state when the material is removed from the target site.
3. The method of claim 1 , wherein performing a surgical procedure comprises removing tissue from the target site.
4. The method of claim 1 , further comprising positioning an endoscope in the vicinity of a target site.
5. The method of claim 1 , wherein the predetermined temperature is a temperature of the body.
6. The method of claim 1 , wherein the material comprises polyoxyethylene-polyoxyproplyene block copolymers.
7. The method of claim 6 , wherein the molecular weights of the block copolymers ranges from approximately 5,000 to approximately 25,000.
8. The method of claim 1 , wherein the material remains in the gel phase for at least approximately 30 minutes.
9. The method of claim 1 , wherein the first tissue layer is a mucosal tissue layer and the second tissue layer is a submucosal tissue layer.
10. The method of claim 1 , wherein the tract is a gastrointestinal tract.
11. The method of claim 1 , wherein the material comprises poly(n-isopropyl acrylamide).
12. The method of claim 1 , wherein the material comprises thermally sensitive inorganic-organic hybrid gels.
13. The method of claim 1 , wherein the material comprises thermally sensitive block copolymer.
14. The method of claim 13 , wherein the thermally sensitive block copolymer comprises poly(N-isopropyl acrylamide-b-dl-lactide).
15. The method of claim 1 , wherein the material comprises polyvinyl alcohol.
16. The method of claim 1 , wherein the material is configured to be responsive to a change in pH level.
17. A method of performing a medical procedure in a tract of a body, comprising:
injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, the material having the liquid phase at temperatures below a predetermined temperature and having a gel phase at temperatures approximately at or above the predetermined temperature;
wherein after the injecting step, the material transitions from the liquid phase to the gel phase in response to a raise in temperature of the material to approximately at or above the predetermined temperature;
performing a surgical procedure on the target site; and
removing the material from the target site, wherein removing the material comprises injecting a cold fluid into the target site in contact with the material, allowing the material to transition from the gel phase to the liquid phase.
18. A method of performing a medical procedure in a tract of a body, comprising:
injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, the material having the liquid phase at pH levels below a predetermined pH level and having a gel phase at pH levels approximately at or above the predetermined pH level, wherein injecting the material causes a surface of the first tissue layer to protrude into the tract;
wherein after the injecting step, the material transitions from the liquid phase to the gel phase in response to a raise in pH of the material to approximately at or above the predetermined pH level so that the surface of the first tissue layer remains protruded into the tract; and
performing a surgical procedure on the target site.
19. A method of performing a medical procedure in a tract of a body, comprising:
injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, the material having the liquid phase at temperatures below a predetermined temperature and having a gel phase at temperatures approximately at or above the predetermined temperature;
wherein after the injecting step, the material transitions from the liquid phase to the gel phase in response to a raise in temperature of the material to approximately at or above the predetermined temperature;
performing a surgical procedure on the target site; and
removing the material from the target site, wherein removing the material comprises injecting a fluid into the target site in contact with the material, wherein the fluid has a temperature sufficiently low to cause the liquid to transition from the gel phase to the liquid phase.
20. A method of performing a medical procedure in a tract of a body, comprising:
injecting a material in a liquid phase proximate a target site between a first tissue layer and a second tissue layer, the material having the liquid phase at temperatures below a predetermined temperature and having a gel phase at temperatures approximately at or above the predetermined temperature, wherein injecting the material causes a surface of the first tissue layer to protrude into the tract;
wherein after the injecting step, the material transitions from the liquid phase to the gel phase in response to a raise in temperature of the material to approximately at or above the predetermined temperature so that the surface of the first tissue layer remains protruded into the tract; and
resecting tissue from the target site.
21. The method of claim 20 , further comprising positioning an endoscope in the vicinity of the target site.
22. The method of claim 20 , wherein the predetermined temperature is a temperature of the body.
23. The method of claim 20 , wherein the tissue that is resected is diseased tissue.
24. The method of claim 20 , wherein the resecting is performed with a resecting device delivered through a lumen of an endoscope.
25. The method of claim 20 , wherein the material remains in the gel phase for at least approximately 30 minutes.
26. The method of claim 20 , wherein the first tissue layer is a mucosal tissue layer and the second tissue layer is a submucosal tissue layer.
27. The method of claim 20 , wherein the tract is a gastrointestinal tract.
28. The method of claim 20 , wherein the resecting is performed with at least one of scissors, biopsy forceps, or a snare.
29. The method of claim 20 , wherein the material is configured to be responsive to a change in pH level.
30. The method of claim 20 , wherein injecting the material is performed with an injection needle.
31. The method of claim 30 , wherein the injection needle is delivered via a lumen of an endoscope.
32. The method of claim 20 , further comprising removing the material from the target site.
33. The method of claim 32 , wherein removing the material comprises injecting a fluid into the target site in contact with the material, wherein the fluid has a temperature sufficiently low to cause the liquid to transition from the gel phase to the liquid phase.
34. The method of claim 20 , further comprising removing the material from the target site, wherein the surface of the first tissue layer returns to a non protruded state when the material is removed from the target site.