U.S. patent application number 11/289979 was filed with the patent office on 2006-04-13 for bronchial flow control devices and methods of use.
This patent application is currently assigned to Emphasys Medical, Inc., a Delaware corporation. Invention is credited to Michael Barrett, Alan Rapacki.
Application Number | 20060076023 11/289979 |
Document ID | / |
Family ID | 36144050 |
Filed Date | 2006-04-13 |
United States Patent
Application |
20060076023 |
Kind Code |
A1 |
Rapacki; Alan ; et
al. |
April 13, 2006 |
Bronchial flow control devices and methods of use
Abstract
A flow control device includes a sealing component that can be
positioned within a bronchial lumen. The sealing component can
comprise two or more overlapping segments that are movable relative
to one another such that the segments collectively form a seal that
can expand and contract in size to fit within and seal bronchial
lumens of various sizes.
Inventors: |
Rapacki; Alan; (Redwood
City, CA) ; Barrett; Michael; (Campbell, CA) |
Correspondence
Address: |
FISH & RICHARDSON, PC
P.O. BOX 1022
MINNEAPOLIS
MN
55440-1022
US
|
Assignee: |
Emphasys Medical, Inc., a Delaware
corporation
|
Family ID: |
36144050 |
Appl. No.: |
11/289979 |
Filed: |
November 29, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10627517 |
Jul 25, 2003 |
|
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|
11289979 |
Nov 29, 2005 |
|
|
|
60399273 |
Jul 26, 2002 |
|
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60429902 |
Nov 27, 2002 |
|
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Current U.S.
Class: |
128/207.15 ;
128/207.14; 128/207.16 |
Current CPC
Class: |
A61F 2/91 20130101; A61F
2/2427 20130101; A61B 17/12022 20130101; A61F 2/04 20130101; A61F
2002/043 20130101; A61F 2230/0078 20130101; A61F 2/2418 20130101;
A61F 2230/0076 20130101; A61F 2230/0067 20130101; A61F 2/06
20130101; A61B 2017/12054 20130101; A61F 2220/0041 20130101; A61B
2090/061 20160201; A61F 2/2412 20130101; A61B 17/12104 20130101;
A61B 17/12172 20130101; A61B 17/221 20130101; Y10S 128/912
20130101; A61F 2/2476 20200501; A61B 17/1204 20130101; F16K 15/147
20130101; A61F 2230/0093 20130101; A61F 2230/005 20130101; A61B
17/12036 20130101; A61B 2017/1205 20130101; A61F 2230/0054
20130101 |
Class at
Publication: |
128/207.15 ;
128/207.16; 128/207.14 |
International
Class: |
A62B 9/06 20060101
A62B009/06; A61M 16/00 20060101 A61M016/00 |
Claims
1. A flow control device for placement in a bronchial passageway
comprising: a frame configured to move between a contracted
configuration and an expanded configuration, the frame comprising a
plurality of struts, the struts being fixed at a distal hub and a
proximal hub of the frame, wherein the struts are biased outward
and self-expand when unimpeded, and wherein the struts of the frame
form a tube shape when the frame is in the contracted
configuration, and when in the expanded configuration the struts of
the frame expand between the distal and proximal hubs to an outward
diameter such that the diameter of the frame at the hubs is tapered
compared to the diameter of the frame between the hubs thereby
forming a seal with the bronchial passageway.
2. The flow control device of claim 1, wherein a membrane is draped
over the struts such that the membrane seals against the bronchial
passageway when the frame is in the expanded configuration.
3. The flow control device of claim 1, wherein expansion of the
struts reaches an outwardmost diameter midway between the distal
and proximal hubs.
4. The flow control device of claim 1, further comprising a
retainer element protruding laterally from the frame to prevent
migration of the flow control device in the bronchial
passageway.
5. The flow control device of claim 1, wherein the struts are
curved.
6. A flow control device for placement in a bronchial passageway
comprising: a frame comprising a plurality of struts having distal
ends coupled to a distal hub and proximal ends connected to a
proximal hub, the struts being outwardly expanded therebetween,
wherein the frame urges a membrane into engagement with a wall of
the bronchial passageway to form a seal therewith.
7. The flow control device of claim 6, wherein a membrane is draped
over the struts such that the membrane seals against the wall of
the bronchial passageway when the struts are outwardly
expanded.
8. The flow control device of claim 6, wherein expansion of the
struts reaches an outwardmost diameter midway between the distal
and proximal hubs.
9. The flow control device of claim 6, further comprising a
retainer element protruding laterally from the frame to prevent
migration of the flow control device in the bronchial
passageway.
10. The flow control device of claim 6, wherein the struts are
curved.
Description
REFERENCE TO PRIORITY DOCUMENTS
[0001] This application is a continuation of co-pending U.S. patent
application Ser. No. 10/627,517, entitled "Bronchial Flow Control
Devices and Methods of Use", filed Jul. 25, 2003, which claims
priority of the following U.S. Provisional Patent Applications: (1)
U.S. Provisional Patent Application Ser. No. 60/399,273, entitled
"Implantable Bronchial Isolation Devices", filed Jul. 26, 2002; and
(2) U.S. Provisional Patent Application Ser. No. 60/429,902,
entitled "Implantable Bronchial Isolation Devices", filed Nov. 27,
2002. Priority of the aforementioned filing dates is hereby
claimed, and the disclosures of the Provisional Patent Applications
are hereby incorporated by reference in their entirety.
[0002] This application is also related to the following patent
applications: (1) U.S. patent application Ser. No. 09/797,910,
entitled "Methods and Devices for Use in Performing Pulmonary
Procedures", filed Mar. 2, 2001; and (2) U.S. patent application
Ser. No. 10/270,792, entitled "Bronchial Flow Control Devices and
Methods of Use", filed Oct. 10, 2002. The aforementioned
applications are hereby incorporated by reference in their
entireties.
BACKGROUND
[0003] This disclosure relates generally to methods and devices for
use in performing pulmonary procedures and, more particularly, to
procedures for treating various lung diseases.
[0004] Pulmonary diseases, such as chronic obstructive pulmonary
disease, (COPD), reduce the ability of one or both lungs to fully
expel air during the exhalation phase of the breathing cycle. The
term "Chronic Obstructive Pulmonary Disease" (COPD) refers to a
group of diseases that share a major symptom, dyspnea. Such
diseases are accompanied by chronic or recurrent obstruction to air
flow within the lung. Because of the increase in environmental
pollutants, cigarette smoking, and other noxious exposures, the
incidence of COPD has increased dramatically in the last few
decades and now ranks as a major cause of activity-restricting or
bed-confining disability in the United States. COPD can include
such disorders as chronic bronchitis, bronchiectasis, asthma, and
emphysema. While each has distinct anatomic and clinical
considerations, many patients may have overlapping characteristics
of damage at both the acinar (as seen in emphysema) and the
bronchial (as seen in bronchitis) levels.
[0005] Emphysema is a condition of the lung characterized by the
abnormal permanent enlargement of the airspaces distal to the
terminal bronchiole, accompanied by the destruction of their walls,
and without obvious fibrosis. (Snider, G. L. et al: The Definition
of Emphysema: Report of the National Heart Lung And Blood
Institute, Division of lung Diseases Workshop. (Am Rev. Respir.
Dis. 132:182, 1985). It is known that emphysema and other pulmonary
diseases reduce the ability of one or both lungs to fully expel air
during the exhalation phase of the breathing cycle. One of the
effects of such diseases is that the diseased lung tissue is less
elastic than healthy lung tissue, which is one factor that prevents
full exhalation of air. During breathing, the diseased portion of
the lung does not fully recoil due to the diseased (e.g.,
emphysematic) lung tissue being less elastic than healthy tissue.
Consequently, the diseased lung tissue exerts a relatively low
driving force, which results in the diseased lung expelling less
air volume than a healthy lung. The reduced air volume exerts less
force on the airway, which allows the airway to close before all
air has been expelled, another factor that prevents full
exhalation.
[0006] The problem is further compounded by the diseased, less
elastic tissue that surrounds the very narrow airways that lead to
the alveoli, which are the air sacs where oxygen-carbon dioxide
exchange occurs. The diseased tissue has less tone than healthy
tissue and is typically unable to maintain the narrow airways open
until the end of the exhalation cycle. This traps air in the lungs
and exacerbates the already-inefficient breathing cycle. The
trapped air causes the tissue to become hyper-expanded and no
longer able to effect efficient oxygen-carbon dioxide exchange.
[0007] In addition, hyper-expanded, diseased lung tissue occupies
more of the pleural space than healthy lung tissue. In most cases,
a portion of the lung is diseased while the remaining part is
relatively healthy and, therefore, still able to efficiently carry
out oxygen exchange. By taking up more of the pleural space, the
hyper-expanded lung tissue reduces the amount of space available to
accommodate the healthy, functioning lung tissue. As a result, the
hyper-expanded lung tissue causes inefficient breathing due to its
own reduced functionality and because it adversely affects the
functionality of adjacent healthy tissue.
[0008] Lung reduction surgery is a conventional method of treating
emphysema. According to the lung reduction procedure, a diseased
portion of the lung is surgically removed, which makes more of the
pleural space available to accommodate the functioning, healthy
portions of the lung. The lung is typically accessed through a
median sternotomy or small lateral thoracotomy. A portion of the
lung, typically the periphery of the upper lobe, is freed from the
chest wall and then resected, e.g., by a stapler lined with bovine
pericardium to reinforce the lung tissue adjacent the cut line and
also to prevent air or blood leakage. The chest is then closed and
tubes are inserted to remove air and fluid from the pleural cavity.
The conventional surgical approach is relatively traumatic and
invasive, and, like most surgical procedures, is not a viable
option for all patients.
[0009] Some recently proposed treatments include the use of devices
that isolate a diseased region of the lung in order to reduce the
volume of the diseased region, such as by collapsing the diseased
lung region. According to such treatments, isolation devices are
implanted in airways feeding the targeted region of the lung to
regulate fluid flow to the diseased lung region in order to fluidly
isolate the region of the lung. These implanted isolation devices
can be, for example, one-way valves that allow flow in the
exhalation direction only, occluders or plugs that prevent flow in
either direction, or two-way valves that control flow in both
directions. However, such devices are still in the development
stages. For example, some valves have been found to wrinkle and
create fluid leak paths when implanted in a bronchial lumen of a
diameter other than that near the diameter of the valve. Thus,
there is much need for improvement in the design, flexibility, and
functionality of such isolation devices.
[0010] In view of the foregoing, there is a need for improved
methods and devices for regulating fluid flow to a diseased lung
region.
SUMMARY
[0011] Disclosed are methods and devices for regulating fluid flow
to and from a region of a patient's lung, such as to achieve a
desired fluid flow dynamic to a lung region during respiration
and/or to induce collapse in one or more lung regions. In one
aspect, there is disclosed a flow control device that can be
implanted in a bronchial passageway. The flow control device can
include a sealing component that can be positioned within a
bronchial lumen. The sealing component can comprise two or more
overlapping segments that are movable relative to one another such
that the segments collectively form a seal that can expand and
contract in size to fit within and seal bronchial lumens of various
sizes.
[0012] Also disclosed is a flow control device that can be
implanted in a bronchial passageway. The flow control device
comprises a retainer frame comprising a core, a first set of
deployable arms projecting from the core, and a second set of
deployable arms projecting from the core. The flow control device
further comprises a sealing component comprising two or more
overlapping segments that are movable relative to one another such
that the segments collectively form a seal that can expand and
contract in size to fit within and seal bronchial lumens of various
sizes.
[0013] Also disclosed is a method of regulating fluid flow to and
from a region of an individual's lung. The method comprises placing
a flow control device in a bronchial passage in communication with
the region, the flow control device having a first set of one or
more deployable arms in a collapsed configuration; and radially
expanding the first set of one or more deployable arms into
engagement with a wall of the bronchial passage to anchor the flow
control device therein. The flow control device has a plurality of
overlapping segments that are movable relative to one another and
collectively form a seal with a wall of the bronchial lumen that
can expand and contract in size.
[0014] Also disclosed is a flow control device for placement in a
body lumen. The flow control device can comprise a frame comprising
a plurality of struts connected to a distal hub, at least a portion
of each strut biased outwardly from the distal hub. The flow
control device further comprises a membrane coupled to the struts
thereby forming an umbrella shape. The frame urges the membrane
into engagement with a wall of the body lumen to form a seal
therewith.
[0015] Other features and advantages should be apparent from the
following description of various embodiments, which illustrate, by
way of example, the principles of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows an anterior view of a pair of human lungs and a
bronchial tree with a flow control device implanted in a bronchial
passageway to bronchially isolate a region of the lung.
[0017] FIG. 2 shows an anterior view of a pair of human lungs and a
bronchial tree.
[0018] FIG. 3A shows a lateral view of the right lung.
[0019] FIG. 3B shows a lateral view of the left lung.
[0020] FIG. 4 shows an anterior view of the trachea and a portion
of the bronchial tree.
[0021] FIG. 5A shows a perspective view of a first embodiment of a
flow control device that can be implanted in a body passageway.
[0022] FIG. 5B shows a perspective, cross-sectional view of the
flow control device of FIG. 5A.
[0023] FIG. 6A shows a side view of the flow control device of FIG.
5A.
[0024] FIG. 6B shows a cross-sectional, side view of the flow
control device of FIG. 5A.
[0025] FIG. 7A shows a side, cross-sectional view of a duckbill
valve in a closed state.
