U.S. patent application number 12/961471 was filed with the patent office on 2011-04-07 for devices and methods for treating vascular malformations.
Invention is credited to Martin s. Dieck, Son Gia, Ivan Sepetka.
Application Number | 20110082491 12/961471 |
Document ID | / |
Family ID | 23263261 |
Filed Date | 2011-04-07 |
United States Patent
Application |
20110082491 |
Kind Code |
A1 |
Sepetka; Ivan ; et
al. |
April 7, 2011 |
DEVICES AND METHODS FOR TREATING VASCULAR MALFORMATIONS
Abstract
The invention is also directed to a device for treating an
aneurysm which has a cover covering the neck of the aneurysm and a
lateral portion extending into the aneurysm. The invention is also
directed to a cover which is used to cover the neck of the aneurysm
thereby isolating the aneurysm from the parental vessel.
Inventors: |
Sepetka; Ivan; (Los Altos,
CA) ; Dieck; Martin s.; (Cupertino, CA) ; Gia;
Son; (San Jose, CA) |
Family ID: |
23263261 |
Appl. No.: |
12/961471 |
Filed: |
December 6, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10729432 |
Dec 4, 2003 |
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12961471 |
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09695637 |
Oct 24, 2000 |
6746468 |
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10729432 |
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09324359 |
Jun 2, 1999 |
6375668 |
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09695637 |
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Current U.S.
Class: |
606/194 |
Current CPC
Class: |
A61M 25/0074 20130101;
A61M 2025/1084 20130101; A61B 2018/00214 20130101; A61M 25/1002
20130101; A61B 17/1214 20130101; A61B 2017/00867 20130101; A61B
17/12022 20130101; A61M 29/02 20130101; A61B 2017/12068 20130101;
A61M 29/00 20130101; A61B 17/12109 20130101; A61B 2018/1495
20130101; A61B 2017/12095 20130101; A61B 17/12145 20130101; A61B
17/12168 20130101; A61B 2018/00416 20130101; A61M 2205/36 20130101;
A61B 17/12186 20130101; A61M 25/0068 20130101; A61B 18/1492
20130101; A61B 2017/1205 20130101; A61B 2017/12081 20130101; A61B
17/12172 20130101; A61M 25/0082 20130101; A61B 17/12136 20130101;
A61M 25/007 20130101; A61B 17/12118 20130101; A61B 17/12177
20130101; A61B 17/12113 20130101 |
Class at
Publication: |
606/194 |
International
Class: |
A61M 29/00 20060101
A61M029/00 |
Claims
1-58. (canceled)
59. A method of treating an aneurysm, comprising the steps of:
providing a device having a plurality of filaments extending from a
first hub, the plurality of filaments being movable from a
collapsed position to an expanded position, the filaments being
biased toward the expanded position; introducing the device into an
aneursym with the plurality of filaments in the collapsed position;
expanding the filaments after the introducing step so that the
filament occupy space in the aneurysm and form a mesh which
contacts the wall of the aneurysm; releasing the device so that the
device remains within the aneurysm with the mesh in contact with
the wall of the aneurysm.
60. The method of claim 59, wherein: the providing step is carried
out with the device having a second hub, the plurality of filaments
extending between the first and second hubs, the first and second
hubs moving toward one another when the plurality of filaments move
to the expanded position.
61. The method of claim 59, wherein: the expanding step is carried
out with the plurality of filaments expanding radially outward from
the first hub.
62. The method of claim 59, wherein: the expanding step is carried
out with the plurality of filaments forming a mesh which expanding
into contact with the aneurysm.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation in part of U.S.
patent application Ser. No. 09/324,359 filed Jun. 2, 1999 which is
hereby incorporated by reference for all purposes.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to treatment of abnormalities
in a patient's to vascular system. A specific use of the present
invention described below is for the treatment of cerebral
aneurysms although the various aspects of the invention described
below may also be useful in treating other abnormalities such as
arteriovenous malformations (AVM), hypervascular tumors, cavernous
carotid fistulas, fibroid tumors, and non-reversible sterilization
via fallopial occlusion.
[0003] Cerebral aneurysms are enlargements of the cerebral
vasculature which protrude like a balloon from the wall of a
cerebral artery. The cerebral aneurysm has a neck which leads to
the parental vessel and a body or "dome" which can vary in diameter
from 1-30 mm.
[0004] The wall of the aneurysm is often weak and can rupture,
leading to hemorrhage. Rupture of the aneurysm can kill the patient
or leave the patient with permanent or transitory mental and
physical deficits.
[0005] Aneurysms are often treated to prevent rupture, leading to
hemorrhage, or to prevent rebleeding of acutely ruptured aneurysms.
A conventional method of treating aneurysms is to fill the aneurysm
with coils. The coils are introduced into the aneurysm one at a
time through a delivery catheter until the aneurysm is filled. The
aneurysm eventually becomes a solid mass of coils and thrombus.
[0006] A problem with the conventional method of using coils to
fill aneurysms is that the aneurysm becomes a relatively solid mass
due to coils and thrombus contained therein. The mass of coil and
thrombus exerts pressure on adjacent areas of the brain which may
lead to other problems. Another problem with the conventional
method is that the coils must be delivered one at a time into the
aneurysm which increases the procedure time and risk to the
patient. For large aneurysms, up to twenty coils may be required to
fill the aneurysm.
[0007] It is an object of the invention to provide improved methods
and devices for treating aneurysms. These and other objects of the
invention will become evident from the description of the preferred
embodiments described below.
SUMMARY OF THE INVENTION
[0008] In a first aspect of the present invention, a method of
treating an aneurysm is provided. An expandable structure is
delivered through the vasculature in a collapsed position. Once the
expandable structure is at the desired location, such as within a
cerebral aneurysm, the expandable structure is expanded. The
structure and advantages of the expandable structure are described
below. The aneurysm wall is also reduced in size so that the
aneurysm does not need to be completely filled in the conventional
manner. The expandable shape is sized to be smaller than the
aneurysm to permit reducing the size of the aneurysm by at least
30% percent.
[0009] A preferred method of reducing the size of the aneurysm is
to heat the aneurysmal wall, preferably to a temperature of at
least 60.degree. and preferably 60-80.degree. C., which causes the
aneurysmal wall to shrink. The aneurysm may be heated in any
suitable manner and preferred methods are monopolar and bipolar RF,
laser, microwave, and simple electrical resistance heating. In a
preferred method, electrical energy is delivered to the expandable
device itself to generate heat. A fluid may be introduced into the
aneurysm to prevent clotting during heating and to provide thermal
and/or electrical conductance. When using RF heating, for example,
the fluid may be saline and more preferably hypertonic saline.
