Flexible MEMS actuated controlled expansion stent

• US 7,097,658 B2
• Filed: 08/22/2002
• Issued: 08/29/2006
• Est. Priority Date: 08/22/2001
• Status: Active Grant

• Current Assignee: Hasan Semih Oktay
• Original Assignee: Hasan Semih Oktay
• Inventors: Oktay, Hasan Semih
• Primary Examiner(s): Pellegrino, Brian E.
• Application Number:
  US10/226,706
• Publication Number:
  US 20030040791A1
• Time in Patent Office: 1,468 Days
• Field of Search: 623/1.11, 623/1.12, 623/1.15, 623/1.18, 623/1.2, 606/191, 606/192, 606/194, 606/198, 128/899
• US Class Current: 623/1.2
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped

Abstract

An automatically controlled expansion stent having an expansible stent body, actuation means for expanding the stent body, and control means for actively controlling the actuation means. The stent body is substantially tubular and includes material layers covering a plurality of radial expansion trusses. The stent employs MEMS motors under the control of a programmable logic device to expand the trusses and the stent body. Force from the motor is communicated to the expansion trusses through interconnects, which pivotally connect the trusses and provide channels for pull wires extending from the motors to the trusses. The trusses comprise a plurality of hinged links which produce symmetrical expansion of the stent body when actuated by the MEMS motor.

Claims

1. An automatically controlled expansion stent, comprising:

a substantially tubular expansible stent body comprising a first and a second end, inner and outer wall surfaces, and a first diameter that permits intraluminal delivery;

at least two radial expansion trusses for expanding said stent body, said expansion trusses composed of a plurality of hinged links which allow symmetrical expansion of the radial expansion trusses, and further including a plurality of interconnects interposed between said radial expansion trusses;

actuation means for selectively expanding said stent body mechanically, wherein the expansion of said stent body does not involve a plastic deformation process or utilize shape memory material characteristics;

control means for actively controlling said actuation means;

wherein said hinged links comprise a combination of triangular shaped links, angulated links, and notched angulated links, each attached to an adjoining link by hinged pivot points.

2. The stent of claim 1, wherein said interconnects are arcuate, and wherein said interconnects form a closed cylindrical body when said stern is in a collapsed configuration and are evenly spaced apart when said stent is in a partially expanded or fully expanded configuration.

3. The stent of claim 2, wherein said interconnects each have an interconnect ball joint and shaft at each end and attaches to said radial expansion truss at a socket-shaped pivot point on the radial expansion truss.

4. An automatically controlled expansion stent, comprising:

an expansible stent body;

at least one Micro-Electro-Mechanical-System (MEMS) motor operatively connected to said stent body for selectively expanding said stent body mechanically, wherein the expansion of said stent body does not involve a plastic deformation process or utilize shape memory material characteristics; and

control means for actively controlling said MEMS motor, wherein said control means is electrically connected to said MEMS motors and comprises a device selected from the group consisting of a PLC and a microprocessor.

5. An automatically controlled expansion stent, comprising:

an expansible substantially tubular stent body having first and second ends, inner and outer wall surfaces, and a first diameter that permits intraluminal delivery;

at least one Micro-Electro-Mechanical-System (MEMS) motor operatively connected to said stent body for expanding said stent body;

control means for actively controlling said MEMS motor;

wherein said tubular body is enlarged by the use of at least two radial expansion trusses composed of a plurality of hinged links which allow symmetrical expansion of the radial expansion trusses, and further including a plurality of interconnects interposed between said radial expansion trusses; and

wherein each of said MEMS motors is connected to at least one radial expansion truss through a pull wire extending through at least one of said interconnects which attaches to said radial expansion truss, and wherein as force is exerted on said pull wire by said MEMS motor, said radial expansion truss is expanded.