U.S. patent application number 14/210193 was filed with the patent office on 2014-09-18 for continuous embolic coil and methods and devices for delivery of the same.
The applicant listed for this patent is ENDOSHAPE INC.. Invention is credited to William Aldrich, Charles Barkenbus, Jeffrey Castleberry.
Application Number | 20140277097 14/210193 |
Document ID | / |
Family ID | 50625125 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140277097 |
Kind Code |
A1 |
Castleberry; Jeffrey ; et
al. |
September 18, 2014 |
CONTINUOUS EMBOLIC COIL AND METHODS AND DEVICES FOR DELIVERY OF THE
SAME
Abstract
An occlusion system provides a trimmable continuous embolic coil
that is "cut to length" at the end of its deployment into the
aneurysmal space. A delivery device provides the "cut to length"
feature for the continuous embolic coil. A method of filling an
aneurysmal space with a continuous embolic coil is also
disclosed.
Inventors: |
Castleberry; Jeffrey;
(Longmont, CO) ; Aldrich; William; (Napa, CA)
; Barkenbus; Charles; (Longmont, CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ENDOSHAPE INC. |
Boulder |
CO |
US |
|
|
Family ID: |
50625125 |
Appl. No.: |
14/210193 |
Filed: |
March 13, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61779360 |
Mar 13, 2013 |
|
|
|
Current U.S.
Class: |
606/200 |
Current CPC
Class: |
A61B 17/12113 20130101;
A61B 2017/0053 20130101; A61B 2017/12054 20130101; A61B 2090/3966
20160201; A61B 17/12118 20130101; A61B 2017/00867 20130101; A61B
2017/00367 20130101; A61B 2017/00871 20130101; A61B 17/12109
20130101; A61B 17/12031 20130101; A61B 17/12145 20130101 |
Class at
Publication: |
606/200 |
International
Class: |
A61B 17/12 20060101
A61B017/12 |
Claims
1. A method of filling an aneurysmal space with continuous embolic
coil, the method comprising loading a distal end of a continuous
embolic coil into a delivery device; advancing the continuous coil
into and through the delivery device from a coil dispenser;
deploying a portion of the continuous embolic coil to a desired
length into the aneurysmal space through the delivery device;
determining whether a coil pack formed by the deployed portion of
the continuous embolic coil is sufficient to partially or
completely fill the aneurysmal space; cutting the continuous
embolic coil at the desired length such that the deployed portion
of the continuous coil is severed from the coil dispenser and a
proximal portion of the continuous coil remains on the coil
dispenser.
2. The method of claim 1 further comprising advancing a proximal
portion of the deployed portion of the continuous embolic coil
remaining in the delivery device into the aneurysmal space to join
or complete a coil pack.
3. The method of claim 1 further comprising deploying a second
length of the continuous embolic coil into the aneurysmal space
without reloading the delivery device with a second continuous
embolic coil.
4. The method of claim 1 further comprising moving the delivery
device to a second aneurysmal space; and deploying the continuous
embolic coil at the second aneurysmal space.
5. The method of claim 1, wherein the aneurysmal space is a void
defined between an endograft device and a patient's aorta or the
space is an arterial-venous malformation (AVM).
6. The method of claim 1, wherein the delivery device includes a
proximal end located outside of the patient's body and a distal end
positioned within the aneurysmal space; and the cutting operation
is performed at the proximal end of the delivery device.
7. The method of claim 1, wherein the delivery device includes a
proximal end located outside of the patient's body and a distal end
positioned within the aneurysmal space; and the cutting operation
is performed at the distal end of the delivery device.
8. The method of claim 1, wherein the loading operation comprises
manually advancing the coil from the coil dispenser to the delivery
device.
9. The method of claim 1, wherein the continuous embolic coil is a
shape memory polymer coil or a radiopaque polymer coil.
10. A method of occluding a target occlusion site with a continuous
embolic coil, the method comprising advancing a distal end of a
continuous embolic coil from a coil dispenser into and through a
delivery device; deploying a portion of the continuous embolic coil
into the target occlusion site through the delivery device;
visualizing the coil pack to determine whether a coil pack formed
by the continuous embolic coil is sufficient to partially or
completely fill the occlusion site; cutting the continuous embolic
coil such that the deployed portion of the continuous coil is
severed and a proximal portion remains on the coil dispenser.
11. The method of claim 10 further comprising advancing a proximal
portion of the deployed portion of the continuous embolic coil
remaining in the delivery device into the target occlusion site to
join or complete a coil pack.
12. The method of claim 10 further comprising deploying a second
length of the continuous embolic coil into the target occlusion
site without reloading the delivery device with a second continuous
embolic coil.
13. The method of claim 10 further comprising moving the delivery
device to a second target occlusion site; and deploying the
continuous embolic coil at the second target occlusion site.
14. The method of claim 10, wherein the target occlusion site is an
aneurysmal space that is a void defined between an endograft device
and a patient's aorta or the space is an arterial-venous
malformation (AVM).
15. The method of claim 14, wherein the delivery device includes a
proximal end located outside of the patient's body and a distal end
positioned within the aneurysmal space; and the cutting operation
is performed at the proximal end of the delivery device.
16. The method of claim 14, wherein the delivery device includes a
proximal end located outside of the patient's body and a distal end
positioned within the aneurysmal space; and the cutting operation
is performed at the distal end of the delivery device.
17. The method of claim 10, wherein the advancing operation
comprises manually advancing the coil from the coil dispenser or
tubular holding body into the delivery device.
18. The method of claim 10, wherein the continuous embolic coil is
a shape memory polymer coil or a radiopaque polymer coil.
19. A system for filling an aneurysmal space, the system comprising
a continuous radiopaque embolic coil configured to be cut to length
and when deployed into the aneurysmal space, the coil transitions
from a storage shape to a deployed shape to form, join or complete
a coil pack.
20. The system of claim 19 further comprising a coil dispenser
configured to receive and maintain the coil in the storage shape
and deploy the continuous embolic coil into the aneurysmal space.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority of U.S.
Application No. 61/779,360, filed Mar. 13, 2013 and entitled
Continuous Embolic Coil and Methods and Devices for Delivery of the
Same, which is hereby incorporated by reference as though fully set
forth herein.
[0002] The following applications are related to the present
disclosure: PCT/US11/046829, filed Aug. 8, 2011 and entitled
"Radiopaque Shape Memory Polymers for Medical Devices"; and U.S.
patent application Ser. No. 13/262,546 filed Sep. 30, 2011 and
entitled "Vascular Occlusion Devices", each of which are hereby
incorporated by reference as though fully set forth herein.
TECHNICAL FIELD
[0003] The disclosure relates generally to implantable devices for
therapeutic treatment, and more particularly relates to an
endoluminally delivered device for vascular occlusion and methods
and devices for delivery of the same.
BACKGROUND
[0004] During many clinical procedures, a physician requires the
reduction or complete stoppage of blood flow to a target region of
the patient's body to achieve therapeutic benefit. A variety of
devices are available to provide occlusion of blood vasculature
including embolic coils, metal-mesh vascular plugs, beads,
particles and glues. Interventional radiologists and vascular
surgeons (and similar medical specialists) draw from these
therapeutic options based upon the specific need and confidence of
a rapid and effective occlusion given the attributes and
deficiencies of each of these options. These devices may be used to
occlude vasculature in situations requiring treatment, for example,
of arteriovenous malformations (AVMs), traumatic hemorrhage,
fistulae, some aneurysm repair, uterine fibroid, and tumor
embolization. For these clinical treatments, the blood flow through
a target section of a blood vessel, aneurysm or defect must be
stopped. The device is introduced into the blood vessel through a
sterile delivery catheter or sheath using common percutaneous
access outside the body. The delivered, artificial device induces
an initial reduction of blood flow through a simple mechanical
blockage which in turn triggers the body's natural clotting process
to form a more complete blockage comprised of the thrombus adhered
to the device.
[0005] One specific clinical purpose is to fill an aneurysm space,
or sack, that resides behind an endograft for repair of Abdominal
Aortic Aneurysms. The endograft is intended to isolate a weakened
vessel wall in the aorta from blood pressure and thereby reduce the
risk of rupture. While the graft may successfully isolate the
aortic blood flood, side branches and feeders may connect into the
aneurysm sack and continue to present blood pressure on the
weakened vessel wall. One attempt for resolution is to access this
sack behind the endograft and fill this space with embolic coils.
Access may be performed through a catheter, trocar or needle
cannula, the latter may be through tissue by puncturing the
aneurysmal wall. As this space can be relatively large, independent
coils of defined length can only contribute a small percentage of
displacement. In order to fill this space, a very large number of
metallic coils may be used resulting in a very large metal mass to
reduce blood flow and ultimately achieve flow stasis in the sack
behind the graft. This is very costly, requires considerable x-ray
exposure to both physician and patient, and the resulting metal
mass can detrimentally affect post procedure patient imaging with
either CT or MR scanning.
[0006] Current embolic coils are made from biocompatible materials
and provide a biodurable, stable blockage of blood flow. The coils
anchor to the vessel wall or aneurysm through radial compliance
pressing onto the vessel wall surface. Coils must be suitably
anchored to avoid migrating downstream under the forces of the
blood flow, which can be significant in larger vasculature. Embolic
coils are often shaped for flexibility through a primary coiling
and for achieving a "coil pack" within the vessel through a
secondary, sometimes complex, three dimensional shape. The coil
pack appears as a relatively random crossing and intertwining of
the coil within the vessel. After slowing the blood flow, over
time, a clot forms around the embolic coil and blood flow through
the section is completely blocked.