Although it is preferred to heat the aneurysmal wall to reduce the
size of the aneurysm, the aneurysm may also be reduced in size by
chemical action.
[0010] The expandable structure forms a matrix of filaments in the
expanded condition. The matrix preferably forms a woven or braided
structure, however the filaments may also be randomly oriented,
parallel, or non-intersection filaments. The matrix'may be flexible
filaments, such as platinum ribbon, extending randomly, radially or
helically within an expandable, permeable, mesh-like enclosure. The
material may also be an expandable material such as polymer,
nitinol, stainless steel, tungsten or tantalum and
alloys/composites thereof.
[0011] The expandable device preferably fills a volume of at least
10% of the aneurysm volume, more preferably at least 40% and most
preferably at least 60% of aneurysm volume. The expandable device
preferably has internal filaments within the volume to quickly form
a stable thrombus. An advantage of the expandable device is that a
three-dimensional structure forms without requiring separate
delivery of a cage and coils as described in International
Application WO 99/07293. In another aspect, the expandable device
has a deforming portion which plastically deforms when moving to
the expanded position. The deformable portion holds the flexible
filaments in the expanded position.
[0012] The aneurysm may be reduced in size until the aneurysmal
wall contacts the expandable structure so that the expandable
structure stipports and reinforces the aneurysmal wall. In a
particularly advantageous embodiment of the invention, the
expandable structure itself is used to transmit energy to heat the
aneurysmal wall which causes the aneurysmal wall to fuse to the
expandable structure, thereby reinforcing the aneurysmal wall and
preventing migration of the expandable structure into the parental
vessel.
[0013] In another aspect of the invention, the aneurysmal wall may
be reduced in size together with the expandable device. In a
preferred embodiment, the expandable structure is a soft mesh which
easily collapses when the aneurysmal wall is shrunk.
[0014] Various optional steps and structure may also be provided.
For example, a sealant may be delivered into the aneurysm to ensure
that the aneurysm is isolated from the parental artery. An
advantage of the present invention is that the sealant is held
within a matrix formed by the expandable device which holds the
sealant in the aneurysm.
[0015] The proximal portion of the expandable structure may be
insulated to protect the neck of the aneurysm. The insulation may
coat only the flexible filaments so that the structure is still
permeable to fluid. Alternatively, the insulation may be
impermeable to protect the neck from hot fluid slowly expelled into
the aneurysm or to isolate the aneurysm entirely from the parental
vessel.
[0016] The expandable device may have one or more expandable
sections. In an embodiment, the expandable device has two
expandable sections wherein energy is delivered to the dome with
one of the sections while the second section is insulated to
protect the neck.
[0017] The expandable device may have a locking mechanism for
locking the expandable device in the expanded position. The
expandable device is naturally biased toward the collapsed position
so that the operator may partially deploy the expandable device to
determine whether the device has the appropriate size. If the
device does not have the appropriate size, the device is collapsed
and removed and another device having the appropriate size is
introduced. The locking mechanism is then actuated when the user is
satisfied with the size of the device.
[0018] In still another aspect of the present invention, a catheter
has a cover which is positioned over the neck of the aneurysm to
isolate the aneurysm from the parental vessel. The aneurysm is then
reduced in size as explained above while the cover isolates the
aneurysm. The cover also protects the patient from hemorrhage by
isolating the aneurysm from the parental vessel. The cover may be
periodically moved to expel heated fluid into the parental vessel
when heating and shrinking the aneurysm.
[0019] In yet another aspect of the present invention, a coil is
used to cover the neck of the aneurysm to regulate the flow of hot
fluid out of the aneurysm and into the parental vessel. The pitch
of the coil can be varied by the operator during deployment to
allow faster or slower leakage of hot fluid out of the aneurysm and
into the parent artery during heating.
[0020] A catheter is also provided which has a low-impedance coil,
such as flat copper ribbon or other suitable material, disposed in
the catheter tip. Upon infusion of saline through the catheter and
passage of RF energy through the coil, the saline is heated and
conducts electrical energy to heat the fluid.
[0021] These and other aspects and advantages of the invention will
become evident from the following description, drawings and
claims.
[0022] Still another device for treating an aneurysm is provided
which has a cover which covers the neck of the aneurysm to isolate
the aneurysm from a parental vessel. The device also has a lateral
extension which is coupled to the cover and extends into the
aneurysm when the cover is positioned over the neck of the
aneurysm.
[0023] The cover is preferably a mesh and the lateral extension
preferably forms 1-8 loops. The cover is preferably a substantially
flat element which is positioned against a wall of the parental
vessel around the neck of the aneurysm. The cover preferably
extends no more than about 180 degrees around a longitudinal axis
of the device when expanded so that branch vessels are not occluded
by the cover. The extension is preferably expandable with one end
connected to the cover and the other end sliding relative to the
cover to permit the extension to expand and contract.
[0024] The present invention describes still another device for
treating an aneurysm which has the cover for covering the neck of
an aneurysm. The cover is mounted to an expandable element and is
covered by a retractable sheath. The sheath is preferably folded
over itself at the distal end so that the cover is exposed as the
sheath is pulled back over itself. The cover is preferably wrapped
around the expandable member without overlapping folds, flaps or
sections. The cover is preferably adhered to the parental vessel
wall in any suitable manner such as with an adhesive. The cover may
be a sheet of material or a metallic frame having impermeable layer
attached thereto.
[0025] Yet another device for treating an aneurysm is provided
which has a plurality of filaments extending between proximal and
distal hubs: The filaments preferably form a generally concave
surface which covers a neck of an aneurysm when positioned in the
aneurysm. The device may also have a concave side opposite the
convex side. The filaments form overlapping loops when viewed along
an axis through the hubs. The filaments are preferably in a
relatively straight configuration when advanced through the
delivery catheter to the aneurysm.
[0026] Still another device for treating an aneurysm has a
plurality of filaments, preferably 2-4 filaments, with the proximal
ends of the filaments being coupled together and the distal end of
the filaments being free. Each of the filaments preferably form a
coil in the expanded position. The coils may have a central axis
generally lying in the same plane.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a system for treating a patient's vascular
system.
[0028] FIG. 2 shows an expandable device in a collapsed
position.
[0029] FIG. 3 is a perspective view of the expandable device with
the mesh removed.
[0030] FIG. 4 is a cross-sectional view of the expandable
device.
[0031] FIG. 5 shows the expandable device in an aneurysm.
[0032] FIG. 6 shows the expandable device detached from the
delivery catheter.
[0033] FIG. 7 shows the expandable device of FIG. 6 with a sealant
introduced into a portion of the expandable, device.
[0034] FIG. 8 shows the sealant filling the aneurysm and the
expandable device.
[0035] FIG. 9 shows the expandable device having a proximal portion
which is relatively impermeable to the sealant so that the sealant
is retained in the aneurysm.
