Bistable spring construction for a stent and other medical apparatus

• US 9,241,782 B2
• Filed: 11/08/2010
• Issued: 01/26/2016
• Est. Priority Date: 01/24/1997
• Status: Expired due to Term

• Current Assignee: CeloNova Stent, Inc.
• Original Assignee: CeloNova Stent, Inc.
• Inventors: Besselink, Petrus Antonius
• Primary Examiner(s): Isabella, David
• Assistant Examiner(s): Ganesan, Suba
• Application Number:
  US12/941,591
• Publication Number:
  US 20110208291A1
• Time in Patent Office: 1,905 Days
• Field of Search: 623/1.1, 623/1.12, 623/1.15, 623/1.16, 623/1.17, 623/1.18, 623/1.19, 623/1.2, 623/1.3, 623/23.64, 623/23.7
• US Class Current: 1/1
• CPC Class Codes: A61B 17/11 for performing anastomosis; Buttons for anastomosis
• CPC Class Codes: A61B 2017/1107 for blood vessels
• CPC Class Codes: A61F 2/0004 Closure means for urethra or rectum, i.e. anti-incontinence devices or support slings against pelvic prolapse
• CPC Class Codes: A61F 2/0009 placed in or outside the body opening close to the surface of the body plugging an opening in the wall of a hollow or tubular organ A61B17/0057
• CPC Class Codes: A61F 2/0022 placed deep in the body opening occluding blood vessels by internal devices A61B17/12022
• CPC Class Codes: A61F 2/02 Prostheses implantable into the body closure means for urethra or rectum or for artificial body openings therefor A61F2/0004
• CPC Class Codes: A61F 2/042 Urinary bladders
• CPC Class Codes: A61F 2/064 with special features to facilitate anastomotic coupling anastomosis of natural blood vessels A61B17/11
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/047 Urethrae
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/9155 Adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: F16K 31/003 operated without a stable intermediate position, e.g. with snap action F16K31/56 takes precedence

Abstract

The present invention is directed to bistable cells and their use in devices, particularly medical devices such as stents, clamps and valves. An expandable stent formed of a plurality of bistable cells is described. The stent has two or more stable configurations, including a first stable configuration with a first diameter and a second stable configuration with a second, larger diameter. A valve comprising a bistable cell for use in eliminating incontinence is also disclosed.

Claims

1. A medical device including at least one unit cell formed from at least two segments comprising a first relatively rigid arcuate segment;

and a second relatively flexible arcuate segment, the first and second arcuate segments mechanically connected so that the first segment hinders the deformation of the second segment in a first direction, whereby the unit cell can be deformed in a second direction substantially perpendicular to the first direction, between a first substantially stable collapsed shape and a second substantially stable expanded shape,

wherein a majority of the first relatively rigid arcuate segments are directly connected to the second relatively flexible arcuate segments of an adjacent unit cell by means of joints.

2. A medical device as in claim 1, the unit cell having an equilibrium position, the unit cell having a symmetrical load-displacement characteristic around the equilibrium position.

3. A medical device as in claim 1, the unit cell having an equilibrium position, the unit cell having an asymmetrical load-displacement characteristic around the equilibrium position, the most stable shape of the unit cell being the expanded shape.

4. A medical device as in claim 1, the unit cell having an equilibrium position, the unit cell having an asymmetrical load-displacement characteristic around the equilibrium position, the most stable shape of the unit cell being the collapsed shape.

5. A medical device as in claim 1 in the form of a clip for holding one or more body parts.

6. A medical device as in claim 1 in the form of an expander for holding one or more body parts apart.

7. A medical device as in claim 1 comprising a plurality of unit cells, each unit cell characterized by a point of maximum deflection of the second relatively flexible arcuate segment, wherein the joints are located at or near the point of maximum deflection of each of the second relatively flexible arcuate segments.

8. An expandable, hollow, stent, having the structure of claim 7, the stent having a plurality of stable configurations with different diameters, the stent having a fully collapsed configuration in which the stent has a minimum diameter and the stent having a fully expanded configuration in which the stent has a maximum diameter.

9. The stent of claim 8 made at least in part of a material selected from the group consisting of plastic deformable materials, elastically deformable materials, polymers, metals, composites, shape memory materials exhibiting superelastic behavior, shape memory materials exhibiting temperature sensitive behavior and combinations thereof.

10. A multiple unit stent comprised of a plurality of stents as in claim 8, the stents connected in the axial direction by flexible joints.

11. A stent as in claim 10 where the cells are balloon expandable, self-expanding or temperature sensitive.

12. A stent as claimed in claim 8 the stent being tubular and having one or more tapered cylindrical sections.

13. The medical device of claim 1 made at least in part of a material selected from the group consisting of plastic deformable materials, elastical deformable materials, polymers, metals, composites, shape memory materials exhibiting superelastic behavior, shape memory materials exhibiting temperature sensitive behavior and combinations thereof.

14. A stent as in claim 1 wherein the flexibility of the stent between adjacent unit cells in a tangential and/or axial direction is increased by disconnecting several unit cells from their adjacent unit cells by cutting a center of one or more joints.

15. A medical device including at least one unit cell formed from at least two segments comprising a first relatively rigid arcuate segment;

and a second relatively flexible arcuate segment, the first and second arcuate segments mechanically connected so that the first segment hinders the deformation of the second segment in a first direction, whereby the unit cell can be deformed in a second direction substantially perpendicular to the first direction, between a first substantially stable collapsed shape and a second substantially stable expanded shape, wherein the first and second arcuate segments are connected by elastic hinges.

16. The medical device of claim 15, exhibiting increased flexibility wherein the first and second arcuate segments of the unit cells are connected by elastic hinges.

17. The medical device of claim 15, wherein the hinges are made of plastically deformable material.

18. A medical device as in claim 15, wherein adjacent unit cells in a tangential and/or axial direction are joined by plastic or elastic deformable hinges thereby increasing the flexibility between adjacent unit cells in a tangential and/or axial direction.

19. The medical device of claim 15, wherein the medical device exhibits increased flexibility via the elastic hinges.

20. A medical device including at least one unit cell formed from a first rigid arcuate segment and a second flexible arcuate segment, the first and second arcuate segments mechanically connected so that the first segment hinders the deformation of the second segment in a first direction, whereby the unit cell can be deformed in a second direction substantially perpendicular to the first direction, between a first substantially stable collapsed shape and a second substantially stable expanded shape,

wherein a majority of the first rigid arcuate segments are directly connected to the second flexible arcuate segments of an adjacent unit cell by means of joints.