Filamentous embolic device with expansile elements

• US 20020120276A1
• Filed: 05/29/2001
• Published: 08/29/2002
• Est. Priority Date: 10/04/1999
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Cox, Brian J., Cruise, Gregory M., Constant, Michael, Greene, George R. Jr.
• Granted Patent: US 6,602,261 B2
• Time in Patent Office: Days
• US Class Current: 606/108
• 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 17/12113 within an aneurysm
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/1215 comprising additional materials, e.g. thrombogenic, having filaments, having fibers, being coated
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 17/12163 having a string of elements connected to each other
• CPC Class Codes: A61B 17/1219 expandable in contact with liquids
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable or resorptive
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/145 Hydrogels or hydrocolloids
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: B29C 70/74 Moulding material on a relatively small portion of the preformed part, e.g. outsert moulding B29C70/845 takes precedence
• CPC Class Codes: B29L 2031/7542 Catheters

Abstract

An embolization device includes one or more expansible, hydrophilic embolizing elements non-releasably carried along the length of a filamentous carrier that is preferably made of a very thin, highly flexible filament or microcoil of nickel/titanium alloy. At least one expansile embolizing element is non-releasably attached to the carrier. A first embodiment includes a plurality of embolizing elements fixed to the carrier at spaced-apart intervals along its length. In a second embodiment, an elongate, continuous, coaxial embolizing element is non-releasably i- fixed to the exterior surface of the carrier, extending along a substantial portion of the length of the carrier proximally from a distal tip. In either of the embodiments, the embolizing elements may be made of a hydrophilic, macroporous, polymeric, hydrogel foam material. In the second embodiment, the elongate embolizing element is preferably made of a porous, environmentally-sensitive, expansile hydrogel that expands, after a predetermined time delay, in response to a change in an environmental parameter, such as pH or temperature.

Claims

1. A vascular embolization device, comprising:

a flexible, filamentous carrier having a distal tip and an exterior surface; and

an elongate, continuous, coaxial embolizing element non-releasably fixed to the exterior surface of the carrier along a substantial portion of the length of the carrier proximally from the distal tip.

2. The embolization device of claim 1, wherein the embolizing element is formed of a stretch-resistant, biocompatible polymer.

3. The embolization device of claim 1, wherein the embolizing element is formed of an expansile, hydrophilic polymer.

4. The embolization device of claim 1, wherein the carrier comprises a material that is visible under X-rays.

5. The embolization device of claim 3, wherein the polymer is an environmentally-sensitive polymer that changes its physical character in response to a change in an environmental parameter selected from the group consisting of temperature and pH.

6. The embolization device of claim 3, wherein the embolizing element is expansible by a volumetric expansion factor of between about 2X and about 100X.

7. The embolization device of claim 1, wherein the embolizing element is radiopaque.

8. The embolization device of claim 1, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained

9. The embolization device of claim 8, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an avoid.

10. A vascular embolization device, comprising:

an elongate, flexible, filamentous carrier; and

an embolizing element non-releasably fixed to the carrier, the embolizing element being formed from an expansile polymer that expands in response to a change in an environmental parameter selected from the group consisting of temperature and pH after a predetermined time interval.

11. The embolization device of claim 10, wherein the polymer is a porous hydrogel.

12. The embolization device of claim 10, wherein the embolizing element comprises an elongate, continuous, coaxial embolizing element non-releasably fixed to the exterior surface of the carrier along a substantial portion of the length of the carrier.

13. The embolization device of claim 10, wherein the embolizing element comprises a plurality of expansile polymer fibers attached to the carrier.

14. The embolization device of claim 10, wherein the embolizing element is radiopaque.

15. The embolization device of claim 10, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained.

16. The embolization device of claim 15, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

18. The embolization device of claim 17, wherein the polymer hydrogel is of a type that expands in response to a change in an environmental parameter selected from the group consisting of temperature and pH after a predetermined time interval.

19. The embolization device of claim 17, wherein the carrier is configured in the form of a multi-looped structure that may assume a three-dimensional shape when unconstrained

20. The embolization device of claim 19, wherein the three-dimensional shape is selected from the group consisting of a sphere, a helix, and an ovoid.

17. A vascular embolization device, comprising:

an elongate, flexible, filamentous carrier of predetermined length; and

a plurality of expansile fibers fixed to the carrier at spaced intervals along the length of the carrier, the fibers being formed from an expansile polymer hydrogel.