Claims for Patent: 8,734,833

Summary for Patent: 8,734,833

Title:	Therapeutic foam
Abstract:	A therapeutic foam for the treatment of, inter alia, varicose veins comprises a sclerosing solution foamed with a physiological gas such as carbon dioxide, oxygen or a mixture thereof. The foam has a nitrogen content of less than 0.8%. It may be generated using a pressurized canister system incorporating a fine mesh of micron dimensions through which the gas and sclerosing liquid are passed to make the foam. Alternatively, the foam may be generated by passing gas and solution between two syringes through a fine mesh. Techniques are described for minimizing the amount of nitrogen in a canister or syringe based product. A technique for generating and delivering foam simultaneously using a syringe based device is also disclosed.
Inventor(s):	Wright; David Dakin Iorwerth (Henley on Thames, GB), Harman; Anthony David (Henley on Thames, GB), Robinson; Nikki (Newmachar, GB), Hodges; Garry (Welwyn, GB), Kadar; Adil (London, GB), Moggridge; Geoffrey D. (Cambridge, GB), Liew; Hugh Van (Barnstable, MA)
Assignee:	BTG International Ltd. (GB)
Application Number:	13/667,296
Patent Claims:	1. A foam comprising a liquid phase and a gas phase wherein the liquid phase comprises at least one sclerosing agent and the gas phase consists essentially of 0.01% to 0.8% vol/vol nitrogen, 10% to 99.99% vol/vol carbon dioxide, and the remaining gas, if any, consisting essentially of oxygen. 2. The foam of claim 1, wherein the nitrogen is present in an amount ranging from 0.01% to 0.7%. 3. The foam of claim 1, wherein the nitrogen is present in an amount ranging from 0.01% to 0.6%. 4. The foam of claim 1, wherein the foam has a density of less than 0.25 g/ml and a half life of greater than 100 secs. 5. The foam of claim 1, wherein the foam has a half of at least 120 seconds. 6. The foam of claim 1, wherein the foam has a half life of at least 150 seconds. 7. The foam of claim 1, wherein the foam has a half life of at least 180 seconds. 8. The foam of claim 1, wherein the foam has a density ranging from 0.07 to 0.22 g/ml. 9. The foam of claim 1, wherein the foam has a density ranging from 0.07 to 0.19 g/ml. 10. The foam of claim 1, wherein the foam has a density ranging from 0.07 to 0.16 g/ml. 11. The foam of claim 1, wherein the foam has a density ranging from 0.08 to 0.14 g/ml. 12. The foam of claim 1, wherein the at least one sclerosing agent is chosen from polidocanol, glycerol and sodium tetradecyl sulphate. 13. The foam of claim 1, wherein the at least one sclerosing agent is polidocanol. 14. The foam of claim 13, wherein the polidocanol is present in a concentration ranging from 0.5% to 4% vol/vol in the liquid phase. 15. A foam comprising: a liquid phase and a gas phase, wherein the liquid phase comprises at least one sclerosing agent; and the gas phase consists essentially of 0.01% to 0.8% vol/vol nitrogen, about 10% to about 99.99% vol/vol carbon dioxide, and the remaining gas, if any, consisting essentially of oxygen. 16. The foam of claim 15, wherein the nitrogen is present in an amount ranging from 0.01% to 0.7%. 17. The foam of claim 15, wherein the nitrogen is present in an amount ranging from 0.01% to 0.6%. 18. The foam of claim 15, wherein the foam has a density of less than 0.25 g/ml and a half life of greater than 100 secs. 19. The foam of claim 15, wherein the foam has a half life of at least 120 seconds. 20. The foam of claim 15, wherein the foam has a half life of at least 150 seconds. 21. The foam of claim 15, wherein the foam has a half life of at least 180 seconds. 22. The foam of claim 15, wherein the foam has a density ranging from 0.07 to 0.22 g/ml. 23. The foam of claim 15, wherein the foam has a density ranging from 0.07 to 0.19 g/ml. 24. The foam of claim 15, wherein the foam has a density ranging from 0.07 to 0.16 g/ml. 25. The foam of claim 15, wherein the foam has a density ranging from 0.08 to 0.14 g/ml. 26. The foam of claim 15, wherein the at least one sclerosing agent is chosen from polidocanol, glycerol and sodium tetradecyl sulphate. 27. The foam of claim 15, wherein the at least one sclerosing agent is polidocanol. 28. The foam of claim 27, wherein the polidocanol is present in a concentration ranging from 0.5% to 4% vol/vol in the liquid phase. 29. A foam comprising: a liquid phase and a gas phase, wherein the liquid phase comprises at least one sclerosing agent; and the gas phase consists essentially of 0.01% to 0.8% vol/vol nitrogen, at least 50% vol/vol carbon dioxide, and the remaining gas, if any, consisting essentially of oxygen. 30. The foam of claim 29, wherein the nitrogen is present in an amount ranging from 0.01% to 0.7%. 31. The foam of claim 29, wherein the nitrogen is present in an amount ranging from 0.01% to 0.6%. 32. The foam of claim 29, wherein the foam has a density of less than 0.25 g/ml and a half life of greater than 100 secs. 33. The foam of claim 29, wherein the foam has a half life of at least 120 seconds. 34. The foam of claim 29, wherein the foam has a half life of at east 150 seconds. 35. The foam of claim 29, wherein the foam has a half life of at least 180 seconds. 36. The foam of claim 29, wherein the foam has a density ranging from 0.07 to 0.22 g/ml. 37. The foam of claim 29, wherein the foam has a density ranging from 0.07 to 0.19 g/ml. 38. The foam of claim 29, wherein the foam has a density ranging from 0.07 to 0.16 g/ml. 39. The foam of claim 29, wherein the foam has a density ranging from 0.08 to 0.14 g/ml. 40. The foam of claim 29, wherein the at least one sclerosing agent is chosen from polidocanol, glycerol and sodium tetradecyl sulphate. 41. The foam of claim 29, wherein the at least one sclerosing agent is polidocanol. 42. The foam of claim 41, wherein the polidocanol is present in a concentration ranging from 0.5% to 4% vol/vol in the liquid phase.