Medical device with slotted memory metal tube

• US 8,377,037 B2
• Filed: 10/06/2011
• Issued: 02/19/2013
• Est. Priority Date: 02/23/1996
• Status: Expired due to Fees

• Current Assignee: EVM Systems LLC (Acacia Research Corporation)
• Original Assignee: EVM Systems LLC (Acacia Research Corporation)
• Inventors: Sachdeva, Rohit C. L., Besselink, Petrus A.
• Primary Examiner(s): SHUMATE, VICTORIA PEARL
• Application Number:
  US13/267,512
• Publication Number:
  US 20120022577A1
• Time in Patent Office: 502 Days
• Field of Search: 606/198, 606/200, 604/105, 604/530, 604/531
• US Class Current: 604/531
• CPC Class Codes: A61B 1/00082 Balloons
• CPC Class Codes: A61B 1/0058 using shape-memory elements
• CPC Class Codes: A61B 1/015 Control of fluid supply or evacuation
• CPC Class Codes: A61B 1/018 for receiving instruments
• CPC Class Codes: A61B 1/307 for the urinary organs, e.g. urethroscopes, cystoscopes
• CPC Class Codes: A61B 1/3137 for examination of the interior of blood vessels
• CPC Class Codes: A61B 17/122 Clamps or clips , e.g. for the umbilical cord for the vas deferens A61F6/206
• CPC Class Codes: A61B 17/1285 for minimally invasive surgery
• CPC Class Codes: A61B 17/221 Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions surgical snare instruments A61B17/32056
• CPC Class Codes: A61B 17/32056 Surgical snare instruments for removing or smashing calculi A61B2017/2212; tonsillotomes A61B17/26
• CPC Class Codes: A61B 2017/00349 Needle-like instruments having hook or barb-like gripping means, e.g. for grasping suture or tissue A61B17/06066 takes precedence
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/00986 Malecots, e.g. slotted tubes, of which the distal end is pulled to deflect side struts
• CPC Class Codes: A61B 2017/2212 having a closed distal end, e.g. a loop
• CPC Class Codes: A61B 2017/2215 having an open distal end
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 2090/063 for measuring volume
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61B 5/6853 with a balloon
• 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 2002/30092 : using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0023 : operated at different temperatures whilst inside or touching the human body, heated or cooled by external energy source or cold supply
• CPC Class Codes: A61M 2025/0057 : Catheters delivering medicament other than through a conventional lumen, e.g. porous walls or hydrogel coatings
• CPC Class Codes: A61M 25/0013 : Weakening parts of a catheter tubing, e.g. by making cuts in the tube or reducing thickness of a layer at one point to adjust the flexibility
• CPC Class Codes: A61M 25/0138 : having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils
• CPC Class Codes: A61M 25/0158 : with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials
• CPC Class Codes: A61M 25/04 : in the body, e.g. expansible A61M25/10, A61M16/0488 take precedence
• CPC Class Codes: A61M 25/09 : Guide wires
• CPC Class Codes: A61M 29/02 : Dilators made of swellable material balloon catheters for angioplasty A61M25/104

Abstract

A series of medical instruments can be made with the use of shape memory tube with a transformation temperature that is above or below the ambient temperature. In the first case, the material behaves with the shape memory effect and in the second case the behavior is superelastic. The wall of the tube has been provided with a plurality of slots in specific places, often near or at the distal end of the instrument, and in specific arrangements which allow local variations in diameter, shape, and/or length. These variations can either be caused by the memory effect during temperature change or by superelastic behavior during change of the mechanical influences on the memory metal by the surrounding material.

Claims

1. A medical device for use within a tubular structure of a human body, the device comprising:

at least one monolithic memory metal tube configured and sized to be inserted within the tubular structure of the human body, the metal tube including at least one expandable section with a plurality of metal members separated by openings, the plurality of metal members being pre-programmed for a shape-memory effect based on a transformation temperature, the metal members expanding from a contracted shape to an expanded shape at or above the transformation temperature to form a retrieval basket for retrieving particles to be removed from the human body, each of the metal members being sufficiently rigid to substantially maintain the expanded shape of the expandable section when placed within and in contact with the tubular structure of the human body, the expandable section being free of interior structure that is axially movable within the expandable section to expand and/or contract the expandable section, the metal tube having a central longitudinal axis and a distal end, the expandable section being configured to catch a solid particle having a maximum cross-sectional dimension greater than a maximum cross-sectional dimension of the distal end of the metal tube transverse to the central longitudinal axis of the metal tube.

2. The device of claim 1, further comprising an outer tube surrounding the metal tube, the outer tube being slidable over the expandable section and configured to restrict the expandable section to the contracted shape.

3. The device of claim 1, wherein the expanded shape is a shape programmed using the memory effect of the metal tube.

4. The device of claim 3, wherein the programming of the shape is accomplished through a heat treatment of the metal tube.

5. The device of claim 1, wherein the tubular structure of the human body is a blood vessel.

6. The device of claim 1, wherein the tubular structure of the human body is a urethra.

7. The device of claim 1, wherein the metal tube has only a single lumen.

8. The device of claim 1, wherein the metal tube has a proximal end and a longitudinal passage with a central longitudinal axis coaxial to the central longitudinal axis of the metal tube.

9. The device of claim 1, wherein the openings are slots forming a slotted section, the slotted section being bounded by two non-slotted sections.

10. The device of claim 1, wherein the openings each have a mid-longitudinal axis and a complete perimeter surrounding the mid-longitudinal axis.

11. The device of claim 1, wherein the plurality of metal members are deformed in a martensitic state to the contracted shape.

12. The device of claim 1, wherein the metal members remain in the contracted shape below the transformation temperature independent of mechanical influences by any material external to the metal members.

13. The device of claim 1, wherein the plurality of metal members are activated by heat to form the expanded shape.

14. The device of claim 1, wherein the plurality of metal members are activated to form the expanded shape without the use of a delivery tool.

15. The device of claim 14, wherein the delivery tool is an outer tube.