[0007] Typical embolic coils are formed by two major steps: 1) a
wire of platinum or other bio-compatible material is wound into a
spring, forming what is commonly referred to as a primary coil; and
2) the primary coil is in turn wound around a mandrel having a more
complex shape and is subject to high heat to yield a secondary
coil. The secondary coil is thus a coiled wire of complex shape or,
if helical, a larger curl diameter. Coils can also be provided in
multiple secondary shapes including multiple helical curl diameters
and in tapered helical shapes with one end employing a large curl
diameter and the other end a small curl diameter. These metal coils
are straightened, within their elastic bending limit, so as to be
advanced into a delivery catheter and pushed down the catheter by a
guide wire, pusher, or a detachable pre-attached pusher, until
expelled into the vessel. Often, polymeric fibers are applied to
the metallic coils in order to increase a thrombus response in
addition to providing a scaffolding for thrombus to adhere to and
be retained on the coil.
[0008] Embolic coils are sized to fit within the inner lumen of a
catheter or sheath to be delivered to the target occlusion site
individually and sequentially. Typically, a physician will use
multiple coils of discrete lengths to occlude a single vessel and,
in some cases, especially for larger blood vessels (above 5 mm or
so), the physician may use a significant number of coils to achieve
cessation of blood flow. To complete an occlusion procedure with
embolic coils, the physician must sequentially reload the catheter
with several individual coils until he/she has determined the
occlusion is sufficient. The physician typically determines whether
sufficient coils have been deployed by assessing the level of
occlusion of the vessel flow by using contrast media in concert
with typical medical imaging techniques. This "place and assess"
method can extend the medical procedure time, expose the patient to
increased levels of contrast agent, and expose both the patient and
the physician to increased radiation through extensive imaging.
[0009] Embolic coils are also known for challenges in achieving
precise vascular placement. Many of these coils are simply pushed
out of the end of a delivery catheter. The final coil pack location
is dependent upon whether the coil has been properly sized before
deployment and whether the coil was properly anchored into a side
vessel/branch as prescribed by several of the coil manufacturers
for greater confidence in the final position of the coil packs.
Both of these techniques require a high level of physician skill if
there is a desire to accurately position both the distal and
proximal faces of the coil pack in a vessel using sequential,
pushable coils. Some of the coil manufacturers provide a detachable
coil- a device that encompasses a coil of discrete length,
removably attached to a second delivery system or control wire. At
the physician's discretion a placed coil can be released from a
delivery control wire. If the coil is not in the proper location it
can be retracted and replaced if needed to achieve better position
before release. Only the proximal end of the coil is attached to
the control wire, resulting in only indirect control of the
position of the coil pack's distal face.
[0010] Using coils for embolization can present other unique
challenges. Voids in the coil pack, developed either during the
procedure or post-operatively, can cause channels and resulting
blood flow in an unintended area. This condition is typically
referred to as recanalization. Depending upon the significance of
the condition (e.g., internal hemorrhage), retreatment or surgical
intervention may be necessary. The sequential use of independent
coils of fixed lengths can be a very time consuming procedure where
the intended target is a large vessel. An intraoperative outcome
may appear stable and occluded, but greater certainty could be
achieved by placing one or more additional coils. However, the
challenges of deploying one additional coil to further increase the
coil pack density may not be deemed desirable given the coil cost
and time involved with placement. The ability to quickly and
reliably develop a consistently dense coil pack in a vessel is an
important characteristic of a successful vascular occlusion product
or aneurysm filling device.
[0011] In addition, independent embolic coils can be easily
misplaced. Embolic coils may either be injected through a delivery
catheter with a syringe filled with saline, pushed by an
independent guide wire, or deployed with a detachable pusher that
is only connected to the coil via its proximal end. The coil pack
shape is dependent upon the successful placement of the initial
coil and the ability to engage the subsequent coils in an
intermixed and tangled mass of high density. Accordingly, coils can
easily be misplaced should the initial coil not land correctly or
be slightly undersized to the target vessel and slip beyond the
target location. As such, embolic coil packs are known for a high
propensity of being elongated in overall size. While these devices
have been employed clinically for years and the technique is
generally accepted, coils present significant challenges when
attempting to embolize in a very precise or limited section of
vasculature.
[0012] Metal mesh vascular plug devices have also been developed
and commercialized to achieve vascular occlusion. These devices
achieve occlusion with a single deployment using a metal mesh to
provide mechanical flow blockage and, after some time, thrombus
forms and a complete occlusion results. When deployed, these
devices assume the form of metal mesh balloons or baskets, with one
or more lobes contacting the vascular wall, but with defined
proximal and distal faces. With occlusion occurring after a single
device deployment, these products address many of the deficiencies
of embolic coils. However, due to the porosity of the mesh basket
and the lack of the polymeric fibers used in coils, the metal mesh
plugs have been shown to take longer to achieve occlusion than a
properly placed embolic coil pack. Further, the fixed shape of
these devices makes them unattractive for use in odd-shaped spaces
such as an aneurysm sack that occurs behind an endograft stent.
[0013] Further, these metal mesh devices are relatively stiff due
to their construction and have limited ability to traverse sharp
turns found in catheters that have been placed in a highly tortuous
vascular path. The mesh is collapsed into a narrow tube-like shape
for introduction and deployment through a delivery catheter or
sheath before expanding into the balloon like shape upon
deployment. This narrow tube-like shape allows the device to be
delivered in the central lumen of small catheters or sheaths
similar to coils. However, when the mesh is collapsed, it elongates
and becomes a fairly rigid tubular structure. Thus, while being
capable of entry into a small delivery catheter, metal mesh devices
have limited ability to traverse sharp turns found in catheters
that have been placed in a highly tortuous path to reach the target
vessel for occlusion. Subsequently, the advantages of a single
occlusion device are offset by the slow and incomplete occlusion
performance and the limited application to occlusion target sites
that are less tortuous to access.
[0014] The information included in this Background section of the
specification, including any references cited herein and any
description or discussion thereof, is included for technical
reference purposes only and is not to be regarded subject matter by
which the scope of invention is to be bound.
SUMMARY
[0015] An occlusion system for occluding a target vessel or filling
an aneurysmal space is disclosed herein. The occlusion system may
include a continuous embolic coil and may include a delivery device
including a first end and a second end. The second end may include
a first tubular delivery body including a proximal end, a distal
end, and a cutting mechanism positioned in or coupled to the first
tubular delivery body. The first tubular delivery body defines a
lumen through which the continuous embolic coil is deployed into a
target vessel to be occluded or an aneurysmal space to be filled
and the cutting mechanism is configured to cut the continuous
embolic coil once a desired length of the continuous embolic coil
is deployed. In some aspects, the continuous embolic coil is a
radiopaque polymer coil. In some aspects, the continuous embolic
coil is a shape memory polymer coil. The first tubular delivery
body is a catheter or sheath. In some aspects, the first end of the
delivery device is coupled to a needle tube/hub introducer
configured to receive the continuous embolic coil. In some aspects,
the system further includes a coil dispenser which may or may not
be coupled to the needle tube/hub introducer and the coil dispenser
includes the single continuous embolic coil. The coil dispenser may
further include a coil shaped channel around which the continuous
embolic coil is wound and held within the coil dispenser until
deployment. In some aspects, the continuous coil is cut
independently of this holder at the first end of the delivery
device using sterile scissors or a scalpel with the remaining
length of coil advanced by pushing a separate guidewire through the
delivery device. In some aspects, the system may further include an
actuation mechanism to advance and/or retract the continuous
embolic coil through the delivery device. The actuation mechanism
may be a thumb wheel or a friction wheel. In some aspects, the
cutting mechanism is positioned at the proximal end of the first
tubular delivery body. In one aspect, the cutting mechanism may be
a blade positioned at a hub coupled to the proximal end of the
first tubular delivery body and the blade is deployed into the
continuous embolic coil to cut the continuous embolic coil by an
actuator button. In some aspects, the cutting mechanism is
positioned at the distal end of the first tubular delivery body. In
some aspects the cutting mechanism is a blade or other device
including a sharp edge.
[0016] In one aspect, the system further includes a second tubular
delivery body. The second tubular delivery body may be a cannula.
The second tubular delivery body may be positioned within the first
tubular delivery body, each tubular body includes a cutting
mechanism, and the bodies are configured to rotate in opposite
directions relative to each other in order to cut the continuous
embolic coil.
[0017] In some aspects, the system further includes a second
tubular delivery body having a distal end and a proximal end, a
cutting mechanism coupled to or integral with the distal end of the
second tubular delivery body, and an actuation wire coupled to the
cutting mechanism. The continuous embolic coil defines a void space
in the first tubular delivery body and the second tubular delivery
body is positioned within the void space defined in the first
tubular delivery body above or about the continuous embolic
coil.
[0018] In one aspect, where the cutting mechanism is positioned at
a distal end of the first tubular delivery body, the cutting
mechanism is a wire garrote. The wire garrote may include one wire
or two wires. The system may also include a wire actuation
mechanism, wherein a first free end and a second free end of the
wire garrote extend axially along the length of the first tubular
delivery body, and at least one free end is coupled to the wire
actuation mechanism. The system may also include a guide track
positioned within the first tubular delivery body and configured to
receive the first free end and the second free end of the wire
garrote extending axially along the length of the first tubular
delivery body.
[0019] In another aspect, the system may include a wire actuation
mechanism, a second tubular delivery body, and a ring body coupled
to a distal end of the second tubular delivery body. A first free
end and a second free end of the wire garrote extend axially along
the length of the second tubular delivery body and at least one
free end is coupled to the wire actuation mechanism. Further, the
wire garrote extends about the ring body in a non-deployed
state.
