U.S. patent application number 15/847115 was filed with the patent office on 2018-04-19 for method and apparatus for deploying and retrieving objects in a cavity.
The applicant listed for this patent is ADIENT MEDICAL, INC.. Invention is credited to Jeremy DURACK, Mitchell EGGERS, David FRANKLIN, Michael HOGAN, Raymond KIRK, Joseph STEELE.
Application Number | 20180104042 15/847115 |
Document ID | / |
Family ID | 60203661 |
Filed Date | 2018-04-19 |
United States Patent
Application |
20180104042 |
Kind Code |
A1 |
EGGERS; Mitchell ; et
al. |
April 19, 2018 |
METHOD AND APPARATUS FOR DEPLOYING AND RETRIEVING OBJECTS IN A
CAVITY
Abstract
The present invention relates generally to a method and
apparatus for deploying and/or retrieving an object (e.g., a vena
cava filter) in a cavity (e.g., a vena cava) using a system
configured to: (i) maintain grip of the unsheathed object in the
cavity until deliberately released, (ii) prevent premature release
of the object in the cavity, and/or (iii) facilitate retrieval by
first everting said object, then withdrawing the object through a
guiding catheter (e.g., retrieval via eversion).
Inventors: |
EGGERS; Mitchell; (Pearland,
TX) ; DURACK; Jeremy; (Pearland, TX) ; STEELE;
Joseph; (Pearland, TX) ; HOGAN; Michael;
(Pearland, TX) ; KIRK; Raymond; (Pearland, TX)
; FRANKLIN; David; (Pearland, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ADIENT MEDICAL, INC. |
Pearland |
TX |
US |
|
|
Family ID: |
60203661 |
Appl. No.: |
15/847115 |
Filed: |
December 19, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15592043 |
May 10, 2017 |
9895215 |
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15847115 |
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15586210 |
May 3, 2017 |
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15592043 |
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62331291 |
May 3, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2/95 20130101; A61F
2002/016 20130101; A61F 2/011 20200501; A61F 2002/9505 20130101;
A61F 2230/0006 20130101; A61F 2002/9528 20130101; A61F 2/01
20130101; A61F 2230/0023 20130101; A61F 2230/0067 20130101 |
International
Class: |
A61F 2/01 20060101
A61F002/01; A61M 29/00 20060101 A61M029/00; A61M 25/10 20060101
A61M025/10 |
Claims
1. A system configured to deliver an object to, and retrieve the
object from, a location in a cavity, the system comprising: a
guiding catheter configured to provide a conduit to and from the
location for the object; object deployment components configured to
facilitate deployment of the object through the guiding catheter at
the location in the cavity; and a retention mechanism configured to
secure the object while the object is in the cavity, the retention
mechanism comprising: (i) an outer tube with distal fingers that
protrude distally through an opening in an end of the object; and
(ii) an inner rod or inner tube within the outer tube that prevents
the distal fingers on the outer tube from collapsing; wherein,
responsive to the inner rod or inner tube being withdrawn
proximally with respect to the outer tube, the distal fingers of
the outer tube collapse to facilitate withdrawal of the distal
fingers through the opening in the end of the object, and
withdrawal of the inner rod or inner tube and the outer tube from
the object, thereby releasing the object at the location within the
cavity.
2. The system of claim 1, wherein the object deployment components
comprise a balloon configured to expand the object at the
location.
3. The system of claim 2, further comprising an interlock mechanism
configured to prevent release of the object at the location in the
cavity before a target position of the object in the cavity is
achieved.
4. The system of claim 3, wherein actuation of the interlock
mechanism enables the release of the object by the retention
mechanism, thereby facilitating deployment of the object at the
location in the cavity.
5. The system of claim 3, wherein the interlock mechanism is
configured to prevent premature release of the object before the
object is balloon expanded to a predetermined pressure.
6. The system of claim 3, wherein the interlock mechanism
comprises: (i) a piston in a cylinder that is advanced through the
cylinder by balloon pressure; and (ii) a spring loaded trigger
operatively coupled to the piston configured to move responsive to
movement by the piston to disengage a release switch to facilitate
release of the object at the location in the cavity.
7. The system of claim 6, wherein the interlock mechanism further
comprises an orifice configured to conduct the balloon pressure to
the cylinder, the orifice having a diameter that is smaller than a
diameter of the cylinder.
8. The system of claim 7, wherein the spring loaded trigger
includes a body, a foot portion, and a leg portion extending
between the body and the foot portion; the foot portion operatively
coupled to the piston, the foot portion supported by a ledge and
configured to be pushed off the ledge by the piston and cause the
spring loaded trigger to disengage the release switch.
9. The system of claim 1, wherein, prior to release of the object
at the location in the cavity the retention mechanism enables a
user to pull proximally on the end of the object causing the object
to evert, and with continued pulling advance the object into the
guiding catheter for removal from the cavity.
10. The system of claim 1, wherein the cavity is the vena cava and
the object is a vena cava filter.
11. A system configured to retrieve an object from a location in a
cavity, the system comprising: a guiding catheter configured to
provide a conduit to and from the location for the object; and an
extraction device catheter comprising grasping and extraction
components for grasping and extracting the object, the extraction
device catheter configured such that the grasping and extraction
components are located at a distal end of the extraction device
catheter and actuator controls for the grasping and extraction
components are located at a proximal end of the extraction device
catheter.
12. The system of claim 11, wherein the extraction device catheter
is configured such that the actuator controls comprise a sliding
handle and thumb grip located at the proximal end of the extraction
device catheter configured to be compressed relative to each other
to cause the grasping and extraction components to grasp the object
and extend relative to each other to cause the grasping and
extraction components to release the object.
13. The system of claim 12, wherein the extraction device catheter
is advanced through the guiding catheter to the location of the
object and the grasping and extraction components grasp and secure
the object responsive to the sliding handle and thumb grip being
compressed relative to each other, which enables a user to pull
proximally on an end of the object causing the object to evert, and
with continued pulling advance the object into the guiding catheter
for removal from the cavity.
14. The system of claim 13, wherein the grasping and extraction
components comprise jaws configured to close around the end of the
object responsive to the sliding handle and thumb grip being
compressed relative to each other.
15. The system of claim 11, wherein the cavity is the vena cava and
the object is a vena cava filter.