[0036] FIG. 10 shows the expandable device filled with an
expandable material such as random fibers or a coil.
[0037] FIG. 11 shows another expandable device which is deployed
with a balloon in a collapsed position.
[0038] FIG. 12 shows the expandable device of FIG. 11 in an
expanded position.
[0039] FIG. 13 shows the expandable device reduced in size and the
expandable device having a proximal portion which is insulated to
protect the neck of the aneurysm.
[0040] FIG. 14 shows the expandable device of FIG. 11 with simple
resistance heating used to shrink a portion of the aneurysm into
contact with the expandable device.
[0041] FIG. 15 shows the use of simple resistance heating to shrink
another portion of the aneurysm into contact with the expandable
device.
[0042] FIG. 16 shows a heating device.
[0043] FIG. 17 shows a heating device with the tip curved.
[0044] FIG. 18 shows the heating device used with the expandable
device of FIGS. 11-14.
[0045] FIG. 19 shows the aneurysm shrunk into contact with the
expandable device.
[0046] FIG. 20 shows the expandable device reduced in size during
shrinking of the aneurysm.
[0047] FIG. 21 shows another expandable device having a locking
mechanism for holding the device in the expanded position.
[0048] FIG. 22 shows the expandable device of FIG. 21 with the
device in the expanded position.
[0049] FIG. 23 shows the device of FIGS. 21 and 22 released from
the delivery catheter.
[0050] FIG. 24 shows a catheter having a cover for isolating an
aneurysm from the parental vessel.
[0051] FIG. 25 is a cross-section of the catheter of FIG. 21 along
line A-A.
[0052] FIG. 26 shows the catheter of FIG. 21 with the cover having
a curved shape.
[0053] FIG. 27 shows the catheter of FIG. 21 isolating an
aneurysm.
[0054] FIG. 28 shows the aneurysm reduced in size and a
thrombogenic material and sealant introduced into the aneurysm.
[0055] FIG. 29 shows only the thrombogenic material in the
aneurysm.
[0056] FIG. 30 shows another expandable device in a collapsed
position.
[0057] FIG. 31 shows the expandable device of FIG. 30 in an
expanded position.
[0058] FIG. 32 is an alternative embodiment of the device of FIGS.
30 and 31.
[0059] FIG. 33 is another alternative embodiment of the device of
FIGS. 30 and 31.
[0060] FIG. 34 shows a mesh structure for use with any of the
expandable devices described herein.
[0061] FIG. 35 shows a number of expandable device delivered to the
aneurysm.
[0062] FIG. 36 shows the aneurysm of FIG. 35 reduced in size.
[0063] FIG. 37 shows a coil for regulating flow between an aneurysm
and a parent vessel.
[0064] FIG. 38 shows the coil of FIG. 37 with the windings spaced
close together to further impede fluid flow between the aneurysm
and the parent vessel.
[0065] FIG. 39 shows another catheter for heating tissue.
[0066] FIG. 40 is a cross-sectional view of the distal end of the
catheter of FIG. 39.
[0067] FIG. 41 shows the tip of the catheter of FIGS. 39 and 40
with holes at the distal end of the tip.
[0068] FIG. 42 shows the tip of the catheter of FIGS. 39 and 40
with holes along the side of the tip.
[0069] FIG. 43 shows another device for treating an aneurysm.
[0070] FIG. 44 shows the device of FIG. 43 contained within a
catheter for delivery to the aneurysm.
[0071] FIG. 45 shows an extension of the device positioned in the
aneurysm.
[0072] FIG. 46 shows the device of FIGS. 43-45 deployed with a
cover over the neck of the aneurysm.
[0073] FIG. 47 shows another device for treating an aneurysm.
[0074] FIG. 48 shows the device of FIG. 47 partially deployed with
an expandable element:
[0075] FIG. 49 shows the device of FIG. 48 with the sheath full
retracted and the expandable element expanded to move the cover
over the neck of the aneurysm.
[0076] FIG. 50 shows the device of FIG. 47-49 fully deployed.
[0077] FIG. 51 shows an alternative cover for the device of FIGS.
47-49.
[0078] FIG. 52 shows yet another device for treating aneurysms in a
collapsed position.
[0079] FIG. 53 is a side view of the device of FIG. 52 in an
expanded condition.
[0080] FIG. 54 is a plan view of the device of FIG. 52 in an
expanded condition.
[0081] FIG. 55 shows a catheter delivering the device of FIGS.
52-54 to an aneurysm.
[0082] FIG. 56 shows the device of FIGS. 52-54 deployed in the
aneurysm.
[0083] FIG. 57 shows still another device for treating an
aneurysm.
[0084] FIG. 58 shows the device of FIG. 57 deployed within an
aneurysm.
[0085] FIG. 59 shows a plan view of the device of FIGS. 57 and
58.
[0086] FIG. 60 shows an alternative to the device of FIGS.
57-59.
[0087] FIG. 61 shows another alternative to the device of FIGS.
57-59.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0088] Referring to FIG. 1, a system 2 for introducing an
expandable device 4 into a cerebral aneurysm is shown. A first
catheter 6 extends through a penetration in the femoral artery and
up to the carotid artery. A second catheter 8 is advanced through
the first catheter 6 and into the cerebral vasculature to the site
of the aneurysm or other abnormality. A delivery catheter 10 is
then advanced through the second catheter 8. The catheter 10
delivers an expandable device 4 which partially fills the aneurysm
as will be described below. The system 2 also has an energy supply
12 for heating the aneurysm to shrink the aneurysm as will be
described below.
[0089] After the expandable device 4 has been delivered to the
aneurysm and expanded, the aneurysm is reduced in size as shown in
FIG. 6. The aneurysm may be shrunk partially toward the expandable
device 4, into engagement with the expandable device 4, or may even
be shrunk until the expandable device 4 is also reduced in size. An
advantage of shrinking the aneurysm is that the aneurysm does not
need to be completely filled with coils in the conventional manner.
The conventional method of filling the aneurysm with coils creates
a relatively solid mass in the aneurysm which can press against
adjacent structures leading to further problems. The expandable
device 4 is removably mounted to the end of a shaft 5 in the manner
described below so that the expandable device 4 may be released in
the aneurysm. The expandable device may be released with a
mechanical mechanism, a thermoadhesive bond, or an electrolytically
or chemically severable bond.
[0090] The aneurysm may be shrunk in any suitable manner and a
preferred method is to heat the aneurysmal wall. Shrinking of the
aneurysm may also be accomplished through chemical action. The
aneurysmal wall is preferably heated to a temperature of
60-80.degree. C. and preferably at least 70.degree. C. Depending
upon the size of the aneurysm, the aneurysmal wall is preferably
heated for at least 10 seconds and generally between 10 seconds and
5 minutes.
