Polyacrylamide hydrogel for the treatment of incontinence and vesicouretal reflex
The present invention relates to a bio-stable hydrogel for use in the treatment and prevention of incontinence and vesicouretal reflux. The hydrogel is obtainable by combining acrylamide and methylene bis-acrylamide in amounts to provide about 0.5 to 25% by weight polyacrylamide, based on the total weight of the hydrogel.
1. A method of treating anal incontinence comprising administering an endoprosthesis, which includes a hydrogel, to a mammal, said hydrogel comprising 0.5 to 25% by weight, based on the total weight of the hydrogel, of a polyacrylamide prepared by a method comprising combining acrylamide and methylene bis-acrylamide; wherein said hydrogel includes less than 50 ppm monomeric units, has a complex viscosity of about 2 to 50 Pas and has an elasticity modulus of about 1 to 200 Pa.
2. A method of treating anal incontinence comprising directly injecting a hydrogel into at least one of the conduits selected from the group consisting of a rectum and a colon, wherein the hydrogel comprises water or aqueous solution and about 0.5 to 25% by weight polyacrylamide having fewer than 50 ppm monomer units and having a complex viscosity of about 2 to 50 Pas and an elasticity modulus of about 1 to 200 Pa, the polyacrylamide prepared by combining acrylamide and methylene bis-acrylamide.
3. The method of claim 2 wherein the aqueous solution is a saline solution.
4. The method according to claim 1 or 2 , wherein the polyacrylamide is prepared by combining acrylamide and methylene bis-acrylamide in a molar ratio of 150:1 to 1000:1.
5. The method according to claim 1 or 2 , wherein the hydrogel comprises less than 15% by weight of the polyacrylamide, based on the total weight of the hydrogel.
6. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 1% by weight of the polyacrylamide, based on the total weight of the hydrogel.
7. The method according to claim 1 or 2 , wherein the hydrogel has a complex viscosity module of about 2 to 50 Pas.
8. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 80% by weight pyrogen-free water or saline solution.
9. The method according to claim 8 , wherein the pyrogen-free or water or saline solution is a saline solution.
10. The method according to claim 8 , wherein the pyrogen-free water or saline solution is pyrogen free water.
11. The method according to claim 1 , wherein the administering comprises injecting the hydrogel.
12. The method according to claim 11 , wherein the injecting of the hydrogel comprises injections at positions 10, 2, and 6 o'clock of the cross-sectional axis of the colon or rectum.
13. The method according to claim 1 or 2 , further comprising the inclusion of cells.
14. The method according to claim 13 , wherein the cells comprise stem cells.
15. The method according to claim 13 , wherein the cells allow for cellular engraftment to the surrounding tissue in the analis canalis.
16. The method according to claim 1 or 2 , wherein the hydrogel comprises less than 10% by weight of the polyacrylamide, based on the total weight of the hydrogel.
17. The method according to claim 1 or 2 , wherein the hydrogel comprises less than 7.5% by weight of the polyacrylamide, based on the total weight of the hydrogel.
18. The method according to claim 1 or 2 , wherein the hydrogel comprises less than 5% by weight of the polyacrylamide, based on the total weight of the hydrogel.
19. The method according to claim 1 or 2 , wherein the hydrogel comprises less than 3.5% by weight of the polyacrylamide, based on the total weight of the hydrogel.
20. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 1.6% by weight of the polyacrylamide, based on the total weight of the hydrogel.
21. The method according to claim 1 or 2 , wherein the hydrogel has a complex viscosity of about 2 to 40 Pas.
22. The method according to claim 1 or 2 , wherein the hydrogel has a complex viscosity of about 2 to 30 Pas.
23. The method according to claim 1 or 2 , wherein the hydrogel has a complex viscosity of about 2 to 20 Pas.
24. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 75% by weight pyrogen-free water or saline solution.
25. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 85% by weight pyrogen-free water or saline solution.
26. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 90% by weight pyrogen-free water or saline solution.
27. The method according to claim 1 or 2 , wherein the hydrogel comprises at least 95% by weight water or aqueous solution.
28. The method according to claim 1 or 2 , wherein the polyacrylamide is substantially comprised of cross-linked polyacrylamide.
29. The method according to claim 1 or 2 , wherein the polyacrylamide consists essentially of a polyacrylamide crosslinked with methylene bis-acrylamide.
30. The method according to claim 1 or 2 , wherein the hydrogel has an elasticity modulus of about 5 to 150 Pa.
31. The method according to claim 1 or 2 , wherein the hydrogel has an elasticity modulus of about 10 to 100 Pa.
32. The method according to claim 1 or 2 , wherein the elasticity modulus and the complex viscosity are related by a factor of 5.8 to 6.4.