Source: http://www.google.com/patents/US7179285?ie=ISO-8859-1&dq=5,941,947
Timestamp: 2014-11-26 14:25:12
Document Index: 37806133

Matched Legal Cases: ['art 5', 'art 5', 'arts 5', 'art 5', 'arts 19', 'arts 18', 'arts 19', 'arts 19']

Patent US7179285 - Stent - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA stent (1) formed into a generally or substantially tubular body and expandable radially outward from inside of the tubular body, wherein cells (6) are connected vertically and so arranged as to surround the central axis (C1) of the stent (1) and thereby to form annular units (4), the annular units...http://www.google.com/patents/US7179285?utm_source=gb-gplus-sharePatent US7179285 - StentAdvanced Patent SearchPublication numberUS7179285 B2Publication typeGrantApplication numberUS 10/257,407PCT numberPCT/JP2001/003368Publication dateFeb 20, 2007Filing dateApr 19, 2001Priority dateApr 20, 2000Fee statusPaidAlso published asEP1277489A1, EP1277489A4, EP1277489B1, US20030158596, WO2001080936A1Publication number10257407, 257407, PCT/2001/3368, PCT/JP/1/003368, PCT/JP/1/03368, PCT/JP/2001/003368, PCT/JP/2001/03368, PCT/JP1/003368, PCT/JP1/03368, PCT/JP1003368, PCT/JP103368, PCT/JP2001/003368, PCT/JP2001/03368, PCT/JP2001003368, PCT/JP200103368, US 7179285 B2, US 7179285B2, US-B2-7179285, US7179285 B2, US7179285B2InventorsTakeshi Ikeuchi, Kouji Mori, Hiroo Iwata, Kazuaki Mitsudou, Hiroaki Nomiyama, Yoshiharu Yoshikawa, Masatoshi WatanabeOriginal AssigneeKawasumi Laboratories, Inc., Kazuaki Mitsudou, Takeshi Ikeuchi, Kouji Mori, Hiroo IwataExport CitationBiBTeX, EndNote, RefManPatent Citations (4), Referenced by (3), Classifications (11), Legal Events (4) External Links: USPTO, USPTO Assignment, EspacenetStentUS 7179285 B2Abstract A stent (1) formed into a generally or substantially tubular body and expandable radially outward from inside of the tubular body, wherein cells (6) are connected vertically and so arranged as to surround the central axis (C1) of the stent (1) and thereby to form annular units (4), the annular units (4) are extended along the axis of the stent (1), adjacent annular units (4) are connected at least at one portion by a connecting part (5), each of the cells (6) has at least one bent portion, and the angle of the bent portion after expansion of the tubular body until the diameter becomes 2.5 mm is larger than 30�. The stent ensures a high flexibility and radial support force, enhances the blood vessel expandability, and suppresses the foreshortening phenomenon and the flare phenomenon.
What is claimed is: 1. A stent formed into a generally or substantially tubular body comprising:
said stent being expandable to at least a diameter of 2.5 mm when an angle formed between said first strut and said substantially straight line portion of the second strut is 30��140�.
said stent being expandable to at least a diameter of 2.5 mm when an angle formed between said substantially straight line portion of said first curved strut and the second substantially straight strut is 30��140�.
said stent being expandable to at least a diameter of 2.5 mm when an angle formed between said two struts is 30 ��140�.
TECHNICAL FIELD The present invention relates to improvement of a stent used to improve a narrowed portion caused in a living body such as a blood vessel and the like.
TECHNICAL BACKGROUND A stent is a tubular medical implement which is detained in the narrowed portion in question to ensure a required tubular region(space) by expanding the narrowed portion and the like when a tubular portion of a living body such as a blood vessel or other portions gets narrowed or clogged from obliteration. The stent is inserted into the body, with the diameter thereof small, and allowed to expand in the narrowed portion to make the diameter thereof large so that the tubular portion in question is expanded and kept in the expanded state.
DISCLOSURE OF THE INVENTION The present invention is achieved from the point of view described above, and according to the present invention, the following invention can be provided.
[1] A stent 1 (1A, 1B) formed into a generally or substantially tubular body with annular units composed of a plurality of cells and being expandable radially outward from inside of the tubular body: wherein the plurality of the cells 6 (6A, 6B) are connected vertically and so arranged as to surround the central axis C1 of the stent which forms the tubular body and thereby to construct annular units 4 (4A, 4B);
wherein each of the cells 6 (6A, 6B) has at least one or more bent portions 12 (12A, 12B), and is formed in such a manner that the angle θ of the bent portion after expansion of the tubular body until the diameter becomes at least 2.5 mm is equal to or larger than 30�.