[0091] In the preferred system of FIG. 1, the energy supply 12
supplies RF energy to heat and shrink the aneurysm. The expandable
device 4 is preferably configured as a mono-polar RF electrode 14
and the energy supply 12 is preferably an RF generator. A suitable
second electrode (not shown) is placed in contact with the
patient's skin in the conventional manner. The aneurysm may, of
course, be heated with the energy supply being a hot fluid, laser,
microwave, bi-polar RF or a resistance heating device without
departing from the scope of the invention.
[0092] Referring to FIGS. 1 and 4, the catheter 8 has a lumen 16
coupled to a source of fluid 18 which is preferably a conductive
fluid such as saline and more preferably hypertonic saline. The
lumen 16 may also be coupled to a source of sealant 20 which may be
used to seal the aneurysm as described below. The sealant may be
any suitable sealant such as cyanoacrylates, ethylene
vinyl-alcohol, cellulose acetate polymers, fibrin glues and other
liquid-type tissue sealants. The sealants may also be bioperodable
and/or bio-absorbable. The lumen 16 is also coupled to a vacuum
source 22 for suctioning fluids and reducing the size of the
aneurysm. A source of contrast 24 is also provided for
visualization of the aneurysm, vasculature and device positions. A
valve 26 couples the lumen 16 to the various sources 18, 20, 22,
24. The delivery catheter 10 also has a lumen 28 which may be
coupled to the sources 18, 20, 22, 24 and discussion of use of the
lumen 16 is equally applicable for the lumen 28.
[0093] Referring to FIGS. 2, 3 and 5, the expandable device 4 has
first and second expanding sections 30, 32. Although it is
preferred to provide both the first and second expanding sections
30, 32, the expandable device 4 may include only one expanding
section or three or more expanding sections without departing from
the scope of the invention. The first section 30 acts as the
electrode 14 to deliver RF energy from the energy source 12 to the
aneurysm. The second section 32 is insulated and does not transmit
energy to the aneurysm so that the neck of the aneurysm is
protected. The second section 32 is preferably coated with PTFE,
polyamide, FED, or PFA to prevent RF energy transmission.
Protecting the neck of the aneurysm also protects peripheral
vessels adjacent the neck of the aneurysm.
[0094] The second expandable section 32 may be permeable to fluid
so that heated fluid in the aneurysm may be slowly expelled into
the parental vessel to dissipate heat. The second section 32 may
also have a fluid impermeable portion 36 adjacent the neck to
further protect the neck of the aneurysm as shown in FIG. 9. The
fluid impermeable portion 36 is preferably a flexible sheath 38
having a ring or annular shape. The ring shape may interrupted at a
radially inner portion 39 so that heated fluid may still be slowly
expelled into the parental vessel. Alternatively, the sheath 38 may
completely isolate the aneurysm from the parental vessel.
[0095] The first and second expandable sections 30, 32 have a
number of flexible filaments 40 which move from the collapsed
position of FIG. 2 to the expanded position of FIG. 5. The flexible
filaments 40 are preferably woven or braided to form a
substantially closed-form mesh structure 42 in the expanded
position. The filaments 40 and mesh 42 have the characteristics
described below and are graphically depicted in the drawings for
clarity. A preferred mesh structure 42 is also described with
reference to FIG. 34 below.
[0096] Referring again to FIGS. 2 and 3, the filaments 40 are
positioned over deformable elements 48 which hold the flexible
filaments 40 in the expanded position. Referring to FIG. 3, the
deformable elements 48 have columns 50 extending between collars
52, 53 at the ends. The deformable elements 48 are formed from
tubes which have four cut-out sections 54 to form the columns 50.
The collars 52 are then attached to the ends of the tube. The
columns 50 are bent outward slightly so that they will buckle
outwardly when compressed. As will be described in further detail
below, the deformable elements 48 are plastically deformed when
moving to the expanded position to hold the filaments 40 in the
expanded position. The columns 50 may also be designed with curved
or sinusoidal shaped sections to improve flexibility.
[0097] Referring to FIG. 4, the proximal and distal collars 52 are
threaded to engage a threaded tip 58 of a guidewire 60 for
manipulating the expandable device 4. Intermediate collars 62
provide only throughholes to hold and guide the expandable device 4
on the guidewire 60. When expanding the device 4, the guidewire 60
is pulled until the device 4 is trapped between the delivery
catheter 10 and the threaded tip 58. The guidewire 60 is then
rotated to engage the tip 58 with the distal threaded collar 52.
When the tip 58 is threaded into engagement with the distal collar
52, the guidewire 60 can be pulled to expand the device. When the
device 4 is partially expanded, the deformable elements 48 may
still be within their elastic range so that the expandable device 4
will recover the collapsed position when tension is released on the
guidewire 60. The operator may then check to see if the device 4
has the appropriate size and shape for the aneurysm before fully
deploying the device. If the operator determines that the device 4
is too small or too large, the device 4 is collapsed and removed
and another expandable device of appropriate size advanced to the
aneurysm.
[0098] When the operator is ready to deploy the device 4, the
operator pulls the guidew ire 60 so that the deformable elements 48
undergo plastic deformation and move to the expanded position. Even
if the device 4 is moved to the expanded position, the operator may
still retrieve the device by engaging the proximal collar 53 with
the threaded tip 58 and withdrawing the device into the second
catheter 8.
[0099] After the expandable device 4 has been moved to the expanded
position, the aneurysm is then preferably reduced in size. In a
preferred method, RF energy is delivered to the first expandable
section 30 through the guidewire 60 and a conductive fluid,
preferably hypertonic saline, is injected into the aneurysm through
the lumen 16 or lumen 28, FIG. 6 shows the aneurysm reduced in size
until the aneurysm engages the first section 30. The threaded tip
58 is then disengaged from the device 4 leaving the device 4 in the
shrunken aneurysm.
[0100] As an optional step, the sealant 64 from the source of
sealant 20 may also be introduced into the entire aneurysm (FIG. 8)
or into just the second section 32 (FIG. 7) to seal the aneurysm.
An advantage of the present invention over conventional methods is
that the sealant 64 is contained within the closed-form mesh
structure 42 to prevent escape of the sealant 64 into the parental
vessel. Referring to FIG. 9, a proximal portion 66 may be
impermeable to further isolate the aneurysm from the parental
vessel. A small amount of the sealant 64 may also be delivered to
completely isolate the aneurysm if necessary as shown at
dotted-line 68. The method of the present invention described above
may, of course, be practiced with any suitable structure other than
the structure of FIGS. 1-9 without departing from the scope of the
invention.