[0026] FIG. 7B shows a side, cross-sectional view of a duckbill
valve in an open state.
[0027] FIG. 8 shows the flow control device of FIGS. 5-6 implanted
in a bronchial passageway.
[0028] FIG. 9 shows a perspective, cross-sectional view of another
embodiment of the flow control device.
[0029] FIG. 10 shows a side, cross-sectional view of the flow
control device of FIG. 9.
[0030] FIG. 11 shows a front, plan view of the flow control device
of FIG. 9.
[0031] FIG. 12 shows the flow control device of FIG. 9 implanted in
a bronchial passageway.
[0032] FIG. 13 shows the flow control device of FIG. 9 implanted in
a bronchial passageway and dilated by a dilation device comprised
of a tube.
[0033] FIG. 14 shows the flow control device of FIG. 9 implanted in
a bronchial passageway and dilated by a dilation device comprised
of a tube with a one-way valve.
[0034] FIG. 15 shows the flow control device of FIG. 9 implanted in
a bronchial passageway and dilated by a dilation device comprised
of a tube with a one way valve, wherein the tube is attached to a
removal tether.
[0035] FIG. 16 shows the flow control device of FIG. 9 implanted in
a bronchial passageway and dilated by a dilation device comprised
of a tube, which is fluidly coupled to a catheter.
[0036] FIG. 17 shows the flow control device of FIG. 9 implanted in
a bronchial passageway and dilated by a dilation device comprised
of a catheter.
[0037] FIG. 18 shows another embodiment of a flow control device
implanted in a bronchial passageway.
[0038] FIG. 19 shows a perspective view of another embodiment of a
flow control device.
[0039] FIG. 20 shows a side view of the flow control device of FIG.
19.
[0040] FIG. 21 shows a cross-sectional view of the flow control
device of FIG. 20 cut along the line 21-21 of FIG. 20.
[0041] FIG. 22 shows another embodiment of a flow control
device.
[0042] FIG. 23 shows a cross-sectional view of the flow control
device of FIG. 22.
[0043] FIG. 24 shows a perspective view of another embodiment of a
flow control device.
[0044] FIG. 25 shows another embodiment of a flow control device
implanted in a bronchial passageway.
[0045] FIG. 26 shows another embodiment of a flow control device
implanted in a bronchial passageway.
[0046] FIG. 27 shows the flow control device of FIG. 26 implanted
in a bronchial passageway and dilated by a dilation device.
[0047] FIG. 28 shows another embodiment of a flow control device
implanted in a bronchial passageway.
[0048] FIG. 29 shows another embodiment of a flow control device
implanted in a bronchial passageway that has an internal, sealed
chamber.
[0049] FIG. 30 shows another embodiment of a flow control device
implanted in a bronchial passageway, the flow control device having
a pair of internal lumens for allowing controlled, two-way fluid
flow.
[0050] FIG. 31 shows another embodiment of a flow control device
implanted in a bronchial passageway, the flow control device having
a pair of flap valves for allowing controlled, two-way fluid
flow.
[0051] FIG. 32 shows a delivery system for delivering a flow
control device to a target location in a body passageway.
[0052] FIG. 33 shows a perspective view of a distal region of a
delivery catheter of the delivery system.
[0053] FIG. 34 shows a plan, side view of the distal region of the
delivery catheter.
[0054] FIG. 35A shows a cross-sectional view of a housing of the
delivery catheter, the housing containing a flow control
device.
[0055] FIG. 35B shows a cross-sectional view of the housing
containing a flow control device that has a distal end that
protrudes from the housing.
[0056] FIG. 36A shows the delivery catheter housing containing a
flow control device and implanted at a location L of a bronchial
passageway.
[0057] FIG. 36B shows the delivery catheter deploying the flow
control device at the location L of the bronchial passageway.
[0058] FIG. 37 shows the delivery catheter deploying the flow
control device distally of the location L of the bronchial
passageway.
[0059] FIG. 38 is a perspective view of a loader system for loading
the flow control device onto a delivery catheter.
[0060] FIG. 39 shows a cross-sectional side view of a loader device
of the loader system.
[0061] FIG. 40 shows a perspective view of a pusher device of the
loader system.
[0062] FIG. 41 shows the loader system readied for loading the flow
control device into the housing of the delivery catheter.
[0063] FIG. 42 shows the loader system being used to compress the
flow control device during loading of the flow control device into
the housing of the delivery catheter.
[0064] FIG. 43 shows the loader system being used to compress the
flow control device during insertion of the flow control device
into the housing of the delivery catheter.
[0065] FIG. 44 shows the loader system with the flow control device
fully loaded into the housing of the delivery catheter.
[0066] FIG. 45 shows an exploded, perspective rear view of the
loader device of the loader system.
[0067] FIG. 46 shows a plan, rear view of the loader device of the
loader system with a delivery door in a closed position.
[0068] FIG. 47 shows a plan, rear view of the loader device of the
loader system with a delivery door in an open position.
[0069] FIG. 48A shows a perspective, rear view of the loader device
of the loader system with the delivery door in an open position and
the catheter housing inserted into the loader device.
[0070] FIG. 48B shows a perspective, rear view of the loader device
of the loader system with the delivery door in a closed position
and the catheter housing mated with the loader device.
[0071] FIG. 49 shows a perspective view of a loading tube of the
loader system.
[0072] FIG. 50A shows the loading tube being used to initially
insert the flow control device into the loader device.
[0073] FIG. 50B shows the loading tube being used to initially
insert the flow control device into the loader device.
[0074] FIG. 51 shows another embodiment of a pusher device.
[0075] FIG. 52A shows the pusher device of FIG. 51 initially
inserted into the loader device.
[0076] FIG. 52B shows the pusher device of FIG. 51 fully inserted
into the loader device.
[0077] FIG. 53 shows an exploded, perspective another embodiment of
the loader system.
[0078] FIG. 54 shows an exploded, perspective another embodiment of
the loader system with the pusher device inserted into the loader
device.
[0079] FIG. 55 shows a front, plan view of another embodiment of a
loader device.
[0080] FIG. 56 shows a side, plan view of the loader device of FIG.
55.
[0081] FIG. 57 shows a front, plan view of the loader device of
FIG. 55 in a closed state.
[0082] FIG. 58 shows a side, plan view of the loader device of FIG.
55.
[0083] FIG. 59 shows a perspective view of a flow control device
having a segmented valve/seal component.
[0084] FIG. 60 is a front plan view of the valve/seal component of
the flow control device depicted in FIG. 59.
[0085] FIG. 60B shows a perspective view of a flow control device
having a segmented valve/seal component and shows enlarged views of
two embodiments of foldable sections.
[0086] FIG. 61 is a side view of the flow control device depicted
in FIG. 59.
[0087] FIG. 62 is a side view of the flow control device depicted
in FIG. 59, wherein the flow control device is partially
deployed.
[0088] FIG. 63 is a side view of the flow control device depicted
in FIG. 59, wherein the flow control device is fully retracted.
[0089] FIG. 64 is a side view of the flow control device depicted
in FIG. 59 placed within a bronchial lumen.
[0090] FIG. 65 is a side view of the flow control device depicted
in FIG. 64 fully deployed.
[0091] FIG. 66A shows a perspective view of an umbrella style flow
control device according to one embodiment.
[0092] FIG. 66B shows a perspective view of the flow control device
of FIG. 66 in a contracted state.
[0093] FIG. 66C shows an enlarged view of one embodiment of a
retention strut.
[0094] FIG. 67 shows a perspective view of an umbrella style flow
control device with a retention spring according to another
embodiment.
[0095] FIG. 68 shows a perspective view of an umbrella style flow
control device with curved struts according to another
embodiment.
[0096] FIG. 69 shows a perspective view of an umbrella style flow
control device with pleated membrane according to another
embodiment.
[0097] FIG. 70 shows a perspective view of an umbrella style flow
control device with bended struts according to another
embodiment.
[0098] FIG. 71 shows a bronchoscope deployed within a bronchial
tree of a patient.
[0099] FIG. 72 shows a guidewire deployed within a bronchial tree
of a patient.
[0100] FIG. 73 shows a delivery catheter deployed within a
bronchial tree of a patient over a guidewire.
[0101] FIG. 74 shows a perspective view of a delivery catheter
having an asymmetric, distal tip.
[0102] FIG. 75 shows a perspective view of another embodiment of a
delivery catheter having an asymmetric, distal tip.
[0103] FIG. 76 shows a delivery catheter having a distal curve and
an asymmetric distal tip.
DETAILED DESCRIPTION
[0104] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as is commonly understood by one
of skill in the art to which the invention(s) belong.
[0105] Disclosed are methods and devices for regulating fluid flow
to and from a region of a patient's lung, such as to achieve a
desired fluid flow dynamic to a lung region during respiration
and/or to induce collapse in one or more lung regions. An
identified region of the lung (referred to herein as the "targeted
lung region") is targeted for treatment, such as to modify the air
flow to the targeted lung region or to achieve volume reduction or
collapse of the targeted lung region. The targeted lung region is
then bronchially isolated to regulate airflow into and/or out of
the targeted lung region through one or more bronchial passageways
that feed air to the targeted lung region. As shown in FIG. 1, the
bronchial isolation of the targeted lung region is accomplished by
implanting a flow control device 110 into a bronchial passageway
115 that feeds air to a targeted lung region 120. The flow control
device 110 regulates airflow through the bronchial passageway 115
in which the flow control device 110 is implanted, as described in
more detail below. The flow control device 110 can be implanted
into the bronchial passageway using a delivery system, such as the
delivery system catheter described herein.
Exemplary Lung Regions
[0106] Throughout this disclosure, reference is made to the term
"lung region". As used herein, the term "lung region" refers to a
defined division or portion of a lung. For purposes of example,
lung regions are described herein with reference to human lungs,
wherein some exemplary lung regions include lung lobes and lung
segments. Thus, the term "lung region" as used herein can refer to
a lung lobe or a lung segment. Such lung regions conform to
portions of the lungs that are known to those skilled in the art.
However, it should be appreciated that the term lung region does
necessarily refer to a lung lobe or a lung segment, but can also
refer to some other defined division or portion of a human or
non-human lung.
[0107] FIG. 2 shows an anterior view of a pair of human lungs 210,
215 and a bronchial tree 220 that provides a fluid pathway into and
out of the lungs 210, 215 from a trachea 225, as will be known to
those skilled in the art. As used herein, the term "fluid" can
refer to a gas, a liquid, or a combination of gas(es) and
liquid(s). For clarity of illustration, FIG. 2 shows only a portion
of the bronchial tree 220, which is described in more detail below
with reference to FIG. 4.
[0108] Throughout this description, certain terms are used that
refer to relative directions or locations along a path defined from
an entryway into the patient's body (e.g., the mouth or nose) to
the patient's lungs. The path generally begins at the patient's
mouth or nose, travels through the trachea into one or more
bronchial passageways, and terminates at some point in the
patient's lungs. For example, FIG. 2 shows a path 202 that travels
through the trachea 225 and through a bronchial passageway into a
location in the right lung 210. The term "proximal direction"
refers to the direction along such a path 202 that points toward
the patient's mouth or nose and away from the patient's lungs. In
other words, the proximal direction is generally the same as the
expiration direction when the patient breathes. The arrow 204 in
FIG. 2 points in the proximal direction. The term "distal
direction" refers to the direction along such a path 202 that
points toward the patient's lung and away from the mouth or nose.
The distal direction is generally the same as the inhalation
direction when the patient breathes. The arrow 206 in FIG. 2 points
in the distal direction.
[0109] With reference to FIG. 2, the lungs include a right lung 210
and a left lung 215. The right lung 210 includes lung regions
comprised of three lobes, including a right upper lobe 230, a right
middle lobe 235, and a right lower lobe 240. The lobes 230, 235,
240 are separated by two interlobar fissures, including a right
oblique fissure 226 and a right transverse fissure 228. The right
oblique fissure 226 separates the right lower lobe 240 from the
right upper lobe 230 and from the right middle lobe 235. The right
transverse fissure 228 separates the right upper lobe 230 from the
right middle lobe 135.
[0110] As shown in FIG. 2, the left lung 215 includes lung regions
comprised of two lobes, including the left upper lobe 250 and the
left lower lobe 255. An interlobar fissure comprised of a left
oblique fissure 245 of the left lung 215 separates the left upper
lobe 250 from the left lower lobe 255. The lobes 230, 235, 240,
250, 255 are directly supplied air via respective lobar bronchi, as
described in detail below.
[0111] FIG. 3A is a lateral view of the right lung 210. The right
lung 210 is subdivided into lung regions comprised of a plurality
of bronchopulmonary segments. Each bronchopulmonary segment is
directly supplied air by a corresponding segmental tertiary
bronchus, as described below. The bronchopulmonary segments of the
right lung 210 include a right apical segment 310, a right
posterior segment 320, and a right anterior segment 330, all of
which are disposed in the right upper lobe 230. The right lung
bronchopulmonary segments further include a right lateral segment
340 and a right medial segment 350, which are disposed in the right
middle lobe 235. The right lower lobe 240 includes bronchopulmonary
segments comprised of a right superior segment 360, a right medial
basal segment (which cannot be seen from the lateral view and is
not shown in FIG. 3A), a right anterior basal segment 380, a right
lateral basal segment 390, and a right posterior basal segment
395.
