U.S. patent application number 10/455145 was filed with the patent office on 2004-02-19 for aneurysm stent.
Invention is credited to Fulton, Michael, Thramann, Jeffrey.
Application Number | 20040034386 10/455145 |
Document ID | / |
Family ID | 31720736 |
Filed Date | 2004-02-19 |
United States Patent
Application |
20040034386 |
Kind Code |
A1 |
Fulton, Michael ; et
al. |
February 19, 2004 |
Aneurysm stent
Abstract
The present invention relates to an aneurysm stent having a base
and connector. The base has a vessel facing side and an aneurysm
facing side, and is shaped to cover an aneurysm sufficiently. The
connector is coupled to the aneurysm facing side of the base such
that when deployed the connector is adapted to extend partially
into the aneurysm to anchor the base about the aneurysm and inhibit
flow into the aneurysm.
Inventors: |
Fulton, Michael; (Superior,
CO) ; Thramann, Jeffrey; (Longmont, CO) |
Correspondence
Address: |
Brian P. Kinnear
Holland & Hart
Suite 3200
555 17th Street
Denver
CO
80202
US
|
Family ID: |
31720736 |
Appl. No.: |
10/455145 |
Filed: |
June 4, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60404422 |
Aug 19, 2002 |
|
|
|
Current U.S.
Class: |
606/200 |
Current CPC
Class: |
A61F 2002/30329
20130101; A61F 2002/91558 20130101; A61F 2002/91541 20130101; A61F
2002/91575 20130101; A61F 2250/001 20130101; A61F 2/91 20130101;
A61F 2002/9665 20130101; A61F 2/915 20130101; A61B 17/12022
20130101; A61F 2/852 20130101; A61F 2/95 20130101; A61F 2002/91591
20130101; A61F 2002/30599 20130101; A61F 2002/91508 20130101; A61B
17/12113 20130101; A61F 2002/30545 20130101; A61B 17/12136
20130101; A61F 2230/0095 20130101; A61B 2017/12068 20130101; A61F
2002/91533 20130101; A61F 2002/826 20130101; A61F 2002/828
20130101; A61F 2002/91525 20130101; A61B 2017/00867 20130101; A61F
2220/0025 20130101; A61F 2250/0071 20130101; A61F 2/958 20130101;
A61B 17/12172 20130101; A61B 2017/1205 20130101; A61F 2250/0063
20130101 |
Class at
Publication: |
606/200 |
International
Class: |
A61M 029/00 |
Claims
We claim:
1. An apparatus to inhibit flow to an aneurysm, comprising: a base
having a vessel facing side and an aneurysm facing side; the base
comprising a shape sufficient to cover an aneurysm; a connector;
and the connector coupled to the aneurysm facing side, wherein the
connector is adapted to anchor the base about the aneurysm to
inhibit flow into the aneurysm.
2. The apparatus according to claim 1, wherein the connector is a
coil adapted to pack in the aneurysm.
3. The apparatus according to claim 2, wherein the connector is
adapted to couple to at least one of the group consisting of: GDCs,
balloons, liners, polymers, and clotting agents.
4. The apparatus according to claim 1, wherein: the base comprises
an edge; and the connector has at least a first prong, such that
the edge and at least the first prong form a clamp that grips the
vessel wall to seat the base about the aneurysm.
5. The apparatus according to claim 1, wherein: the base comprises
graft material.
6. The apparatus according to claim 1, wherein: the base comprises
self-expanding material such that the base can be delivered in a
small package and expands on deployment to cover the aneurysm.
7. The apparatus according to claim 6, wherein the base also
comprises graft material.
8. The apparatus according to claim 1, wherein the connector
comprises at least one coil adapted to engage GDCs packed in the
aneurysm.
9. The apparatus according to claim 8, wherein the at least one
coil is made of at least a first shaped memory alloy.
10. The apparatus according to claim 9, wherein the at least one
coil is deformed such that on thermal treatment the at least one
coil engages GDCs and provides a force tending to seat the base
about the aneurysm.
11. The apparatus according to claim 1, wherein the base is at
least one of a triangular shape, a circular shape, a conical shape,
a spherical shape, an elliptical shape, a rectangular shape, and an
irregular shape.
12. The apparatus according to claim 1, wherein the base resides
completely in the vessel.