[0020] A delivery device for a continuous embolic coil for
occlusion of a target occlusion site is disclosed herein. In some
aspects, the delivery device includes a first tubular body
including a distal end and a proximal end, an introducer body and
hub coupled to the proximal end of the first tubular body, and a
cutting mechanism coupled to or positioned in the first tubular
body. The first tubular body is configured to receive the
continuous embolic coil for deployment at the target occlusion
site. The first tubular body is a catheter or a sheath. In some
aspects, the delivery device includes an actuation mechanism to
advance and/or retract the continuous embolic coil through the
delivery device.
[0021] In one aspect, the cutting mechanism is positioned at the
proximal end of the first tubular body. The device may further
include an actuator button. The cutting feature is a blade
positioned at the hub coupled to the proximal end of the first
tubular body, and the blade is deployed by the actuator button into
the continuous embolic coil to cut the continuous embolic coil.
[0022] In another aspect, the cutting mechanism is positioned at
the distal end of the first tubular body. In some aspects the
cutting mechanism is a blade or other device including a sharp
edge.
[0023] In some aspects, the delivery device further includes a
second tubular body positioned within the first tubular body. Each
tubular body comprises a cutting feature and the bodies are
configured to rotate independently of each other in order to cut
the continuous embolic coil.
[0024] In another aspect, the delivery device further includes a
second tubular body, a cutting mechanism coupled to or integral
with the distal end of the second tubular delivery body and an
actuation wire coupled to the cutting mechanism. The continuous
embolic coil defines a void space in the first tubular body and the
second tubular body is positioned within the void space defined in
the first tubular body above or about the continuous coil.
[0025] In some aspects, the cutting mechanism is positioned at the
distal end of the first tubular body and the cutting mechanism is a
wire garrote. The wire garrote may include one wire or two wires.
In one aspect, the delivery device may include a wire actuation
mechanism, wherein a first free end and a second free end of the
wire garrote extend axially along the length of the first tubular
body and at least one free end is coupled to the wire actuation
mechanism. The delivery device may further include a guide track
positioned within the first tubular body and it is configured to
receive the first free end and the second free end of the wire
garrote extending axially along the length of the first tubular
body.
[0026] In some aspects, the delivery device further includes a wire
actuation mechanism, a second tubular body, and a ring body coupled
to a distal end of the second tubular body. A first free end and a
second free end of the wire garrote extend axially along a length
of the second tubular body, at least one free end is coupled to the
wire actuation mechanism, and the wire garrote extends about the
ring body in a non-deployed state.
[0027] A method of occluding a target occlusion site with a
continuous embolic coil is also disclosed herein. In one aspect,
the method includes loading the continuous embolic coil into a
delivery device including a cutting mechanism. The continuous
embolic coil is deployed at the target occlusion site for a first
time through the delivery device. The method further includes
determining whether a coil pack formed by the continuous embolic
coil is sufficient. If so, the cutting mechanism may be deployed
via a cutting actuation mechanism. The method further includes
engaging the continuous embolic coil with the cutting mechanism to
cut the continuous embolic coil and then disengaging the cutting
mechanism from the continuous embolic coil. In some aspects, the
method further includes deploying the continuous embolic coil at
the target occlusion site for a second time without reloading the
delivery device with a second continuous embolic coil. In some
aspects, the method further includes moving the delivery device to
a second target occlusion site and deploying the continuous embolic
coil at the second target occlusion site without reloading the
delivery device with a second continuous embolic coil.
[0028] A method of filling an aneurysmal space with continuous
embolic coil is also disclosed herein. In one aspect, the method
includes loading a distal end of a continuous embolic coil into a
delivery device. The continuous coil may then be advanced into and
through the delivery device from a coil dispenser. A portion of the
continuous embolic coil may be deployed to a desired length into
the aneurysmal space through the delivery device. The method also
includes determining whether a coil pack formed by the deployed
portion of the continuous embolic coil is sufficient to partially
or completely fill the aneurysm space. If so, the continuous
embolic coil may be cut at the desired length such that the
deployed portion of the continuous coil is severed from the coil
dispenser and a proximal portion of the continuous coil remains on
the coil dispenser.
[0029] The method may further include advancing a proximal portion
of the deployed portion of the continuous embolic coil remaining in
the delivery device into the aneurysmal space to join or complete a
coil pack. In one aspect, the method further includes deploying the
continuous embolic coil into the aneurysmal space for a second time
without reloading the delivery device with a second continuous
embolic coil. In one aspect, the method further includes moving the
delivery device to a second aneurysmal space and deploying the
continuous embolic coil at the second aneurysmal space. The
aneurysmal space may be a void defined between an endograft device
and a patient's aorta. In one aspect, the delivery device includes
a proximal end located outside of the patient's body and a distal
end positioned within the aneurysmal space; and the cutting
operation is performed at the proximal end of the delivery device.
In one aspect, the delivery device includes a proximal end located
outside of the patient's body and a distal end positioned within
the aneurysmal space, and the cutting operation is performed at the
distal end of the delivery device. In one aspect, the loading
operation comprises manually advancing the coil from the coil
dispenser or tubular holding body into the delivery device. In one
aspect, the continuous embolic coil is a shape memory polymer coil.
In one aspect, the continuous embolic coil is a radiopaque polymer
coil. In one aspect, the determining operation comprises
visualization by fluoroscopy, MRI or CT imaging or a combination
thereof.
[0030] A method of occluding a target occlusion site with
continuous embolic coil is further disclosed herein. In one aspect,
the method includes advancing a distal end of a continuous embolic
coil from a coil dispenser into and through a delivery device and
deploying a portion of the continuous embolic coil into the target
occlusion site through the delivery device. The method further
includes visualizing the coil pack to determine whether a coil pack
formed by the continuous embolic coil is sufficient to partially or
completely fill the occlusion site and cutting the continuous
embolic coil such that the deployed portion of the continuous coil
is severed and a proximal portion remains on the coil
dispenser.
[0031] The method may further include advancing a proximal portion
of the deployed portion continuous embolic coil remaining in the
delivery device into the target occlusion site to join or complete
a coil pack. In one aspect, the method further includes deploying a
second length of the continuous embolic coil into the target
occlusion site without reloading the delivery device with a second
continuous embolic coil. In one aspect, the method further includes
moving the delivery device to a second target occlusion site and
deploying the continuous embolic coil at the second target
occlusion site. In one aspect, the target occlusion site is an
aneurysmal space that is a void defined between an endograft device
and a patient's aorta. In one aspect, the delivery device includes
a proximal end located outside of the patient's body and a distal
end positioned within the aneurysmal space and the cutting
operation is performed at the proximal end of the delivery device.
In one aspect, the delivery device includes a proximal end located
outside of the patient's body and a distal end positioned within
the aneurysmal space, and the cutting operation is performed at the
distal end of the delivery device. In one aspect, the advancing
operation comprises manually advancing the coil from the coil
dispenser or tubular holding body into the delivery device. In one
aspect, the continuous embolic coil is a shape memory polymer coil.
In one aspect, the continuous embolic coil is a radiopaque polymer
coil.
[0032] A method of filling an aneurysmal space with continuous
embolic coil is disclosed herein. The method includes manually
advancing a distal end of a continuous radiopaque embolic coil from
a coil dispenser and into and through a delivery device and
deploying a portion of the continuous embolic coil to a desired
length into the aneurysmal space through the delivery device. The
method further includes visualizing the coil pack to determine
whether a coil pack formed by the continuous embolic coil is
sufficient to partially or completely fill the occlusion site and
cutting the continuous embolic coil such that the deployed portion
of the continuous coil is severed and a proximal portion remains on
the coil dispenser. The method further includes advancing a
proximal portion of the deployed portion of the continuous embolic
coil remaining in the delivery device into the aneurysmal space to
join or complete a coil pack.
[0033] A system for filling an aneurysmal space is disclosed
herein. The system comprises a continuous radiopaque embolic coil
configured to be cut to length and when deployed into the
aneurysmal space, the coil transitions from a storage shape to a
deployed shape to form, join or complete a coil pack. The system
may further include a coil dispenser configured to receive and
maintain the coil in the storage shape and deploy the continuous
embolic coil into the aneurysmal space.
[0034] This Summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. This Summary is not intended to identify
key features or essential features of the claimed subject matter,
nor is it intended to be used to limit the scope of the claimed
subject matter. Other features, details, utilities, and advantages
of the present invention will be apparent from the following more
particular written description of various embodiments of the
invention as further illustrated in the accompanying drawings and
defined in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1A illustrates one embodiment of an occlusion system
including a continuous embolic coil and a delivery device, wherein
a first end of the delivery device includes a coil dispenser,
according to aspects of the present disclosure.
[0036] FIG. 1B illustrates an internal view of a second embodiment
of a coil dispenser of the delivery device of FIG. 1A, wherein the
coil dispenser includes an internal coil channel.
[0037] FIGS. 1C and 1D illustrate aspects of the occlusion system
of FIG. 1A including a continuous embolic coil and a delivery
device, wherein a first end of the delivery device includes a tube
holder configured to receive the continuous embolic coil.
[0038] FIGS. 1E through 1G illustrate the continuous embolic coil
of FIG. 1A being manually advanced to occlude a vessel as in FIG.
1F or to fill an aneurysmal space as in FIG. 1G.
[0039] FIGS. 2A-2D illustrate various cross sections of an
occlusion device that may be used with the occlusion system of FIG.
1A.