[0101] Referring to FIGS. 11-15, another delivery catheter 70 is
shown for use with the system of FIG. 1. The delivery catheter 70
is delivered through the first and second catheters described
above. The catheter delivers an expandable device 4A to the
aneurysm through the second catheter 8 (see FIG. 1).
[0102] The delivery catheter 70 has an expandable member 72,
preferably a balloon 74, for deploying the expandable device 4A.
The device 4A is configured to retain the expanded position of FIG.
12 after the balloon 74 has been deflated. The delivery catheter 70
has an inflation lumen 72 coupled to a source of inflation fluid 74
for inflating the balloon (FIG. 1).
[0103] The expandable device 4A is preferably made of a number of
flexible filaments 76. The filaments 76 are preferably woven or
braided but may also be a number of non-woven filaments. The
filaments 76 may be any suitable material and a preferred material
is platinum alloy (92% platinum, 8% tungsten) wire having a
thickness of 0.005-0.003 inch.
[0104] The expandable device 4A may take any shape and may have a
number of predetermined shapes which can be selected depending upon
the shape of the aneurysm and the nature of the patient's
vasculature. Referring to FIG. 12, the expandable device 4A has a
simple spherical shape. Although the expandable device 4A is shown
as spherical, the expandable device 4A preferably has a width to
height ratio of more than 1.1, more preferably at least 1.2 and
most preferably at least 1.8. The width and height are defined
relative to the aneurysm (FIG. 12) and/or relative to a
longitudinal axis 76 of the expandable device 4A. The preferred
dimensions provide a relatively large width so that the expandable
device 4A cannot escape through the neck of the aneurysm after
expansion. The height of the expandable device 4A provides
clearance for shrinking the aneurysmal toward the expandable
device. The width to height ratios are preferred dimensions for all
of the embodiments described herein.
[0105] Once the expandable device 4A has been delivered to the
aneurysm, the aneurysm is preferably reduced in size in any manner
described herein. A method of reducing the size of the aneurysm is
to deliver energy to the expandable device 4A from the energy
source 12. The energy may be delivered to the aneurysm by
delivering RF energy to the expandable device 4A with one or more
wires 80 passing through the second catheter 8. During RF delivery,
the second catheter 8 may be used to deliver fluid, such as
hypertonic saline, to the aneurysm.
[0106] Referring to. FIGS. 14 and 15, simple resistance heating may
also be used by moving the wires 80 into contact with the
expandable device 4A to conduct electricity therebetween as shown
in FIG. 14. An advantage of the system is that different portions
of the aneurysm can be heated to shrink the aneurysm as shown in
FIGS. 14 and 15.
[0107] The expandable device 4A may be insulated at a proximal
portion 82 so that energy is delivered to the aneurysm dome rather
than toward the neck and parental artery. The flexible filaments 76
may be coated with any suitable insulation, such as paraline, and
may be applied by spraying, dipping or etching. The expandable
device 4A may also have the flexible sheath 78 over the insulated
region to further shield the neck of the aneurysm.
[0108] Referring to FIGS. 16, a heating device 84 is shown which
may be used to heat and shrink the aneurysm. The heating device 84
is advanced into the aneurysm to heat fluid in the aneurysm thereby
heating and shrinking the aneurysmal wall. Two insulated wires 86,
88 are wrapped around a core wire 90 and covered with a sheath 92
along the proximal portion. The sheath 92 forms a lumen 94
therethough which may be coupled to the various sources 18, 20, 22,
24 described above with connector 96. The distal end of the wires
86, 88 form proximal and distal electrodes 98, 100 for bipolar RF
heating. The core wire 90 is attached to the distal electrode
100.
[0109] An actuator 102 is manipulated to change the distance
between the electrodes 98, 100 and to bend the tip in the manner
shown in FIG. 17. The actuator 102 is coupled to the core wire 90.
The device may be configured so that the electrodes 98, 100 move
toward another when the actuator 102 is manipulated, or the device
may be configured so that the tip curves as shown in FIG. 17. The
tip may be curved to navigate tortuous vessels and may be curved
during heating. In use, the distal end of the device 84 is
introduced into the aneurysm and the actuator 102 is manipulated to
curve the distal end. RF energy is then delivered and a fluid, such
as hypertonic saline, is delivered through the second catheter 8 or
through the lumen 94.
[0110] Referring to FIGS. 18 and 19, the aneurysm may be shrunk
into contact with the expandable device so that the expandable
device 4A reinforces the aneurysmal wall to prevent rupture. The
aneurysmal wall may also be shrunk further so that the expandable
device 4A itself shrinks as shown in FIG. 20. After the aneurysm
has been reduced in size, the sealant 64 may also be delivered to
further seal the aneurysm.
[0111] Referring to FIGS. 1 and 21-24, another delivery catheter
110 for treating an aneurysm with the system 2 of FIG. 1 is shown.
The catheter 110 is advanced to the carotid artery and the second
catheter 8 is advanced through the first catheter 6 to the
aneurysm. The delivery catheter 110 extends through the second
catheter 8 to deliver an expandable device 4B to the aneurysm. The
delivery catheter 110 has a lumen 112 which may be coupled to one
or more of the various sources 18, 20, 22, 24. The expandable
device 4B is coupled to the energy source 12 for heating and
shrinking the aneurysm as will be described below.
[0112] The expandable device 4B is movable from the collapsed
position of FIG. 21 to the expanded position of FIG. 22. Flexible
filaments 114 preferably form a woven or braided mesh structure 116
extending between first and second hubs 118, 120. A central post
122 extends from the second hub 120 and has a locking Mechanism 124
which engages the first hub 118 to hold the expandable device 4B in
the locked position. An actuator 126, which is preferably a tapered
rod 128, has a threaded connection 130 with the central post 122.
The actuator 126 is pulled to move the locking mechanism 124 into
engagement with the second hub 120. The locking mechanism 124 has
spring elements 126 which are naturally biased to the position of
FIG. 23. The spring elements 126 are angled proximally so that they
are displaced inwardly by the hub 118 when the post 122 and spring
elements 126 pass through the hub 118. After the spring elements
126 have passed through the hub 118 they assume their unbiased
shape thereby locking the device 4B in the expanded position. The
locking mechanism 124 may be any suitable locking mechanism.
[0113] The flexible filaments 114 preferably bias the device 4B
toward the collapsed position so that the operator may partially
expand the device to determine whether the device has the
appropriate size. If the device is not the appropriate size, the
device can be collapsed and withdrawn through the second catheter
8. After the expandable device 4B has been expanded, the aneurysmal
wall may then be shrunk in any manner described herein. In the
preferred embodiment of FIG. 21, the expandable device is a
monopolar RF electrode with the energy source being an RF generator
coupled to the actuator 126. The expandable device 4B may be
insulated along a proximal portion 116 to protect the neck,
parental vessel and adjacent vessels as mentioned above. After the
aneurysmal wall has been reduced in size, the sealant 64 (FIG. 8)
may be introduced to isolate the aneurysm from the parental
vessel.