[0112] FIG. 3B shows a lateral view of the left lung 215, which is
subdivided into lung regions comprised of a plurality of
bronchopulmonary segments. The bronchopulmonary segments include a
left apical segment 410, a left posterior segment 420, a left
anterior segment 430, a left superior segment 440, and a left
inferior segment 450, which are disposed in the left lung upper
lobe 250. The lower lobe 255 of the left lung 215 includes
bronchopulmonary segments comprised of a left superior segment 460,
a left medial basal segment (which cannot be seen from the lateral
view and is not shown in FIG. 3B), a left anterior basal segment
480, a left lateral basal segment 490, and a left posterior basal
segment 495.
[0113] FIG. 4 shows an anterior view of the trachea 225 and a
portion of the bronchial tree 220, which includes a network of
bronchial passageways, as described below. The trachea 225 divides
at a distal end into two bronchial passageways comprised of primary
bronchi, including a right primary bronchus 510 that provides
direct air flow to the right lung 210, and a left primary bronchus
515 that provides direct air flow to the left lung 215. Each
primary bronchus 510, 515 divides into a next generation of
bronchial passageways comprised of a plurality of lobar bronchi.
The right primary bronchus 510 divides into a right upper lobar
bronchus 517, a right middle lobar bronchus 520, and a right lower
lobar bronchus 522. The left primary bronchus 515 divides into a
left upper lobar bronchus 525 and a left lower lobar bronchus 530.
Each lobar bronchus, 517, 520, 522, 525, 530 directly feeds fluid
to a respective lung lobe, as indicated by the respective names of
the lobar bronchi. The lobar bronchi each divide into yet another
generation of bronchial passageways comprised of segmental bronchi,
which provide air flow to the bronchopulmonary segments discussed
above.
[0114] As is known to those skilled in the art, a bronchial
passageway defines an internal lumen through which fluid can flow
to and from a lung. The diameter of the internal lumen for a
specific bronchial passageway can vary based on the bronchial
passageway's location in the bronchial tree (such as whether the
bronchial passageway is a lobar bronchus or a segmental bronchus)
and can also vary from patient to patient. However, the internal
diameter of a bronchial passageway is generally in the range of 3
millimeters (mm) to 10 mm, although the internal diameter of a
bronchial passageway can be outside of this range. For example, a
bronchial passageway can have an internal diameter of well below 1
mm at locations deep within the lung.
Stented Flow Control Devices
[0115] As discussed, the flow control device 110 can be implanted
in a bronchial passageway to regulate the flow of fluid through the
bronchial passageway. When implanted in a bronchial passageway, the
flow control device 110 anchors within the bronchial passageway in
a sealing fashion such that fluid in the bronchial passageway must
pass through the flow control device in order to travel past the
location where the flow control device is located. The flow control
device 110 has fluid flow regulation characteristics that can be
varied based upon the design of the flow control device. For
example, the flow control device 110 can be configured to either
permit fluid flow in two directions (i.e., proximal and distal
directions), permit fluid flow in only one direction (proximal or
distal direction), completely restrict fluid flow in any direction
through the flow control device, or any combination of the above.
The flow control device can be configured such that when fluid flow
is permitted, it is only permitted above a certain pressure,
referred to as the cracking pressure. As described in detail below,
the flow control device 110 can also be configured such that a
dilation device can be manually inserted into the flow control
device 110 to vary the flow properties of the flow control device
110.
[0116] FIGS. 5-6 show a first embodiment of a flow control device
110. FIG. 5A shows a perspective view of the device 110, FIG. 5B
shows a perspective, cross-sectional view of the device 110, FIG.
6A shows a plan, side view of the device 110, and FIG. 6B shows a
cross-sectional, plan, side view of the device 110. The flow
control device 110 extends generally along a central axis 605
(shown in FIGS. 5B and 6B) and has a proximal end 602 and a distal
end 604. The flow control device 110 includes a main body that
defines an interior lumen 610 through which fluid can flow along a
flow path that generally conforms to the central axis 605.
[0117] The flow of fluid through the interior lumen 610 is
controlled by a valve member 612 that is disposed at a location
along the interior lumen such that fluid must flow through the
valve member 612 in order to flow through the interior lumen 610,
as described more fully below. It should be appreciated that the
valve member 612 could be positioned at various locations along the
interior lumen 610. The valve member 612 can be made of a
biocompatible material, such as a biocompatible polymer, such as
silicone. The size of the valve member 612 can vary based on a
variety of factors, such as the desired cracking pressure of the
valve member 612.
[0118] The flow control device 110 has a general outer shape and
contour that permits the flow control device 110 to fit entirely
within a body passageway, such as within a bronchial passageway.
Thus, as best shown in FIGS. 5A and 5B, the flow control device 110
has a generally circular shape (when viewed longitudinally along
the axis 605) that will facilitate insertion of the flow control
device into a bronchial passageway. A circular shape generally
provides a good fit with a bronchial passageway, although it should
be appreciated that the flow control device 110 can have other
cross-sectional shapes that enable the device 110 to be inserted
into a bronchial passageway.
[0119] With reference to FIGS. 5-6, the flow control device 110
includes an outer seal member 615 that provides a seal with the
internal walls of a body passageway when the flow control device is
implanted into the body passageway. The seal member 615 is
manufactured of a deformable material, such as silicone or a
deformable elastomer. The flow control device 110 also includes an
anchor member 618 that functions to anchor the flow control device
110 within a body passageway. The configurations of the seal member
615 and the anchor member 618 can vary, as described below.
[0120] As shown in FIGS. 5-6, the seal member 615 is generally
located on an outer periphery of the flow control device 110. In
the embodiment shown in FIGS. 5-6, the seal member includes a
series of radially-extending, circular flanges 620 that surround
the outer circumference of the flow control device 110. The flanges
620 can be manufactured of silicone or other deformable elastomer.
As best shown in FIG. 6B, the radial length of each flange 620
varies moving along the longitudinal length (as defined by the
longitudinal axis 605 in FIG. 6B) of the flow control device 110.
It should be appreciated that the radial length could be equal for
all of the flanges 620 or that the radial length of each flange
could vary in some other manner. For example, the flanges 620 can
alternate between larger and shorter radial lengths moving along
the longitudinal length of the flow control device, or the flanges
can vary in a random fashion. In addition, the flanges 620 could be
oriented at a variety of angles relative to the longitudinal axis
605 of the flow control device. In another embodiment, the radial
length of a single flange could vary so that the circumference of
the flange is sinusoidal about the center of the flange.
[0121] In the embodiment shown in FIGS. 5-6, the seal member 615
includes a cuff 622. As can be seen in the cross-sectional views of
FIGS. 5B and 6B, the cuff 622 comprises a region of the seal member
615 that overlaps on itself so as to form a cavity 623 within the
cuff 622. As described below, the cavity 623 can be used to retain
the anchor member 618 to the seal member 615 of the flow control
device 110. The cuff 622 can function in combination with the
flanges 620 to seal the flow control device to the internal walls
of a bronchial lumen when the flow control device is implanted in a
bronchial lumen, as described below. The cuff 622 can be formed in
a variety of manners, such as by folding a portion of the seal
member 615 over itself, or by molding the seal member 615 to form
the cuff 622.
[0122] As mentioned, the anchor member 618 functions to anchor the
flow control device 110 in place when the flow control device is
implanted within a body passageway, such as within a bronchial
passageway. The anchor member 618 has a structure that can contract
and expand in size (in a radial direction and/or in a longitudinal
direction) so that the anchor member can expand to grip the
interior walls of a body passageway in which the flow control
device is positioned. In one embodiment, as shown in FIGS. 5 and 6,
the anchor member 618 comprises an annular frame 625 that surrounds
the flow control device 110. The frame 625 is formed by a plurality
of struts that define an interior envelope sized to surround the
interior lumen 610.
[0123] As shown in FIGS. 5-6, the struts of the frame 625 form
curved, proximal ends 629 that can be slightly flared outward with
respect to the longitudinal axis 605. When the flow control device
110 is placed in a bronchial lumen, the curved, proximal ends 629
can anchor into the bronchial walls and prevent migration of the
flow control device in a proximal direction. The frame 625 can also
have flared, distal prongs 627 that can anchor into the bronchial
walls and to prevent the device 110 from migrating in a distal
direction when the flow control device 110 is placed in a bronchial
lumen. The frame 625 can be formed from a super-elastic material,
such as Nickel Titanium (also known as Nitinol), such as by cutting
the frame out of a tube of Nitinol or by forming the frame out of
Nitinol wire. The super-elastic properties of Nitinol can result in
the frame exerting a radial force against the interior walls of a
bronchial passageway sufficient to anchor the flow control device
110 in place.
[0124] The struts are arranged so that the frame 625 can expand and
contract in a manner that is entirely or substantially independent
of the rest of the flow control device 110, including the valve
member 612, as described more fully below. In the embodiment shown
in FIGS. 5-6, the frame 625 is attached to the flow control device
110 inside the cavity 623 of the cuff 622. That is, at least a
portion of the frame 625 is positioned inside the cavity 623. The
frame 625 is not necessarily fixedly attached to the cavity.
Rather, a portion of the frame 625 is positioned within the cavity
623 so that the frame 625 can freely move within the cavity, but
cannot be released from the cavity. An attachment means can be used
to attach the opposing pieces of the cuff 622 to one another so
that the frame 625 cannot fall out of the cavity 623. In one
embodiment, the attachment means comprises an adhesive, such as
silicone adhesive, that is placed inside the cavity 623 and that
adheres the opposing pieces of the cuff 622 to one another. In an
alternative embodiment, described below, rivets are used to attach
the opposing pieces of the cuff. It should be appreciated, however,
that different attachment means could be used to secure the frame
625 to the seal member 615. Furthermore, it should be appreciated
that the frame 625 is not necessarily bonded to the seal member
615. In yet another embodiment, the frame 625 can be integrally
formed with the valve protector member 637, described below.
[0125] As mentioned, the valve member 612 regulates the flow of
fluid through the interior lumen 610 of the flow control device
110. In this regard, the valve member 612 can be configured to
permit fluid to flow in only one-direction through the interior
lumen 610, to permit regulated flow in two-directions through the
interior lumen 610, or to prevent fluid flow in either direction.
The valve member 612 is positioned at a location along the interior
lumen 610 so that fluid must travel through the valve member 612 in
order to flow through the interior lumen 610.
[0126] The valve member 612 can be any type of fluid valve, and
preferably is a valve that enables the cracking pressures described
herein. The valve member 612 can have a smaller diameter than the
frame 625 so that compression or deformation of the frame 625 in
both a radial and axial direction will have little or no impact on
the structure of the valve member 612. In the embodiment shown in
FIGS. 5-6, the valve member 612 comprises a duckbill valve that
includes two flaps 631 (shown in FIGS. 5B and 6B) that are oriented
at an angle with respect to one another and that can open and close
with respect to one another so as to form an opening at a lip 801
(FIG. 6B) where the flaps 631 touch one another. The duckbill valve
operates according to a conventional duckbill valve in that it
allows fluid flow in a first direction and prevents fluid flow in a
second direction that is opposed to the first direction. For
example, FIG. 7A shows a schematic side-view of the duckbill valve
in a closed state, wherein the flaps 631 touch one another at the
lip 801. In the closed state, the duckbill valve prevents fluid
flow in a first direction, which is represented by the arrow A in
FIG. 7A. However, when exposed to fluid flow in a second direction
(represented by arrow B in FIG. 7B) that is opposed to the first
direction, the flaps 631 separate from one another to form an
opening between the flaps 631 that permits flow in the second
direction, as shown in FIG. 7B.
[0127] With reference again to FIG. 6B, the valve member 612 is
concentrically contained within the seal member 615. In addition,
at least a portion of the valve member 612 is optionally surrounded
by a rigid or semi-rigid valve protector member 637 (shown in FIGS.
5B and 6B), which is a tubular member or annular wall that is
contained inside the seal member 615. In another embodiment, the
valve protector can comprise a coil of wire or a ring of wire that
provides some level of structural support to the flow control
device. The valve protector 637 can be concentrically located
within the seal member 615. Alternately, the valve member 612 can
be completely molded within the seal member 615 such that the
material of the seal member 615 completely surrounds the valve
protector.
[0128] The valve protector member 637 is optional, although when
present, the valve protector member 637 protects the valve member
612 from damage and can maintain the shape of the flow control
device 110 against compression and constriction to a certain
extent. The valve protection member 637 can also support and
stiffen the flanges 620. The valve protector member 637 can be
manufactured of a rigid, biocompatible material, such as, for
example, nickel titanium, steel, plastic resin, and the like. In
one embodiment, the valve protector member 637 has two or more
windows 639 comprising holes that extend through the valve
protector member, as shown in FIG. 6B. The windows 639 can provide
a location where a removal device, such as graspers or forceps, can
be inserted in order to facilitate removal of the flow control
device 110 from a bronchial passageway.
[0129] The valve protector member 637 can be formed out of a solid
tube of a super-elastic material such as Nitinol. In one
embodiment, the valve protector member 637 is compressible to a
smaller diameter for loading into a delivery catheter. The
compressibility can be achieved by forming the valve protector
member 637 out of a series of struts or by including some open
spaces in the valve protector member 637. The super-elastic
characteristics of Nitinol would allow the valve protector member
637 to be compressed during deployment, yet still allow it to
expand once deployed.