[0040] FIGS. 3A-3E illustrate an embodiment of the delivery device
of FIG. 1A having a first tubular delivery body, such as a catheter
or a sheath, and a second tubular delivery body, such as a cannula,
and a cutting mechanism at a distal end of the tubular delivery
bodies.
[0041] FIGS. 4-8G illustrate various embodiments of the delivery
device of FIG. 1A where several embodiments of a cutting mechanism
are shown which cut the occlusion device or continuous embolic coil
at a distal end of one or more tubular delivery bodies of the
delivery device.
[0042] FIG. 9 illustrates an embodiment of the delivery device of
FIG. 1A where a cutting mechanism is shown which cuts the occlusion
device or continuous embolic coil at a proximal end of a tubular
delivery body of the delivery device.
[0043] FIG. 10 is a flow diagram of an exemplary method of using an
embodiment of the occlusion system in accordance with the aspects
of the present disclosure.
DETAILED DESCRIPTION
[0044] The target anatomy for vascular occlusion (e.g., internal
hemorrhage, tumor isolation, aneurysms, AVMs, etc.) present
significant anatomical variability and in many cases, accessing
this target anatomy requires a significantly tortuous vascular path
in which the delivery catheter or delivery sheath has been placed
by a physician, such as an interventional radiologist, before
deployment of the occlusion device or continuous embolic coil. The
occlusion device or continuous embolic coil enters the tubular
delivery body, such as a delivery catheter, outside the patient's
body and travels down the delivery body to be deployed (expelled)
into the target vessel location or aneurysmal space (i.e. the
target occlusion site). At that point, the occlusion device or
continuous embolic coil forms an expanding coil pack so as to
occlude the vessel or fill the space. Therefore, a clinically
acceptable occlusion device or continuous embolic coil is flexible
to translate along the delivery body and adaptive to the structure
and shape it is filling. Further, an acceptable device will anchor
to the vessel wall to resist migration from the influence of the
lumen flow, e.g., blood, air, bile, etc.
[0045] An exemplary occlusion system comprising a continuous
embolic coil that is "cut to length" at the end of its deployment
into the target vessel or aneurysmal space is disclosed herein. An
exemplary delivery device for the continuous embolic coil that
provides such a "cut to length" feature is also disclosed. A
continuous embolic coil presents several advantages to the
clinician. For example, a typical embolic coil occlusion requires
several coils to complete. Before deployment, a clinician must
estimate the number and length of coils that will be inserted into
the target. The typical discrete length coils may result in the
physician misjudging the final coil size such that if a coil that
is too short, another discrete coil must be used or, if the final
chosen coil is too long, the physician is required to retract the
final coil, discard it, and replace it with a shorter coil.
Further, the individual coils are deployed one at a time. The
clinician is required to sequentially reload the coils until a
desired coil pack is achieved.
[0046] In contrast, a single, continuous coil as disclosed herein
requires only a single loading step and may be "cut to length" by a
cutting element associated with, or independent from, the delivery
device, as discussed in more detail below. The single continuous
coil also limits the need to open additional packages of coils due
to underestimating the size of coil needed for the application or
due to retraction and discarding of the coils because the chosen
coils were too long for the application.
[0047] Reference is first made to FIGS. 1A-2D which illustrate some
features of the delivery device with a cutting element and some
features of the continuous embolic coil. As can be understood from
FIGS. 1A-1C, in one embodiment, an occlusion system 5 may include
an occlusion device 10, and a delivery device 15. In one
embodiment, the occlusion device 10 is a continuous embolic coil 10
of any flexible, biocompatible material. In one embodiment, the
continuous embolic coil 10 is a polymer continuous coil. Polymer
coils may provide an advantage over other materials in safely
cutting their length intraoperatively. In one embodiment, the
continuous embolic coil 10 is a shape memory polymer continuous
coil. In one embodiment, the continuous embolic coil 10 is a
radiopaque polymer coil, such as a coil described in
PCT/US11/046829, filed Aug. 8, 2011 and entitled Radiopaque Shape
Memory Polymers for Medical Devices. The coil 10 is manufactured in
many diameter sizes and shapes to accommodate various target
vessels. The polymer coil 10 may be formed with a non-round
cross-section which is unique when compared to metal coils that are
formed from typical wire-forming processes (e.g., drawn and
rolled). Unique cross sections can provide significant advantages
to the ability of the polymer coil to fill an aneurysm space or
provide stability in position thereby resisting migration due to
blood flow, etc. For example, cross sections of the coil 10 may
include star-shaped (FIG. 2A), crescent-shaped (FIG. 2B), rounded
square (FIG. 2C), or round (FIG. 2D). The exemplary cross-sections
of the coil 10 are shown within the delivery device 15. In some
embodiments, the effective diameter D of the coil ranges from about
0.007'' to about 0.035'' in diameter. Such diameters generally
correspond to standardized metal coil diameters and common delivery
catheter internal diameter sizes.
[0048] In one exemplary implementation, the radiopaque polymer coil
10 is manufactured as a unique composite structure, where a second
polymer is placed internal to a first polymer forming the bulk of
the coil 10 during casting or molding of the polymer coil 10. The
second polymer strand may provide several key advantages to the
polymer coil 10 including the following: increased stiffness to
provide greater radial force at deployment for better anchoring;
improved resistance to buckling which assists delivery down a small
delivery catheter placed in a tortuous path; and improved strength
for retraction back into the delivery catheter if/as needed during
deployment in order to modify the placement of the coils, or
entirely remove it from the vasculature. Conversely, without the
strand, the polymer coil 10 can be very soft and compliant for
great compaction and achievement of very high packing factors.
Advantageously, fabrication costs of the radiopaque polymer coil 10
are generally low. Either configuration may be trimmed or cut
mechanically. A soft polymer coil, e.g. a shape memory polymer coil
or a radiopaque shape memory polymer coil, provides an additional
advantage over metal coils. When a metal coil is cut, it will
likely have a sharp, uneven edge that can cause injury or
perforation to the target vessel, occlusion site, aneurysmal space
or surrounding tissue. Advantageously, when a soft polymer coil is
cut or trimmed, it has a benign edge and has little to no risk of
causing injury or perforation to the target vessel, occlusion site,
aneurysmal space or surrounding tissue.
[0049] The radiopaque shape memory polymer coil 10 may be made with
an inherent curl shape to help target how it will deploy and
develop a highly dense coil pack in limited anatomical geometry at
a core body temperature which exceeds the material's Tg. Coil forms
(curl shapes) may be fabricated from multiple shapes including, but
not limited to, helical, tornado or tapered diameters,
three-dimensional framing shapes, two dimensional omega- or
D-shapes, or straight (linear shapes). The radiopaque polymer coil
10 may be made from a thermoset, cross-linked shape memory polymer
that assures that a curled coil shape can be temporarily
straightened to place the long coil on a reel or dispensing device
(see discussion below) and to transfer the coil 10 through a single
delivery catheter lumen, and yet, have high confidence in the coil
10 curling when deployed into the vessel to help form a dense coil
pack. In one embodiment, this temporary form may use the shape
memory polymer's temporary storage shape (e.g., straight) that
returns to a curled shape when the temperature is increased above
the material's Tg. Curl diameters can be fabricated across a large
spectrum of dimensions including, but not limited to, approximately
2 mm to approximately 25 mm curl diameters.
[0050] Returning now to FIGS. 1A-1D, the delivery device 15 of the
occlusion system 5 includes at least one tubular delivery body 20,
55, such as a catheter, cannula or delivery sheath 20, 55 and an
advance/retract mechanism 25 or other mechanism for pushing the
continuous embolic coil 10 out of the tubular delivery body 20, 55
and into the target occlusion site 30. In some embodiments, the
delivery device 15 includes an advance/retract mechanism 25 such as
a coil-loaded dispenser 35 which may be associated with or include
additional features that act or serve as a mechanism to advance the
coil 10 into the target occlusion site (such as the coil loaded
dispenser 35, see e.g. the reel or bobbin 35 of FIG. 1A, or thumb
wheel, see, e.g., the thumb wheel 40 described with respect to
FIGS. 5A and 9). In other embodiments, the advance/retract
mechanism 25 may be the hand of the surgeon or other practitioner
in the surgical suite, such that the coil 10 may be advanced
manually (such as by grasping or pushing by hand, see e.g., FIGS.
1C and 1D).
[0051] FIG. 1A depicts a first end 15b of the delivery device 15
and includes a coil-loaded dispenser 35. The coil loaded dispenser
35 may be a bobbin or reel upon which the continuous coil 10 is
disposed or wound upon. The coil 10 is received on the bobbin or
reel and held on the bobbin/reel until deployment. FIG. 1B
illustrates a first end 15b of the delivery device 15 and depicts a
second embodiment of a coil loaded dispenser 35 wherein a coil
shaped channel 36 configured to receive the straightened polymer
coil 10 is visible (an outer covering is hidden for clarity). The
coil shaped channel 36 is positioned in the coil loaded dispenser
35 and the coil 10 is received in the channel 36 and held within
the channel until deployment. The coil loaded dispenser 35 may
further include an opening 36a through which the coil 10 may be
deployed out of the coil dispenser 35.