[0114] In another aspect of the present invention, the expandable
devices 4, 4A, and 4B may be filled with an expandable thrombogenic
material 130. Referring to FIG. 10, the expandable device 4 is
filled with the compressible, thrombogenic material 130 which may
be randomly oriented fibers 132 or coils 134. When the expandable
device 4 is expanded, the material 130 expands to occupy the
interior volume of the woven or braided mesh structure 42. The
material 130 may be used with any of the expandable devices
described herein without departing from the scope of the invention.
When the material 130 includes filaments 136, the filaments 136 may
be helically, radially or randomly oriented within the interior
volume of the mesh or braided structure 42.
[0115] Referring to FIGS. 1 and 24-27, another catheter 140 for
treating an aneurysm with the system of FIG. 1 is shown. The first
catheter 6 is introduced through the femoral artery and advanced to
the carotid artery. The second catheter 8 is, advanced through the
first catheter 6 to the aneurysm. The delivery catheter 140 is
passed through the second catheter 8 to the aneurysm to treat the
aneurysm.
[0116] The delivery catheter 140 has a lumen 142 which is coupled
to the sources of fluid, contrast, sealant and vacuum 18, 20, 22,
24. The distal end of the catheter 140 has a cover 144 which is
positioned over the neck of the aneurysm as shown in FIG. 27. The
cover 144 provides temporary isolation of the aneurysm from the
parental vessel. The cover 144 is preferably a disc of relatively
soft material such as silicone. The cover 144 is preferably
configured to cover an area of about 0.8 mm.sup.2 to 75 mm.sup.2
and is relatively thin so that the cover 144 does not impede flow
through the parental vessel and so that the cover 144 can distort
to a small profile when passing through the second catheter 8. The
cover 144 is also preferably impermeable so that the cover 144 can
isolate the aneurysm from the parental vessel.
[0117] The catheter 140 has an electrode 146 which is coupled to
the energy source 12 with a wire 148 extending through the catheter
140. The electrode 146 may be configured as a monopolar RF
electrode for delivery of RF energy with a second electrode (not
shown) in contact with the patient's skin. Alternatively, a second
electrode 150 may be passed through the lumen 142 to provide
monopolar or bipolar RF with the first and/or second electrodes to
146, 150. Shrinking of the aneurysm may, of course, be accomplished
with any of the methods described above. For example, the heating
device 84 (FIG. 16) may be advanced through the lumen 142 to heat
and shrink the aneurysm.
[0118] Use of the delivery catheter 140 is now described, the
delivery catheter 140 is advanced through the second catheter 8 to
the aneurysm. The cover 144 is positioned over the neck of the
aneurysm and the aneurysm is heated to shrink the aneurysm. When
using RF heating, fluid such as hypertonic saline may be infused
into the aneurysm through the catheter 140 or second catheter 8
(FIG. 1). The cover 144 may be flexible enough to deflect and
permit hot fluid to be slowly expelled into the parental vessel.
Alternatively, the cover 144 may be periodically moved away from
the neck so that hot fluid in the aneurysm may be slowly expelled
into the parental vessel. The aneurysm may be reduced to an
acceptable size or partially shrunk and filled with the
thrombogenic material 130 and sealant (FIG. 28) or just the
material 130 (FIG. 29). Although the delivery catheter 140, and
particularly the cover 144, have been described in connection with
RF delivery, the cover 144 may be incorporated into any of the
other catheters described herein or any other catheter without
departing from the scope of the invention.
[0119] Referring to FIGS. 30-34, another expandable device 160 is
shown for use with the system of FIG. 1. The expandable device 160
is advanced through the second catheter 8 with a delivery catheter
162. The expandable device has a mesh 166 which covers a spring 160
made of a shape memory material. The expandable device 160 is in
the collapsed shape of FIG. 30 when advanced through the second
catheter 8. After the expandable device 160 is within the aneurysm,
a wire 161 or other device can be advanced to contact the device
160 to heat the device and the aneurysm. Upon heating, the coil
collapses to the shape of FIG. 31 to move the mesh 166 to the
expanded condition. Heating of the coil may be undertaken in any
manner described herein. An advantage of the device 160 is that the
device may be heated together with the aneurysm to deploy the
device 160 while shrinking the aneurysm. Referring to. FIG. 32,
another device 160A is shown which is substantially the same as the
device 160 except that spring 160A expands in the middle. FIG. 33
shows still another device 160B which has a smaller diameter in the
middle to impede fluid flow through the spring 160.
[0120] Referring to FIG. 34, another mesh 42A is shown. The mesh
42A may be used with any of the expandable devices described herein
and the mechanism for expanding and holding the mesh 42A has been
omitted from FIG. 34 for clarity. Any of the actuating and delivery
methods and devices described above or any other suitable device
may be used with the mesh 42A. The mesh 42A preferably has 10-50
filaments, more preferably 20-50 filaments, extending between first
and second ends 150, 152. The filaments 148 are preferably platinum
alloy (such as 92% platinum, 8% tungsten). The filaments 148
preferably form a tube in the collapsed position which has a
diameter of no more than 0.020 inch but expands to a diameter of at
least 0.200 inch at a central portion 154.
[0121] The devices described herein are preferably delivered to the
aneurysm to occupy the remaining volume of the aneurysm after
shrinking the aneurysm. Referring to FIGS. 35 and 36, a number of
devices 170 may be delivered to the aneurysm with one of the
devices 171 being used to heat and shrink the aneurysm. The devices
170 may be partially or completely insulated in the manner
described above to protect the neck while heating and shrinking is
accomplished with the device 171. The devices 170 and 171 are shown
spaced apart for clarity but, of course, will be closely packed
together when filling the aneurysm. The devices 170 and 171 may be
any of the expandable devices described herein or any other
suitable device without departing from the scope of the
invention.
[0122] Referring to FIG. 37, another system for reducing the size
of an aneurysm is shown. A coil 172 is used to regulate flow of
fluid between the aneurysm and the parent vessel. The coil 172 is
particularly useful for holding heated fluid in the aneurysm to
heat and shrink the aneurysm. The heating device 84 of FIGS. 16 and
17, or any other suitable device for heating the aneurysm, is
introduced into the aneurysm to heat and shrink the aneurysm. The
coil 172 is manipulated by pulling or pushing the coil to retract
or deploy the coil 172 from the catheter 8 (see FIG. 1). The pitch
of the coil 172 can be varied by pulling or pushing the catheter 8
relative to the coil 172. The windings of the coil 172 may be close
together so that the coil 172 substantially impedes flow between
the aneurysm and the parent vessel (FIG. 38) or may be spaced-apart
to permit slow leakage of fluid into the parent vessel. The coil
172 may be made of any suitable material and is preferably a
shape-memory alloy such as nitinol.
