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US4990155A Expired / Lapsed US ⏱️ 0.0 years remaining

Surgical stent method and apparatus

Assignee: Individual
•
Filing: 1989-05-19
•
Granted: 1991-02-05
•
Expires: 2009-05-19
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Abstract

Abstract A method for preventing arterial restenosis after angioplasty and including the steps of providing from a plastic material filament a base coil of a substantially uniform given diameter, inducing in the base coil an elastic memory that provides an inherent tendency thereof to return to the given diameter after any distortion, forming from the base coil a coil stent with a substantially uniform predetermined diameter substantially less than the given diameter, releasably coupling the coil stent to an elongated delivery device adapted to pass through a blood carrying vessel, inserting the coil stent and delivery device into a vessel, and manipulating the delivery device within the vessel so as to position the coil stent at a desired location therein. After placement, the coil stent is decoupled from the delivery device which is removed from the vessel, and the elastic memory is allowed to expand the coil stent into contact with the inner walls of the vessel and to the diameter substantially greater than the predetermined diameter. The use of an inherently expandable plastic coil stent permits the effective prevention of restenosis in small arteries typically found in the area of the heart.

Inventors

  • 👤 Howard M. Wilkoff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 23:52
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/95; A61F2/82; A61F2/86; A61F2/88; A61F2/0095