13. The apparatus according to claim 1, wherein the aneurysm facing
side is coated with an adhesive.
14. The apparatus according to claim 1, wherein the connector
comprises a post to be anchored in an occlusion in the
aneurysm.
15. The apparatus according to claim 1, wherein the connector
comprises at least one prong extending along an interior wall of
the aneurysm, the at least one prong adapted to be held in place by
at least one of a balloon or liner inserted in the aneurysm.
16. The apparatus according to claim 1, wherein the base comprises
at least one base coil arranged to expand on deployment.
17. The apparatus according to claim 16, wherein the at least one
base coil expands on activation.
18. The apparatus according to claim 16, wherein the at least one
base coil is arranged in the shape of a spiral.
19. The apparatus according to claim 16, wherein the at least one
base coil comprises a shaped memory alloy that is activated on
thermal manipulation.
20. The apparatus according to claim 1, wherein the vessel facing
side is coated with a material to stimulate cell growth and
encourage formation of a pseudointima.
21. The apparatus according to claim 1, wherein the connector is a
tightly wound coil of material that expands to a corkscrew shape to
anchor the stent.
22. The apparatus according to claim 1, wherein the connector is a
plurality of rings that expand to anchor the stent.
23. The apparatus according to claim 22, wherein the plurality of
cross-linked rings are orthogonal.
24. An aneurysm stent, comprising: a base; at least one connector
coupled to the base; the at least one connector adapted to be
inserted into an aneurysm packed with GDCs and, upon insertion, to
curl and pack into the aneurysm.
25. The aneurysm stent according to claim 24, wherein: the at least
one connector is coupled to a geometric center of the base.
26. The aneurysm stent according to claim 24, wherein: the at least
one connector is at least two connectors, each connector extending
in the aneurysm.
27. The aneurysm stent according to claim 26, wherein: the at least
two connectors are coupled to the base in a symmetrical manner.
28. The aneurysm stent according to claim 24, wherein the at least
one connector is made of a first shaped memory alloy.
29. The aneurysm stent according to claim 28, wherein the base is
made of a second shaped memory alloy.
30. The aneurysm stent according to claim 29, wherein the first
shaped memory alloy and the second shaped memory alloy are the
same.
31. The aneurysm stent according to claim 30, wherein the first
shaped memory alloy and the second shaped memory alloy are
nitinol.
32. The aneurysm stent according to claim 24, wherein the base has
a vessel side and an aneurysm side, the vessel side comprises a
layer of biocompatible material that promotes permanent fixation of
the stent
33. The aneurysm stent according to claim 32, wherein the
biocompatible material is a graft coated with a material to
stimulate cell growth and encourage formation of a
pseudointima.
34. The aneurysm stent according to claim 32, wherein the aneurysm
side has a layer of adhesive.
35. An apparatus to inhibit flow to an aneurysm, comprising: a base
having a vessel facing side and an aneurysm facing side; the base
comprising a shape sufficient to cover an aneurysm; and means for
anchoring the base about the aneurysm to inhibit flow into the
aneurysm.
36. The apparatus according to claim 35, wherein the means for
anchoring comprises: at least one of a coil, a post, a prong, and a
clamp.
37. A method for obstructing the flow of blood through the neck of
an aneurysm, the method comprising the steps of: passing a catheter
to the site of an aneurysm; inserting an anchor into the aneurysm;
deploying an aneurysm base to block the neck of the aneurysm; and
anchoring the aneurysm base about the neck of the aneurysm using
the anchor to inhibit the flow of blood in the aneurysm.
38. The method according to claim 37, further comprising the step
of: packing material in the aneurysm to form an occlusion.
39. The method according to claim 38, wherein the anchoring step
includes engaging the anchor with the packed material.
40. The method according to claim 38, wherein the anchoring step
further includes the step of: providing a seating force to assist
in seating the aneurysm base about the neck of the aneurysm.
41. The method according to claim 37, further comprising the steps
of: providing an adhesive coating on the aneurysm base; and
adhering the aneurysm base to the vessel during deployment.
42. An aneurysm stent, comprising: a base; at least one connector
coupled to the base; the at least one connector adapted to be
inserted into an aneurysm and, upon insertion, to anchor the base
about a neck of the aneurysm.