[0130] The seal 615 and/or the frame 625 can contract or expand in
size, particularly in a radial direction. The default state is an
expanded size, such that the flow control device 110 will have a
maximum diameter (which is defined by either the seal 615 or the
frame 625) when the flow control device 110 is in the default
state. The flow control device 110 can be radially contracted in
size during insertion into a bronchial passageway, so that once the
flow control device 110 is inserted into the passageway, it expands
within the passageway.
[0131] In one embodiment, the valve member 612 and frame 625 are
independently enlargeable and contractible. Alternately, the frame
625 can be enlargeable and contractible, while the valve member 612
is not enlargeable and contractible. The independent collapsibility
of the valve member 612 and frame 625 facilitate deployment and
operation of the flow control device 110. The flow control device
110 can be compressed from a default, enlarged state and implanted
in a desired location within a bronchial passageway. Once
implanted, the flow control device 110 automatically re-expands to
anchor within the location of the bronchial passageway. The
independent compression of the frame and valve member reduces the
likelihood of damage to the flow control device 110 during
deployment. Furthermore, the valve can be substantially immune to
the effects of compression of the frame 625. In one embodiment, the
diameter of the frame 625 may collapse as much as 80% without
affecting the valve member 612 so that the valve member 612 will
still operate normally. The flow control device 110 does not have
to be precisely sized for the lumen it is to be placed within. This
affords medical providers with the option of buying smaller volumes
of the flow control device 110 and being able to provide the same
level and scope of coverage for all patients.
[0132] The dimensions of the flow control device 110 can vary based
upon the bronchial passageway in which the flow control device 110
is configured to be implanted. As mentioned, the valve member does
not have to be precisely sized for the bronchial passageway it is
to be placed within. Generally, the diameter D (shown in FIG. 6A)
of the flow control device 110 in the uncompressed state is larger
than the inner diameter of the bronchial passageway in which the
flow control device 110 will be placed. This will permit the flow
control device 110 to be compressed prior to insertion in the
bronchial passageway and then expand upon insertion in the
bronchial passageway, which will provide for a secure fit between
the flow control device 110 and the bronchial passageway.
[0133] FIG. 8 shows the flow control device 110 of FIGS. 5-6
implanted within a bronchial passageway 910 having interior walls
915 that define a lumen of the bronchial passageway 910. As is
known to those skilled in the art, fluids (such as air) can travel
to a region of the lung through the lumen of the bronchial
passageway 910.
[0134] As shown in FIG. 8, the flow control device 110 is implanted
such that one or more of the flanges 620 contact the interior walls
915 to provide a seal that prevents fluid from flowing between the
interior walls 915 and the flanges 620. The cuff 622 can also
provide a seal with the bronchial passageway. At least a portion of
the outermost surface of the cuff 622 sealingly engages the surface
of the interior walls 915. Thus, the flanges 620 and the cuff 622
both provide a seal between the interior walls 915 of the bronchial
passageway 910 and the flow control device 110.
[0135] Thus, fluid must flow through the interior lumen 610 of the
flow control device 110 in order to flow from a proximal side 1301
of the flow control device 110 to a distal side 1302 or vice-versa.
That is, the flanges 620 and cuff 620 form a seal with the interior
wall 915 to prevent fluid from flowing around the periphery of the
flow control device 110, thereby forcing fluid flow to occur
through the internal lumen of the flow control device 110, and
specifically through the valve member 612.
[0136] As shown in FIG. 8, the valve member 612 is oriented such
that it will permit regulated fluid flow in the proximal direction
204, but prevent fluid in a distal direction 206 through the flow
control device 110. The valve member 612 will only permit fluid
flow therethrough when the fluid reaches a predetermined cracking
pressure, as described below. Other types of valve members, or
additional valve members, could be used to permit fluid flow in
both directions or to prevent fluid flow in either direction.
[0137] As shown in FIG. 8, the frame 625 grips the interior wall
915 and presses against the wall 915 with a pressure sufficient to
retain the flow control device 110 in a fixed position relative to
the bronchial passageway. The prongs 627 are positioned such that
they lodge against the interior walls 915 and prevent the flow
control device 110 from migrating in a distal direction 206. The
curved, proximal ends 629 of the frame 625 can lodge against the
interior walls 915 and prevent migration of the flow control device
110 in a proximal direction 204.
[0138] When the flow control device 110 is properly implanted, the
frame 625 does not necessarily return to its original expanded
state after being implanted, but may be deformed and inserted such
that one side is collapsed, or deformed relative to its
pre-insertion shape. The frame 625 preferably has sufficient
outward radial force to maintain the flow control device's position
in the bronchial passageway. Due to the substantially independent
deformation of the frame 625, even if the frame 625 is implanted in
a deformed state, the seal member 615 can still maintain a true and
complete contact with the walls of the bronchial passageway.
[0139] The frame 625 expands to grip the bronchial wall when the
flow control device 110 is implanted in the bronchial passageway.
Thus, the frame 625 can be in at least two states, including an
insertion (compressed) state and an anchoring (expanded or
uncompressed) state. In the insertion state, the frame 625 has a
smaller diameter than in the anchoring state. Various mechanisms
can be employed to achieve the two states. In one embodiment, the
frame 625 is manufactured of a malleable material. The frame 625
can be manually expanded to the anchoring state, such as by
inserting an inflatable balloon inside the frame once the flow
control device 110 is implanted in the bronchial passageway, and
then inflating the balloon to expand the frame beyond the
material's yield point into an interfering engagement with the wall
of the bronchial passageway.
[0140] Another mechanism that can be employed to achieve the
two-state frame 625 size is spring resilience. The insertion state
can be achieved through a preconstraint of the frame 625 within the
elastic range of the frame material. Once positioned in the
bronchial passageway, the frame 625 can be released to expand into
an anchoring state. Constraining tubes or pull wires may achieve
the initial insertion state.
[0141] Another mechanism that can be used to achieve both the
insertion and the anchor states of the frame 625 is the heat
recovery of materials available with alloys, such as certain nickel
titanium alloys, including Nitinol. The transition temperature of
the frame 625 could be below body temperature. Under such a
circumstance, a cool frame 625 can be positioned and allowed to
attain ambient temperature. The unrecovered state of the frame 625
would be in an insertion position with the frame 625 having a
smaller diameter. Upon recovery of the frame material, the frame
625 would expand, such as when the frame achieves a temperature
within the bronchial passageway. Another use of this material may
be through a heating of the device above body temperature with a
recovery temperature zone above that of normal body temperature but
below a temperature which may cause burning. The device might be
heated electrically or through the modulation of a field.
[0142] In one embodiment, the outer diameter of the seal member 615
of the flow control device 110 (in an uncompressed state) is in the
range of approximately 0.20 inches to 0.42 inches at the flanges
620 or at the cuff 622. In one embodiment, the frame 625 has an
outer diameter (in an uncompressed state) in the range of
approximately 0.24 to 0.48 inches. In one embodiment, the flow
control device 110 has an overall length from the proximal end 602
to the distal end 604 of approximately 0.35 inches to 0.52 inches.
It should be appreciated that the aforementioned dimensions are
merely exemplary and that the dimensions of the flow control device
110 can vary based upon the bronchial passageway in which it will
be implanted.
[0143] FIGS. 9-11 show another embodiment of the flow control
device 110. FIG. 9 shows a perspective, cross-sectional view, FIG.
10 shows a side, cross-sectional view, and FIG. 11 shows a front,
plan view of the other embodiment of the flow control device 110.
Unless noted otherwise, like reference numerals and like names
refer to like parts as the previous embodiment. This embodiment of
the flow control device has an anchor member 618 comprising a frame
625 that is disposed in a spaced relationship from the rest of the
flow control device 110. That is, the frame 625 is distally-spaced
from the seal member 615 and the internal lumen 610. As in the
previous embodiment, the flow control device 110 extends generally
along a central axis 605 (shown in FIGS. 9 and 10) and has a main
body that defines an interior lumen 610 through which fluid can
flow along a flow path that generally conforms to the central axis
605. The interior lumen 610 is surrounded by an annular wall 608.
The flow of fluid through the interior lumen is controlled by a
valve member 612. FIG. 9 shows the valve member 612 located at an
end of the interior lumen 610, although it should be appreciated
that the valve member 612 could be positioned at various locations
along the interior lumen 610.
[0144] As best shown in FIG. 11, the flow control device 110 has a
generally circular shape (when viewed longitudinally) that will
facilitate insertion of the flow control device into a bronchial
passageway, although it should be appreciated that the flow control
device 110 can have other cross-sectional shapes that enable the
device to be inserted into a bronchial passageway.
[0145] As best shown in FIGS. 9 and 10, the seal member 615 is
located on an outer periphery of the flow control device 110. In
the embodiment shown in FIGS. 9-11, the seal member includes a
series of radially-extending, circular flanges 620 that surround
the entire outer circumference of the flow control device 110.
[0146] With reference to FIGS. 9 and 10, the anchor member 618 is
shown located on a distal end of the flow control device 110,
although the anchor member 618 can be located at various locations
along the flow control device 110. In the embodiment shown in FIGS.
9-11, the frame 625 is attached to the flow control device 110 by
one or more attachment struts 626 although the frame 625 could also
be attached in other manners.
[0147] In the embodiment shown in FIGS. 9-11, the valve member 612
comprises a septum 630 located at a proximal end of the interior
lumen 610. In a default state, the septum 630 occludes fluid from
flowing through the interior lumen 610 so that the flow control
device 110 shown in FIGS. 9-11 can function as an occluder that
prevents flow in either direction. However, the septum 630 can be
pierced by a dilator device (described below) via a slit 635 in the
septum 630, in order to permit fluid to flow through the interior
lumen 610. The septum 630 is made from a deformable elastic
material.
[0148] The dilator device could comprise a wide variety of devices
that function to dilate the slit 635 in the septum 630 and thereby
provide a passageway across the flow device 110 through which fluid
can flow in one or two directions, depending on the design of the
dilator device. The dilator devices could comprise, for example:
[0149] (1) A suction catheter for aspirating air or fluid distal to
the flow control device. [0150] (2) A long, thin suction catheter
that could be snaked into very distal portions of the isolated lung
region for aspirating fluid or air in the distal portions of the
isolated lung regions. [0151] (3) A short tube to allow free fluid
communication between the occluded region of a bronchial passageway
distal of an implanted flow control device and the region of the
bronchial passageway proximal of the implanted flow control device.
[0152] (4) A tube or other short structure with a one-way valve
mounted inside to allow fluid to be expelled from the isolated
distal lung region (either during normal exhalation or during a
procedure that forces fluid from the isolated, distal lung region)
and to prevent fluid from entering the isolated lung region. [0153]
(5) A catheter with a one-way valve mounted at the tip to allow
fluid to be expelled from the isolated, distal lung region (either
during normal exhalation or during a procedure that forces fluid
from the distal lung segment) and to prevent fluid from entering
the lung segment. [0154] (6) A catheter for instilling a
therapeutic agent, such as antibiotics or other medication, into
the region of the bronchial passageway or lung distal to the flow
control device that has been implanted in the bronchial passageway.
[0155] (7) A catheter for passing brachytherapy sources into the
bronchial passageway distal to the implanted flow control device
for therapeutic reasons, such as to stop mucus production, kill a
pneumonia infection, etc. The brachytherapy source can be
configured to emit either Gamma or Beta radiation. [0156] (8) A
catheter with a semi-permeable distal aspect that circulates a
nitrogen-solvent fluid, which absorbs through osmosis nitrogen
trapped in the lung region distal to the flow control device.
[0157] Thus, the dilator devices described above generally fall
into two categories, including catheter-type dilation devices and
dilation devices comprised of short, tube-like structures. However,
it should be appreciated that flow control device 110 can be used
with various dilation devices that are not limited to those
mentioned above.
[0158] The deployment of the flow control device 110 and use of a
dilator device therewith is described in more detail with reference
to FIGS. 12 and 13. The use of a dilator device is described in the
context of being used with one of the flow control device 110
described herein, although it should be appreciated that the
dilator device can be used with other types of flow control devices
and is not limited to being used with those described herein. FIGS.
12 and 13 show the flow control device 110 of FIGS. 9-11 implanted
within a bronchial passageway 910 having interior walls 915 that
define a lumen of the bronchial passageway 910.
[0159] As shown in FIG. 12, the flow control device 110 is
implanted such that one or more of the flanges 620 contact the
interior walls 915 to provide a seal that prevents fluid from
flowing between the interior walls 915 and the flanges 620. Thus,
fluid must flow through the interior lumen 610 of the flow control
device 110 in order to flow from a proximal side 1301 of the flow
control device 110 to a distal side 1302 or vice-versa.
[0160] It should be appreciated that the relative locations of the
flanges 620 and the frame 625 along the longitudinal axis of the
flow control device can be changed. For example, the flanges 620
could be located on the distal side of the flow control device 110
rather than on the proximal side, and the frame 625 can be located
on the proximal side rather than the distal side. The flow control
device 110 could also be positioned in a reverse orientation in the
bronchial passageway than that shown in FIG. 12. In such a case,
the orientation of the valve member 612 could be arranged to permit
flow in a desired direction, such as in a proximal direction 204
(to allow air flow out of a lung region), a distal direction 206
(to allow air flow into a lung region), or in both directions. The
orientation of the flanges 620 can also be changed based upon how
the flow control device 110 is to be implanted in the bronchial
passageway.