16. A method for delivering an object to, and retrieving the object
from, a location in a cavity with a delivery system, the system
comprising a guiding catheter, object deployment components, and a
retention mechanism, the method comprising: forming, with the
guiding catheter, a conduit to and from the location for the
object; facilitating, with the object deployment components,
deployment of the object through the guiding catheter at the
location in the cavity; and securing, with the retention mechanism,
the object while the object is in the cavity, the retention
mechanism comprising: (i) an outer tube with distal fingers that
protrude distally through an opening in an end of the object; and
(ii) an inner rod or inner tube within the outer tube that prevents
the distal fingers on the outer tube from collapsing, wherein,
responsive to the inner rod or inner tube being withdrawn
proximally with respect to the outer tube, the distal fingers of
the outer tube collapse to facilitate withdrawal of the distal
fingers through the opening in the end of the object, and
withdrawal of the inner rod or inner tube and the outer tube from
the object, thereby releasing the object at the location within the
cavity.
17. The method of claim 16, wherein the object deployment
components comprise a balloon configured to expand the object at
the location, and the method further comprises deploying the object
with the balloon.
18. The method of claim 16, wherein the system further comprises an
interlock mechanism, and the method further comprises preventing,
with the interlock mechanism, release of the object at the location
in the cavity before a target position of the object in the cavity
is achieved.
19. The method of claim 18, wherein the method further comprises
receiving, with the interlock mechanism, actuation to enable the
release of the object by the retention mechanism, thereby
facilitating deployment of the object at the location in the
cavity.
20. The method of claim 18, further comprising preventing, with the
interlock mechanism, premature release of the object before the
object is balloon expanded to a predetermined pressure.
21. The method of claim 18, wherein the interlock mechanism
comprises: (i) a piston in a cylinder that is advanced through the
cylinder by balloon pressure; and (ii) a spring loaded trigger
operatively coupled to the piston configured to move responsive to
movement by the piston to disengage a release switch to facilitate
release of the object at the location in the cavity.
22. The method of claim 21, further comprising conducting, with an
orifice, the balloon pressure to the cylinder, the orifice having a
diameter that is smaller than a diameter of the cylinder.
23. The method of claim 22, wherein the spring loaded trigger
includes a body, a foot portion, and a leg portion extending
between the body and the foot portion; the foot portion operatively
coupled to the piston, the foot portion supported by a ledge and
configured to be pushed off the ledge by the piston and cause the
spring loaded trigger to disengage the release switch.
24. The method of claim 16, further comprising, prior to release of
the object at the location in the cavity before the target position
of the object in the cavity is achieved, enabling a user to pull
proximally on the end of the object causing the object to evert,
and with continued pulling advance the object into the guiding
catheter for removal from the cavity.
25. The method of claim 16, wherein the cavity is a vena cava,
wherein the object is a vena cava filter.
26. A method for retrieving an object from a location in a cavity
with a retrieval system, the system comprising a guiding catheter
and an extraction device catheter, the method comprising: grasping,
with the extraction device catheter, the object at the location in
the cavity, the extraction device catheter configured such that
grasping and extraction components are located at a distal end of
the extraction device catheter and actuator controls for the
grasping and extraction components are located at a proximal end of
the extraction device catheter; and enabling with the extraction
device catheter, a user to pull proximally on an end of the object
causing the object to evert, and with continued pulling advance the
object into the guiding catheter for removal from the cavity.
27. The method of claim 26, wherein the extraction device catheter
is configured such that the actuator controls comprise a sliding
handle and thumb grip located at the proximal end of the extraction
device catheter, and wherein the method further comprises
compressing the sliding handle and thumb grip relative to each
other to cause the grasping and extraction components to grasp the
object and extending the sliding handle and thumb grip relative to
each other to cause the grasping and extraction components to
release the object.
28. The method of claim 27, wherein the grasping and extraction
components comprise jaws configured to close around the end of the
object responsive to the sliding handle and thumb grip being
compressed relative to each other.
29. The method of claim 26, wherein the cavity is a vena cava,
wherein the object is a vena cava filter.
Description
RELATED PATENT APPLICATIONS
[0001] This application is a continuation application of U.S.
application Ser. No. 15/592,043 filed May 10, 2017, which is a
continuation application of U.S. application Ser. No. 15/586,210
filed May 3, 2017, which claims priority to U.S. Provisional
Application Ser. No. 62/331,291, filed May 3, 2016, all of which
are herein incorporated herein by reference in their
entireties.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a method and
apparatus for delivering and retrieving an object (e.g., a vena
cava filter) in a cavity.
BACKGROUND OF THE INVENTION
[0003] Between 100,000 to 300,000 Americans die annually from
pulmonary embolism (PE), which is more than breast cancer, AIDS,
and traffic fatalities combined. PE is the 3rd leading cause of
death in the United States. A similar incidence of PE is found in
Europe with approximately 370,000 annual deaths. Moreover, PE is
the third most common cause of death in trauma patients that
survive the first 24 hours. An estimated 25% of all hospitalized
patients have some form of deep vein thrombosis (DVT), which is
often clinically unapparent unless PE develops. On average, 33% of
DVT will progress to symptomatic PE, of which 10% will be
fatal.
[0004] Risk factors for PE arising from DVT follow Virchow's Triad:
(i) endothelial injury, (ii) hypercoaguability, and (iii)
hemodynamic changes (stasis or turbulence). Specific at risk
situations include hip and knee arthroplasty, abdominal, pelvic and
extremity surgeries, pelvic and long bone fractures, major spine
and brain trauma, prolonged immobility such as prolonged hospital
stays and air travel, paralysis, advanced age, prior DVT, cancer,
obesity, chronic obstructive pulmonary disease, diabetes,
congestive heart failure, and other situations. Patients undergoing
orthopedic procedures can carry a higher (e.g., 40-80%) risk for
DVT and PE following knee and hip surgeries in the absence of
prophylactic treatment, for example.
[0005] The American Academy of Orthopedic Surgeons (AAOS) has
issued guidelines for PE prophylaxis. According to the AAOS,
patients at standard risk of PE prophylaxis should be considered
for chemoprophylactic agents such as aspirin, low molecular weight
heparin (LMWH), synthetic pentassaccharides, or warfarin, in
addition to intra-operative and/or immediate postoperative
mechanical prophylaxis.
