Assembly for placement of embolic coils using frictional placement

• US 5,312,415 A
• Filed: 09/22/1992
• Issued: 05/17/1994
• Est. Priority Date: 09/22/1992
• Status: Expired due to Fees

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Target Therapeutics, Inc. (Boston Scientific Corporation)
• Inventors: Palermo, Thomas J.
• Primary Examiner(s): Graysay, Tamara L.
• Application Number:
  US07/949,095
• Time in Patent Office: 602 Days
• Field of Search: 606/194, 606/191, 606/200, 606/159, 606/108, 606/151, 606/198, 604/159, 604/164, 128/772
• US Class Current: 606/108
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/1214 Coils or wires
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2230/0091 helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section

Abstract

This invention is a surgical instrument and specifically is a device for delivering embolic coils to a selected site within the vasculature of the human body via use of a catheter. Specifically, a pusher sheath within the catheter lumen pushes embolic coils mounted on a guidewire through the end of the catheter lumen. The catheter may have a constricted distal tip or other means of controlling the release of the embolic coils. Additionally (or alternatively), the guidewire may engage the embolic coils from their interior to allow precise placement of the coils.

Claims

1. A detachable pusher-coil assembly for use in occulding a selected site within a vessel comprising;

(a) a catheter sheath having a proximal end and a distal end, the distal end having a constricted distal tip, the constricted distal tip having an interior shape to frictionally engage but allow controlled passage of one or more separate embolic coils;

(b) a guidewire extending from the proximal end to the distal end of the catheter sheath and within the catheter sheath, said guidewire having a tip, said guidewire tip having an outer diameter which approximates an inner diameter of said one or more separate embolic coils, said guidewire tip for frictionally engaging an interior of said one or more embolic coils;

(c) a plurality of said separate embolic coils situated on said guidewire, each said separate embolic coil having an outer diameter sufficiently large to frictionally engage the constricted distal tip of the catheter sheath;

(d) a pusher sheath situated within the inside diameter of the catheter sheath proximal to the plurality of separate embolic coils and in which the guidewire passes therethrough, the pusher sheath having a diameter sufficient to be moved axially toward the distal end of the catheter sheath and thereby push said separate embolic coils through the distal end of the catheter sheath.

2. The assembly of claim 1, where each embolic coil includes helical coils.

3. The assembly of claim 2, where each embolic coil is of a straight configuration.

4. The assembly of claim 1 in which the guidewire tip is steerable.

5. The assembly of claim 1 in which each embolic coil is of a radio opaque material.

6. The assembly of claim 5 in which the radio opaque material is selected from platinum, tungsten, gold and their alloys.

7. A method for occluding a selected site within a vessel comprising the steps of:

(a) providing a pusher-coil assembly including

(i) a catheter sheath having a proximal end and a distal end, the distal end having a constricted distal tip, the constricted distal tip having an interior shape to frictionally engage but allow controlled passage of one or more separate embolic coils.

(ii) a guidewire extending from the proximal end to the distal end of the catheter sheath and within the catheter sheath, said guidewire having a tip, said guidewire tip having an outer diameter which approximates an inner diameter of said one or more separate embolic coils, said guidewire tip for frictionally engaging an interior of said one or more embolic coils;

(iii) a plurality of said separate embolic coils situated on said guidewire, each said separate embolic coil having an outer diameter sufficiently large to frictionally engage the constricted distal tip of the catheter sheath;

(iv) a pusher sheath situated within the inside diameter of the catheter sheath proximal to the plurality of separate embolic coils and in which the guidewire passes therethrough, the pusher sheath having a diameter sufficient to be moved axially toward the distal end of the catheter sheath and thereby push said separate embolic coils through the distal end of the catheter sheath;

(b) accessing the site with a distal end of the pusher-coil assembly;

(c) controlling passage of at least one of the separate embolic coils by;

(i) advancing the pusher sheath axially toward the distal end of the catheter sheath, engaging the at least one separate embolic coil with the constricted distal tip, and pushing said at least one separate embolic coil and the guidewire with its tip out from the constricted distal tip of the catheter sheath;

(ii) withdrawing the guidewire with its tip proximally of the at least one separate embolic coil and detaching the at least one separate embolic coil from the pusher-coil assembly;

(d) withdrawing the catheter assembly from the vessel, leaving the at least one detached separate embolic coil at the site.