43. The aneurysm stent according to claim 42, wherein the at least
one connector comprises: at least one tightly wound coil that
extends from the base into the aneurysm; the at least one tightly
wound coil expands after insertion to pack the aneurysm and anchor
the stent.
44. The aneurysm stent according to claim 43, wherein the at least
one tightly wound coil expands into a corkscrew shape.
45. The aneurysm stent according to claim 42, wherein the at least
one connector comprises at least one of a plurality of coils, a
plurality of prongs, and a plurality of posts.
46. The aneurysm stent according to claim 45, wherein the plurality
of cross-linked coils are orthogonal.
Description
[0001] The present invention claims the benefit of U.S. Provisional
Application Serial No. 60/404,422, filed Aug. 19, 2002, titled
CEREBRAL ANEURYSM COIL STENT, incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to the surgical repair of
aneurysms and, more particularly, to a patch that provides a seal
between the arterial wall and a neck of the aneurysm to inhibit
flow in the aneurysm.
BACKGROUND OF THE INVENTION
[0003] An aneurysm is a blood-filled dilation of a blood vessel.
Major concerns with aneurysms revolve around rupturing of the
arterial wall causing internal bleeding and clots breaking away
from the aneurysm causing strokes.
[0004] There exist two generally approved methods of treating
aneurysms. The first method of treatment includes surgical
treatment. The second method of treatment includes endovascular
treatment. Surgical removal of the aneurysm is sometimes not
possible, leaving endovascular treatment as the only available
option. Even when not the only option, endovascular treatment often
is preferred because of the reduced risks and complications.
[0005] Conventionally, endovascular treatment of an aneurysm
involves "packing" the aneurysm such that an endovascular occlusion
is formed. Packing the aneurysm with coils, such as Guglielmi
Detachable Coils (or GDCs), helps form an occlusion. While using
GDCs is conventional, the aneurysm can be packed with numerous
devices, such as, for example, other types of coils, balloons,
glues, polymers, clotting agents, liners, or the like.
[0006] Endovascular treatment, while considered less risky than
surgical treatment, has drawbacks. One drawback of endovascular
treatment of the aneurysm includes the potential to over pack the
aneurysm. Over packing the aneurysm can cause the material to enter
the parent blood vessel, potentially inhibiting blood flow or
generate undesirable pressure in the aneurysm. Also, some aneurysms
have a wide connection to the blood vessel, a.k.a. wide neck
aneurysms. Wide neck aneurysms have the additional risk that the
occluded material will break free of the aneurysm and enter the
parent blood vessel, potentially causing blockage of the parent
blood vessel. Finally, clotting agents and polymers used to form
occlusions in the aneurysm can seep to the parent blood vessel
causing complications. Balloons and liners are intuitively pleasing
as a solution, but have the potential for an inexact fit causing
complications. For example, a balloon may be over inflated causing
unwanted pressure or under inflated causing seepage in the
aneurysm.
[0007] While the packing methods described above inhibit blood flow
to the aneurysm, the aneurysm neck typically is open to the parent
blood vessel. Thus, blood continues to flow to the aneurysm. To
reduce the blood flow, several devices have been developed to cover
the neck area of the aneurysm.
[0008] U.S. Pat. No. 6,454,780, issued Sep. 24, 2002, to Wallace,
titled Aneurysm Neck Obstruction Device, shows a device designed to
cover or block the neck of the aneurysm. FIG. 1 shows the Wallace
device 10 in some detail. The device 10 is placed inside aneurysm
50 using a catheter 46 and deployment tool 44. When inside the
aneurysm 50, device 10 has walls 12 that expand or unfold to
contact the inside of the aneurysm 50 and block neck 51. But the
device resides internal to aneurysm 50 allowing blood flow shown by
arrow A in the parent vessel 52 to push up against the walls 12.
The upward pressure of the blood vessel on the wall 12 may allow
blood from the parent vessel to seep in aneurysm 50. Also, because
the wall is internal to the aneurysm 50, the neck 12 has the
potential to expand. Other types of internal devices include liners
and other neck bridges.
[0009] Devices to block the neck of the aneurysm external to the
aneurysm exist also. These devices use the pressure of the blood
vessel to help seat the block against the parent vessel wall and
shield the neck from the blood vessel. One such device is shown in
U.S. Pat. No. 6,309,367, issued Oct. 30, 2001, to Boock, titled
Aneurysm Shield. The Boock device is shown in FIG. 2. The Boock
device 30 has a cylindrical shaft 32 that covers the neck 37 of the
aneurysm 38 and is anchored by anchor rings 34 and 36. While device
30 resides external to the aneurysm it has multiple parts that
could break free or deteriorate that reside in the parent vessel.