[2] The stent 1 (1A, 1B) according to [1], wherein the ratio of the length 6L (6AL, 6BL) to the length 5L (5AL, 5BL) of the above-described connecting part in the axial direction of the stent is formed such that when the length 6L (6AL, 6BL) of the above-described cells in the axial direction of the stent is assumed to be 100, then the length 5L (5AL, 5BL) is formed to be 50 to 100. [3] The stent 1 (1A, 1B) according to [1] or [2], wherein the connecting part 5 (5A, 5B) is constructed of at least 2 or more of bent portions 8 and an approximately or substantially straight line portion 7 continuing to the bent portions 8, and is connected to the cells 6 (6A, 6B) constructing adjacent different annular units 4 (4A, 4B) at the ends of the cells. [4] The stent 1 (1A) according to any one of [1] to [3], wherein the cell 6 (6A) is formed by connecting at least one or more approximately or substantially straight line portions 11 (11A) and curved line portions 13 (13A) through the bent portion 12 (12A). [5] The stent 1B according to any one of [1] to [3], wherein the cell 6B is formed by connecting an approximately or substantially straight line portion 11B having an acute angle X with respect to the center line C2 in the axial direction of each stent 1B to an approximately or substantially straight line portion 13B disposed almost horizontally to the center line C2 in the axial direction of the stent 1B through the above-described bent portion 12B. [6] The stent 1 (1A, 1B) according to any one of [1] to [5], wherein the connecting part 5 (5A, 5B) is constructed by connecting the bent portions 8 to the both sides of the central approximately or substantially straight line portion 7, and the end portions of the bent portion 8 are connected to the end portions of the cells 6 (6A, 6B) constructing respective adjacent different annular units 4 (4A, 4B) through the connection portions 9 (9A, 9B). [7] The stent 1 (1A, 1B) according to any one of [1] to [6], wherein the cell 6 (6A, 6B) is formed in a vertically asymmetrical manner to the center line C2, when divided vertically with the center line C2 in the axial direction of the stent. [8] The stent 1 (1A, 1B) according to any one of [1] to [7], wherein the connecting parts 5 (5A, 5B) are disposed at least one or more spaces apart in the radial direction of the stent 1 (1A, 1B). BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a plan view showing the stent of the present invention,
In the present invention, the cell 6 means one of constitutional units of patterns consisting the surface of the stent 1 and, as shown in FIG. 2, it includes all forms having at least one or more of bent portions 12, more concretely, bent portions 12 with acute angles X, and being constructed by connecting approximately or substantially straight line portions 11 and curved line portions 13 through the bent portion 12. In addition, when each of the cells 6 is divided vertically by the center line C2 in the axial direction of the stent, the cells 6 are formed in a vertically asymmetrical manner to the center line C2 so that the angle θ of the bent portion 12 after expansion of the tubular body is 30� or more as shown in FIG. 3, when, for example, the diameter φ of the tubular body, namely of the stent, is expanded to 2.5 mm.
When the approximately or substantially straight line portion 11, the bent portion 12 and the curved line portion 13 having small bent portions 14, all of which constitute the cell 6 (hereinafter also referred to as an approximately or substantially S-shaped portion) stand more perpendicularly with respect to the central axis C1 of the stent (or the tubular body) after expansion of the stent, the radial support force of the stent becomes larger. That is, as shown in FIG. 3, the closer to 180� the angle θ of the bent portion 12 after expansion reaches, the larger the radial support force of the stent becomes. Therefore, when designing the stent, it is preferable to design in such a manner that the angle θ of the bent portion 12 after expansion of the tubular body reaches at least 30� or more when the diameter φ of the tubular body becomes at least up to 2.5 mm, more preferably up to 3.0 mm.
In the axial direction of the stent, it is desirable to dispose 3 pieces or more, more preferably, 4 pieces to 8 pieces per 10 mm of the length in the axial direction of the stent, and when the diameter of the stent reaches the diameter on target for the stent expansion (spec diameter, for example, φ=3.0 mm or φ=4.0 mm), it is desirable, for example, to design the angle θ of the bent portion 12 after expansion to be at least 30� or more, preferably between 45� and 140�, more preferably between 45� and 120� as described previously.
It should be noted that, as for the diameter on target (targeted diameter), it is effective for the better radial support force of the stent to design the angle θ after expansion to be near 180�, for example, over 140�, as described above. However, it is not favorable because of the following problems such that the amount of deformation of the bent portion 12 becomes too large to maintain the strength of it in a favorable state, and the reduction in total length of the stent accompanied by the expansion (hereinafter referred to as foreshortening) becomes too large to make an easy positioning of the stent when detaining the stent.
For example, as shown in FIG. 2, the cells 6 are disposed or placed respectively asymmetrically with respect to the center line C2 in the axial direction of the stent through the connecting part 5. However, in the axial direction of the stent, they are disposed in the same direction and at the same height. In other words, the cells 6 in the axial direction of the stent are disposed so as to align and lie on top of one another if the cells 6 are shifted in the axial direction of the stent from the nth line (column) to the (n+1)th line (column), and the cells 6 in the same line (the same annular unit) are disposed in the same direction in the radial direction of the stent so as to align and lie on top of one another if they are slid vertically from their present positions to upward or downward in the same line. Incidentally, though approximately or substantially straight line portion 11 of each cell is in substantially horizontal (substantially in parallel) to the center line C2 respectively, it may be inclined at some angles in a range not to be less than 30� of the angle θ of the bent portion 12 after expansion.