[0006] The duration of prophylaxis depends on the source of
potential DVT. Current recommendations for prophylaxis comprise a
minimum of seven to ten days for moderate to high risk surgeries
and up to 28-35 days for many orthopedic surgeries. Studies
indicate that hypercoaguability persists for at least one month
after injury in about 80% of trauma patients. Overall, prophylactic
treatment for possible venous thromboembolism (VTE), which is DVT
and PE combined, is often warranted for up to 35 days following
trauma or major surgery.
[0007] Contraindications for chemoprophylaxis include active
bleeding, hemorrhagic diathesis, hemorrhagic stroke, neurologic
surgery, extensive trauma, hemothorax, pelvic or lower extremity
fractures with intracranial bleeding, and anticoagulation
interruption.
[0008] For patients who are contraindicated for the above-mentioned
anti-coagulation prophylaxis, or where anti-coagulation therapy has
failed, the Society of Interventional Radiology, AAOS, American
College of Physicians, and the British Committee of Standards in
Haematology recommend the use of venous filters. These
intravascular blood filters are typically deployed via catheter
into the inferior vena cava (IVC) to catch emboli arising from
lower extremity DVT before reaching the heart or pulmonary arterial
circulation. Furthermore, the British Committee of Standards in
Hematology recommends IVC filter placement in pregnant patients who
have contraindications to anticoagulation and develop extensive VTE
shortly before delivery (e.g., within 2 weeks).
[0009] The Eastern Association for Surgery of Trauma further
recommends prophylactic IVC filters placed in trauma patients who
are at increased risk of bleeding and prolonged immobilization.
Such prophylactic recommendation follows studies that demonstrate a
low rate of PE in patients with severe polytrauma who underwent IVC
filter placement. A systematic study on the effectiveness of
prophylactic IVC filters in trauma patients revealed a consistent
reduction in PE with a relative risk of 0.20. Hence, in controlled
clinical studies, trauma patients are about five times more likely
to have a PE without an IVC filter. Moreover, analysis has revealed
that no fatal PEs occurred in the IVC filter arms of any of the
included studies, yet 20 fatal PEs occurred in the 407 patients not
receiving IVC filters.
[0010] Many IVC filters installed were expected to be permanent
fixtures since endothelialization usually occurs within 7-10 days,
making some models impractical to remove without irreversible
vascular damage, potentially leading to life threatening bleeding,
dissection of the IVC, and/or thrombosis. Although these permanent
filters have prevented PE, they have been shown to actually
increase the risk of recurrent DVT over time. For example, in one
randomized controlled trial the incidence of DVT within the IVC
filter cohort increased almost two times: (i) a 21% incidence of
recurrent DVT in the filter cohort vs. 12% in the non-filter cohort
at 2 years (p=0.02), and (ii) a 36% incidence of recurrent DVT in
the filter cohort versus 15% in the non-filter group at 8 years
(p=0.042). The filters did reduce the occurrence of PE. The filter
cohort experienced only 1% PE versus the non-filter cohort posting
5% PE in the first 12 days (p=0.03). Apparently the initial benefit
of reduced PE with permanent IVC filters is offset by an increase
in DVT.
[0011] In addition to increased incidence of DVT for prolonged IVC
filter deployment, filter occlusion has been reported with some
models at about a 6% to 30% occurrence, as well as filter migration
(about a 3% to 69% occurrence), venous insufficiency (about a 5% to
59% occurrence), and post thrombotic syndrome (about a 13% to 41%
occurrence). Complications from insertion including hematoma,
infection, pneumothorax, stroke, air embolism, misplacement, device
migration, vein perforation, arteriovenous fistula, and inadvertent
carotid artery puncture have an occurrence rate of about
4%-11%.
[0012] Retrievable IVC filters have been marketed more recently.
Retrievable IVC filters are intended to be removed when the
indication has expired, and hence circumvent many of the
deleterious complications of permanent filters such as increased
risk of DVT. The retrievable filters feature flexible hooks,
collapsing components, fewer barbed struts, unrestrained legs,
and/or other features to ease retrieval. Unfortunately, many of
these same features have led to unwanted side effects, including
filter migration, fatigue failure leading to fracture, IVC
penetration, fragment migration to hepatic veins and pulmonary
arteries, filter tilt, and metallic emboli, for example. In a
recent study perforation of the IVC by leading retrievable IVC
filters was shown to be the rule, not the exception, as about 86%
of the filters on computed tomography (CT) scans obtained between 1
and 880 days after filter placement had perforated the IVC. These
adverse events prompted the Food and Drug Administration (FDA) to
issue a formal communication stating that "FDA recommends that
implanting physicians and clinicians responsible for the ongoing
care of patients with retrievable IVC filters consider removing the
filter as soon as protection from PE is no longer needed."
Moreover, in 2014, a second communication released by the FDA
recommended that retrievable IVC filters be removed between 29 and
54 days after deployment for patients in whom the transient risk of
PE has passed. Even though these types of retrievable filters are
often intended to be removed within approximately 3 months, at
which time the technical retrieval success rate is 94% (versus 37%
at 12 months), several studies indicate that approximately 70%-80%
of patients with retrievable filters do not return to the hospital
for subsequent filter retrieval.
[0013] Due to the mounting complications of metallic retrievable
IVC filters following extended indwelling times, combined with the
reluctance of patients to return for IVC filter retrieval, fully
absorbable IVC filters have been proposed that obviate retrieval by
simply breaking down into carbon dioxide and water and/or other
materials several months following the risk period for PE.
Furthermore, these absorbable IVC filters are much more flexible
than conventional metal IVC filters rendering them less capable of
perforating the IVC and impaling neighboring organs.
SUMMARY OF THE INVENTION
[0014] The present invention relates generally to a method and
apparatus for deploying and retrieving an object (e.g., a vena cava
filter) in a cavity using a catheter configured to: (i) maintain
grip of the unsheathed object in the cavity until deliberately
released, (ii) prevent, using an interlock and/or other devices,
premature release of the object in the cavity, and/or (iii)
facilitate retrieval by first everting said object, then
withdrawing the object through a guiding catheter (e.g., retrieval
via eversion). In some embodiments, the present invention relates
to a method and apparatus for the deployment and retrieval of a
flexible vena cava filter. An example of such a filter is described
in U.S. patent application Ser. No. 13/403,790 entitled "Absorbable
Vascular Filter" filed Feb. 23, 2012, which is hereby incorporated
by reference in its entirety.