While the Boock device 30 seemingly works for its intended purpose
in theory, its relatively large size and surface area makes its
impractical to actually use. In the brain, for example, multiple
blood vessels may branch off from the location of an aneurysm.
Attempting to use the Boock device would block blood flow to one or
more of the branch vessels as well as the aneurysm, which makes the
Boock device useful in only limited situations, if any.
[0010] Thus, it would be desirous to develop and improve internal
and external aneurysm stents.
SUMMARY OF THE INVENTION
[0011] To attain the advantages and in accordance with the purpose
of the invention, as embodied and broadly described herein,
apparatuses to inhibit the flow of blood to an aneurysm comprise a
base and connector. The base has a vessel facing side and an
aneurysm facing side, and is shaped to cover an aneurysm
sufficiently. The connector is coupled to the aneurysm facing side
of the base such that when deployed the connector is adapted to
extend partially into the aneurysm to anchor the base about the
aneurysm and inhibit flow into the aneurysm.
[0012] The foregoing and other features, utilities and advantages
of the invention will be apparent from the following more
particular description of a preferred embodiment of the invention
as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0013] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate embodiments of
the present invention, and together with the description, serve to
explain the principles thereof. Like items in the drawings are
referred to using the same numerical reference.
[0014] FIG. 1 shows a prior art aneurysm device;
[0015] FIG. 2 shows a prior art aneurysm device;
[0016] FIG. 3 shows a perspective view of an aneurysm stent
deployed in a blood vessel illustrative of the present
invention;
[0017] FIG. 4 shows a cross section of a blood vessel with an
aneurysm prior to deployment of the aneurysm stent illustrated in
FIG. 3;
[0018] FIG. 5 shows a cross section of the aneurysm stent just
prior to deployment;
[0019] FIG. 6 shows a cross section of the aneurysm stent mostly
deployed about the aneurysm;
[0020] FIG. 7 shows a cross section of the aneurysm stent
deployed;
[0021] FIG. 8 shows a cross section of a portion of a stent
consistent with the present invention;
[0022] FIGS. 9A and 9B show a stent consistent with the present
invention; and
[0023] FIGS. 10A and 10B show a cross-section of a stent consistent
with the present invention.
DETAILED DESCRIPTION
[0024] Some embodiments of the present invention are described with
reference to FIGS. 3 to 10B. FIG. 3 shows an aneurysm stent 300
consistent with an embodiment of the present invention deployed.
Stent 300 is deployed in a parent blood vessel 302, which is shown
as an artery but could be a vein a capillary, or the like, about
aneurysm 304. A blood flow path from vessel 302 to aneurysm 304 is
provided by an aneurysm neck 306. Neck 306 is shown as a narrow
neck, but could be a wide neck. Aneurysm 304 is shown packed with
conventional GDCs 308. While shown as packed with conventional
coils, aneurysm 304 could be packed with any type of packing agent,
such as, for example, other types of coils, balloons, glues,
polymers, clotting agents, liners, or the like. In fact, aneurysm
304 does not need to be packed at all as stent 300 blocks blood
flow to aneurysm 304. The attachment of stent 300 to cover neck 306
will depend, in part, on the type of material used to pack aneurysm
304, if any.
