Embolization

• US 7,666,333 B2
• Filed: 10/24/2007
• Issued: 02/23/2010
• Est. Priority Date: 06/01/2004
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Buiser, Marcia S., Lanphere, Janel L., Casey, Thomas V.
• Primary Examiner(s): Theisen; Mary Lynn F
• Application Number:
  US11/923,009
• Publication Number:
  US 20080041715A1
• Time in Patent Office: 853 Days
• Field of Search: None
• US Class Current: 264/11
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12104 in an air passage
• CPC Class Codes: A61B 17/12109 in a blood vessel
• CPC Class Codes: A61B 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12186 liquid materials adapted to be injected
• CPC Class Codes: A61B 17/1219 expandable in contact with liquids
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61J 3/07 into the form of capsules or similar small containers for oral use
• CPC Class Codes: B01J 13/046 combined with gelification or coagulation

Abstract

Embolization, as well as related particles and methods, are described.

Claims

1. A method of making particles, the method comprising:

combining a plurality of streams of fluid to form drops, the plurality of streams of fluid comprising first and second streams, the first stream comprising a polymer, and the second stream comprising a gelling precursor;

after forming the drops, converting the gelling precursor from a solution into a gel; and

removing at least some of the gel from the particles to provide particles having an arithmetic mean diameter of from about ten microns to about 3,000 microns.

2. The method of claim 1, further comprising flowing the first stream through a first orifice defined by a nozzle to form the first stream.

3. The method of claim 2, wherein the first orifice has a diameter of from about 50 microns to about 1,000 microns.

4. The method of claim 2, wherein the first orifice has a diameter of from about 50 microns to about 300 microns.

5. The method of claim 2, further comprising flowing the gelling precursor through a second orifice defined by the nozzle to form the second stream.

6. The method of claim 5, wherein the second orifice has a first diameter of from about 50 microns to about 1,000 microns.

7. The method of claim 5, wherein the second orifice has a first diameter of from about 100 microns to about 600 microns.

8. The method of claim 5, wherein the second orifice has a second diameter of from about 50 microns to about 1,000 microns.

9. The method of claim 5, wherein the second orifice has a second diameter of from about 100 microns to about 600 microns.

10. The method of claim 5, wherein the first orifice has a diameter and the second orifice has a diameter, and a difference between the diameter of the second orifice and the diameter of the first orifice is at least about 50 microns.

11. The method of claim 5, wherein the first orifice is disposed within the second orifice.

12. The method of claim 11, wherein the first orifice and the second orifice are concentric.

13. The method of claim 12, wherein the first orifice is disposed at a vertical distance of about one millimeter from the second orifice.

14. The method of claim 5, wherein the first material flows through the first orifice at a rate of from about two milliliters per minute to about ten milliliters per minute.

15. The method of claim 14, wherein the second material flows through the second orifice at a rate of from about two milliliters per minute to about 20 milliliters per minute.

16. The method of claim 1, wherein the first stream and the second stream are immiscible.

17. The method of claim 1, wherein the first stream and the second stream are concentric.

18. The method of claim 1, wherein the first stream forms an interior region of the drops and the second stream forms a surface region of the drops.

19. The method of claim 1, wherein a viscosity of the polymer is greater than a viscosity of the gelling precursor.

20. The method of claim 1, wherein a viscosity of the gelling precursor is greater than a viscosity of the polymer.

21. The method of claim 1, wherein the particles contain pores.

22. The method of claim 21, wherein the particles have a first density of pores in an interior region and a second density of pores at a surface region, the first density being different from the second density.

23. The method of claim 22, wherein the first density is greater than the second density.

24. The method of claim 21, wherein the particles have a first average pore size in an interior region and a second average pore size at a surface region, the first average pore size being different from the second average pore size.

25. The method of claim 24, wherein the first average pore size is greater than the second average pore size.

26. The method of claim 1, wherein the plurality of streams is two streams.

27. The method of claim 1, wherein the plurality of streams comprises at least three streams.

28. The method of claim 1, wherein forming the drops includes exposing the plurality of streams to a periodic disturbance.

29. The method of claim 28, wherein the periodic disturbance is provided by vibrating the plurality of streams.

30. The method of claim 1, wherein forming the drops includes establishing an electrostatic potential between the plurality of streams and a vessel configured to receive the drops.

31. A method of making particles, the method comprising:

combining a first stream including polyvinyl alcohol and a second stream including a gelling precursor to form drops; and

forming particles from the drops,

wherein the particles comprise cross-linked polyvinyl alcohol, and the particles contain pores.

32. The method of claim 31, wherein the particles have an arithmetic mean diameter of from about ten microns to about 3,000 microns.

33. A method of making particles, the method comprising:

forming a plurality of streams of fluid from a plurality of orifices, the plurality of streams of fluid comprising first and second streams, the first stream comprising a polymer, and the second stream comprising a gelling precursor;

combining the plurality of streams of fluid to form drops; and

forming particles from the drops,

wherein the particles contain pores and a first orifice of the plurality of orifices has a diameter of from about 50 microns to about 1000 microns, and a second orifice of the plurality of orifices has a first diameter of from about 50 microns to about 1000 microns and a second diameter of from about 50 microns to about 1000 microns, wherein the second diameter of the second orifice is different from the diameter of the first orifice.

34. The method of claim 33, wherein the first orifice has a diameter of from about 50 microns to about 300 microns.

35. The method of claim 33, wherein the second orifice has a first diameter of from about 100 microns to about 600 microns.

36. The method of claim 35, wherein the second orifice has a second diameter of from about 100 microns to about 600 microns.

37. The method of claim 33, wherein a difference between the second diameter of the second orifice and the diameter of the first orifice is at least about 100 microns.

38. The method of claim 33, wherein the first orifice and the second orifice are concentric.