[0015] Most conventional IVC filters, when released from a
catheter, spring outward and are secured with metallic barbs at the
release site in the IVC, with no opportunity for repositioning.
Moreover, these prior art devices generally cannot be retrieved
without a separate retrieval system that often requires jugular
access. In typical retrieval methods, a catheter-based extraction
device secures the tip of the filter for cephalad retrieval through
a guiding catheter inserted in the jugular vein.
[0016] In contrast, the present invention enables the user to
maintain grip of an IVC filter, enabling repositioning of the
filter in the IVC following unsheathing of the filter, as well as
offering the option to retrieve the filter by everting and pulling
the filter in a proximal direction into the same catheter system
used during deployment (e.g., retrieval via eversion). This
retrieval technique is convenient, for example, if an IVC filter
deployed through the femoral vein has to be retrieved immediately
following deployment due to malposition and/or for other reasons,
since the same guiding catheter used to deploy the filter can be
used to retrieve the filter, thereby eliminating the need for
jugular access and/or additional components and/or equipment.
[0017] The disclosed IVC filter deployment and retrieval via
eversion method and apparatus is suitable for filters fabricated
from flexible materials such as absorbable filaments, polymers,
metal alloys, and/or other materials. In the event an absorbable
filter, for example, must be retrieved before it has been absorbed
in the IVC, the present invention enables efficient retrieval from
a position caudal to the filter and/or other positions. For
example, if an absorbable filter is catheter deployed from the
femoral vein into the IVC, it can be easily retrieved using the
present system by grasping and pulling the filter tip proximally,
or caudally causing the flexible filter to evert in the IVC, much
like pulling a sock inside out, and pulling the filter into the
guiding catheter. Once secure in the guiding catheter, the assembly
including the guiding catheter and errantly placed (for example)
IVC filter may be removed from the patient through the femoral
vein, for example.
[0018] In some embodiments, the eversion method may be used with
the present system to retrieve various objects from the vascular
system including IVC filters, guidewires, stents, coils, portions
of medical devices such as cardiac leads and other fractured
implants, and/or other objects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a cut-away isometric view of the first of a series
of figures (FIGS. 1-5) detailing a method of retrieving (e.g., via
eversion) a flexible IVC filter using a catheter-based extraction
device from a position inferior to the filter, or equivalently,
proximal to the operator. Here the extraction device is positioned
at the distal end of the guiding catheter.
[0020] FIG. 2 is a cut-away isometric view of the second of a
series of figures (FIGS. 1-5) detailing the method of retrieving
(e.g., via eversion) a flexible IVC filter using a catheter-based
extraction device from a position inferior to the filter, or
proximal to the operator. Here the extraction device is opened and
in position to grasp the tip of the filter.
[0021] FIG. 3 is a cut-away isometric view of the third of a series
of figures (FIGS. 1-5) detailing the method of retrieving (e.g.,
via eversion) a flexible IVC filter using a catheter-based
extraction device from a position inferior to the filter, and/or
proximal to the operator. Here the extraction device has secured
the tip of the filter and the operator has pulled the filter
proximal into the guiding catheter causing the flexible IVC to
commence eversion.
[0022] FIG. 4 is a cut-away isometric view of the fourth of a
series of figures (FIGS. 1-5) detailing the method of retrieving
(e.g., via eversion) a flexible IVC filter using a catheter-based
extraction device from a position inferior to the filter, or
proximal to the operator. Here the extraction device is within the
guiding catheter as the operator has everted the filter.
[0023] FIG. 5 is a cut-away isometric view of the fifth of a series
of figures (FIGS. 1-5) detailing the method of retrieving (via
eversion) a flexible IVC filter using a catheter-based extraction
device from a position inferior to the filter, or proximal to the
operator. Here the extraction device is positioned well within the
guiding catheter such that the everted IVC filter is secure within
the guiding catheter and ready to be removed from the body as an
integrated unit.
[0024] FIG. 6 is a view of the proximal end of the extraction
device featuring a handle used to actuate the distal end of the
extraction catheter to effect the grasping of the IVC filter.
[0025] FIG. 7 is a view of the delivery system with a flexible IVC
filter compressed and preloaded over a balloon at the distal end.
FIG. 7 also reveals a syringe with pressure gauge coupled to the
delivery system for optional ballooning of the IVC filter, together
with ancillary components including the guiding catheter and/or
introducer and dilator.
[0026] FIG. 8 is a view of the delivery system during the first
step of IVC filter deployment, namely unsheathing the filter.
[0027] FIG. 9 is a view of the delivery system during the second
step of IVC filter deployment, namely ballooning the filter to
achieve caval apposition.
[0028] FIG. 10 is a magnified view of the distal end of the
delivery system prior to IVC filter release showing a mechanism
that retrains the filter at the distal tip until it is deliberately
released.
[0029] FIG. 11 is a view of the internal mechanical workings of the
delivery system within the handle revealing an interlock feature
that prevents the filter from being deployed before caval
apposition has been achieved. The shown state is "locked" whereby a
pin in the filter release slide switch prevents the user from
releasing the filter.
[0030] FIG. 12 is a view of the internal mechanical workings of the
delivery system within the handle revealing the interlock feature
that prevents the filter from being deployed before caval
apposition has been achieved. The shown state is "unlocked" whereby
the pin is no longer preventing the proximal sliding of the switch
to release the filter.
[0031] FIG. 13 is a view of the delivery system during the third
step of the IVC filter deployment, namely releasing the filter.
[0032] FIG. 14 is a magnified view of the distal end of the
delivery system following release of the IVC filter revealing the
retention mechanism in the released state.
[0033] FIGS. 15-18 reveal the step by step process of releasing the
filter showing the retention mechanism in several sequential
positions.
