Multi-layer coaxial vaso-occlusive device

• US 8,764,788 B2
• Filed: 06/20/2011
• Issued: 07/01/2014
• Est. Priority Date: 07/31/2002
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Martinez, George
• Primary Examiner(s): NGUYEN, TUAN VAN
• Application Number:
  US13/164,446
• Publication Number:
  US 20110245863A1
• Time in Patent Office: 1,107 Days
• Field of Search: 606/108, 606/194, 606/198, 606/200, 623/1.11
• US Class Current: 606/200
• 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 17/12145 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 17/12177 comprising additional materials, e.g. thrombogenic, having filaments, having fibers or being coated
• 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 2017/0084 low friction A61B2017/00853 takes precedence
• CPC Class Codes: A61B 2017/00867 shape memory effect
• CPC Class Codes: A61B 2017/12054 Details concerning the detachment of the occluding device from the introduction device
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices
• CPC Class Codes: A61L 31/14 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61L 31/145 Hydrogels or hydrocolloids

Abstract

A vaso-occlusive device includes inner, intermediate, and outer elements arranged coaxially. The inner element is a filamentous element, preferably a microcoil. The intermediate element is made of a non-metallic material, preferably an expansile polymer. The outer element is substantially non-expansile and defines at least one gap or opening through which the intermediate element is exposed. In a preferred embodiment, when the intermediate element is expanded, it protrudes through the at least one gap or opening in the outer element and assumes a configuration with an undulating, convexly-curved outer surface defining a chain of arcuate segments, each having a diameter significantly greater than the diameter of the outer element. The expanded configuration of the intermediate element minimizes friction when the device is deployed through a microcatheter, thereby reducing the likelihood of buckling while maintaining excellent flexibility. The result is a device with enhanced pushability and trackability when deployed through a microcatheter.

Claims

1. A vaso-occlusive implant system insertable into a vascular malformation, comprising:

a flexible elongate delivery apparatus having a proximal end and a distal end;

a vaso-occlusive implant removably coupled to the distal end of the flexible elongate delivery apparatus comprising;

an elongate inner element formed from an expansile material that remains in an expanded state when located within a human body, and,

an outer element coaxially surrounding a length of the inner element, the outer element having a diameter substantially fixed from expansion and defining an open area between longitudinally-adjacent regions of the outer element that extends along a portion of the length of the inner element through which more than about 40% of a surface area of the inner element is exposed such that the expansile material is expandable through the open area and radially beyond the outer element.

2. The vaso-occlusive implant system of claim 1, wherein the inner element includes an expansile polymeric material.

3. The vaso-occlusive implant system of claim 2, wherein the expansile polymeric material comprises a hydrogel.

4. The vaso-occlusive implant system of claim 3, wherein the hydrogel is of a type that expands in response to a change in an environmental parameter.

5. The vaso-occlusive implant system of claim 4, wherein the environmental parameter is selected from the group consisting of temperature and pH.

6. The vaso-occlusive implant system of claim 1, wherein the outer element is formed of a helically-wound filament.

7. The vaso-occlusive implant system of claim 1, wherein the inner element comprises at least two concentric microcoils.

8. The vaso-occlusive implant system of claim 1, wherein the inner element defines a lumen containing a hollow, tubular core element.

9. The vaso-occlusive implant system of claim 1, wherein the inner element defines a lumen containing a substantially solid core element.

10. The vaso-occlusive implant system of claim 1, wherein at least one of the inner element and the outer element includes a material selected from the group consisting of at least one of a drug, a bioactive agent, a therapeutic compound, cellular material, genes, collagen, and protein.

11. A vaso-occlusive implant system comprising:

a flexible elongate delivery apparatus having a distal end;

a vaso-occlusive implant releasably coupled to the distal end of the flexible elongate delivery apparatus, comprising;

an expansile element having a surface area and remaining in an expanded state when in a physiological environment,

an outer element having a substantially non-expandable diameter and coaxially surrounding a length of the expansile element,

an open area formed between longitudinally-adjacent portions of said outer element, said open area exposing a portion of the surface area of the expansile element along the length of the expansile element, the outer element exposing more than about 40% of the surface area of the expansile element such that the expansile element is expandable through the open area and radially beyond the outer element.

12. The vaso-occlusive implant system of claim 11, wherein the expansile element includes an expansile polymeric material.

13. The vaso-occlusive implant system of claim 11, wherein the expansile element comprises a hydrogel.

14. The vaso-occlusive implant system of claim 11, wherein the outer element is a coil having spaces between each turn of the coil that defines the open area.

15. A vaso-occlusive implant system comprising:

a vaso-occlusive implant releasably coupled to a distal end of a flexible elongate delivery apparatus, comprising;

an expansile element having a surface area and maintaining a volumetrically expanded state when inside a human body,

an outer element having a substantially non-expandable diameter and being coaxially coiled around the expansile element to define an open space between loops of the outer element that expose more than about 40% of the surface area of the expansile element such that the expansile element is expandable through the open space between the loops and radially beyond the outer element.

16. The vaso-occlusive implant system of claim 15, wherein the expansile element comprises a hydrogel.

17. The vaso-occlusive implant system of claim 15, wherein the expansile element is a hydrogel expands in response to a change in an environmental parameter.

18. The vaso-occlusive implant system of claim 17, wherein the environmental parameter is selected from the group consisting of temperature and pH.