Medical retrieval basket

• US 6,190,394 B1
• Filed: 11/05/1999
• Issued: 02/20/2001
• Est. Priority Date: 11/05/1999
• Status: Expired due to Term

• Current Assignee: Annex Medical, Inc.
• Original Assignee: Annex Medical, Inc.
• Inventors: Lind, Stuart J., Karels, Eugene C.
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US09/435,199
• Time in Patent Office: 473 Days
• Field of Search: 606/127, 606/128, 606/106
• 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 medical retrieval basket for removing objects such as urinary and biliary calculi from the body. The basket comprises an elongated flexible tube and a cage which is extendible from the distal end of the tube and can be collapsed by withdrawing into the tube by means of an actuation cable which passes through the tube. The cage consists of a plurality of flexible elements which are outwardly disposed to form a space for entrapping objects. The flexible elements are constructed of a shape memory material, allowing the cage to resume its original configuration when extended from the tube. The configuration of the cage is such that by means of rotating the cage, differing sizes, cross sectional shapes and/or spacing of the flexible elements may be presented to a given portion of the object to be removed. Rotation of the cage is controlled more precisely using an actuation cable constructed of nickel titanium.

Claims

1. A medical retrieval basket for extracting an object from a body comprising:

a cage having a longitudinal axis and an expandable portion consisting of a plurality of flexible elements which are outwardly disposed to form a space for entrapping said object,

a tubular means for the collapsing of said flexible elements when withdrawn into said tubular means,

an actuation means to enable the movement of said flexible elements into and out of said tubular means and to enable rotation of said cage,

the impivement wherein the flexible elements, when outwardly disposed, include a plurality of flexible elements, forming a plural set, which are spaced relatively closely to each other and spaced relatively far from adjacent flexible elements outside of the plural set, the flexible elements, when outwardly disposed, also including a single flexible element spaced relatively far from adjacent flexible elements, wherein there are a plurality of plural sets and at least one single flexible element spaced around said longitudinal axis, whereby rotation of said actuation means will cause rotation of said cage in order to present either a single flexible element or a said plural set to the object being removed.

2. The medical retrieval basket of claim 1 wherein the actuation means is a cable containing a shape memory alloy.

3. The medical retrieval basket of claim 1 further including a substantially cylindrical tip at the distal end of said cage.

4. The medical retrieval basket of claim 1 wherein said flexible elements are in an approximately helical configuration.

5. The medical retrieval basket of claim 1 wherein said flexible elements are metallic with the materials being selected from a group consisting of stainless steel and shape memory alloys .

6. A medical retrieval basket for extracting an object from a body comprising:

a cage having a longitudinal axis and an expandable portion consisting of a plurality of flexible elements which are outwardly disposed to form a space for entrapping said object,

a tubular means for the collapsing of said flexible elements when withdrawn into said tubular means,

an actuation means to enable the movement of said flexible elements into and out of said tubular means and to enable rotation of said cage,

the improvement wherein each of said flexible elements has a predetermined cross sectional shape and said cage incorporates a plurality of the flexible element cross sectional shape, whereby rotation of said actuation means about said longitudinal axis will cause rotation of said cage in order to present differing said flexible element cross sectional shape to the object being removed.

7. The medical retrieval basket of claim 6 wherein the actuation means is a cable containing a shape memory alloy.

8. The medical retrieval basket of claim 6 further including a substantially cylindrical tip at the distal end of said cage.

9. The medical retrieval basket of claim 6 wherein said flexible elements are in an approximately helical configuration.

10. The medical retrieval basket of claim 6 wherein said flexible elements are metallic with the materials being selected from a group consisting of stainless steels and other shape memory alloys.