[0034] FIG. 19 illustrates a method for delivering an object to,
and retrieving an object from, a location in a body cavity with a
delivery system.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Embodiments of the present invention will now be described
in detail with reference to the drawings, which are provided as
illustrative examples so as to enable those skilled in the art to
practice the invention. Notably, the figures and example below are
not meant to limit the scope of the present invention to a single
embodiment, but other embodiments are possible by way of
interchange of some or all of the described or illustrated
elements. Wherever convenient, the same reference numbers will be
used throughout the drawings to refer to same or like parts. Where
certain elements of these embodiments can be partially or fully
implemented using known components, only those portions of such
known components that are necessary for an understanding of the
present invention will be described, and detailed descriptions of
other portions of such known components will be omitted so as not
to obscure the invention. In the present specification, an
embodiment showing a singular component should not be considered
limiting. Rather, the invention is intended to encompass other
embodiments including a plurality of the same component, and
vice-versa, unless explicitly stated otherwise herein. Moreover,
applicants do not intend for any term in the specification or
claims to be ascribed an uncommon or special meaning unless
explicitly set forth as such. Further, the present invention
encompasses present and future known equivalents to the components
referred to herein by way of illustration. The terms "proximal" and
"distal" are used with reference to the operator of the extraction
device. In particular the distal end will be nearest to the object
of extraction, while the proximal end will be nearest to the
operator.
[0036] As used herein, the singular form of "a", "an", and "the"
include plural references unless the context clearly dictates
otherwise. As used herein, the statement that two or more parts or
components are "coupled" shall mean that the parts are joined or
operate together either directly or indirectly, i.e., through one
or more intermediate parts or components, so long as a link occurs.
As used herein, "directly coupled" means that two elements are
directly in contact with each other. As used herein, "fixedly
coupled" or "fixed" means that two components are coupled so as to
move as one while maintaining a constant orientation relative to
each other.
[0037] As used herein, the word "unitary" means a component is
created as a single piece or unit. That is, a component that
includes pieces that are created separately and then coupled
together as a unit is not a "unitary" component or body. As
employed herein, the statement that two or more parts or components
"engage" one another shall mean that the parts exert a force
against one another either directly or through one or more
intermediate parts or components. As employed herein, the term
"number" shall mean one or an integer greater than one (i.e., a
plurality).
[0038] Directional phrases used herein, such as, for example and
without limitation, top, bottom, left, right, upper, lower, front,
back, and derivatives thereof, relate to the orientation of the
elements shown in the drawings and are not limiting upon the claims
unless expressly recited therein.
[0039] The present invention relates generally to a method and
apparatus for deploying and retrieving an object (e.g., a vena cava
filter) in a cavity using a catheter configured to: (i) maintain
grip of the unsheathed object in the cavity until deliberately
released, (ii) prevent, using an interlock, premature release of
the object in the cavity, and/or (iii) facilitate retrieval by
first everting said object, then withdrawing the object through a
guiding catheter (e.g., retrieval via eversion).
[0040] Although the present invention can be used to deploy and
retrieve a plethora of implantable medical devices in a cavity,
deployment and retrieval of a flexible IVC filter intended to
prevent pulmonary embolism (PE) is shown and described herein as
one example embodiment to illustrate details of the present method
and apparatus. The flexibility of such an IVC filter often requires
ballooning during deployment, which poses both new challenges and
opportunities for their accompanying delivery systems. For example,
the increased flexibility of absorbable IVC filters enables
retrieval via the eversion method described herein (e.g., in the
event that the filter must be retrieved before resorption).
Consequently there is a current demand for the novel delivery
system described herein that can both accommodate and exploit the
unique features of a flexible IVC filter and/or other filters.
[0041] First, the retrieval via eversion method and apparatus will
be described using miniaturized grasping forceps to extract a
flexible IVC filter subsequent to deployment. Following such
description, the delivery system method and apparatus allowing both
deployment and retrieval of a flexible IVC filter will be described
in detail with the featured interlock mechanism to prevent
premature filter release. It should be noted, that even though
these descriptions are treated somewhat separately, both of these
descriptions refer to the components and operation of present
system 100.
[0042] Referring to FIGS. 1-5, a vessel and/or cavity 5 such as the
inferior vena cava (IVC) and/or other vessels and/or cavities is
shown to house (i) an IVC filter 4 comprising an inferior "stent"
portion 50 comprised of a high density weave of flexible filament
(for example) to maintain filter positioning within IVC 5 (e.g., by
pressing against a wall of the IVC) and a superior "capture basket"
51 comprising a low density weave of flexible filament (for
example) to capture thrombus, (ii) a guiding catheter 1 (e.g., a
portion of system 100) placed in vena cava 5 typically by insertion
into the femoral vein (but this is not intended to be limiting)
that serves as a conduit to the location 52 within IVC 5 for filter
4 placement, and (iii) extraction device catheter 2 (e.g., another
portion of system 100) housing the extraction or grasping
components and/or device 53 at the distal end 3 of catheter 2 and
the actuator controls (not shown in FIGS. 1-5) at the proximal end
54.
[0043] FIG. 1 depicts the distal end 3 of the extraction device 53
in the closed position (e.g., fully collapsed jaws) advanced to a
position at the distal end 55 of the guiding catheter 1. The
extraction device catheter 2 is further advanced 56 into the IVC
filter 4 (e.g., through an interior of portions 50 and 51) to reach
the (e.g., distal) end or tip 6 of the IVC filter 4 as shown in
FIG. 2. Once the distal end 57 of the extraction device 53 is
within proximity of the (e.g., distal) tip 6 of the IVC filter 4,
the controls (not shown in FIG. 2) are actuated by the operator at
the proximal end 54 of the extraction device catheter 2 to open the
jaws 7 of the extraction device 53 to grasp the tip 6 of the IVC
filter 4. Alternatively, the distal end 57 of the extraction device
53 could grasp a leg 58 or strut 59, or the other end of the filter
4.
[0044] Following secure grasping of the IVC filter 4 tip 6, the
extraction device catheter 2 is gently pulled proximally towards
the operator (e.g., toward end 54) causing the IVC filter 4 to
evert 60 as shown in FIG. 3. During eversion 60, regions of the
stent portion 50 of the IVC filter 4 will be pulled inside the
outer circumferential regions of the stent portion 50 of the IVC
filter 4 as depicted in region 8 (e.g., after portion 51 has also
passed through). Continued pulling of the extraction device
catheter 2 by the operator will facilitate complete eversion 60 of
the IVC filter 4 with the filter capture basket 51 now being
inferior with respect to the stent portion 50 of the filter 4 as
shown in FIG. 4, which is about 180.degree. opposite from the
original position 52 of the filter 4 (e.g., inverted via eversion).