[0161] As discussed, the frame 625 grips the interior wall 915 and
presses against the wall 915 with a pressure sufficient to retain
the flow control device 110 in a fixed position. When in the state
shown in FIG. 12, the flow control device 110 obstructs the
bronchial passageway 910 to prevent fluid from flowing in either
direction through the bronchial passageway 910. In this regard, the
septum 630 can be sufficiently rigid so that the slit 635 does not
open when subjected to expiration and inhalation pressures. As
described further below, other embodiments of the flow control
device 110 can be used to provide regulated fluid flow through the
bronchial passageway 910 in a distal direction, a proximal
direction, or in both the distal and proximal directions.
[0162] With reference now to FIG. 13, the septum 630 can be
mechanically pierced through the slit 635, such as by using a
dilator device comprised of a tube 1010 that dilates the slit 635.
Alternately, the septum 630 can have no slit 635 and the tube 1010
can be used to pierce through the septum 630. In either case, the
septum 630 preferably seals around the outer surface of the tube
1010 in order to prevent fluid flow in the space between the septum
630 and the tube 1010. The tube 1010 is hollow and has an internal
lumen such that the tube 1010 provides an unobstructed fluid flow
passageway between a region of the bronchial passageway 910 distal
of the flow control device 110 and a region of the bronchial
passageway proximal of the flow control device 110.
[0163] Various dilator devices can be inserted through the flow
control device 110 to provide various flow characteristics to the
flow control device, as well as to provide access to the region of
the bronchial passageway located distal of the flow control device
110. In any of the embodiments of the dilation devices and flow
control devices described herein, it should be appreciated that the
dilation device can be pre-loaded into the flow control device 110
prior to deploying the flow control device 110 to the bronchial
passageway. Alternately, the flow control device 110 can be
implanted into the bronchial passageway without the dilation device
and the dilation device inserted into the flow control device 110
after implant of the flow control device 110.
[0164] FIG. 14 shows another embodiment wherein the dilator device
comprises a tube section 1110 that includes a one-way valve 1120
mounted thereon. The one-way valve 1120 can be any type of valve
that permits fluid flow in a first direction but prevents fluid
flow in a second direction opposite to the first direction. For
example, as shown in FIG. 14, the one-way valve 1120 can comprise a
duckbill valve of the type known to those skilled in the art. The
one-way valve 1120 can be positioned such that it allows fluid flow
in an exhalation direction (i.e., proximal direction) 204 but
prohibits fluid flow in an inhalation direction (i.e., distal
direction) 206.
[0165] FIG. 15 shows the flow control device 110 with the septum
630 dilated by a tube section 1110 that includes a one-way valve
1120 mounted thereon. The tube section 1110 has an attachment
structure, such as a flange 1210. A remote actuator, such as a
tether 1215, is attached at a proximal end to the attachment
structure 1210 of the tube section 1110. The tether 1215 can be
formed of a variety of bio-compatible materials, such as any
well-known suture material. The tether 1215 extends in a proximal
direction through the bronchial passageway 910 and through the
trachea (shown in FIG. 2) so that a proximal end of the tether 1215
protrudes through the mouth or nose of the patient. The tether can
be pulled outwardly, which also cause the attached tube will
structure 1110 to be pulled outwardly from the septum 630 by virtue
of the tether's attachment to the tube attachment structure 1210.
The absence of the tube structure 110 would then cause the septum
630 to re-seal so that the flow control device 110 again occludes
fluid flow through the bronchial lumen 910.
[0166] FIG. 16 shows the flow control device 110 implanted in the
bronchial lumen 910, with the septum 630 dilated by a tube section
1110 that includes a one-way valve 1120 mounted thereon. The
one-way valve 1120 fluidly communicates with the internal lumen of
a catheter 1310 at a distal end of the catheter 1310. The catheter
1310 extends in a proximal direction through the bronchial
passageway 910 and through the trachea (shown in FIG. 2) so that a
proximal end of the catheter 1310 protrudes through the mouth or
nose of the patient. The catheter 1310 thereby provides an airflow
passageway for fluid flowing through the one-way valve 1120. Thus,
the catheter 1310 in combination with the one-way valve 1120 and
the flow control device 110 provide a regulated fluid access to the
bronchial passageway 910 at a location distal of the flow control
device 110. The catheter 1310 can thus be used to aspirate fluid
from a location distal of the flow control device 110 by applying a
suction to the proximal end of the catheter 1310, which suction is
transferred to the distal region of the bronchial passageway
through the internal lumen of the catheter 1310, the tube section
1110, and the flow control device 110. The catheter optionally has
one or more vent holes 1320 at a location proximal of the one-way
valve 1120. The vent holes 1320 permit fluid to flow from the
internal lumen of the catheter 1310 into the bronchial passageway
proximal of the flow control device 110.
[0167] FIG. 17 shows the flow control device 110 mounted within the
bronchial passageway 910, with the slit of the septum 630 dilated
by a catheter 1310. A distal end of the catheter 1310 is located
distally of the septum 630. The catheter 1310 extends in a proximal
direction through the bronchial passageway 910 and through the
trachea (shown in FIG. 2) so that a proximal end of the catheter
1310 protrudes through the mouth or nose of the patient. The
catheter 1310 provides an airflow passageway across the flow
control device 110. Thus, the catheter 1310 provides unobstructed
fluid access to the bronchial passageway 910 at a location distal
of the flow control device 110. The catheter 1310 can thus be used
to aspirate fluid from a location distal of the flow control device
110 by applying suction to the proximal end of the catheter 1310,
which suction is transferred to the distal region of the bronchial
passageway through the internal lumen of the catheter 1310. The
catheter 1310 also enables the instillation of therapeutic agents
into the distal side of the flow control device, the passing of
brachytherapy sources to the distal side of the flow control
device, etc, all via the internal lumen of the catheter 1310.
[0168] FIG. 18 shows an alternate embodiment of the flow control
device 110 mounted in a bronchial passageway. This embodiment of
the flow control device 110 is identical to that described above
with reference to FIGS. 9-11, with the exception of the
configuration of the septum 630 and the slit 635. A distal face of
the septum has a taper 1510 located at the slit 635. The taper 1510
functions to reduce the cracking pressure required to open slit 635
so that the cracking pressure of the septum 630 will be lower for
flow moving from the distal side 1302 toward the proximal side 1301
of the flow control device 110, and higher for flow from the
proximal side 1301 to the distal side 1302. The cracking pressure
can be made the same in both directions by eliminating the taper
1510. The cracking pressure can be varied by changing the durometer
of the elastomer, by changing the diameter of the valve, by
changing the length of the slit 635, by changing the angle, depth
or shape of the taper feature 1510, or by changing the thickness of
the valve feature.
[0169] FIGS. 19-21 show another embodiment of the flow control
device 110, which permits fluid flow in a first direction but
prevents fluid flow in a second direction opposite the first
direction. As in the previous embodiments, the flow control device
110 includes a seal member 615, a valve member 612, and an anchor
member 618, as well as an interior lumen 610 formed by an annular
wall 608 (shown in FIG. 21). The annular wall 608 can be made from
Nitinol, injection molded plastic such as polyetheretherketone
(PEEK), or other rigid biocompatible materials. As in the previous
embodiments, the anchor member 618 comprises a frame 625 that is
formed by a plurality of struts that define an interior envelope.
The frame 625 can contract and expand in a radial and longitudinal
direction (relative to the longitudinal axis 1805 shown in FIG.
21). The struts of the frame 625 are arranged so that one or more
of the struts form prongs 1605 having edges that can wedge against
the interior wall of a body passageway to secure an implanted flow
control device against movement within the body passageway. The
anchor member 618 can be manufactured of a shape-memory material,
such as nickel titanium or Nitinol.
[0170] In the embodiment of the flow control device 110 shown in
FIGS. 19-21, the valve member 612 comprises a one-way flap valve
that permits fluid flow in a first flow direction. The flap valve
includes a flap 1610, which can move between a closed position and
an open position (the flap 1610 is shown in an open position in
FIGS. 19-21). In the closed position, the flap 1610 sits within a
seat to block fluid flow through the interior lumen 610. In the
open position, the flap provides an opening into the interior lumen
610 so that fluid can flow through the interior lumen in the first
flow direction.
[0171] As in the previous embodiment, the seal member 615 includes
one or more flanges 620 that can seal against the interior wall of
a body passageway in which the flow control device 110 is
implanted. As shown in FIG. 21, the flanges 625 of the seal member
615 surround the annular wall 608 that forms the interior lumen
610. The flap 1610 and the seal member 615 can be manufactured of
an elastomeric material such as silicone, thermoplastic elastomer,
urethane, etc. The flap 1610 can also be a rigid member that seals
against an elastomer surface of the device 110, or it could be
rigid and lined with an elastomer material. If a rigid flap is
used, then hinges can be used to attach the flap to the device
110.
[0172] At a distal end 1607 of the flow control device 110, the
seal member 615 folds over itself to form an annular cuff 1625. At
least a portion of the frame 625 is positioned within the cuff and
retained therein using retaining members, such as rivets 1630 that
extend through holes in the cuff 1625. The rivets 1630 can be
manufactured of a bio-compatible material, such as silicone
adhesive. The rivets 1630 secure the cuff 1625 to the frame 625 so
as to allow the frame 625 to expand and contract, but to still
firmly capture the frame 625 to the cuff 1625. As best shown in the
section view of FIG. 21, the rivets 1630 extend between opposed
sides of the cuff 1625 to capture but not totally restrain the
frame 625 against expansion or contraction. It should be
appreciated that other attachment means can be used to attach the
frame 625 to the cuff 1625. For example, adhesive can be used as in
the previously-described embodiments.
[0173] Multiple rivets 1630 may be used in any variety of patterns
around the circumference of the cuff 1625. While the rivets 1630
may be short in length such that there is little play between the
folded over region of the cuff 1625 and the portion of the cuff
1625 located within the frame envelope, the rivets 1630 may be
lengthened so that there is substantial play between the
folded-over portion of the cuff 1625 and the interior region of the
cuff 1625. In this manner, the frame 625 can be crumpled or
deformed during deployment, while still allowing sufficient space
for the folded-over region of the cuff 1625 to remain in contact
with the lumen wall, helping to form a seal about the flow control
device 110. Preferably, the frame envelope will conform to the
lumen internal diameter where the flow control device 110 is
implanted. However if there are gaps between the frame envelope and
the lumen interior wall, then the cuff 1625 is capable of providing
the fluid seal.
[0174] In one embodiment, the rivets are installed onto the flow
control device 110 by first sliding the flow control device 110
over a dimpled mandrel. A hole is then drilled through the two
walls of the cuff 1625, and the hole is filled with a glue, such as
silicone adhesive, which will dry within the hole to form the
rivets. The hole in the mandrel can have a dimpled shape that forms
the inside rivet heads, while the outer heads can be formed by
applying excessive adhesive on the outside. The assembly is then
cured in an oven and slid off the mandrel.
[0175] In an alternative embodiment, the cuff 1625 may have a
length such that the cuff 1625 folds over the entire length of the
frame 625. The cuff 1625 is re-attached to the proximal end of the
polymer valve, such that the frame 625 is completely enclosed by
the cuff 1625, so as the frame 625 is implanted within the
bronchial passageway, the loose folds of the polymer skirt can
provide a sealing feature.
[0176] FIGS. 22-24 show yet another embodiment of a flow control
device 110. The flow control device 110 shown in FIGS. 22-24 is
structurally similar to the flow control device 110 described above
with reference to FIGS. 19-21 in that it includes a seal member 615
with a cuff 1625 and flanges 620. The cuff 1625 retains an anchor
member 618 comprised of a frame 625. The flow control device 110 of
FIGS. 22-24 also includes a valve member 612 comprised of a one-way
duckbill valve 1910. The duckbill valve 1910 is configured to
prevent fluid flow from a proximal side to the distal side of the
flow control device 110, and to allow flow at a controlled cracking
pressure from the distal side to the proximal side through a slit
1920 (shown in FIG. 24) in the valve 1910. The cracking pressure of
the duckbill valve 1910 can be adjusted by changing the thickness
of the material used to manufacture the valve 1910, the durometer
of the material, the angle of the duckbill valve, etc. The duckbill
valve can be manufactured a deformable elastomer material, such as
silicone.
[0177] As shown in FIGS. 22-24, the flow control device has valve
dilation member 1930 that facilitates the passage of a dilation
device (such as any of the dilation devices described above)
through the flow control device 110. As was previously described,
the presence of the dilation device in the flow control device 110
can allow the passage of fluid or other treatment devices to or
from the isolated distal lung region when the flow control device
110 is implanted in a bronchial passageway. As best shown in FIGS.
22 and 24, the valve dilation member 1930 defines an interior
region 1935 that has a cone shape having an apex that is adjacent
to an apex of the duckbill valve 1910. The outer surfaces of the
valve dilation member 1920 are not sealed from the surrounding
environment, but are rather exposed. Thus, air pressure of the
surrounding environment is equally distributed on all sides of the
valve dilation member 1930 so that the dilation member 1930 will
not open to fluid flow moving in a distal direction (such as during
normal inspiration), but can be mechanically opened by a dilation
device such as a catheter.
[0178] The flow control device 110 is shown in FIG. 24 with an
optional feature comprised of a valve protector sleeve 1938 that at
least partially surrounds the valve dilation member 1930. The valve
protector sleeve 1938 can be attached to the seal member 615 and
can made of a biocompatible materials such as stainless steel,
Nitinol, etc. In order to ensure that the cracking pressure in the
distal direction is not affected by the addition of the valve
dilation member 1930, the protector sleeve 1938 preferably has one
or more vent holes 1940, which ensure that the pressure is the same
on interior and exterior surfaces of the valve dilation member
1930, as well as on the proximal surface of the duckbill valve
1910. In this way, the cracking pressure in the proximal direction
is also unaffected.