[0025] With reference to FIG. 3, which illustrates aneurysm 304
packed with conventional GDCs 308, stent 300 includes a base 310, a
base connection point 312, and a connector 314. Base 310 has
opposed sides, a vessel side and a wall side (not specifically
labeled). The vessel side can be covered with a graft material or
other biocompatible material. The vessel side may be coated with a
material to stimulate cell growth and encourage formation of a
pseudointima. The wall side could be covered with an adhesive to
assist in seating stent 300 about neck 306 by forming a seal
between base 310 and vessel 302. Base connection point 312 couples
base 310 to connector 314. Base connection point 312 does not need
to exist as a separate component, but is identified for convenience
to distinguish between base 310 and connector 314. Base connection
point 312 could, as a matter of design choice, be a fitting to
connect base 310 and connector 314 if desired. Connector 314 can be
a conventional coil material attached to base 312 that extends to
GDCs 308. When deployed, connector 314 assumes its coiled shape and
engages GDCs 308 to assist in keeping stent 300 seated about neck
306. Connector 314 could physically curl around or hook into GDCs
308 for anchoring, but connector 314 could simply pack in aneurysm
304 similar to a conventional GDC. Connector 314 could simply
anchor stent 300 in place, but could also contract and pull base
310 snug against vessel 302 to firmly seat base 310 about aneurysm
neck 306 further inhibiting blood flow to aneurysm 304. While only
one base connection point 312 and one connector 314 is shown in
FIG. 3, multiple connections and connectors are possible. Also, the
connections do not necessarily have to be in the center of the
stent, but could be offset. It is believed greater stability will
be obtained by symmetrical placement of connectors and connection
points, but asymmetrical placement is possible. Multiple connectors
could be attached to a single connection point as well.
[0026] Referring now to FIGS. 4-7, a method of deploying the stent
300 will be described. Referring first to FIG. 4, parent vessel 302
is shown with aneurysm 304 and neck 306 existing off the main body
of vessel 302. Unlike FIG. 3, a second vessel 402 resides about
neck 306 forming a junction 404. While the present invention will
be explained in connection with deploying stent 300 about junction
404, stent 300 could be similarly deployed at locations with more
or less junctions. First, aneurysm 304 is packed using, for
example, conventional GDCs 308 in a conventional manner. Without
going in much detail, GDCs 308 are placed by first directing a
catheter 406 to the site of aneurysm 304. GDCs 308 are passed
through catheter 406 and packed in aneurysm 304 in a conventional
manner. Once GDCs 308 are placed, stent 300 is passed through the
same or a different catheter 406 using a guide wire 502 (FIG. 5).
Stent 300 includes base 310 and connector 314. As can be seen, base
310 is compacted to pass through catheter 406. Also, connector 314
enters the packed GDCs 308.
[0027] Referring now to FIG. 5, stent 300 has exited catheter 406
and guide wire 502 can be seen attached to stent 300. Base 310 is
approaching neck 306 and connector 314 has extended in GDCs 308
packed in aneurysm 304. As shown, base 310 can be made of a
self-expanding material that begins expanding on exiting catheter
406. Alternatively, base 310 can be made of a material that
requires activation or other manipulation to expand.
[0028] Referring now to FIG. 6, stent 300 is shown in the
appropriate position and guide wire 502 has been withdrawn. Base
310 has expanded sufficiently to mostly block neck 306 and
connector 314 has begun curling, packing, embedding or otherwise
anchoring in aneurysm. For example, connector 314 can be placed
about GDCs 308 as conventional packing material, connector 314 can
curl and engage GDCs 308, or the like. While one connector 314 is
shown, it would be possible to have two of more connectors 314. As
described in more detail below, a number of other devices and
techniques can be used to anchor stent 300 about the neck.
[0029] Referring now to FIG. 7, stent 300 is shown with base 310
and connector coils 314 fully deployed. In this case, base 310 is
flush with the wall of vessel 302, wraps around junction 404 and is
flush with the wall of vessel 402. Connectors 314 are engaged with
GDCs 308 and, optionally, connectors 314 contract in a manner that
pulls base 310 in toward GDCs 308 providing a snug seating between
base 310 and vessel 302.
[0030] The stent 300 could be made of many materials. Some material
includes conventional graft material. Alternatively, stent 300
could be made of one or more shaped memory alloys (SMAs) or a
combination of graft material and SMAs. SMAs are a group of
materials that demonstrate an ability to return to some previously
defined shape or size when subjected to the appropriate thermal
procedure. Generally, these materials can be plastically deformed
and, upon exposure to thermal manipulation, will return to the
pre-deformation shape. Some SMA material is considered to be
two-way shaped memory alloys because they will return to the
deformed shape upon proper thermal activation. SMAs include Ag--Cd
alloys, Cu--Al--Ni alloys, Cu--Sn alloys, Cu--Zn alloys, Cu--Zn--Si
alloys, Cu--Zn--Sn alloys, Cu--Zn--Al alloys, In--Ti alloys, Ni--Al
alloys, Ni--Ti alloys, Fe--Pt alloys, Mn--Cu alloys, Fe--Mn--Si
alloys, and the like. As shown by FIGS. 4-7, SMAs would work well
for stent 300 because, for example, connectors 314 could be shaped
with a predefined curl that will engage GDCs 308. The SMA could be
deformed at a predefined temperature to a straight, or
substantially straight, shape to allow for connectors 314 to
penetrate packed GDCs 308 in aneurysm 302. Thermal manipulation
would cause connector coils 314 to assume the original curled shape
that will anchor stent 300 about aneurysm 302 and may provide a
force tending to pull base 310 in towards aneurysm 302 further
seating stent 300 about aneurysm 302. Similarly, base 310 could be
made of SMA. In this case, base 310 could be originally shaped to
approximate the shape of the vessel(s) around aneurysm neck 304 to
allow for as close a fit as possible. This would also allow use of
stent 300 in areas having many vessels branching around the
aneurysm.