That is, the IVC filter 4 is now positioned with the tip 6 and/or
capture basket 51 proximal, and the stent portion 50 distal. Also
as depicted in FIG. 4, the stent portion 50 of the flexible IVC
filter is compressed in region 9 as it enters the guiding catheter
1.
[0045] FIG. 5 depicts the IVC filter 4 completely everted and
secured within the guiding catheter 1. Region 10 shows the stent
portion 50 of the IVC filter 4 compressed within the guiding
catheter 1. The operator can now remove the entire assembly
including the guiding catheter 1 and extraction device catheter 2
with the captured and/or attached IVC filter 4 from the body (e.g.,
vena cava 5).
[0046] FIG. 6 illustrates the proximal end 25 of the extraction
device catheter 2 comprising a sliding handle 20, a thumb grip 21,
and/or other components. In one embodiment, the sliding handle 20
and thumb grip 21 are compressed 62 relative to each other to close
the jaws 7 (FIG. 2) at the distal end 57 of the extraction device
catheter 2, while extending 63 the sliding handle 20 and thumb grip
21 relative to each other will open the jaws 7. The actuation for
opening and closing the grasping mechanism (e.g., extraction device
53) can be built from cables or flexible rods, and/or other methods
as known in the art.
[0047] FIGS. 7-18 illustrate deploying and retrieving a flexible
IVC filter. For example, FIG. 7-18 illustrate: (i) maintaining a
grip on an unsheathed filter in the IVC until deliberately
released, (ii) interlocking preventing premature release of the
filter in the IVC, and (iii) retrieval by first everting said
filter and then withdrawing it through a guiding catheter (e.g.,
retrieval via eversion).
[0048] FIG. 7 illustrates delivery system 100 and ancillary
components including a guiding catheter and/or introducer 200
(e.g., similar to and/or the same as guiding catheter 1 described
above), a dilator 299 that is inserted in the introducer 200 over a
guide wire 201 for IVC filter deployment, a valve 119, a pressure
gage 120 that indicates pressure of liquid in delivery system 100
(e.g., contrast solution and/or other liquids forced into delivery
system 100 by plunger 122), tubing 222 that conducts fluid from the
pressure gage 120 and plunger 122 to other components of the
present system (e.g., as described herein), various luer fittings
107 and/or other coupling components 109 configured to removably
couple one or more components of the present system to each other
and/or outside systems, and/or other components. The delivery
system 100 includes a handle 104, safety release indicator 105
(e.g., shown in locked position), filter release switch 106,
unsheathing barrel slide 103, outer catheter 102, preloaded
flexible IVC filter 101 (e.g., which is similar to and/or the same
as filter 4 described above), and/or other components.
[0049] Filter deployment with the delivery system 100 includes
pulling (e.g., by an operator) the barrel slide 103 proximally 204,
which effectively pulls the outer catheter 102 and introducer 200
proximally 204 to unsheathe the filter 101 as shown in FIGS. 7 and
8. It should be noted that the introducer 200 is coupled with the
barrel slide 103 such that when the barrel slide 103 is pulled
proximally 204, both the introducer 200 and outer sheath 102 are no
longer positioned over the compressed IVC filter 101.
[0050] Filter deployment with the delivery system 100 includes
"ballooning" the compressed flexible IVC filter 101 (e.g.,
expanding the diameter of the IVC filter 101 compressed over the
balloon to fit snug against the IVC wall) as shown in FIG. 9. As
shown in FIG. 9, a plunger 122 of a syringe 121 filled with diluted
contrast solution and/or other materials is pushed (e.g., by an
operator) distally 220, forcing contrast solution into the balloon
130 (e.g., through tubing 220 and/or tubing included in catheter
200), thereby expanding the diameter of the filter 101 in the IVC
to ensure caval apposition, for example. As caval apposition is
achieved (and/or at other times), the semi-compliant (for example)
balloon 130 may form a "dog bone" shape 132 that may be revealed on
a fluoroscope and/or other equipment (for example).
[0051] As shown in the magnified view in FIG. 10, the filter 101 is
retained during the ballooning step by the retention tube 150 with
retention fingers 151 that prevent the distal tip 170 of the IVC
filter 101 from migrating downstream. Once the balloon 130 (FIG. 9)
forms the "dog bone" shape (for example) indicating caval
apposition, it can be subsequently evacuated by pulling the plunger
122 (FIG. 9) proximally.
[0052] An interlock mechanism 300 within the handle 104 (FIG. 9) of
the delivery system 100 (FIG. 9) is shown in FIGS. 11 and 12. The
interlock mechanism 300 is configured to facilitate prevention of
premature release of the IVC filter 101 (FIG. 9), that is,
releasing the filter 101 before caval apposition is achieved. FIG.
11 illustrates the interlock mechanism in the "locked" state 301
whereby the release switch 106 is prevented from sliding proximally
250 (FIG. 12) by the pin 180 that is recessed into the release
switch 106. The release switch 106 is coupled with the interlock
rod 155 (described below) and the retention tube 150 (described
below) that together retain the filter 101 with the delivery system
100, thereby preventing premature release of the filter (e.g., as
described below).
[0053] FIG. 12 illustrates the interlock mechanism 300 in the
"unlocked" state 302 that occurs once the balloon 130 (FIG. 9) has
reached a designated pressure (for example) corresponding to caval
apposition, typically about 15 psi and/or other pressures for IVC
filter applications, for example. During the ballooning process,
the increased balloon pressure 187 within the tube 186 (which is
similar to and/or the same as tubing 222 described above) leading
to the interlock mechanism 300 will force 306 the piston 184 to
slide within a cylinder 308 which in turn causes the spring loaded
trigger 182 to fall 310 since a portion 314 of trigger 182 is
positioned on a ledge 312 in contact with the piston 184 indirectly
through the translator 183. As the spring loaded trigger 182 (note
spring 181) falls 310 (and/or is pushed by spring 181), the pin 180
disengages from the release switch 106 allowing the IVC filter to
be released. The translator 183 is configured to deliver force from
the piston 184 to the bottom (for example) of the trigger 182 that
is positioned on the ledge 312.
