Medical instrument for locating and removing occlusive objects

• US 4,046,150 A
• Filed: 07/17/1975
• Issued: 09/06/1977
• Est. Priority Date: 07/17/1975
• Status: Expired due to Term

• Current Assignee: Baxter International Inc.
• Original Assignee: American Hospital Supply Corp. (Baxter International Inc.)
• Inventors: Schwartz, Robert S., Pfister, Ronald R.
• Primary Examiner(s): Pace, Channing L.
• Application Number:
  US05/596,811
• Time in Patent Office: 782 Days
• Field of Search: 128/328, 128/350 R, 128/356
• US Class Current: 606/127
• CPC Class Codes: A61B 1/07 using light-conductive means, e.g. optical fibres
• CPC Class Codes: A61B 1/307 for the urinary organs, e.g. urethroscopes, cystoscopes
• CPC Class Codes: A61B 17/22012 in direct contact with, or very close to, the obstruction or concrement for removing obstructions in blood vessels by laser A61B18/245
• 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
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00

Abstract

An instrument particularly useful for locating and removing ureteral calculi and other occlusive objects from body passages. The instrument includes a flexible tube or sheath which slidably receives a tightly-twisted multi-stranded cable of a length greater than that of the tube, the cable having an integral cage portion at its distal end. That cage portion, which is normally collapsed and concealed within the distal end of the tube, may be extended beyond the tube to assume an expanded helical pear-shaped configuration for ensnaring and withdrawing ureteral stones and other passage-occluding bodies. The tightly wound strands of the cable are arranged in a circumferential pattern about an axial lumen which in one embodiment is useful for fluid drainage and injection and which in other embodiments accommodates conductors for transmitting light, images, and/or ultrasonic energy. The sheath or outer tube of the instrument is transparent, thereby permitting visual inspection of the spirally-wound cable slidably disposed therein. Suitable markings on the cable, visible through the transparent wall of the sheath, indicate the extent of insertion of the instrument during an operative procedure. The instrument also includes a handle for extending and retracting the cage, and suitable means for generating and transmitting light and ultrasonic waves.

Claims

1. An instrument for use in locating occlusive objects in body passages and removing the same therefrom, comprising a flexible transparent tube having proximal and distal ends and having a passage extending longitudinally therethrough;

a flexible cable extending through said passage;

said cable including a collapsible cage portion and being slidable within said passage between a first position wherein said cage portion is collapsed and retracted within said passage at the distal end of said tube and a second position wherein said cage portion is expanded, extended, and exposed beyond the tube'"'"'s distal end; and

handle means connected to said cable at the proximal end of said tube for selectively shifting said cage between its retracted and extended positions;

said cable having a lumen extending axially therethrough and communicating with said cage portion to provide a fluid pathway;

said cable being composed of filaments twisted together between said cage and said handle means to provide a series of coils visible through said transparent tube.

2. The instrument of claim 1 in which said cable is longer than said tube.

3. The instrument of claim 1 in which said filaments are formed of spring wire.

4. The instrument of claim 3 in which said wire filaments are wound in tight engagement to form a single layer extending circumferentially about said lumen.

5. The instrument of claim 1 in which said cage portion is generally pear-shaped in outline when the same is extended, expanded, and exposed, said pear-shaped cage portion having an enlarged end facing proximally and having its widest dimension on the proximal side of the exposed cage'"'"'s longitudinal mid point.

6. The instrument of claim 1 in which said cable is provided at selected points along the length thereof with surface markings visible through the transparent wall of said tube.

7. The instrument of claim 1 in which the internal diameter of said tube is substantially greater than the external diameter of said cable to provide an annular spacing therebetween.

8. An instrument for use in locating occlusive objects in body passages and removing the same therefrom, comprising a transparent flexible sheath having proximal and distal ends and having a passage extending longitudinally therethrough;

a flexible cable composed of a plurality of wires extending uninterruptedly from one end of said cable to the other;

said cable being slidably disposed in said passage of said sheath and having a length greater than said sheath;

said cable including an integral cage portion slidable between a first position wherein said cage portion is collapsed and retracted within said passage at the distal end of said sheath and a second position wherein said cage portion is expanded, extended, and exposed beyond the sheath'"'"'s distal end; and

handle means connected to said cable at the proximal end of said sheath for selectively shifting said cage portion between its first and second positions;

said wires being twisted tightly together between said handle means and said cage portion.

9. The instrument of claim 8 in which said cage portion is defined by said wires and has a pear-shaped configuration when expanded, extended, and exposed;

said pear-shaped cage portion having an enlarged end facing proximally and a reduced end extending distally, and having its widest dimension on the proximal side of the exposed cage'"'"'s longitudinal mid point.

10. The instrument of claim 9 in which a connecting member joins the wires at the distal end of said cage portion, said connecting member comprising a ring having a diameter no greater than the external diameter of said sheath.

11. The instrument of claim 10 in which said wires extend distally beyond said connecting member and are tightly twisted together to form an integral cable extension for a filiform tip.

12. The instrument of claim 8 in which said cable is provided at selected points along the length thereof with surface markings visible through said transparent sheath.

13. The instrument of claim 8 in which the internal diameter of said sheath is sufficiently greater than the external diameter of said cable to define an annular space therebetween.

14. The instrument of claim 8 in which said wires of said cable are wound into tight circumferential and longitudinal engagement to provide an annular arrangement of wires defining a lumen extending axially through said cable.