[0179] FIG. 25 shows another embodiment of the flow control device
110 implanted within a bronchial passageway 910. This embodiment is
structurally similar to the embodiment shown in FIGS. 22-24, except
that the anchor member 618 comprises a frame 625 that is distally
disposed on the flow control device 110 in the manner described
above with respect to the embodiments shown in FIGS. 9-18. That is,
the flow control device 110 shown in FIG. 25 does not have a cuff
that attaches the frame to the flow control member. Rather, the
frame 625 is distally separated from the flow control device 110.
As shown in FIG. 25, the flow control device 110 includes a valve
protector sleeve 1938 that is attached to a proximal end of the
valve dilation member 1930. As discussed, the protector sleeve 1938
can have one or more vent holes, which ensure that the pressure is
the same on interior and exterior surfaces of the valve dilation
member 1930.
[0180] FIG. 26 illustrates another embodiment of the flow control
device 110 that is similar to the embodiment shown in FIG. 25.
However, the valve dilation member 1930 has no external support
other than its attachment to the duckbill valve 1910. In addition,
the duckbill valve 1910 is integrally attached to the seal member
615, although it should be appreciated that the duckbill valve and
seal member could also be molded as two separate components and
bonded together. FIG. 27 shows the flow control device 110 of FIG.
26 with a dilator device comprised of a dilation catheter 2415
dilating the flow control device 110 through the valve dilation
member 1930. The dilation catheter 2415 was inserted from the
proximal side of the flow control device 110 for use in passing
fluid to or from the distal side, or for performing other
therapeutic procedures, as described below.
[0181] FIG. 28 shows yet another embodiment of the flow control
device 110. In this embodiment, the duckbill valve 1910 and the
valve dilation member 1930 are surrounded entirely by the annular
wall 608.
[0182] FIG. 29 shows yet another embodiment of the flow control
device 110. The flow control device 110 of FIG. 29 includes a
sealed chamber 2610 that is defined by a space between the duckbill
valve 1910, the valve dilation member 1930, and the annular wall
608. This structure results in a controlled cracking pressure for
flow from the proximal side 602 to the distal side 604 of the flow
control device 110 in addition to a controlled cracking pressure
for flow from the distal side 604 to the proximal side 602. The
cracking pressure in either direction is a function of the pressure
in the sealed chamber 2610, the durometer of the material used to
fabricate the duckbill valve and the valve dilation member, the
thickness of the material, the included angle of the cone portion
of the valve member 1910/valve dilation member 1930, etc. In
addition, this device allows the passage of dilation devices in the
distal direction.
[0183] FIG. 30 shows yet another embodiment of the flow control
device 110. In this embodiment, the flow control device 110 defines
two interior lumens 2710, 2720. The flow control device 110 of FIG.
30 provides for two-way fluid flow, with the interior lumen 2710
providing for fluid flow in a first direction and the interior
lumen 2720 providing for fluid flow in a second direction. There is
a first one-way duckbill valve 2725a mounted in the interior lumen
2710 that allows fluid flow in a proximal direction and a second
duckbill valve 2725b mounted in the interior lumen 2720 that allows
fluid flow in a distal direction. This allows for different
cracking pressures for fluid flow in either direction.
[0184] FIG. 31 shows another embodiment of a flow control device
110 that permits controlled fluid flow in either a proximal
direction or a distal direction. The flow control device 110 has a
single interior lumen 2810. The flow control device 110 includes a
first valve member comprised of a flap valve 2815 that is
configured to permit fluid flow through the lumen 2810 in a first
direction when the valve is exposed to a first cracking pressure. A
second valve 2820 permits fluid flow in a second direction through
the lumen at a second cracking pressure.
Cracking Pressure
[0185] The cracking pressure is defined as the minimum fluid
pressure necessary to open the one-way valve member in a certain
direction, such as in the distal-to-proximal direction. Given that
the valve member of the flow control device 110 will be implanted
in a bronchial lumen of the human lung, the flow control device 110
will likely be coated with mucus and fluid at all times. For this
reason, the cracking pressure of the valve is desirably tested in a
wet condition that simulates the conditions of a bronchial lumen. A
representative way of testing the valve member is to use a small
amount of a water based lubricant to coat the valve mouth. The
testing procedure for a duckbill valve is as follows: [0186] 1.
Manually open the mouth of the valve member, such as by pinching
the sides of the valve together, and place a drop of a dilute water
based lubricant (such as Liquid K-Y Lubricant, manufactured by
Johnson & Johnson Medical, Inc.) between the lips of the valve.
[0187] 2. Wipe excess lubricant off of the valve, and force 1 cubic
centimeter of air through the valve in the forward direction to
push out any excess lubricant from the inside of the valve. [0188]
3. Connect the distal side of the valve to an air pressure source,
and slowly raise the pressure. The pressure is increased from a
starting pressure of 0 inches H2O up to a maximum of 10 inches H2O
over a period of time (such as 3 seconds), and the peak pressure is
recorded. This peak pressure represents the cracking pressure of
the valve.
[0189] The smaller the duckbill valve, the higher the cracking
pressure that is generally required to open the valve. The cracking
pressure of small valves generally cannot be reduced below a
certain point as the valve will have insufficient structural
integrity, as the wall thickness of the molded elastomer is
reduced, and the durometer is decreased. For the flow control
device 110, the lower the cracking pressure is the better the
performance of the implant.
[0190] In one embodiment, the cracking pressure of the valve member
is in the range of approximately 2.6-4.7 inches H2O. In another
embodiment, wherein the valve is larger than the
previously-mentioned embodiment, the cracking pressure of the valve
is in the range of 1.7-4.5 inches H2O. In yet another embodiment,
wherein the valve is larger than the previously-mentioned
embodiment, the cracking pressure of the valve is in the range of
2.0-4.1 inches H2O. In yet another embodiment, wherein the valve is
larger than the previously-mentioned embodiment, the cracking
pressure of the valve is in the range of 1.0-2.7 inches H2O. The
cracking pressure of the valve member can vary based on various
physiological conditions. For example, the cracking pressure could
be set relative to a coughing pressure or a normal respiration
pressure. For example, the cracking pressure could be set so that
it is higher (or lower) than a coughing pressure or normal
respiration pressure. In this regard, the coughing or normal
respiration pressure can be determined based on a particular
patient, or it could be determined based on average coughing or
normal respiration pressures.
Delivery System
[0191] FIG. 32 shows a delivery system 2910 for delivering and
deploying a flow control device 110 to a target location in a
bronchial passageway. The delivery system 2910 includes a catheter
2915 having a proximal end 2916, and a distal end 2917 that can be
deployed to a target location in a patient's bronchial passageway,
such as through the trachea. The catheter 2915 has an outer member
2918 and an inner member 2920 that is slidably positioned within
the outer member 2918 such that the inner member 2920 can slidably
move relative to the outer member 2918 along the length of the
catheter 2915.
[0192] In this regard, an actuation member, such as a two-piece
handle 2925, is located at the proximal end 2916 of the catheter
2915. The handle 2925 can be actuated to move the inner member 2920
relative to the outer member 2918 (and vice-versa). In the
illustrated embodiment, the handle 2925 includes a first piece 2928
and a second piece 2930, which is slidably moveable with respect to
the first piece 2928. The inner member 2920 of the catheter 2915
can be moved relative to the outer member 2918 by slidably moving
the first piece 2928 of the handle 2925 relative to the second
piece 2930. This can be accomplished, for example, by attaching the
proximal end of the catheter inner member 2920 to the first piece
2928 of the handle 2925 and attaching the proximal end of the
catheter outer member 2918 to the second piece 2930. The actuation
member could also take on other structural forms that use other
motions to move the inner member 2920 relative to the outer member
2918. For example, the actuation member could have scissor-like
handles or could require a twisting motion to move the inner member
2920 relative to the outer member 2918.
[0193] As shown in FIG. 32, the handle 2925 also includes a locking
mechanism 2935 for locking the position of the first piece 2928
relative to the second piece 2930 to thereby lock the position of
the inner member 2920 of the catheter 2915 relative to the outer
member 2918. The locking mechanism 2935 can comprise, for example,
a screw or some other type of locking mechanism that can be used to
lock the position of the first piece 2928 of the handle 2925
relative to the second piece 2930.
[0194] The outer member 2918, and possibly the inner member 2920,
can include portions of differing stiffness to allow discrete
portions of the members to bend and deflect more easily than other
portions. In one embodiment, the distal portion of the catheter
2915, for example, the last 10 cm or so just proximal to a
distally-located housing 2940, can be made to have a reduced
bending stiffness. This would allow the distal end 2917 of the
catheter 2915 to bend easily around angles created by branches in
the bronchial tree, and could make placement of flow control
devices easier in more distal locations of the bronchial tree.
[0195] The outer member 2918 of the catheter 2915 could also
include wire reinforcing to improve certain desired
characteristics. The outer member 2918 could be manufactured to
include wire winding or braiding to resist kinking, wire braiding
to improve the ability of the catheter 2915 to transmit torque, and
longitudinal wire or wires to improve tensile strength while
maintaining flexibility, which can improve device deployment by
reducing recoil or "springiness" in the outer member 2918. The
inner member 2920 could also include wire reinforcing, such as wire
winding, wire braiding, or longitudinal wire(s) to resist kinking
and add compressive strength to the inner member 2920.
[0196] With reference still to FIG. 32, a housing 2940 is located
at or near a distal end of the catheter 2915. The housing 2940 is
attached to a distal end of the outer member 2918 of the catheter
2915 but not attached to the inner member 2920. As described in
more detail below, the housing 2940 defines an inner cavity that is
sized to receive the flow control device 110 therein. FIG. 33 shows
an enlarged, perspective view of the portion of the distal portion
of the catheter 2915 where the housing 2940 is located. FIG. 34
shows a plan, side view of the distal portion of the catheter 2915
where the housing 2940 is located. As shown in FIGS. 33 and 34, the
housing 2940 is cylindrically-shaped and is open at a distal end
and closed at a proximal end. The inner member 2920 of the catheter
2915 protrudes through the housing and can be slidably moved
relative to the housing 2940. An ejection member, such as a flange
3015, is located at a distal end of the inner member 2920. As
described below, the ejection member can be used to eject the flow
control device 110 from the housing 2940. The flange 3015 is sized
such that it can be received into the housing 2940. The housing can
be manufactured of a rigid material, such as steel.
[0197] In one embodiment, a tip region 3020 is located on the
distal end of the inner member 2920, as shown in FIGS. 33 and 34.
The tip region 3020 can be atraumatic in that it can have a rounded
or cone-shaped tip that facilitates steering of the catheter 2915
to a desired bronchial passageway location. The atraumatic tip
region 3020 preferably includes a soft material that facilitates
movement of the atraumatic tip region 3020 through the trachea and
bronchial passageway(s). In this regard, the atraumatic tip region
3020 can be manufactured of a soft material, such as polyether
block amide resin (Pebax), silicone, urethrane, and the like.
Alternately, the tip region 3020 can be coated with a soft
material, such as any of the aforementioned materials.
[0198] The inner member 2920 of the catheter 2915 can include a
central guide wire lumen that extends through the entire length of
the catheter 2915, including the atraumatic tip region 3020, if
present. The central guide wire lumen of the inner member 2920 is
sized to receive a guide wire, which can be used during deployment
of the catheter 2915 to guide the catheter 2915 to a location in a
bronchial passageway, as described more fully below.
[0199] In an alternative embodiment of the catheter 2915, the
catheter 2915 could be fitted with a short length of flexible,
bendable guide wire on the distal end of the catheter 2915. The
bendable guide wire could be used to ease the passage of the
catheter 2915 through the bronchial anatomy during deployment of
the catheter 2915. The fixed guide wire could include a soft,
flexible atraumatic tip. The wire portion could be deformed into
various shapes to aid in guiding the catheter 2915 to the target
location. For example, the wire could be bent in a soft "J" shape,
or a "hockey stick" shape, and thus the tip of the guide wire could
be directed to one side or another by rotating the catheter 2915,
thereby allowing the catheter 2915 to be guided into a branch of
the bronchial tree that diverts at an angle away from the main
passage.
[0200] In another embodiment similar to that detailed above, the
distal portion of the delivery catheter 2915, proximal to the
housing 2940, could be made deformable. This would allow the distal
end of the catheter 2915 to be shaped, thus allowing the catheter
2915 to be guided into a bronchial side branch by rotating the
catheter shaft.
[0201] The delivery catheter 2915 could be modified to add a
steerable distal tip function, such as by adding a "pull" wire
located inside a new lumen in the outer member 2918 of the delivery
catheter 2915. The proximal end of the pull wire would be attached
to a movable control that allows tension to be applied to the wire.
The distal end of the wire would be terminated at a retainer
attached to the distal end of the outer member 2918 of the catheter
2915. The distal portion of the catheter 2915 could be manufactured
to be much more flexible than the rest of the catheter 2915, thus
allowing the distal end of the catheter 2915 to bend more easily
than the rest of the catheter 2915. This distal portion could also
have some elastic restoring force so that it will return on its own
to a straight configuration after the tip is deflected or the shape
of the tip is disturbed. When the moveable control is actuated,
thus applying tension to the pull wire, the distal tip or distal
portion of the catheter 2915 will deflect. In addition, other ways
of constructing steering tips for this delivery catheter could be
used.