[0054] In some embodiments, the spring loaded trigger 182 includes
a body 361, a foot portion 363, a leg portion 365 extending between
the body 361 and the foot portion 363, and/or other components. In
some embodiments, body 361 includes a sleeve, groove, and/or other
components 367 configured to receive an end of the pin 180. The
foot portion 363 is operatively coupled to the piston 184 via
translator 183. The foot portion 363 is supported by the ledge 312
and configured to be pushed off the ledge 312 by the piston 184
(via translator 183) and cause the spring loaded trigger 182 to
disengage the release switch 106 (e.g., when body 361, leg portion
365, and foot portion 363 fall 310 (and/or are pushed by spring
181). In some embodiments, the ledge 312 is formed by a portion of
cylinder 308. In some embodiments ledge 312 is formed by a portion
of cylinder 308 that is opposite orifice 185 (described below). In
some embodiments, leg portion 365 extends from body 361 toward
ledge 312 such that foot portion 363 rests on ledge 312 as shown
and described.
[0055] Orifice 185 is configured to facilitate avoidance of
erroneous triggering of the interlock mechanism 300 in the event
the operator pushes the syringe plunger 122 (FIG. 9) abruptly,
causing a temporary spike in balloon pressure, well before caval
apposition is achieved at the steady state pressure of
approximately 15 psi (for example). The diameter 370 of orifice 185
is sized to prevent such pressure spikes that could inadvertently
trigger the interlock mechanism 300. In some embodiments, the
orifice 185 has a cylindrical cross section with a diameter 370
that is smaller than a diameter 372 of the cylinder 308 and a
length 374 that is shorter than a length 376 of the cylinder 308.
In some embodiments, diameter 370 is up to about 5 mm. In some
embodiments, diameter 370 is between about 0.25 mm and about 1 mm.
In some embodiments, diameter 370 is about 0.5 mm. In some
embodiments, diameter 372 is up to about 20 mm. In some
embodiments, diameter 372 is between about 5 mm and about 20 mm. In
some embodiments, diameter 372 is about 10 mm.
[0056] In some embodiments, orifice 185 and cylinder 308 are
oriented along a first axis 378 of handle 104 such that length 374
and length 376 extend along axis 378. In some embodiments, spring
loaded trigger 182, spring 181, and pin 180 occupy a second
cylinder 390 that is oriented along a second axis 392 of handle
104. In some embodiments, second axis 392 and first axis 378 are
substantially perpendicular to each other. In some embodiments,
spring loaded trigger 182 falls 310 (and/or is pushed by spring
181) in cylinder 390 responsive to foot portion 314 of trigger 182
sliding off of ledge 312 when pushed by the translator 183 and the
piston 184.
[0057] Delivery system 100 (FIG. 9) facilitates releasing the
filter 101 (FIG. 9) by sliding the release switch 106 proximally
250 (FIG. 12) once the interlock mechanism 300 is disengaged (FIG.
12). In some embodiments, delivery system 100 is configured such
that disengagement (and/or conversely engagement) of interlock
mechanism 300 is indicated by an indicator on handle 104 and/or
other components of delivery system 100. For example, FIG. 13
illustrates an unlocked padlock symbol 105 (which would show as
locked if mechanism 300 was engaged). The indicator can be changed
from a locked symbol to an unlocked symbol (both symbols printed on
a lever) by a spring-loaded sliding lever that is substantially
simultaneously activated by triggering of the interlock mechanism
300. A magnified view of the retention tube 150 and the retention
fingers 151 with handle 104 in the "unlocked" state is shown in
FIG. 14. Here the retention tube 150 has been pulled proximally 350
relative to the distal tip 170 of the IVC filter 101, thereby no
longer being in contact with the filter 101.
[0058] A series of magnified figures (FIGS. 15-18) illustrate the
sequential release of the IVC filter 101 from the delivery system
100 (FIG. 7-9) by sliding and/or otherwise moving the filter
release switch 106 (FIG. 9) proximally 250 (FIG. 12). As the filter
release switch 106 is moved proximally 250, a first inner lock rod
155 slides and/or otherwise moves proximally 360, enabling and/or
otherwise facilitating the collapse 362 (e.g., pinching toward each
other) of the retention fingers 151. The retention fingers 151 on
the retention tube 150 collapse as they traverse proximally through
the center hole 364 of the IVC filter 101 distal tip 170 as
detailed in FIGS. 16 and 17, for example. In some embodiments,
another tube such as the balloon tube 160 provides a backstop 366
preventing proximal motion of the IVC filter 101 while the
retention tube 150 and lock rod 155 are pulled proximally 360. Once
the retention fingers 151 are positioned proximal to the distal tip
170 of the IVC filter 101, the filter 101 is easily released as
shown in FIG. 18. In some embodiments, retention tube 150 and/or
lock rod 155 may be and/or include stainless steel (and/or other
materials) hypotubes (and/or other devices), for example.
[0059] In some embodiments, e.g., when it is desired to retrieve
the IVC filter immediately following insertion in the IVC due to
malposition, inappropriate sizing, and/or for other reasons, it is
possible to use the retention mechanism represented, for example,
by the retention fingers 151 of the retention tube 150 together
with the lock rod 155 in the lock position (e.g., FIG. 10, 15) to
facilitate retrieval via eversion and/or other methods, for
example. In such embodiments, the introducer 200 may be uncoupled
from the delivery system barrel 103 (FIG. 13) and the delivery
system handle 104 may be pulled proximally, while the introducer
200 is held substantially stationary. Since the retention fingers
will remain distal to the filter end plate 170 in the locked
position, this effort will cause the flexible IVC filter 101 (e.g.,
attached to the delivery system 100 by the retention mechanism) to
evert and be pulled into the introducer 200 for easy removal
without requiring any additional components or equipment.
[0060] It should be noted that the shapes (e.g., cylindrical, etc.)
and dimensions described herein are not intended to be limiting.
The components of the present system may have any shape and/or size
that allows them to function as described herein.
[0061] FIG. 19 illustrates a method 400 for delivering an object
to, and retrieving an object from, a location in a body cavity with
a delivery system. The system comprises a guiding catheter, object
deployment components, an interlock mechanism, a retention
mechanism, and/or other components. The operations of method 400
presented below are intended to be illustrative. In some
embodiments, method 400 may be accomplished with one or more
additional operations not described, and/or without one or more of
the operations discussed. Additionally, the order in which the
operations of method 400 are illustrated in FIG. 19 and described
below is not intended to be limiting.