[0123] Referring to FIGS. 39 and 40, another catheter 180 for
heating and shrinking an aneurysm is shown. The catheter 180 is
preferably less than 5 Fr, more preferably 2-4 Fr, and most
preferably about 3 Fr in size so that it is small and flexible
enough to shrink select portions of the aneurysm as shown by dotted
lines 181 in FIG. 39. The catheter 180 may, of course, be sized
larger to shrink larger portions of the aneurysm or other tissue
structures. The catheter 180 has a tip 182 which is made of a
heat-resistant, non-stick material (such as PTFE) so that the tip
can contact the tissue during heating without sticking to the
tissue. The catheter 180 may also be a hypotube, guidewire or
similar device without departing from the scope of the invention.
The tip 182 forms a chamber 183 and has holes 186 formed therein
for delivery of a conductive fluid as described below.
[0124] The catheter 180 has a lumen 184 which communicates with
the, chamber 183 in the tip 182. The lumen 184 is coupled to the
source of fluid 18 (see FIG. 1) which is preferably hypertonic
saline. An RF probe 188 passes through the lumen 184 and is coupled
to the energy supply 12 (see FIG. 1) which is preferably an RF
generator. The RF probe 188 has an electrode 189 positioned in the
chamber while a second electrode (not shown) is positioned in
contact with the patient's skin in the conventional manner. When
the conductive fluid is delivered through the lumen 184, electrical
energy is conducted by the conductive fluid to heat the aneurysm.
The holes 183 in the tip 182 may be distributed around the tip 182
(FIGS. 39 and 41), positioned at the distal end 185 (FIG. 42) or
along the sides 187 (FIG. 43) of the tip 182.
[0125] After the volume of the aneurysm has been reduced, the
aneurysm may be treated in any other manner described herein.
Furthermore, the catheter 180 of FIGS. 39-43 may be used to heat
tissue or fluid in connection with any of the other embodiments
described herein and in particular as a substitute for the device
84 of FIGS. 16 and 17. Finally, the catheter 180 may be used to
heat tissue for any other suitable purpose including those
described above. For example, the catheter 180 may be useful in
treating venous insufficiency, deep vein reflux or for vein
stripping. Furthermore, the catheter 180 may be useful for treating
urinary incontinence.
[0126] While the above is a description of the preferred
embodiments of the invention, various alternatives, modifications,
and equivalents may be used. For example, the expandable device may
take any other shape and the sealant may be any other suitable
sealant. Furthermore, the dimensions and characteristics of any of
the expandable members may be incorporated into any of the other
expandable devices described herein without departing from the
scope of the invention. Finally, the expandable devices are
preferably used when shrinking the aneurysm but the expandable
devices may have various features which may be useful when simply
filling the aneurysm in the conventional manner.
[0127] Referring to FIG. 43-46, another device 200 for treating an
aneurysm is shown. The device 200 has a cover 202 that covers the
neck of the aneurysm. The device 200 also has a lateral extension
204 extending from the cover 202 into the aneurysm. The lateral
extension 204 positions the cover 202 over the neck of the aneurysm
and anchors the device 200 to the aneurysm.
[0128] The cover 202 may be any suitable structure such as a patch
or tube so long as the cover 202 is able to block the neck of the
aneurysm to isolate the aneurysm from the parental vessel. The
cover 202 is preferably substantially flat so that the cover 202
can lie against the wall of the parental vessel around the neck of
the aneurysm. In the preferred embodiment, the cover 202 is
preferably a mesh patch 206 made of a superelastic material such as
nitinol. The mesh 206 may have a coating or layer 208, such as
expanded PTFE, which provides the properties and advantages of
conventional graft materials. The cover 202 preferably extends no
more than one half, and more preferably no more than one third, the
circumference of the vessel. Stated another way, the cover 202
preferably extends no more than 180 degrees and more preferably no
more than 120 degrees around a longitudinal axis of the device when
expanded. Of course, the cover 202 may cover more or less of the
parental vessel without departing from various aspects of the
invention.
[0129] The lateral extension 204 preferably forms 1-8 loops 210,
and more preferably only one loop, extending from the cover 202.
The loop 210 is preferably formed by an elongate element 212 such
as a ribbon made of a superelastic or shape-memory material such as
nitinol. An end 211 of the loop 210 is attached to a guide 214
which is attached to the cover 202. The term loop 210 is intended
to include any filament, ribbon, wire or the like having two sides
coupled to the cover 202. The two sides do not have to touch or be
adjacent one another to form a loop 210 and, in fact, the loop
could be made from a continuous coil wrapped into the cover 202 so
long as the coil generally forms 1-8 individual loops 210 extending
into the aneurysm. The lateral extension 204 extends laterally from
a catheter 216 during deployment so that the catheter 216 can
remain aligned with the vessel in the manner shown in FIG. 45.
[0130] The elongate element 212 extends and slides through the
guide 214. The element 212 has a stop 220 at one end that engages
the guide 214 to hold the extension 204 in the expanded condition.
The element 212 is preferably biased toward the expanded position
of FIGS. 43 and 46 so that the stop 220 naturally engages the guide
214 when the element 212 is released. The element 212 is coupled to
a first manipulator 222 with a releasable connection such as a
threaded connection 223 or an electrolytically severable bond. The
first manipulator 222 is used to move and deploy the device 200,
and in particular the loop 210, in the manner described below. As
will be explained below, the device 200 is preferably available in
a number of different sizes with the size of the loop 210 and the
size of the cover 202 being variable. The size of the loop 210 and
cover 202 are selected based upon the geometry of the aneurysm and
parental vessel.
[0131] The device 200 is preferably delivered with the catheter
216. The device 200 is mounted within the catheter 216 and is
advanced out of the catheter 216 and exposed as shown in FIGS.
44-46 when deploying the device 200. The delivery catheter 200 has
a first lumen 224 in which is positioned the first manipulator 222.
A second manipulator 226 holds the cover 202 opposite the first
manipulator 222 for moving and deploying the device 200. A suture
228 or any other releasable connection holds the cover 202 to the
second manipulator 226. The catheter 216 is preferably advanced
over a guidewire 230 which is positioned in a guidewire lumen 232.
The catheter 216 preferably has a three-lumen configuration
although fewer lumens may be used without departing from the scope
of the invention.
[0132] The device 200 may also be operated by delivering energy,
such as RF energy, to the device 200 as now described in connection
with methods and systems of the invention. When delivering energy,
such as RF energy, the cover 202 preferably does not conduct energy
to protect the parental vessel and neck of the aneurysm.