[0052] FIG. 1C depicts another embodiment of the first end 15b of
the delivery device 15. As can be understood from FIG. 1C, a
tubular holding body 12, such as a guidewire or pusher holder tube
12, is maintained in a sterile packaging (not shown) and is
configured to hold the straightened coil 10 until deployment. In
order to keep the coil 10 in a straighter position in the tube 10,
the coil 10 may be manufactured to have less curl shape to it. That
is, a coil having shape memory polymer/shape change properties to
maintain the straighter (i.e. not curled) shape in the package form
may be used in this embodiment. FIG. 1C also depicts the needle
tube/hub introducer 37 configured to receive the coil 10 and
configured to couple or attach to the catheter 20 to load the coil
10 into the catheter or delivery sheath 20 for delivery to the
target occlusion site 30. FIG. 1D illustrates portions of the first
end 15b and the second end 15a of the delivery device 15. As can be
understood from FIG. 1 D, the needle tube/hub introducer 37 is
received in the catheter introducer 22, thereby providing a conduit
from the tubular holding body 12 to the delivery catheter 20 for
the coil 10. The tubular holding body 12 may further include a
window 12a or other advancement opening 12a through which a surgeon
can access the coil 10 and manually advance the coil 10 from the
tubular holding body 12 into the catheter introducer 22. That is,
the advance/retract mechanism 25 is the surgeons hand. More
specifically, the physician may grasp the continuous coil 10
directly with a gloved hand to either advance or retract the
continuous coil 10 and eliminate the need for a separate pusher or
wheel for this advancement or retraction function. The catheter
introducer 22 may include one or more Y-connectors 23 which serve
as tool access points, for example, for injection of a contrast
agent to allow the physician to confirm placement and adequacy of
the resulting coil pack.
[0053] FIG. 1E depicts a coil dispenser 35, which may be or include
a tubular holding body 12, which is configured to receive a coil 10
and hold the coil 10 in a pre-deployed state until deployment. FIG.
1E illustrates manual advancement of the coil 10 from the coil
dispenser 35 or tubular holding body 12 into the catheter
introducer 22. In this embodiment, the advance/retract mechanism 25
is the surgeon's hand and the surgeon may grasp the continuous coil
10 directly with a gloved hand to either advance or retract the
continuous coil 10 and eliminate the need for a separate pusher or
wheel for this advancement or retraction function. The needle
tube/hub introducer 37 depicted is configured to receive the coil
10 and is configured to couple or attach to the catheter 20 to load
the coil 10 into the catheter or delivery sheath 20 for delivery to
the target occlusion site 30. The target occlusion site 30 may be a
vessel 30a (FIG. 1F) or the space, void or cavity 30c created
between an abdominal aortic aneurysm endograft device 30d (FIG. 1G)
and the bulging aortic wall. In an embodiment where the target site
is the void 30c between an abdominal aortic aneurysm endograft
device 30d and the vessel wall, access may be through a needle
stick or cannula entering through the patient's back, adjacent to
the spinal column and into the aorta. Generally, access is not
through a vessel. While a catheter could be used with the
guidewire, it may be preferable to use a cannula or trocar to
provide more structure for this type of access point. In either
case, the continuous coil 10 fills the void 30c around the
endograft 30d and is then cut outside the patient's body with
sterile scissors or a scalpel as described below. The remaining
coil 10 in the cannula 20 is simply pushed into the space 30c via a
separate guidewire.
[0054] The surgeon may visualize the coil 10 by fluoroscopy or
other non-invasive imaging technique (e.g., magnetic resonance or
CT) or a combination thereof, to determine whether the space has
been partially or completely filled. In some embodiments, after it
is determined that enough coil 10 has been advanced (i.e. the
surgeon determines the desired or needed length), the surgeon can
cut the coil with, for example, a scalpel, scissors or other device
with a blade, at the proximal end of the catheter 37a. A separate
guidewire (not shown) is used to push the remaining coil into the
target location (occlusion site or aneurysmal space). In some
embodiments, the coil may be cut at the distal end. In some
embodiments, a cutting mechanism 45 associated with the delivery
device 15 and described herein is used to cut the coil 10 once
enough coil has been advanced into the catheter 20, occlusion site,
or aneurysmal space (i.e., when sufficient coil pack has been
achieved).
[0055] In some embodiments, the polymer coil 10 is manufactured
such that a large quantity of the polymer coil 10 is held in a
dispenser 35, such as, for example, a bobbin or reel, and the coil
is dispensed from the reel in any length. The coil-loaded dispenser
35 eliminates the need for multiple metal occlusion devices because
a single polymer occlusion device can be used to service the entire
procedure. In addition, one coil-loaded dispenser 35, or reel, may
be used to dispense coil lengths for packing at multiple locations
in a single patient, provided that the coil is cut between
locations, thereby eliminating the need to open separate duplicate
packages of coils or coil packages of different lengths during the
procedure. For example, this benefit can be specifically realized
when coiling gonadal veins to treat varicoceles or for treating
chronic pelvic congestion. Both of these procedures require coils
to be placed at multiple locations along a single vessel or vessel
trunk which may be easily accomplished by using the continuous
occlusion system (or aspects of the occlusion system) disclosed
herein. In some embodiments, the coil is advanced from the
dispenser by hand into the proximal end of a delivery device. In
some embodiments, the coil is cut at the proximal end of a delivery
device, by scissors, or scalpel or separate blade with the
remaining coil advanced forward through the delivery device by a
separate guidewire to complete the delivery.
[0056] In some embodiments, the coil-loaded dispenser or reel 35 is
the mechanism by which the coil is advanced or retracted as deemed
appropriate by the physician. In some embodiments, the coil may be
provided in various lengths e.g., 20 cm, 50 cm, 100 cm, 150 cm or
more. The coil 10 may have variable stiffness along its length and
may have a diameter of from approximately 0.010'' to approximately
0.035/0.038''. The coil 10 may be manufactured to have any
appropriate cross-section (see e.g., FIGS. 2A-2D) and may include
nylon fibers on a portion of or along the entire length of the coil
10 in order to aid in thrombus formation where advantageous and
appropriate. In some embodiments, the coil-loaded dispenser 35 may
also include an integrated or separate mechanism or feature for
controlling or actuating the coil under slippery or wet conditions
commonly found within the sterile field of catheterization
procedures. In one exemplary embodiment, the actuation feature 40
may be a simple friction wheel or other mechanical dispenser that
moves the coil into the delivery catheter or withdraws the coil
from the delivery catheter without the direct physician/glove
contact on the coil. (See, e.g., FIGS. 5A and 9) For certain
procedures, such as hemorrhage from trauma and filling of
aneurysms, there are medical advantages to allowing for a larger
volume of coil to be moved quickly in or out of the delivery
catheter. Conversely, for other procedures, such as neurovascular
aneurysm repair, there are medical advantages to allowing for very
slow, precise movement of the coil into or out of the catheter. The
slow or fast deployment of the coils could affect how and what type
of coil pack is achieved in the target occlusion site.
[0057] In some embodiments, the coil dispenser 35 may also include
or be coupled to a device 44 that provides a display 44a that
indicates the amount of coil 10 that has been dispensed from the
reel (See, e.g., FIGS. 5A and 9).
[0058] Reference is now made to FIGS. 3A-9 for a discussion of a
"cut to length" feature or cutting mechanism 45 which may be
associated with the second end 15a of the delivery device 15 which
includes the tubular delivery body 20, 55, such as a delivery
catheter or sheath 20 or cannula 55, of the occlusion system 5. In
some embodiments, the cut to length feature or cutting mechanism 45
is located at the distal end of the tubular delivery body 20, 55.
In some embodiments, the cut to length feature or cutting mechanism
45 is located at the proximal end of the tubular delivery body 20,
55.
[0059] In some embodiments, the system 5 includes a device or
feature 45 that provides the ability to intraoperatively trim or
cut the polymer coil 10, such as a radiopaque polymer coil 10 to a
desired length. Current coils are fabricated in short, independent,
discrete lengths that require the physician to estimate the length
and quantity of coils that will be needed to occlude the target
vessel. Advantageously, the polymer coil or occlusion device 10
described herein requires no such estimation. The currently
available short, discrete-length coils often results in the
physician misjudging the final coil size--either too short, which
requires yet another discrete coil, or too long, which requires
that the final coil to be retracted, discarded, and replaced with a
shorter coil.
[0060] The polymer coil described herein results in a discretionary
length of coil having any dimension less than or up to the total
length of the material applied to the bobbin/reel. As coil
deployment nears its endpoint during the procedure, the physician
can carefully deploy "just the right amount" before determining the
point at which to cut the coil and end the deployment. Accordingly,
the need for opening additional packages due to undersizing coils
or retracting and discarding coils that were found to be too long
to fit is reduced or eliminated. This flexibility provides for a
more predictable and repeatable application of embolic coils for
occlusion of a target vessel.
[0061] As illustrated in FIGS. 3A-8, in some embodiments, the cut
to length feature or cutting mechanism 45 is located at the distal
end of the first tubular delivery body 20, such as an outer
catheter or sheath 20 and/or at the distal end of the second
tubular delivery body 55, such as an inner cannula 55. As shown,
the second end 15a of the delivery device 15 comprises a first
tubular delivery body 20 (such as an outer catheter sheath 20
and/or a second tubular delivery body 55, such as an inner cannula
55, that incorporates a mechanical cutting mechanism for trimming
the polymer coil 10, such as a radiopaque polymer coil (with or
without an internal strand) at that end of the tubular delivery
body 20, 55. In some embodiments, the cutting mechanism 45 can be
used repeatedly without removing and manually reloading the tubular
delivery body between uses.