[0062] At an operation 402, a conduit is formed to and from the
location for the object in the body cavity. In some embodiments,
operation 402 is performed by a guiding catheter similar to and/or
the same as guiding catheter 1 (shown in FIG. 1 and described
herein) and/or guiding catheter 200 (shown in FIG. 7 and described
herein).
[0063] At an operation 404, deployment of the object is
facilitated. In some embodiments, deployment is facilitated with
object deployment components. In some embodiments, the object
deployment components comprise a balloon configured to expand the
object at the location, a pressure gage, fluid, a plunger, and/or
other components. In some embodiments, operation 404 is performed
by object deployment components the same as or similar to delivery
system 100, dilator 299, guide wire 201, handle 104, balloon 130,
pressure gage 120, syringe 121 filled with diluted contrast
solution, plunger 122 (shown in FIG. 7-13 and described herein),
and/or other components.
[0064] At an operation 406, release of the object at the location
before a target position is achieved is prevented. In some
embodiments, operation 406 is performed by an interlock mechanism
similar to and/or the same as interlock mechanism 300 (shown in
FIG. 11-12 and described herein). In some embodiments, operation
406 includes preventing, with the interlock mechanism, premature
release of the object before the object is balloon expanded to a
predetermined pressure. In some embodiments, the interlock
mechanism comprises a piston in a cylinder that is advanced through
the cylinder by balloon pressure; and a spring loaded trigger
operatively coupled to the piston configured to move responsive to
movement by the piston to disengage a release switch to facilitate
release of the object at the location in the cavity. In some
embodiments, the interlock mechanism comprises an orifice and/or
other components. The orifice is configured to conduct the balloon
pressure to the cylinder. In some embodiments, the orifice has a
diameter that is smaller than a diameter of the cylinder and a
length that is shorter than a length of the cylinder. In some
embodiments, the spring loaded trigger includes a body, a foot
portion, and a leg portion extending between the body and the foot
portion. The foot portion is operatively coupled to the piston. In
some embodiments, the foot portion is supported by a ledge and
configured to be pushed off the ledge by the piston and cause the
spring loaded trigger to disengage the release switch.
[0065] At an operation 408, the object is secured while the object
is in the cavity. In some embodiments, operation 408 is caused by a
retention mechanism similar to and/or the same as the retention
mechanism formed by retention tube 150 and retention fingers 151
(shown in FIGS. 10, 14, and 15-18, and described herein). In some
embodiments, the retention mechanism is activated by the interlock
mechanism to release the object at the location in the cavity. In
some embodiments, the retention mechanism comprises an outer tube
with distal fingers that protrude distally through an opening in a
distal end of the object; and an inner rod or tube within the outer
tube that prevents the distal fingers on the outer tube from
collapsing. In some embodiments, responsive to the inner rod being
withdrawn proximally with respect to the outer tube, the distal
fingers of the outer tube collapse to facilitate withdrawal of the
distal fingers through the opening in the (e.g., distal) end of the
object, and withdrawal of the inner rod and the outer tube from the
object, thereby releasing the object at the location within the
cavity.
[0066] At an operation 410, the object is grasped and extracted
from the location in the cavity. In some embodiments, operation 410
occurs after the object has been deployed at the location in the
body. In some embodiments, operation 410 is caused by a grasping
and extraction device similar to and/or the same as extraction
device catheter 2, extraction device 53, and/or a sliding handle 20
and thumb grip 21 (shown in FIG. 1-6 and described herein). In some
embodiments, the extraction device catheter is configured such that
grasping and extraction components are located at a distal end of
the extraction device catheter and actuator controls (e.g., sliding
handle 20 and/or thumb grip 21) for the grasping and extraction
components are located at a proximal end of the extraction device
catheter. In some embodiments, the extraction device catheter is
configured such that the actuator controls comprise the sliding
handle and thumb grip located at the proximal end of the extraction
device catheter. In some embodiments, the operation 410 comprises
compressing the sliding handle and thumb grip relative to each
other to cause the grasping and extraction components to grasp the
object, and extending the sliding handle and thumb grip relative to
each other to cause the grasping and extraction components to
release the object.
[0067] In some embodiments (e.g., before the object is fully
deployed at the location in the cavity), operation 410 is caused by
retaining grip of the device using a combination of retention tube
150 with retention fingers 151 and an inner lock tube 155, such
grip being strong enough to facilitate retrieval via eversion as
described previously.
[0068] In some embodiments, the grasping and extraction components
comprise jaws configured to close around the (e.g., distal) end of
a vena cava filter responsive to the sliding handle and thumb grip
being compressed relative to each other. In some embodiments, the
object is a vena cava filter, and operation 410 includes advancing
the extraction device catheter through the guiding catheter to the
location of the object and grasping and securing the object
responsive to the sliding handle and thumb grip being compressed
relative to each other; and enabling a user to pull proximally on
the end of the vena cava filter causing the vena cava filter to
evert, and with continued pulling advance the vena cava filter into
the guiding catheter for removal from the cavity.
[0069] In the claims, any reference signs placed between
parentheses shall not be construed as limiting the claim. The word
"comprising" or "including" does not exclude the presence of
elements or steps other than those listed in a claim. In a device
claim enumerating several means, several of these means may be
embodied by one and the same item of hardware. The word "a" or "an"
preceding an element does not exclude the presence of a plurality
of such elements. In any device claim enumerating several means,
several of these means may be embodied by one and the same item of
hardware. The mere fact that certain elements are recited in
mutually different dependent claims does not indicate that these
elements cannot be used in combination.
[0070] Although the description provided above provides detail for
the purpose of illustration based on what is currently considered
to be the most practical and preferred embodiments, it is to be
understood that such detail is solely for that purpose and that the
disclosure is not limited to the expressly disclosed embodiments,
but, on the contrary, is intended to cover modifications and
equivalent arrangements that are within the spirit and scope of the
appended claims. For example, it is to be understood that the
present disclosure contemplates that, to the extent possible, one
or more features of any embodiment can be combined with one or more
features of any other embodiment.
* * * * *