As a material constructing the stents 1, 1A, 1B of the present invention, well-known materials itself can be used without any limitation and a metal pipe made of, for example, stainless steel such as SUS 316L and the like, a shape memory alloy such as Ti�Ni alloy, Cu�Al�Mn alloy and so on, Cu�Zn alloy, Ni�Al alloy, titan, titan alloy, tantalum, tantalum alloy, platinum, platinum alloy, tungsten and tungsten alloy is used to form the stent by a laser processing method or other processing method.
EXAMPLE 1 In the stent A (B) constructed by unit parts 19 of the construction consisting of approximately or substantially<shaped cells 17 and approximately or substantially S-shaped connecting parts 18, as shown in FIG. 10, in order to evaluate difference in radial support force due to the difference of the angle after expansion, the stent A (the number of arrangement: 8) and the stent B (the number of arrangement: 6) which are different in the number of arrangement of the unit parts 19 of the construction in the circumferential direction, are prepared as below, and respective radial support forces are evaluated and compared.
the number of the unit parts 19 to be arranged
strut width of the cell 17
1 θ angle after expansion by 3 mm
EXAMPLE 2 The stent 1 shown in FIG. 1 was prepared, and the radial support force was compared with conventional stents 201 (FIG. 11) and 241 (FIG. 12) and the flexibility was compared with the stent 201 to evaluate. The evaluation of the radial support force was carried out in the same manner as in the example 1, and the flexibility was evaluated by the 4 point bending test. The measurement result of the radial support force is shown in Table 2 and the measurement result of the flexibility is shown in Table 3.
11.7N � mm
17.1N � mm
EXAMPLE 3 The radial support force and the flexibility of the stent 1A shown in FIG. 6 (FIG. 7) and the stent 1B shown in FIG. 8 (FIG. 9) were measured and evaluated in the same manner as in Example 1 and Example 2. The measurement result of the radial support force is shown in Table 4 and the measurement result of the flexibility is shown in Table 5. As is clear from Tables, it is recognized that substantially the same results as in the stent 1 are obtained also as for the stent 1A and the stent 1B.
13.7N � mm
14.3N � mm
EXAMPLE 4 As for the stents 1, 1A, 1B in the present invention, the foreshortening values when the diameter φ of the stents were expanded to 3.0 mm were measured. The measurement was carried out in such a manner that each stent length (referred to as L1) before expansion and the corresponding stent length (referred to as L2) after expansion to 3.0 mmφ were measured and the reduction ratios of the total length were calculated with the following formula to have the foreshortening value. Foreshortening value=((L1−L2)/L1)�100
INDUSTRIAL UTILITY The stent of the present invention can ensure sufficiently both of high flexibility and a high radial support force and at the same time enhance the expandability of the blood vessel and suppress the foreshortening and the flare phenomenon, so that it can be preferably used as a stent to expand a narrowed portion of the blood vessel to ensure a necessary and important tubular region.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS5911754Jul 24, 1998Jun 15, 1999Uni-Cath Inc.Flexible stent with effective strut and connector patternsUS5922021 *Apr 25, 1997Jul 13, 1999Jang; G. DavidIntravascular stentWO1996026689A1Feb 28, 1996Sep 6, 1996Scimed Life Systems IncImproved longitudinally flexible expandable stentWO1999038457A1Feb 2, 1999Aug 5, 1999G David JangTubular stent consisting of horizontal expansion struts and contralaterally attached diagonal-connectors* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS8591571Aug 25, 2011Nov 26, 2013Japan Stent Technology Co., Ltd.Drug-eluting stentUS8641756Jun 8, 2012Feb 4, 2014Japan Stent Technology Co., Ltd.Sustained drug-releasing stentUS20110257727 *Apr 20, 2010Oct 20, 2011M.I.Tech Co., IncExpanding Vascular Stent* Cited by examinerClassifications U.S. Classification623/1.15International ClassificationA61F2/84, A61F2/06, A61F2/90Cooperative ClassificationA61F2002/91575, A61F2002/91533, A61F2002/91558, A61F2/915, A61F2/91European ClassificationA61F2/915, A61F2/91Legal EventsDateCodeEventDescriptionAug 3, 2012ASAssignmentFree format text: CHANGE OF ADDRESS;ASSIGNOR:KAWASUMI LABORATORIES, INC. (FORMER ADDRESS: 3-28-15 MINAMI-OHI, SHINAGAWA-KU, TOKYO, JAPAN);REEL/FRAME:028716/0851Owner name: KAWASUMI LABORATORIES, INC., JAPANEffective date: 20110105Jul 21, 2010FPAYFee paymentYear of fee payment: 4May 8, 2007CCCertificate of correctionMar 18, 2003ASAssignmentOwner name: IKEUCHI, TAKESHI, JAPANOwner name: IWATA, HIROO, JAPANOwner name: KAWASUMI LABORATORIES, INC., JAPANOwner name: MITSUDOU, KAZUAKI, JAPANOwner name: MORI, KOUJI, JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:IKEUCHI, TAKESHI;MORI, KOUJI;IWATA, HIROO;AND OTHERS;REEL/FRAME:013870/0466;SIGNING DATES FROM 20020927 TO 20021001RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google