[0133] Additional methods of the present invention are now
described in connection with the preferred embodiment of FIGS.
43-46 although other suitable devices may be used. Before
introducing the device 200 into the patient, the geometry of the
aneurysm and parental vessel are determined so that the appropriate
size of the device 200 is used. For example, the size of the
extension 204 may be selected to be somewhat smaller than the
aneurysm particularly when heat is used to shrink the aneurysm with
RF energy or the like. The device 200 may also form a number of
different shapes that are selected based on the geometry of the
aneurysm.
[0134] After selecting the appropriate size of the device 200, the
device 200 is introduced into the patient with the catheter 216 in
the manner described above and the methods and systems described
above are specifically incorporated here. When the device 200 is
positioned at the aneurysm, the distal end of the cover 202 and the
lateral extension 204 are advanced out of the catheter 216 by
manipulating the first and second manipulators 222, 226. The first
and second manipulators 222, 226 may be used to expand and retract
the device 200 a number of times when attempting to introduce the
extension into the aneurysm. Once the extension 204 is properly
positioned within the aneurysm, the extension 204 expands to occupy
space within the aneurysm.
[0135] Energy may then be delivered to the lateral extension 204 to
shrink the aneurysm and/or simply adhere the extension to the
aneurysmal wall thereby holding the cover in the proper position.
The source of RF energy is coupled to the first manipulator 222 for
this purpose. Although the invention may be practiced with delivery
of RF energy, various aspects may be practiced without delivering
energy to the aneurysm. The device 200 is then released to permit
the cover 202 to expand as shown in FIG. 46. The lateral extension
204 helps to orient the cover 202 into the proper position as the
cover 202 expands.
[0136] Referring to FIGS. 47-50, still another device 250 for
treating an aneurysm is shown. The device 250 has a cover 252
wrapped around an expandable element 254 such as an inflatable
balloon 256. The balloon 256 is inflated through an inflation lumen
257. A sheath 258 extends over the cover 252 to trap the cover 252
between the sheath 258 and expandable element 254. The sheath 258
is retracted to expose the cover 252 when deploying the cover 252
as explained below. The sheath 258 is preferably folded over itself
at the distal end and is folded back and everted to expose the
cover 252. The sheath 258 is preferably made of a flexible material
at the distal end such as a suitable polymer such as polyethylene.
The guidewire may engage the expandable element 254 at a connection
259 so that the guidewire helps to stabilize the device 250 during
deployment.
[0137] The cover 252 is preferably wrapped or collapsed by simply
wrapping the cover 252 around the expandable element 254. The cover
252 may overlap itself or may extend around only part of the
expandable element 254. In the preferred embodiment, the cover 252
is wrapped around the expandable element 254 without any
overlapping flaps, folds or sections.
[0138] The cover 252 is preferably adhered to the wall of the
parental vessel around the neck of the aneurysm. The cover 252 may
be adhered to the wall with any suitable method including glue or
heat. The cover 252 may also be adhered to the wall using a
conventional stent or with a support structure similar to a stent.
In a preferred method, the cover 252 is adhered to the parental
vessel with a biocompatible adhesive 260 such as cyanoacrylate
applied to an outer surface of the cover 252. The sheath 258 covers
the adhesive 260 during introduction and advancement of the device
250. The adhesive 260 may also be activated within the patient
using light, heat, RF, radiation, chemical or other suitable
activators.
[0139] Referring to FIG. 51, another cover 262 is shown for use
with the device 250 wherein the same or similar reference numbers
refer to the same or similar structure. The cover 262 has a frame
264, preferably metallic, and an impermeable portion 266 mounted to
the frame 264. The impermeable portion 266 is preferably PTFE or
expanded PTFE and is fused or sutured to the frame 264. The
impermeable portion 266 covers the neck of the aneurysm to isolate
the aneurysm.
[0140] Referring to FIG. 52-56, another device 300 for treating an
aneurysm is shown. The device 300 has a number of filaments 302
that extend from a proximal hub 304 to a distal hub 306. The
filaments 302 are preferably stainless steel, platinum or nitinol
and the hubs 304, 306 are preferably platinum or a radiopaque
polymer. The filaments 302 are attached to the hubs 304, 306 by
solder, weld or glue. The device 300 preferably includes 2-16
filaments 302 and more preferably about 8 filaments 302. The
filaments 302 may be integrally formed with one or both of the hubs
304, 306 or may be a single filament 302 which is wound around or
adhered to the hubs 304, 306. The device 300 preferably assumes a
generally dish-shaped structure having a generally convex side 308
and a concave side 310 although the device 300 may take any other
suitable shape.
[0141] The device 300 is advanced through a catheter 312 with a
manipulator 314. The device 300 may, of course, be mounted within a
sheath (not shown) which is then advanced through the catheter 312
as described above. The manipulator 314 may simply push the device
300 or the device may be releasably attached to the device 300 with
a mechanical connection or an electrolytically severable bond. When
the device 300 exits the catheter 312, the distal hub 306 is
naturally biased toward the proximal hub 304 with the filaments 302
forming loops 314 when expanded (see FIG. 54).
[0142] The device 300 may be coupled to a source of energy, such as
a source of RF energy, which is delivered to heat the device 300 to
adhere the device 300 to the aneurysm and/or shrink the aneurysm.
The device may also be used with other methods of closing an
aneurysm such as with a sealant or with conventional coils and the
like. The device 300 prevents such embolic material from migrating
out of the aneurysm.
[0143] Referring to FIGS. 57-61, yet another device 316 for
treating an aneurysm is shown. The device 316 has a manipulator 318
which may simply push the device 316 through a lumen 320 in a
catheter 322 or may be releasably attached in any suitable manner.
The device 316 has a plurality of filaments 324 each having a
proximal end 326 and a distal end 328. The proximal ends 326 are
coupled together at a hub 330.
[0144] The filaments 324 are collapsed into a relatively
straightened configuration when positioned in the catheter 322.
When the filaments 326 are deployed out of the catheter 322, the
filaments 324 expand to occupy space in the aneurysm. The filaments
324 may expand into any suitable shape and preferably expand to
form a number of coils 328. The coils 328 may be oriented in any
manner and are preferably oriented with a central axis 330 of at
least three coils 328 lying in a common plane 330. The device 316
may have 2-6 coils 328 and FIG. 59 shows three coils and FIGS. 60
and 61 show two different four coil 328 configurations. The device
316 is deployed in substantially the same manner as the device
described above. The catheter 322 is advanced to the aneurysm and
the manipulator 318 moves the device 316 out of the catheter and
into the aneurysm as shown in FIG. 58.
* * * * *