[0062] As shown in FIGS. 3A and 3B, in one embodiment, the second
end 15a of the delivery device 15 comprises an inner cannula 55 or
second tubular delivery body 55 coupled to an inner hub 55a and an
outer catheter or sheath 20 or first tubular delivery body 20
coupled to an outer hub 20a. In some embodiments, the inner tubular
delivery body 55 may be a cannula 55 and the outer tubular delivery
body 20 may be a delivery sheath 20. Each of the distal end 51 of
the outer sheath or catheter 20 and the distal end 56 of the inner
cannula 55 includes a cutting feature 45, such as a mechanical
blade or a sharp, defined edge. The hubs 20a, 55a extend outside of
the patient where a surgeon may grasp them and rotate them to cut
the coil 10. As shown in FIG. 3B, the inner tubular body 55 is
coaxial with the outer tubular body 20 and the bodies 20, 55 are
configured to rotate in opposite directions relative to each other
in order to cut the continuous coil 10. That is, the physician
rotates the outer tubular body 20 via the outer hub 20a
independently of the rotation of the inner tubular body 55 via the
inner hub 55a. The distal end 56 of the inner tubular body 55
defines an aperture 57, which may be off-set from the center of the
inner or second tubular delivery body 55. The distal end 51 of the
outer tubular body 20 defines an aperture 58, which may be off-set
from the center of the outer or first tubular delivery body 20.
[0063] In use, the continuous embolic coil 10 is loaded into the
first tubular delivery body 20 and the second tubular delivery body
55 at the second end 15a of the delivery device 15 in a
non-expanded (or pre-deployed or storage) state, e.g., via the
needle tube/hub introducer 37 coupled thereto that is configured to
receive the coil 10 from, for example, the coil dispenser 35. Once
the surgeon has placed the tubular delivery bodies 20, 55 into the
proper location, the continuous embolic coil 10 may be delivered by
an advance/retract mechanism 25 out of the tubular delivery bodies
20, 55. The straightened continuous coil 10 (in a non-expanded
state) is deployed by advancing it down the tubular delivery body
20, 55, using an advance/retract mechanism 25 to deliver it out of
the distal ends of the of the tubular delivery bodies 20, 55 at the
target occlusion site 30. Once the surgeon determines that a
desired amount of coil 10 has been delivered to the target site 30,
the surgeon can engage the cutting features 45. As the coil 10
emanates from the inner tubular body 55 that is coaxial with the
outer tubular body 20 through the holes or apertures 58, 57 at the
respective distal ends 56, 51 that are offset from the center of
both the inner and outer tubular bodies 20, 55 (see FIGS. 3C and
3D), the outer tubular body 20 is rotated with respect to the inner
tubular body 55, thereby causing the two openings 58, 57 to cross
(see FIG. 3E). The sharp, defined edge 45 on each opening 58, 57,
act like scissor blades and cut the polymer coil 10. The outer
tubular body 20 is rotated back into its original position (see
FIG. 3D), thereby aligning the openings 57, 58 to allow for the
unobstructed, continued delivery of the coil 10 between cuts. The
coil 10 may continue to be delivered to the target site or to a
second target site, as desired.
[0064] As shown in the distal end cross-section in FIG. 4, in
another exemplary embodiment, the delivery device 15 includes a
first tubular delivery body 20, such as a catheter 20, and a second
tubular delivery body 55, such as a cannula 55. The second tubular
delivery body 55 may fit within the first tubular delivery body 20
and may be positioned in a void or hollow space 75 defined in the
first tubular delivery body 20 by the continuous coil 10. As shown
in FIG. 4, due to the cross-section of the continuous coil 10 (see,
e.g., FIGS. 2A-2D), a void or hollow space 75 may be defined
between the coil 10 and the first tubular delivery body or catheter
20. The second tubular delivery body or cannula 55 may be
positioned within the void 75 such that the cutting mechanism 45 is
positioned over or about the coil 10. The second tubular delivery
body or cannula 55 includes a cutting mechanism 45, such as a blade
or sharp edge disposed at a distal end thereof and an actuator
extending within the second tubular delivery body 55 from the
proximal end to the distal end, such as an actuation wire 81 (not
shown), that is coupled to the cutting mechanism 45 to actuate the
cutting mechanism 45 to cut the coil 10.
[0065] In use, the second tubular body or cannula 55 with a cutting
feature 45 is co-loaded with the occlusion device or continuous
embolic coil 10 into the first tubular delivery body 20 at the
second end 15a of the delivery device 15 in a non-expanded (or
pre-deployed or storage) state, e.g., via the needle tube/hub
introducer 37 coupled thereto that is configured to receive the
coil 10 from, for example, the coil dispenser 35. Once the surgeon
has placed the first tubular delivery body 20 into the proper
location, the occlusion device or continuous embolic coil 10 may be
delivered by an advance/retract mechanism 25 out of the first
tubular delivery body 20. The straightened continuous coil 10 (in a
non-expanded state) is deployed by advancing it down the tubular
delivery body 20, using an advance/retract mechanism 25, to deliver
it out the distal end of the first tubular delivery body 20 at the
target occlusion site 30. Once the surgeon determines that a
desired amount of coil 10 has been delivered to the target site 30,
the surgeon can actuate the second tubular delivery body 55. The
surgeon pulls the actuation wire 81 to engage the cutting feature
45, thereby cutting the coil 10. After the coil 10 is cut, the
cutting feature 45 is disengaged from the coil 10 by releasing the
actuation wire 81. The second tubular delivery body 55 can be
withdrawn from the first tubular delivery body 20 or remain in
place and the coil 10 can continue to be delivered, unobstructed,
to the target site or to a second target site, as desired.
[0066] As can be understood from FIGS. 5A-7, in some embodiments,
the cutting mechanism 45 may be a wire garrote 46. As shown in FIG.
5A, the first end 15b of the delivery device 15 includes a coil
dispenser 35 coupled to a second end 15a of the delivery device
that includes a first tubular delivery body 20, such as a delivery
catheter or sheath 20, via a catheter/sheath hub 23. The delivery
device 15 may include a mechanical advance/retract mechanism 25,
such as an actuation mechanism 40, such as a thumb wheel, to
advance and retract the coil 10. In other embodiments, and with
reference to FIGS. 1C and 1D, the first end 15b of the delivery
device 15 may include a manual advance/retract mechanism 25. The
delivery device 15 may also include a wire actuation mechanism 80
coupled to one or more wires 81 that are associated with each other
to make a cutting mechanism 45, such as a wire garrote 46. In some
embodiments, the wires 81 are made of nitinol, stainless steel or
other appropriate thin wire. The wire or wires 81 are disposed
axially along the length of the first tubular delivery body 20 from
the distal end 87 back to the proximal hub 23. At the proximal hub
23, there is a wire actuation mechanism 80 that permits the
physician to pull the wire 81 thereby causing the distal end of the
garrote 46 to tighten around the polymer coil 10 and subsequently
cut through it.
[0067] In one embodiment, and as can be understood from FIG. 5B,
the wire garrote 46 is comprised of a single wire 81. The single
wire 81 extends from the distal end of the first tubular delivery
body 20 and encircles the coil 10. The free ends 81a of the wire 81
are coupled to the wire actuation mechanism 80. When the wire
actuation mechanism 80 is actuated (e.g., pulled), the free ends
81a transition from a relaxed state into a non-relaxed stated
(e.g., they are pulled taut) and the portion of the wire 81
encircling the coil 10 tightens or closes around the coil 10,
thereby cutting the coil 10. Once cut, the wire actuation mechanism
80 is released, the free ends 81a transition back to a relaxed
state and the portion of the wire 81 encircling the coil 10 loosens
or relaxes around the coil 10 such that coil delivery can continue
unobstructed by the wire garrote 46.
[0068] In another exemplary embodiment, and as can be understood
from FIG. 5C, the wire garrote 46 is comprised of at least two
wires 81. The wires 81 extend from the distal end of the first
tubular delivery body 20 and encircle the coil 10. The free ends
81a of the wires 81 are coupled to the wire actuation mechanism 80.
When the wire actuation mechanism 80 is actuated (e.g., pulled),
the free ends 81a transition from a relaxed state into a
non-relaxed state (e.g., they are pulled taut) and the portion of
the wires 81 encircling the coil 10 tighten or close around the
coil 10, thereby cutting the coil 10. Once cut, the wire actuation
mechanism 80 is released, the free ends 81a transition back to a
relaxed state and the portion of the wires 81 encircling the coil
10 loosen or relax around the coil 10 such that coil delivery can
continue unobstructed by the wire garrote 46.
[0069] In another embodiment, and as can be understood from FIGS.
6A through 6F, instead of being positioned in the first tubular
delivery body or catheter 20, the wire garrote 46 is positioned in
a second tubular delivery body 55, such as a cannula 55, that
passes through the first tubular delivery body 20 of the delivery
device 15 as described above with respect to FIG. 5A. The second
tubular delivery body 55 includes one or more smaller tubular
bodies or conduits 90 disposed axially along the length of the
second tubular body 55. The conduit(s) 90 define a lumen configured
to receive the wire 81. In one embodiment, as shown in FIG. 6A, the
distal end 92 of the conduit 90 may include a hypotube tip 93 and
may optionally include and be coupled to a ring body 94 (see FIG.
6B) by any appropriate means, such as welding or an adhesive. In
other embodiments, the cannula 55 does not include a ring body 94.
The hypotube tip 93 provides structural support to the tip of the
tubular body 55 and if included, together with the ring body 94,
provides a structure to hold the wire 81 in position and when
actuated, prevents the wire 81 from shredding the first tubular
delivery body 20 because the wire 81 only engages with the coil 10
and does not engage with the first tubular delivery body 20. In
some embodiments, and as indicated in FIG. 6B, the distal end 92 of
the conduit 90 does not include a hypotube tip 93. A ring body 94
is positioned at a distal end of the cannula 55, and a distal end
81b of the wire 81 is coupled to the ring body 94 by any
appropriate means, such as welding or an adhesive. As such, only a
single wire 81 comes back to the proximal end of the first end 15b
of the delivery device 15. The wire 81 maintains its shape around
the ring body 93 based on the shape memory characteristics of the
wire 81. The ring body 94 provides structural support to the tip of
the tubular body 55 and provides a structure to hold the wire 81 in
position and when actuated, prevents the wire 81 from shredding the
first tubular delivery body 20 because the conduits 90 do not
collapse and the wire 81 only engages with the coil 10 and does not
engage with the first tubular delivery body 20.