[0202] An alternate embodiment of the steerable delivery catheter
2915 is one where the distal tip or distal region of the delivery
catheter 2915 is permanently deformed into a bent shape, with the
bent shape corresponding with the greatest desired deflection of
the distal tip. The outer member 2918 of the delivery catheter can
have an additional lumen running along one side, allowing a rigid
or semi-rigid mandrel or stylet to be inserted in the lumen. If the
mandrel is straight, as it is inserted into the side lumen of the
catheter 2915, the deformed tip of the catheter 2915 will
progressively straighten as the mandrel is advanced. When the
mandrel is fully inserted, the outer shaft of the catheter 2915
also becomes straight. The catheter 2915 can be inserted into the
patient in this straight configuration, and the mandrel can be
withdrawn as needed to allow the tip to deflect. In addition, the
mandrel or stylet could be formed into different shapes, and the
catheter 2915 would conform to this shape when the mandrel is
inserted into the side lumen.
[0203] As mentioned, the housing 2940 defines an interior cavity
that is sized to receive the flow control device 110. This is
described in more detail with reference to FIG. 35A, which shows a
cross-sectional view of the housing 2940 with a flow control device
110 positioned within the housing 2940. For clarity of
illustration, the flow control device 110 is represented as a
dashed box in FIG. 35A. The housing 2940 can be sufficiently large
to receive the entire flow control device 110 without any portion
of the flow control device protruding from the housing 2940, as
shown in FIG. 35A.
[0204] Alternately, the housing 2940 can be sized to receive just a
portion of the flow control device 110. For example, the distal end
604 of the flow control device 110 can be shaped as shown in FIG.
35B, but can protrude out of the housing 2940 when the flow control
device 110 is positioned within the housing 2940. In such a case,
the distal end 604 of the flow control device 110 can be made of an
atraumatic material to reduce the likelihood of the distal end 604
damaging a body passageway during deployment.
[0205] Alternately, or in combination with the soft material, the
distal end can be tapered so that it gradually reduces in diameter
moving distally away from the housing, such as is shown in FIG.
35B. The tapered configuration can be formed by a taper in the
shape of the distal edge of the cuff, if the flow control device
110 has a cuff. Or, if the distal edge of the flow control device
110 is a frame, then the frame can be shaped to provide the taper.
As shown in FIG. 35B, the tapered configuration of the distal end
604 of the flow control device 110 can provide a smooth transition
between the outer diameter of the distal end 3020 of the catheter
inner member 2920 and the outer diameter of the distal edge of the
housing 2940. This would eliminate sharp transitions in the
delivery system profile and provide for smoother movement of the
delivery system through the bronchial passageway during deployment
of the flow control device 110. The housing 2940 preferably has an
interior dimension such that the flow control device 110 is in a
compressed state when the flow control device 110 is positioned in
the housing 2940.
[0206] As shown in FIGS. 35A,B, the flow control device 110 abuts
or is adjacent to the flange 3015 of the catheter inner member 2920
when the flow control device is positioned within the housing 2940.
As mentioned, the catheter inner member 2920 is moveable relative
to the housing 2940 and the catheter outer member 2918. In this
regard, the flange 3015 can be positioned to abut a base portion
3215 of the housing 2940 so that the flange 3015 can act as a
detent for the range of movement of the catheter inner member 2920
relative to the catheter outer member 2918.
[0207] As described in more detail below, the catheter 2915 can be
used to deliver a flow control device 110 to a desired bronchial
passageway location. This is accomplished by first loading the flow
control device into the housing 2940 of the catheter 2915. The
distal end of the catheter 2915 is then deployed to the desired
bronchial passageway location such that the housing (and the loaded
flow control device 110) are located at the desired bronchial
passageway location. The flow control device 110 is then ejected
from the housing 2940.
[0208] The ejection of the flow control device 110 from the housing
2940 can be accomplished in a variety of ways. For example, as
shown in FIG. 36A, the catheter 2915 is deployed to a target
location L of a bronchial passageway 3310. The catheter handle 2925
is then actuated to move the outer catheter member 2918 in a
proximal direction relative to the location L, while maintaining
the location of the flow control device 110, inner member 2920, and
flange 3015 fixed with respect to the location L. The proximal
movement of the outer member 2918 will cause the attached housing
2940 to also move in a proximal direction, while the flange 3015
will act as a detent that prevents the flow control device 110 from
moving in the proximal direction. This will result in the housing
2940 sliding away from engagement with the flow control device 110
so that the flow control device 110 is eventually entirely released
from the housing 2940 and implanted in the bronchial passageway, as
shown in FIG. 36B. In this manner, the flow control device 110 can
be implanted at the location L where it was originally positioned
while still in the housing 2940.
[0209] According to another procedure for ejecting the flow control
device 110 from the housing, the catheter 2915 is implanted to a
location L of a bronchial passageway 3310, as shown in FIG. 36A.
The catheter handle 2925 is then actuated to move the inner
catheter member 2920 (and the attached flange 3015) in a distal
direction relative to the location L, while maintaining the
location of the outer member 2918 and the housing 2940 fixed with
respect to the location L. The distal movement of the flange 3015
will cause the flange 3015 to push the flow control device 110 in a
distal direction relative to the location L, while the location of
the housing 2940 will remain fixed. This will result in the flow
control device 110 being ejected from engagement with the housing
2940 so that the flow control device 110 is eventually entirely
released from the housing 2940 and implanted in the bronchial
passageway distally of the original location L, as shown in FIG.
37.
Loader System
[0210] As discussed above, the flow control device 110 is in a
compressed state when it is mounted in the housing 2940 of the
delivery catheter 2915. Thus, the flow control device 110 should be
compressed to a smaller diameter prior to loading the flow control
device 110 into the housing 2940 so that the flow control device
110 can fit in the housing. FIG. 38 shows a perspective view of one
embodiment of a loader system 3510 for compressing the flow control
device 110 to a smaller diameter and for inserting the flow control
device 110 into the delivery catheter housing 2940. The loader
system 3510 can be used to securely hold the catheter housing 2940
in place and to properly align the housing 2940 relative to the
flow control device 110 during insertion of the flow control device
110 into the housing 2940. This facilitates a quick and easy
loading of the flow control device 110 into the housing 2940 and
reduces the likelihood of damaging the flow control device 110
during loading.
[0211] The loader system 3510 includes a loader device 3515 and a
pusher device 3520. As described in detail below, the loader device
3515 is used to compress the flow control device 110 to a size that
can fit into the housing 2940 and to properly align the flow
control device 110 with the housing 2940 during insertion of the
flow control device 110 into the housing 2940. The pusher device
3520 is configured to mate with the loader device 3515 during
loading, as described more fully below. The pusher device 3520 is
used to push the flow control device 110 into the loader device
3515 and into the housing 2940 during loading, as described in more
detail below.
[0212] FIG. 39 is a schematic, cross-sectional view of the loader
device 3515. A loading tunnel 3610 extends entirely through a main
body of the loader device 3515 so as to form a front opening 3615
and an opposed rear opening 3620. The loading tunnel 3610 can have
a circular cross-sectional shape, although it should be appreciated
that the loading tunnel 3610 could have other cross-sectional
shapes. The loading tunnel 3610 has three regions, including a
funnel-shaped loading region 3622, a housing region 3630, and a
catheter region 3635. The loading region 3622 of the loading tunnel
3610 gradually reduces in diameter moving in a rearward direction
(from the front opening 3615 toward the rear opening 3620) so as to
provide the loading region 3622 with a funnel shape. The housing
region 3630 has a shape that substantially conforms to the outer
shape of the catheter housing 2940 so that the catheter housing
2940 can be inserted into the housing region 3630, as described
below. The catheter region 3635 is shaped to receive the outer
member 2918 of the catheter 2915.
[0213] The loader device 3515 can also include a catheter locking
mechanism 3640 comprised of a door 3645 that can be opened to
provide the catheter 2915 with access to the housing region 3630 of
the loading tunnel 3610. The door 3645 can be manipulated to vary
the size of the rear opening 3620 to allow the housing 2940 to be
inserted into the housing region 3630, as described in more detail
below.
[0214] FIG. 40 shows a perspective view of a first embodiment of
the pusher device 3520. Additional embodiments of the pusher device
3520 are described below. The pusher device 3520 has an elongate
shape and includes at least one piston 3710 that is sized to be
axially-inserted into at least a portion of the loading region 3622
of the loader device loading tunnel 3610. The piston 3710 can have
a cross-sectional shape that substantially conforms to the
cross-sectional shape of the loading region 3622 in order to
facilitate insertion of the piston 3710 into the loading region
3622. In one embodiment, the piston has one or more registration
grooves 3715 that conform to the shape of corresponding
registration grooves 3530 (shown in FIG. 38) in the loading tunnel
3610. When the grooves 3715, 3530 are used, the piston 3710 can be
inserted into the loading tunnel 3610 of the loader device 3515 by
aligning and mating the grooves to one another prior to insertion.
The registration grooves 3715, 3530 can be used to ensure that the
piston 3710 can only be inserted into the tunnel in a predetermined
manner.
[0215] With reference to FIGS. 41-44, the loader device 3515 is
used in combination with the pusher device 3520 to compress the
flow control device 110 and insert the flow control device 110 into
the housing 2940 of the catheter 2915. As shown in FIG. 41, the
delivery catheter 2915 is mated to the loader device 3515 such that
the housing 2940 is positioned within the housing region 3630 of
the loader device loading tunnel 3610 and the catheter 2915 is
positioned within the catheter region 3635 of the loading tunnel
3610. When properly mated, the catheter housing 2940 is fixed in
position relative to the loading region 3622 of the loading tunnel
3610. (A process and mechanism for mating the delivery catheter
2915 to the loader device 3515 is described below.) Furthermore,
when the housing 2940 is positioned within the housing region 3630,
the housing interior cavity is open to the loading region 3622 of
the loader device 3515, such that the open end of the housing 2940
is registered with a rear edge of the loading region 3622.
[0216] With reference still to FIG. 41, after the catheter 2915 is
mated with the loader device 3515, the flow control device 110 is
positioned adjacent the front opening 3615 of the loading region
3622 of the loader device 3515. As shown in FIG. 41, the front
opening 3615 is sufficiently large to receive the flow control
device 110 therein without having to compress the size of the flow
control device 110. Alternately, a slight compression of the flow
control device 110 can be required to insert the flow control
device 110 into the opening 3615. The pusher device 3520 is then
positioned such that an end 3810 of the piston 3710 is located
adjacent to the flow control device 110. The housing 2940, flow
control device 110 and the piston 3710 are preferably all axially
aligned to a common longitudinal axis 3711 prior to loading the
flow control device 110 into the housing 2940. However, even if
these components are not all axially aligned, the structure of the
loader device 3515 will ensure that the components properly align
during the loading process.
[0217] With reference now to FIG. 42, the piston 3710 of the pusher
device 3520 is then used to push the flow control device into the
loading region 3622 of the loading tunnel 3610 through the front
opening 3615 in the tunnel. In this manner, the flow control device
110 moves through the loading tunnel 3610 toward the housing 2940.
As this happens, the funnel-shape of the loading region 3622 will
cause the flow control device 110 to be gradually compressed such
that the diameter of the flow control device is gradually reduced
as the flow control device 110 moves toward the housing 2940. The
walls of the loading tunnel 3610 provide an equally balanced
compressive force around the entire circumference of the flow
control device 110 as the flow control device is pushed through the
loading tunnel 3610. This reduces the likelihood of deforming the
flow control device during compression.
[0218] As shown in FIG. 43, as the flow control device is pushed
toward the housing 2940, the flow control device 110 will
eventually be compressed to a size that permits the flow control
device to be pushed into the housing 2940. In one embodiment, the
loading region 3622 of the loading tunnel 3610 reduces to a size
that is smaller than the opening of the housing 2940 so that the
flow control device 110 can slide easily into the housing 2940
without any snags. Alternately, the opening in the housing 2940 can
be substantially equal to the smallest size of the loading region
3622.
[0219] As shown in FIG. 44, the pusher device 3520 continues to
push the flow control device 110 into the loader device 3515 until
the entire flow control device 110 is located inside the housing
2940. The pusher device 3520 can then be removed from the loader
device 3515. The catheter 2915 and the housing 2940 (which now
contains the loaded flow control device 110) can then also be
removed from the loader device 3515.
[0220] As mentioned above, the loader device 3515 includes a
locking mechanism 3640 that is used to lock and position the
catheter 2915 and catheter housing 2940 relative to loader device
3515 during loading of the flow control device 110 into the housing
2940. An exemplary locking mechanism 3640 is now described with
reference to FIGS. 45-48, although it should be appreciated that
other types of locking mechanisms and other locking procedures
could be used to lock and position the catheter 2915 and catheter
housing 2940 relative to loader device 3515 during loading.