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 178 words
A method for preventing arterial restenosis after angioplasty, comprising the steps of: winding a plastic material filament into a helical base coil having a cross-section of substantially uniform given diameter; said providing step comprising the step of inducing in said filament an elastic memory that provides an inherent tendency for said base coil to return to said given diameter after any distortion thereof; forming from said base coil a helical coil stent with a cross-section having a substantially uniform predetermined diameter substantially less than said given diameter; releasably coupling said coil stent to an elongated delivery device adapted to pass through a blood carrying vessel; inserting said coil stent and delivery device into a vessel; manipulating said delivery device within the vessel so as to position said coil stent at a desired location therein; decoupling said coil stent from said delivery device; removing said delivery device from the vessel; and allowing said elastic memory to expand said coil stent into contact with the inner walls of the vessel and to a diameter substantially greater than said predetermined diameter.
Claim 2
Independent Claim 178 words
A method for preventing arterial restenosis after angioplasty, comprising the steps of: winding a plastic material filament into a helical base coil having a cross-section of substantially uniform given diameter; said providing step comprising the step of inducing in said filament an elastic memory that provides an inherent tendency for said base coil to return to said given diameter after any distortion thereof; forming from said base coil a helical coil stent with a cross-section having a substantially uniform predetermined diameter substantially less than said given diameter; releasably coupling said coil stent to an elongated delivery device adapted to pass through a blood carrying vessel; inserting said coil stent and delivery device into a vessel; manipulating said delivery device within the vessel so as to position said coil stent at a desired location therein; decoupling said coil stent from said delivery device; removing said delivery device from the vessel; and allowing said elastic memory to expand said coil stent into contact with the inner walls of the vessel and to a diameter substantially greater than said predetermined diameter.
Claim 3
Dependent Claim 33 words
A method according to claim 1 wherein said forming step comprises winding said base coil on a mandrel so as to produce said coil stent with a temporary set at said predetermined diameter.
Claim 4
Dependent Claim 29 words
A method according to claim 2 wherein said inducing step comprises subjecting said base coil to electron beam radiation so as to cause cross linkage of the molecules therein.
Claim 5
Dependent Claim 41 words
A method according to claim 3 wherein said providing step comprises winding said filament on a mandrel, applying heat to said mandrel retained base coil -so- as to relieve substantially all strain therein, and removing said base coil from the mandrel.
Claim 6
Dependent Claim 36 words
A method according to claim 4 wherein said coupling step comprises inserting said coil stent into a compartment portion of said delivery device, and said decoupling step comprises ejecting said coil stent from said compartment portion.
Claim 7
Dependent Claim 20 words
A method according to claim 5 wherein said providing step comprises adding an x-ray opaque material to said plastic material.
Claim 8
Dependent Claim 19 words
A method according to claim 5 wherein said providing step comprises adding an anti-coagulate substance to said plastic material.
Claim 9
Dependent Claim 22 words
A method according to claim 5 wherein said plastic material is a high density polyethylene having a specific gravity greater than 0.95.
Claim 10
Dependent Claim 82 words
A method according to claim 1 wherein said providing step comprises winding said filament on a mandrel to form said base coil having said given diameter and a predetermined length, packaging said base coil in a sterile package, and removing said base coil from said package; and said forming step comprises winding a portion of said base coil on a mandrel so as to provide therefore said predetermined diameter, and detaching said portion from said base coil to provide said coil stent.
Claim 11
Dependent Claim 29 words
A method according to claim 9 wherein said inducing step comprises subjecting said base coil to electron beam radiation so as to cause cross linkage of the molecules therein.
Claim 12
Dependent Claim 41 words
A method according to claim 10 wherein said providing step comprises winding said filament on a mandrel, applying heat to said mandrel retained base coil so as to relieve substantially all strain therein, and removing said base coil from the mandrel.
Claim 13
Dependent Claim 30 words
A method according to claim 1 wherein said expansion of said coil stent to said diameter substantially greater than said predetermined diameter requires a time period greater than 15 seconds.
Claim 14
Dependent Claim 33 words
A method according to claim 12 wherein said forming step comprises winding said base coil on a mandrel so as to produce said coil stent with a temporary set at said predetermined diameter.
Claim 15
Dependent Claim 29 words
A method according to claim 13 wherein said inducing step comprises subjecting said base coil to electron beam radiation so as to cause cross linkage of the molecules therein.
Claim 16
Dependent Claim 41 words
A method according to claim 14 wherein said providing step comprises winding said filament on a mandrel, applying heat to said mandrel retained base coil so as to relieve substantially all strain therein, and removing said coil stent from the mandrel.
Claim 17
Dependent Claim 41 words
A method according to claim 12 wherein said providing step comprises winding said filament on a mandrel, applying heat to said mandrel retained base coil so as to relieve substantially all strain therein, and removing said coil stent from the mandrel.
Claim 18
Dependent Claim 29 words
A method according to claim 1 wherein said inducing step comprises subjecting said base coil to electron beam radiation so as to cause cross linkage of the molecules therein.
Claim 19
Dependent Claim 41 words
A method according to claim 1 wherein said providing step comprises winding said filament on a mandrel, applying heat to said mandrel retained base coil so as to relieve substantially all strain therein, and removing said base coil from the mandrel.
Claim 20
Dependent Claim 31 words
A method according to claim 1 wherein said inserting, manipulating, and removing steps are performed in an operating room; and said forming step is performed in the operating room prior thereto.
Claim 21
Dependent Claim 82 words
A method according to claim 19 wherein said providing step comprises winding said filament on a mandrel to form said base coil having said given diameter and a predetermined length, packaging said base coil in a sterile package, and removing said base coil from said package; and said forming step comprises winding a portion or said base coil on a mandrel so as to provide therefore said predetermined diameter, and detaching said portion from said base coil to provide said coil stent.
Claim 22
Dependent Claim 38 words
A method according to claim 5 wherein said delivery device comprises an elongated cable and said decoupling step comprises the step of activating said cable to apply a force that ejects said coil stent from said compartment portion.

References Cited (Backward Citations)

US3993057A Cited
US4553545A Cited
US4655771A Cited
US4655771B1 Cited
US4503569A Cited
US4649922A Cited
US4781683A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-02-04 1994-08-06 1995-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-02-04 1998-08-06 1999-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-02-04 2002-08-06 2003-02-05 $7700.00 Window Closed / Lapsed

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