[0070] In one embodiment, the inner diameter of the first tubular
delivery body 20 is 0.055'', the outer diameter of the second
tubular delivery body 55 is 0.053'' and the inner diameter of the
second tubular delivery body 55 is 0.036''. In some embodiments,
the second tubular body 55 or cannula 55 may be a double wall
cannula having a diameter of 0.017'' or a single wall cannula
having a diameter of 0.0085''. The wire 81 may be 0.001'' stainless
steel or nitinol wire having an outer diameter of 0.035''. The
smaller tubular bodies or conduits 90 may be PEEK tubes or PEEK
tubes with hypotube tips and, in some embodiments, have a diameter
of less than 0.0085''.
[0071] In use, the occlusion device or continuous embolic coil 10
is loaded into the first tubular delivery body 20 and the second
tubular delivery body 55 in a non-expanded (or pre-deployed or
storage) state, e.g., via the needle tube/hub introducer 37 coupled
thereto that is configured to receive the coil 10 from, for
example, the coil dispenser 35. The wire(s) 81 are threaded through
the conduits 90 before placement of the second tubular delivery
body 55 into the first tubular delivery body 20. While the loop of
wire 81 that defines the garrote 46 is formed around the ring body
94 (when it is included) prior to insertion, the coil 10 may
proceed through the delivery bodies 20, 55 unobstructed until the
wire actuation mechanism 80 is engaged. Where a ring body 94 is not
present, enough wire 81 is extended from the conduits 90 with
hypotube tips 93 such that a single loop (from a single wire 81) or
a double loop (from a double wire 81) (i.e. the garrote 46) is
formed through which the coil 10 can pass without obstructing
delivery of the coil 10. Once the surgeon has placed the tubular
delivery bodies 20, 55 into the proper location, the coil 10 may be
advanced by an advance/retract mechanism 25, such as an actuation
feature 40, out of the delivery bodies 20, 55. Once the surgeon
determines that a desired amount of coil has been delivered to the
target site, the surgeon engages the wire actuation mechanism 80 to
engage the garrote 46, which tightens around the polymer coil,
thereby cutting the coil 10 (see FIGS. 6C, 6D, 6E and 6F). FIGS. 6C
and 6D depict a garrote 46 having two wires 81 and FIGS. 6E and 6F
depict a garrote 46 having a single wire 81.
[0072] In one exemplary embodiment, and as can be understood from
FIG. 6C and 6, the wire garrote 46 is comprised of at least two
wires 81. The wires 81 extend from the distal end of the second
tubular delivery body 55 or cannula 55 and encircle the coil 10.
The free ends 81 a of the wires 81 are coupled to the wire
actuation mechanism 80. When the wire actuation mechanism 80 is
actuated (e.g., pulled in the direction indicated by the arrows),
the free ends 81a transition from a relaxed state into a
non-relaxed stated (e.g., they are pulled taut) and the portion of
the wires 81 encircling the coil 10 tighten or close around the
coil 10, thereby cutting the coil 10. Once cut, the wire actuation
mechanism 80 is released, the free ends 81a transition back to a
relaxed state and the portion of the wires 81 encircling the coil
10 loosen or relax around the coil 10 such that coil delivery can
continue unobstructed by the wire garrote 46 and the cutting wire
81 is positioned as it was before it was used to cut the coil 10.
In another embodiment, the cutting wire 81 is not repositioned back
to its relaxed state. Instead, the second delivery body 55 or
cannula 55 with wire(s) 81 is replaced after every cut. That is,
coil 10 and the used cannula 55 are withdrawn from the first
tubular delivery body 20 or catheter 20 and a new cannula 55 is
loaded into the catheter 20 and the continuous coil 10 is reloaded
into the first and second delivery bodies 20, 55. In another
embodiment, the wire(s) 81 and garrote 46 reset after cutting the
coil 10 without any physical intervention based on the shape memory
properties of nitinol. That is, because the wire(s) 81 are made of
nitinol, the wire(s) 81 transition back to a relaxed state
following the cut without physical intervention. In another
embodiment, the cutting wire 81 is reset or repositioned with a
mini-cannula (e.g. a smaller version of the cannula 55). In such an
embodiment, the coil 10, after being cut, is retracted from the
tubular delivery body(ies) 20, 55. A stiffer cannula having
approximately the same diameter as the coil 10 and having a tapered
distal end is advanced down the catheter 20 to contact the garrote
46 such that the garrote returns to its original (pre-cutting)
position. The stiffer cannula with a tapered end is withdrawn from
the catheter 20 and the coil 10 is advanced back down the catheter
20 to continue the coil delivery process.
[0073] In another exemplary embodiment, and as can be understood
from FIGS. 6E and 6F, the wire garrote 46 is comprised of a single
wire 81. The single wire 81 extends from the distal end of the
second tubular delivery body 55 or cannula 55 and encircles the
coil 10. The free ends 81a of the wire 81 are coupled to the wire
actuation mechanism 80. When the wire actuation mechanism 80 is
actuated (e.g., pulled in the direction indicated by the arrows),
the free ends 81a transition from a relaxed state into a
non-relaxed stated (e.g., they are pulled taut) and the portion of
the wire 81 encircling the coil 10 tightens or closes around the
coil 10, thereby cutting the coil 10. Once cut, the wire actuation
mechanism 80 is released, the free ends 81a transition back to a
relaxed state and the portion of the wire 81 encircling the coil 10
loosens or relaxes around the coil 10 such that coil delivery can
continue unobstructed by the wire garrote 46.
[0074] While FIGS. 6A through 6F describe embodiments related to a
second tubular delivery body 55 or cannula 55, it can be
appreciated that the first tubular delivery body 20 or catheter 20
may also have smaller tubular bodies or conduits 90 disposed
axially along the length of the delivery body 20 and configured to
receive the wire(s) 81.
[0075] As can be understood from FIG. 7, the first end 15b of the
delivery device 15 may be as described above with respect to FIG.
5A. The wire or wires 81 are ribbon-like and are disposed axially
along the length of the first tubular delivery body 20 in the wall
20a of the first tubular delivery body 20 or catheter 20 and back
to the proximal hub/end 23 of the second end 15a of the device 15.
At the proximal/hub end 23, the proximal ends 81a of the
ribbon-like wire 81 may act as a wire actuation mechanism 95 in
which the ends 81a are pull tabs 95a. The distal end 90 of the
ribbon like wire 81 defines an aperture 93 through which the coil
10 can pass unobstructed when the aperture 93 is in an open
configuration. The aperture 93 includes a cutting mechanism 45,
such as a sharp edge 91 to engage or enclose and tighten (e.g.,
like a guillotine) around the polymer coil 10 and subsequently cut
through it. More specifically, once the surgeon determines that a
desired amount of coil has been delivered to the target site, the
surgeon engages the pull tab 95a causing the aperture 93 of the
ribbon-like wire 81 to close around the coil 10, and specifically a
sharp edge 91 of the aperture 93, to engage or enclose and tighten
around the polymer coil 10, similar to how the wire garrote 46
described previously or a guillotine will close around a coil, and
subsequently cut through it. After the coil is cut, the cutting
mechanism 45 is disengaged from the coil 10 by releasing the pull
tabs 95a of the wire actuation mechanism 95. Push tab 95b may be
used to further release the wire 81 from about the coil 10 by
pushing the tab 95b to allow the aperture 93 to further release the
coil 10. The surgeon can continue to deploy the coil 10 into the
target occlusion site 30 unobstructed by the cutting mechanism 45
as desired. In some embodiments, a ring body 94 as described above
with respect to FIG. 6B, and others, may be used to provide
structure and support to the distal end of the catheter 20. In some
embodiments, rather than being disposed in a wall 20a of the
catheter 20, conduits 90 as described above but with a
cross-section that would complement the ribbon-like wire, may be
used to provide a conduit for the axial disposition of the
ribbon-like wire.
[0076] As can be understood from FIGS. 8A-8G, in one embodiment,
the delivery device 15 includes a delivery catheter or sheath 20, a
cutting mechanism 45 that includes an independent cutting strip,
knife or blade that is controlled by separate wires and a guide
track 100. As shown in FIGS. 8A-8C, the guide track 100 includes a
base 102 and at least one anchor post 115, and further defines a
plurality of lumens including a coil lumen 105 and at least one
cutting mechanism lumen or slot 110. The coil lumen 105 is
configured to receive the coil 10 and provides an exit path 125 for
the coil 10 from the proximal end through the distal end of the
catheter 20. The anchor post 115 is configured to anchor the guide
track 100 in the catheter 20.
[0077] The cutting mechanism lumen or slot 110 receives a cutting
mechanism 45 such as a cutting strip, knife, or blade. As
illustrated in FIGS. 8D-8F, in one embodiment, the cutting
mechanism is a double blade 120. The double blade 120 is formed
from a wire 123, such as nitinol or stainless steel. As indicated
in FIG. 8D, the wire 123 transitions from a round wire 121 into a
flattened wire 124 around a 180.degree. radius and is sharpened on
an inner diameter to create a cutting edge 122. As shown in FIG.