[0031] As shown in FIGS. 3-7, base 310 is shown having a circular
or semicircular shape. In particular, FIG. 3 illustrates base 310
as a coil of material that expands on deployment. The shape of base
310, however, is largely a function of material, design choice, and
the aneurysm location. Thus, stent 300 could take many shapes
including triangular, rectangular, square, elliptical, conical,
spherical, circular, cylindrical, or the like
[0032] The present invention has been described with the aneurysm
packed with conventional GDC coils, as described above, the
aneurysm could be packed with alternative material. For example, if
the aneurysm was packed with a polymer or clotting agent, the
connector or anchor could be a simple post connected to the stent
and embedded in the occlusion. Base 310 connected to the post would
be held in place by the occlusion. Further seating force could be
supplied by using a material that contracts on activation, such as
SMAs. If the aneurysm was packed with a liner or balloon, a
connection post could be provided on the balloon or liner to allow
attaching the stent to the balloon or liner. For example, a balloon
inserted in aneurysm 302 could have a flanged lower post (similar
to some helium balloons) that connector coil 314 could wrap around.
In this case, if, for example, connector coil 314 was made out of
SMAs, thermal activation could cause coil 314 to tighten around the
post attached to the balloon and contract. The contraction would be
resisted by the flange on the post tending to pull base 310 in
towards aneurysm 302 to assist in seating base 310 about aneurysm
302. Alternatively to a post, the stent could have prongs that
extend along the inside walls of the aneurysm such that the
expanded balloon or liner would press the prongs against the wall
of the aneurysm and seat the stent. Referring to FIG. 8, base 310
could be designed with a clamp 802 around an edge 804 of base 310.
As shown, clamp 802 could have opposed surfaces 806 such that when
deployed, surfaces 806 move together and grip vessel 302 at neck
306. A ridge 808 could be provided to assist in the grip. Clamp 802
would be particularly useful if aneurysm 304 was not packed with
anything.
[0033] Referring to FIGS. 9A and 9B, another stent 900 consistent
with the present invention is shown. Stent 900 includes a base 910
and a connector 920. Un deployed, connector 920 is a tightly
wrapped coil of material. On deployment, connector 920 unwinds into
a bulbous or volumous area sufficiently to anchor the stent 900.
Generally, connector 920 would expand to completely fill aneurysm
space, but at a minimum the expansion should be sufficient to
prevent connector 920 from pulling out of the aneurysm. As can be
appreciated, stent 900 could be used to treat the aneurysm without
packing material. But if packing material were used to treat the
aneurysm, connector 920 would not need to expand as much.
[0034] FIGS. 10A and 10B show another stent 1000 consistent with
the present invention. FIG. 10A shows a front plan view of a stent
1000 that includes a base 1010 and expanded connectors 1020 and
1030. While stent 1000 is shown with two orthogonal rings as
connectors 1020 and 1030, more rings could be used. Further the
rings could be cross-linked or individual rings. FIG. 10B shows a
side plan view of stent 1000 also with expanded connectors 1020 and
1030. As can be seen, connectors 1020 and 1030, which are shown in
the deployed state, expand to form rings that act similar to the
corkscrew anchor above. Also, while shown as rings any shape is
possible, such as diamond, circular, square, triangular,
elliptical, helical, or the like.
[0035] While the invention has been particularly shown and
described with reference to a preferred embodiment thereof, it will
be understood by those skilled in the art that various other
changes in the form and details may be made without departing from
the spirit and scope of the invention.
* * * * *