Surgical retrieval baskets

• US 5,792,145 A
• Filed: 05/24/1996
• Issued: 08/11/1998
• Est. Priority Date: 11/21/1994
• Status: Expired due to Term

• Current Assignee: Boston Scientific Corporation
• Original Assignee: Boston Scientific Corporation
• Inventors: Weber, Tony E., Riley, James W., Bates, James S., Kline, Craig R., Wood, Gary D.
• Primary Examiner(s): Buiz, Michael Powell
• Assistant Examiner(s): Woo, Julian W.
• Application Number:
  US08/656,010
• Time in Patent Office: 809 Days
• Field of Search: 606/127, 606/128
• US Class Current: 606/127
• 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 2017/2212 having a closed distal end, e.g. a loop

Abstract

A retrieval basket comprises a plurality of wires normally encased in a compact form within a sheath whereupon displacement of the sheath to free a portion of the wires enables the wires to form an enlarged retrieval basket. The wires forming the retrieval basket are cold formed in a predetermined shape and are secured together in a predetermined fashion to define the retrieval basket.

Claims

1. A surgical extractor for removing an object from a body, said extractor comprising:

A) a sheath,

B) a plurality of rectangular cross-section wires normally encased in a compact form within said sheath whereupon relative displacement of said sheath and the wires frees a portion of the wires and enables the wires to form a basket for retrieving an object, each of said wires including a stress-relieved, cold formed section of predetermined shape, and

C) means for forming the wires together in a predetermined angular relationship that defines an enlarged portion of said basket between said sections.

2. A surgical extractor as recited in claim 1 wherein the wires are formed of a shape memory material.

3. A surgical extractor as recited in claim 2 wherein the shape memory material is stainless steel.

4. A surgical extractor as recited in claim 1 wherein said wires are heat treated to relieve stresses therein.

5. A surgical extractor as recited in claim 1 wherein plurality of wires comprises an odd number of wires.

6. A surgical extractor as recited in claim 5 wherein each said wire is formed in a plane whereby a basket defined by said wires is a straight wire basket.

7. A surgical extractor as recited in claim 6 wherein each of said wires extending from the secured portions defines a closed loop.

8. A surgical extractor as recited in claim 5 wherein each of said wires is formed as a turn in a helix whereby a basket defined by said wires is a helical retrieval basket.

9. A surgical extractor as recited in claim 2 wherein each of said cold formed sections extends radially from an axis through opposed ends of said wire, said wires collectively defining the enlarged portion of said basket.

10. A surgical extractor as recited in claim 2 additionally comprising means for moving said sheath axially to free said wires.

11. A surgical extractor as recited in claim 2 wherein said sheath means extends between proximal and distal ends, said extractor additionally comprising means for moving said sheath means proximally to free said wires.

12. A surgical extractor for removing an object from a body comprising:

A) handle means extending along an axis at a proximal portion of said extractor for operating said extractor, said handle means having base means for being grasped by a physician and slider means for reciprocating along the axis with respect to said base means,

B) retrieval basket means connected to said base means for forming a basket distally of said handle means, said retrieval basket comprising a plurality of individual rectangular cross-section wires of a shape memory material having first and second ends and a central, cold-formed section of a predetermined shape and means for fixing the individual wires in predetermined angular relationships to define an enlarged basket,

C) sheath means connected to said slider means and axially displaceable between first and second positions with respect to said retrieval basket means whereby said sheath means retains said wires in a compact form within said sheath means in a first position and exposes said wires in the second position thereby to enable said wires to expand to said basket.

13. A surgical extractor as recited in claim 12 wherein each of said wires includes a distal section that extends radially from an axis through the first and second ends thereof.

14. A surgical extractor as recited in claim 13 wherein each of said wires is wound along a turn in a helix.

15. A surgical extractor as recited in claim 13 wherein said plurality of wires is odd.

16. A surgical extractor as recited in claim 13 wherein each of said wires has a planar shape to form a straight wire basket.

17. A surgical extractor as recited in claim 16 wherein said plurality of wires is odd.

18. A surgical extractor as recited in claim 12 wherein each of said wires has essentially no internal stress wherein said wires are expanded.

19. A surgical extractor as recited in claim 12 wherein each of said wires is composed of a shape memory material.

20. A surgical extractor as recited in claim 19 wherein said shape memory material is stainless steel.

21. A surgical extractor as recited in claim 12 wherein said sections of each of said wires are formed in a loop centered about an axis of said enlarged basket with the first and second ends of said wires extending in the same direction along the axis.

22. An extractor for removing an object from a body comprising:

A) retrieval basket means comprising;

(i) an odd number of individual flat, shape memory wires having first and second ends and an intermediate section preformed in a shape corresponding to the desired shape of the basket and characterized by having essentially no internal stresses in the preformed shape, and

(ii) means for fixing said first and second ends of said wires to establish an angular spacing between each of said wires whereby the intermediate sections of the wires lie in angularly spaced radial planes,

B) positioning means having proximal and distal ends, said distal end being attached to the fixing means at the first ends of said wires for positioning said retrieval basket means in the body, and

C) a sheath carried by said positioning means, said sheath, in a first position, overlying said wires thereby to compact the wires and, in a second position, freeing said wires to expand into the shape of the retrieval basket.

23. An extractor as recited in claim 22 wherein said odd number of wires consists of three angularly displaced, stainless steel wires.

24. An extractor as recited in claim 22 wherein said odd number of wires consists of five angularly displaced, stainless steel wires.