8E, the double blade 120, in a coil deployment state, defines an
opening through which the coil 10 can pass. As can be understood
from FIGS. 8E and 8G, and with reference to FIG. 8F, when it is
desired to cut the coil 10, the surgeon can engage the proximal
ends 123a of the wire 123, thereby pulling the cutting edges 122 of
the blades 120 together into a cutting or engagement state, as
indicated in FIG. 8E, to cut the coil 10.
[0078] In use, the occlusion device or continuous embolic coil 10
is loaded into a first tubular delivery body 20 in a non-expanded
(or pre-deployed or storage) state, e.g., via the needle tube/hub
introducer 37 coupled thereto and that is configured to receive the
coil 10 from, for example, the coil dispenser 35. Once the surgeon
has placed the first tubular delivery body 20 into the proper
location, the occlusion device or continuous embolic coil 10 may be
advanced by an advance/retract mechanism 25, such as actuation
feature 40, out of the delivery body 20. The straightened
continuous coil 10 (in non-expanded shape) is deployed by advancing
it down the delivery body 20, using an advance/retract mechanism
25, such as actuation feature 40, to deliver it out the distal end
of the first tubular delivery body 20 at the target occlusion site
30. Once the surgeon determines that a desired amount of coil 10
has been delivered to the target site, the surgeon can engage the
proximal ends 123a of the wire 123, thereby pulling the cutting
edges 122 of the blades 120 together, as indicated in FIG. 8E, to
cut the coil 10. After the coil is cut, the cutting mechanism 45 is
disengaged from the coil 10 by releasing the proximal ends 123a of
the wire 123 thereby transitioning the double blades 120 back into
a coil deployment state. The surgeon can continue to deploy the
coil 10 into the target occlusion site unobstructed by the cutting
mechanism 45 as desired.
[0079] As can be understood from FIG. 9, the cutting mechanism 45
may be positioned at a proximal end of the first tubular delivery
body 20. Such a location may be used when the resulting delivery
length is not critical to the application. A simpler mechanism can
be used that would cut the coil at the proximal end, allowing the
physician to simply push the cut end through the delivery catheter
with either the additional coil or a separate instrument such as a
guidewire. This allows for continued use of current delivery
catheters (a first tubular delivery body) without modification to
incorporate a cutting mechanism at the distal end. In one such
embodiment, the delivery device 15 includes a coil dispenser 35
coupled to a first tubular delivery body, such as a delivery
catheter or sheath 20 via a catheter/sheath hub 23. The device 15
may include an actuation mechanism 40, such as a thumb wheel, to
advance and retract the coil 10. A cutting mechanism 45 such as a
blade is positioned in or on the hub 23. The cutting mechanism 45
may be coupled to an actuator button or knob 100 having a safety
mechanism 102, such as a pre-cut release to prevent the blade from
engaging or cutting the coil 10 before actuation by the surgeon.
The safety mechanism 102 may be a knob, tab or button that is
rotated or pushed before the cutting mechanism 45 can be
actuated.
[0080] In use, the coil occlusion device 10 is loaded into the
first tubular delivery body 20 of the delivery device 15 in a
non-expanded (or pre-deployed or storage) state, e.g., via the
needle tube/hub introducer 37 coupled thereto and that is
configured to receive the coil 10 from, for example, the coil
dispenser 35. Once the surgeon has placed the first tubular
delivery body 20 into the proper location, the coil device 10 may
be advanced by an advance/retract mechanism 25, such as actuation
feature 40, out of the delivery body 20. The straightened
continuous coil 10 (in a non-expanded state) is deployed by
advancing it down the first tubular delivery body 20, using a an
advance/retract mechanism 25, such as actuation feature 40, to
deliver it out the distal end of the first tubular delivery body 20
at the target occlusion site 30. Once the surgeon determines that a
desired amount of coil 10 has been delivered to the target site,
the surgeon can unlock, release or rotate the safety mechanism 102
(as appropriate), engage (press down on) the actuator button 100 to
depress the blade 45 into the coil 10 and cut the coil 10 at the
proximal hub 23. Once the coil has been cut, the surgeon can
release the actuator button 100, thereby releasing the blade 45
from the coil 10 and the blade 45 and button 100 return to their
locked position, thereby allowing unrestrained continued coil 10
delivery as desired.
[0081] As can be understood from the previous discussion, the "cut
to length" feature 45 is at least partially enabled by the
described radiopaque polymer coil technology. A clear,
non-radiopaque polymer material would not be visible under
fluoroscopy or x-ray and subsequently, a physician would not be
able to discern the location/position of the coil in order to
determine when/where to trim its length. A metal coil would
represent significant challenges in designing a robust cutting
mechanism to assure the ends of the coil were clearly cut without
entanglement that could cause potential patient harm if not severed
completely. Likewise, delivery of continuous metal coil would
present some significant challenges to assure that a sharp edge is
not left on the coil that might subsequently cause tissue trauma or
damage to the vessel by either end of the cut coil. Finally, a
polymer coil with an internal reinforcing strand wherein both are
cut to separate the coil assures that no particulate or coil
fragments will be generated during the cutting or segmenting of the
coil in situ which could cause risk of an unintended embolus.
[0082] FIG. 10 illustrates one embodiment of a method of using a
delivery device configured to deliver a single continuous embolic
coil. In use, and in accordance with the exemplary method 200, in
operation 202, the occlusion device or continuous embolic coil 10
(e.g., the single continuous embolic coil) is loaded into a first
tubular delivery body 20, such as a catheter, extending from the
delivery body 20 in a non-expanded (or pre-deployed or storage)
state. It can be appreciated that in some embodiments, there may
also be a second tubular delivery body that is utilized with the
first tubular delivery body as disclosed elsewhere herein. Once the
surgeon has placed the first tubular delivery body 15 into the
proper location, and in accordance with operation 204, the coil
device 10 may be advanced by an advance/retract mechanism 25, such
as an actuation mechanism 40, out of the tubular body 20. The
straightened coil member 10 (in a non-expanded state) is deployed
by advancing the coil 10 down the first tubular delivery body 20,
using an advance/retract mechanism 25, such as an actuation feature
40, to deliver it out the distal end of the delivery body 20 at the
target occlusion site 30. In operation 204, the surgeon then
determines whether the coil pack is sufficient. In one embodiment,
this determination is made by monitoring the position of the coil
occlusion device 10 on a fluoroscope monitor or other clinical
medical imaging system in which the coil 10 may be seen. If the
coil pack is not sufficient, then the surgeon can continue to
deploy the coil 10 (back to operation 204). If the coil pack is
sufficient, and in accordance with operation 208, the surgeon can
deploy or actuate a cutting mechanism 45, such as a cutting
mechanism described herein, to cut the coil occlusion device 10.
The cutting mechanism 45 may be positioned at a distal end of the
first tubular delivery body 20 or at a proximal end of the first
tubular delivery body 20. In accordance with operation 210, once
cut, the surgeon can disengage the cutting mechanism 45 from the
coil occlusion device 10. Optionally, and in accordance with
operation 212, the surgeon may continue to deploy the coil 10 into
the first occlusion site as desired for precision filling.
Optionally, and in accordance with operation 214, the surgeon may
move the delivery device 15 (or a portion thereof) to another
target occlusion site for additional treatment without reloading
the device 15.
[0083] It should be appreciated that while the method 200 refers to
delivery of the coil 10 through the first tubular delivery body 20,
such as catheter 20, in accordance with some embodiments described
herein, a second tubular delivery body 55, such as a cannula 55,
may be coaxial with or otherwise positioned in the first tubular
delivery body 20. Accordingly, in some embodiments of the method
200, coil 10 may be deployed through both the first tubular
delivery body 20, such as catheter 20, and the second tubular
delivery body 55, such as cannula 55. It should be appreciated that
the operations of the method 200 may be performed in the order
illustrated, in another suitable order and/or one or more
operations may be performed simultaneously. Moreover, in some
embodiments, the method 200 may include more or fewer operations
than those illustrated.
[0084] Thus, as can be understood from the discussion found herein,
the delivery device and its various configurations as disclosed
herein address current key clinical deficiencies that are unmet
with existing delivery devices for multiple short or discrete
polymer coils and with other vascular occlusion devices, such as
metal mesh plugs, and the associated challenges discussed
herein.
[0085] All directional references (e.g., proximal, distal, upper,
lower, upward, downward, left, right, lateral, front, back, top,
bottom, above, below, vertical, horizontal, clockwise, and
counterclockwise) are only used for identification purposes to aid
the reader's understanding of the present invention, and do not
create limitations, particularly as to the position, orientation,
or use of the invention. Connection references (e.g., attached,
coupled, connected, and joined) are to be construed broadly and may
include intermediate members between a collection of elements and
relative movement between elements unless otherwise indicated. As
such, connection references do not necessarily infer that two
elements are directly connected and in fixed relation to each
other. It should be noted that delivery sheath and delivery
catheter may be used interchangeably for purposes of this
description. The exemplary drawings are for purposes of
illustration only and the dimensions, positions, order and relative
sizes reflected in the drawings attached hereto may vary.
[0086] The above specification, examples and data provide a
complete description of the structure and use of exemplary
embodiments of the invention as claimed below. Although various
embodiments of the invention as claimed have been described above
with a certain degree of particularity, or with reference to one or
more individual embodiments, those skilled in the art could make
numerous alterations to the disclosed embodiments without departing
from the spirit or scope of this invention. Other embodiments are
therefore contemplated. It is intended that all matter contained in
the above description and shown in the accompanying drawings shall
be interpreted as illustrative only of particular embodiments and
not limiting. Changes in detail or structure may be made without
departing from the basic elements of the invention as defined in
the following claims.
* * * * *