Prosthesis (i.e. – artificial body members) – parts thereof – or ai – Arterial prosthesis – Stent structure
Reexamination Certificate
1998-11-10
2001-04-10
Milano, Michael J. (Department: 3738)
Prosthesis (i.e., artificial body members), parts thereof, or ai
Arterial prosthesis
Stent structure
C623S001220
Reexamination Certificate
active
06214042
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to devices for maintaining blood vessels or other body ducts in an open condition, and more particularly to a coil wire stent having selected flex/stiffness orientations.
Vascular medical treatment procedures are known to include, among other things, occluding a blood vessel by thrombogenic devices, and maintaining the blood vessels open by use of a stent. Stents typically used in the past have consisted of a stainless steel tube section which includes selectively positioned gaps or openings which enable the section to be expanded, for example, by a balloon catheter, after the section is positioned at the desired location in the blood vessel. The expansion of the tubular section may be likened in some aspect to the expansion of a molly bolt cartridge in which two ends are drawn together causing the center section to bow outwardly.
Problems with the above prior art stent, among other things, are that the length changes when the tubular section is expanded (the length shortened), and the length of the stent is limited since the longer is the length, the more difficult it is to deliver the stent to a target location in the blood vessel. That is, the stent, being rigid, does not navigate well in the blood vessel, especially around tight corners. Further, since the described stent cannot be very long, numerous stents must be used for a diffuse diseased blood vessel.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a vasculature stent which is easily deployable in a vasculature or other body passageway to maintain the passageway in an open condition.
It is also an object of the invention to provide such a stent which is simple and inexpensive to manufacture.
It is a further object of the invention to provide such a stent which has stiffness/flexibility characteristics which accommodate the deployability of the stent and maintainability of the vasculature or other body passageway in the desired open condition.
The above and other objects are realized in a specific illustrative embodiment of a vasculature stent adapted for disposition in a blood vessel or other body duct to maintain the vessel or duct walls apart to allow the flow of blood or other duct function. This embodiment includes an elongate resilient wire or tube formed into a coil, which may be threaded lengthwise into and through a catheter for ultimate discharge therefrom to a target location in the blood vessel or duct. When the wire is discharged from the catheter, it resumes the coil form to thereby hold the vessel or duct walls apart.
In accordance with one aspect of the invention, the coil wire includes cuts selectively located on the exterior of the wire to provide flexibility in the direction of greatest curvature of the wire, and stiffness in the direction of least curvature of the wire. This enables the wire to be flexible for uncoiling the wire into an elongate shape for introduction into a catheter, while also allowing the wire to remain stiff in the transverse direction of the coil so that it is not easily compacted in that direction thereby serving to better maintain the vessel or duct patency.
In accordance with another aspect of the invention, the stent is formed from a hollow wire or tube, with cuts or openings formed to allow dispersion there through of medication carried in the hollow of the wire. With this configuration, a stent carrying medication or a therapeutic agent may be deposited in a vessel or duct so that the medication or agent flows from the stent to the vessel or duct walls to treat the problem—e.g. anti-restenosis agent, thrombolytic agent, etc.
REFERENCES:
patent: 4994069 (1991-02-01), Ritchart et al.
patent: 5282823 (1994-02-01), Schwartz et al.
patent: 5437288 (1995-08-01), Schwartz et al.
patent: 5545208 (1996-08-01), Wolf et al.
patent: 5696518 (1997-12-01), Laerum
patent: 5707389 (1998-01-01), Louw et al.
patent: 5709874 (1998-01-01), Hanson et al.
patent: 5749919 (1998-05-01), Blanc
patent: 5797953 (1998-08-01), Tekulve
patent: 5814063 (1998-09-01), Freitag
patent: 5824053 (1998-10-01), Khosravi et al.
patent: 5851232 (1998-12-01), Lois
patent: 5900246 (1999-05-01), Lanbert
Jacobsen Stephen C.
Lippert John
Milano Michael J.
Precision Vascular Systems, Inc.
Thorpe North & Western LLP
LandOfFree
Micro-machined stent for vessels, body ducts and the like does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Micro-machined stent for vessels, body ducts and the like, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Micro-machined stent for vessels, body ducts and the like will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2447711