[0221] As mentioned, the locking mechanism can comprise a door 3645
that can be moved to facilitate insertion of the catheter housing
2940 into the loader device 3515. Such a locking mechanism 3640 is
described in more detail with reference to FIG. 45, which shows an
exploded, rear, perspective view of the loading member 3515. The
locking mechanism 3640 comprises a door 3645 that is
pivotably-attached to a rear surface of the loader device 3515 by a
first pin 4210. A second pin 4215 also attaches the door 3645 to
the loader device 3515. The second pin extends through an
arc-shaped opening 4220 in the door 3645 to provide a range of
pivotable movement for the door 3645 relative to the loader device
3515, as described more fully below. The rear surface of the loader
device 3515 has an opening 4230 that opens into the housing region
3630 of the loading tunnel 3610 in the loader device 3515. When
mounted on the loader device 3515, the door 3645 can partially
block the opening 4230 or can leave the opening unblocked,
depending on the position of the door 3645. The door 3645 includes
an irregular shaped entry port 4235 through which the catheter 2915
and catheter housing 2940 can be inserted into the opening
4230.
[0222] FIG. 46 shows a rear view of the loader device 3515 with the
door 3645 in a default, closed state. When in the closed state, the
door partially occludes the opening 4230. The entry port 4235
includes a catheter region 4310 that is sized to receive the outer
member 2918 of the catheter 2915. The catheter region 4310 is
aligned with a central axis A of the opening 4230 in the loader
device 3515 when the door 3645 is closed. As shown in FIG. 47, the
door 3645 can be moved to an open position by rotating the door
3645 about an axis defined by the first pin 4210. When the door is
in the open position, the entry port 4230 is positioned such that a
large portion of the entry port 4235 is aligned with the opening
4230 in the loader device 3515 so that the opening 4230 is
unblocked. This allows the housing 2940 of the catheter 2915 to be
inserted into the housing region 3630 through the aligned entry
port 4235 and opening 4230 while the door 3645 is in the open
position, as shown in FIG. 48A. The door 3645 can then be released
and returned to the closed position, such that the door 3645
partially blocks the opening 4230 and thereby retains the housing
2940 within the housing region 3630, as shown in FIG. 48B. The door
3645 can be spring-loaded so that it is biased toward the closed
position.
[0223] As discussed above, during loading of the flow control
device 110, the flow control device 110 is initially positioned
within the loading tunnel 3610 of the loader device 3515. The
initial positioning of the flow control device 110 can be
facilitated through the use of a loading tube 4610, shown in FIG.
49, which is comprised of a handle 4615 and an elongate tube region
4620 having a diameter that can fit within the internal lumen of
the flow control device 110. The elongate tube region 4620 can be
hollow so as to define an interior lumen that can fit over the
front nose region 3020 (shown in FIGS. 33 and 50A) of the catheter
2915. The loading tube 4610 is used as follows: the flow control
device 110 is first mounted on the tube region 4620 by inserting
the tube region 4620 into the interior lumen of the flow control
device 110, such as is shown in FIG. 50A. The tube region 4620 can
optionally have an outer diameter that is dimensioned such that the
tube region fits somewhat snug within the interior lumen of the
flow control device 110 so that the flow control device 110 is
retained on the tube region 4620 through a press-fit.
[0224] As shown in FIG. 50B, the loading tube 4610 is then used to
insert the flow control device 110 over the tip region 3020 and
into the tunnel of the loader device 3515. The handle 4615 can be
grasped by a user to easily manipulate the positioning of the flow
control device 110 relative to the loader device 3515. The loading
tube 4610 can then be removed from the flow control device 110
while keeping the flow control device 110 mounted in the loader
device 3515 in an initial position. The pusher device 3715 is then
used to push the flow control device 110 entirely into the loader
device 3515, as was described above with reference to FIGS.
41-44.
[0225] FIG. 51 shows another embodiment of the pusher device 3520,
which is referred to using the reference numeral 3520a. The pusher
device 3520a includes three separate pistons 3715a, 3715b, 3715c
that each extend radially outward from a center of the pusher
device 3520 in a pinwheel fashion. Each of the pistons 3715a,
3715b, 3715c has a different length L. In particular, the piston
3710a has a length L1, the piston 3615b has a length L2, and the
piston 3710c has a length L3. The pistons 3715a, b, c can be used
in series to successively push the flow control device 110 to
increasingly greater depths into the tunnel of the loader device
110. For example, the piston 3710a can be used first to push the
flow control device 110 to a first depth L1, as shown in FIGS. 52A
and 52B. The piston 3710b can be used next to push the flow control
device 110 to a second depth deeper than the first depth. The third
piston 3710c can finally be used to push the flow control device
110 entirely into the housing. The pistons 3710a, b, c can also
have different diameters from one another. The varying diameters of
the pistons can correspond to the varying diameter of the loading
tunnel in which the piston will be inserted. For example, the
piston with the shortest length can have a larger diameter, as such
as piston will be inserted into the region of the loading tunnel
that has a relatively large diameter. A large diameter will prevent
the piston from being inserted to a location of smaller diameter in
the tunnel. The piston with the longest length can have a smaller
diameter, as such a piston will be inserted deeper into the loading
tunnel, where the diameter is smaller. In this way, the piston
length and diameter can be optimized for insertion into a
particular location of the loading tunnel. In addition, the use of
a pusher device 3520 with pistons of varying length can reduce the
likelihood of pushing the flow control device into the loader
device 3515 at too fast of a rate.
[0226] FIG. 53 shows another embodiment of a loader device, which
is referred to as loader device 3515a, as well as another
embodiment of a corresponding pusher device 3520, which is referred
to using the reference numeral 3520a. The loader device 3515a has
plurality of prongs 5015 that are arranged in an annular fashion so
as to define a funnel-shaped loading region 5010. Thus, the loading
region 5010 is defined by a series of prongs, rather than an
internal tunnel, as in the embodiment of the loader device shown in
FIG. 38. As shown in FIG. 54, the pusher device 3520a can be
inserted into the loading region 5010 of the loader device 3515a to
load the flow control device 110 into the housing of the catheter
2915 when the catheter 2915 is mated with the loader device 3515a.
It should be appreciated that other structures could be used to
define the loading region of the loader device. The pusher device
3520a has a piston with ridges that are dimensioned to mate with
the prongs 5015.
[0227] FIGS. 55-58 show another embodiment of a loader device,
which is referred to as loader device 5510. FIG. 55 shows a front,
plan view of the loader device 5510 in an open state and FIG. 56
shows a side, plan view of the 20 loader device 5510 in an open
state. The loader device 5510 includes a first handle 5515 and a
second handle 5520. The handles 5515, 5520 can be moved with
respect to one another in a scissor fashion. The handles 5515, 5520
are attached to a loader head 5525. A compression mechanism 5530 is
contained in the loader head 5525. The compression mechanism 5530
comprises a series of cams 5549 that are mechanically-coupled to
the handles 5515, 5520, as described in more detail below.
[0228] The compression mechanism 5530 defines a loading tunnel 5540
that extends through the loader head 5525. The cams 5549 have
opposed surfaces that define the shape of the loading tunnel 5540.
In the illustrated embodiment, there are four cams 5549 that define
a rectangular-shaped tunnel looking through the tunnel when the
device in the open state. As described below, when the handles
5515, 5520 are closed, the cams 5549 reposition so that the loading
tunnel takes on a circular or cylindrical shape, as shown in FIG.
57. In the open state, the loading tunnel 5540 can accept an
uncompressed flow control device 110 that has a diameter D. In
alternative embodiments, the compression mechanism 5530 may contain
three, five or more cams 5549.
[0229] With reference to FIG. 56, the loader device 5510 has a
piston mechanism 5545 that includes a piston 5547 that is slidably
positioned in the loading tunnel 5540. The piston 5547 is attached
at an upper end to a lever 5550 that can be used to slide the
piston 5547 through the loading tunnel 5540. In an alternative
embodiment, the piston 5547 is advanced manually, without the use
of the lever 5550, by pushing the piston 5547 into the loading
tunnel 5540.
[0230] As mentioned, the first handle 5515 and the second handle
5520 are movable with respect to one another in a scissor fashion.
In this regard, FIG. 55 shows the handles 5515, 5520 in an open
state. FIG. 57 shows the handles 5515, 5520 in a closed state. The
movement of the handles 5515, 5520 with respect to one another
actuates the compression mechanism 5530 by causing the cams 5549 of
the compression mechanism 5530 to change position and thereby
change the size of the loading tunnel 5540. More specifically, the
diameter D of a flow control device 110 inserted into the loading
tunnel 5540 is larger when the handles 5515, 5520 are open (as
shown in FIG. 55) and smaller when the handles 5515, 5520 are
closed (as shown in FIG. 57). When the handles 5515, 5520 are open,
the size of the loading tunnel 5540 is sufficiently large to
receive a flow control device 110 of diameter D in the uncompressed
state.
[0231] Thus, as shown in FIG. 56, the flow control device 110
(represented schematically by a box 110) can be inserted into the
loading tunnel 5540. Once the flow control device 110 is inserted
into the loading tunnel 5540, the handles 5515, 5520 can be closed,
which will cause the size of the loading tunnel 5540 to decrease.
The decrease in the size of the loading tunnel 5540 will then
compress the diameter of the flow control device 110, which is
contained in the loading tunnel 5540. The flow control device 110
is compressed to a size that will permit the flow control device
110 to fit within the housing 2940 of the catheter delivery system
2910 (shown in FIG. 32). When the handles 5515, 5520 are closed,
the loading tunnel 5540 is at its minimum size. The cams 5549 have
a shape such that when the loading tunnel 5540 is at its minimum
size, the loading tunnel 5540 preferably forms a cylinder. The
loading tunnel 5540 may also form other shapes when the device is
in the closed state, however a cylindrical shape is preferable.
[0232] With reference to FIGS. 56 and 58, the piston 5547 can then
be used to push the flow control device 110 into the housing 2940.
As mentioned, the lever 5550 can be used to slidably move the
piston 5547 through the loading tunnel 5540. As shown in FIG. 56,
when the lever 5550 is in a raised position, the 10 piston 5547 is
only partially inserted into the loading tunnel 5540. As shown in
FIG. 58, the lever 5550 can be moved toward the loader head 5525 to
cause the piston 5547 to slide deeper into the loading tunnel 5540
to a depth such that the piston 5547 will push the flow control
device 110 out of the loading tunnel 5540. The catheter housing
2940 can be placed adjacent to the loading tunnel 5540 so that the
housing 2940 can receive the flow control device 110 as it is
pushed out of the loading tunnel 5540 by the piston 5547. Although
FIGS. 55-58 show the piston mechanism 5545 attached to the loader
5510, it should be appreciated that the piston mechanism 5545 could
be removably attached or a separate device altogether.
[0233] Both the second handle 5520 and the lever 5550 for operating
the piston 5547 are capable of being attached to one or more stops
that allow the user to limit the amount of compression of the
loading tunnel 5540 or to limit the distance the piston 5547 moves
into the loading tunnel 5540. In this manner, the loader 5510 can
be set to compress a flow control device 110 to a particular size
(where the stop corresponds to a desired diameter) and insertion to
a particular length (where the stop corresponds to a movement of
the piston 5547). It should be appreciated that the loader 5510 can
also be configured such that the second handle 5520 can actuate
both the compression mechanics as well as the piston 5547 (or a
piston substitute), such that when the second handle 5520 is closed
to a certain point, the flow control device 110 will be fully
compressed. Continuing to actuate the handle 5520 will cause the
flow control device 110 to be loaded into the housing 2940 of the
catheter 2915.
[0234] The loader 5510 advantageously allows a user to compress and
load the 10 flow control device into the housing 2940 using a
single hand. The user can load the flow control device 110 into the
loading tunnel 5540 of the loader 5510 and then use one hand to
close the handles 5515, 5520, which will cause the loader 5510 to
compress the flow control device 110 to a size that will fit within
the housing 2940. The user can then actuate the piston mechanism
5545 to eject 15 the flow control device 110 out of the loading
tunnel 5540 and into the housing 2940.
Leaf Petal Style Flow Control Devices
[0235] FIG. 59 depicts a leaf petal style flow control device 7000.
The leaf petal style flow control device 7000 is a one-way valve
isolation device, which includes a combined valve and sealing
component 7100 that is conical or cone-like in shape as shown in
FIG. 59. The valve and sealing component 7100 shown in FIG. 59 is
generally conical or cone-like in shape, but other shapes may also
be used. The valve/seal component 7100 is formed of a plurality of
segments 7150 that overlap like the petals of a flower. Each
segment 7150 has a radial edge that is configured to overlap an
adjacent overlapping segment 7150. The radial edge can be connected
or connected to the adjacent overlapping segment 7150.
[0236] The flow control device 7000 also includes a frame 7200 that
is used to position the device 7000 in a bronchial lumen and to
support the valve/seal component 7100. The frame 7200 includes a
central core 7225. A first set of outwardly biased deployable arms
7250 extend distally from the core 7225. A second set of deployable
arms 7275 extends proximally from the core 7225. The second set of
deployable arms 7275 can also be outwardly biased. The leaf petal
style flow control device 7000 also may include a frame retainer
sleeve 7300 that is used to retain outwardly biased deployable arms
7250 and that can be used to radially retract the deployable arms
7250. The frame retainer sleeve 7300 is mounted coaxially over the
frame 7200 and can slide along the length of the frame 7200. The
flow control device 7000 can also include a second sleeve 7400
(shown in a disengaged state for clarity) that can be used to
retain deployable arms 7275.
[0237] The isolation device 7000 is implanted in a bronchial lumen
such that the valve/seal component 7100 engaged the bronchial lumen
wall. Air and liquid can pass between the valve/seal component 7100
and the bronchial lumen wall in the exhalation direction, but when
flow is reversed during inhalation, the valve/seal component 7100
is compressed against the bronchial lumen wall, the segments 7150
are pressed against each other and flow of gas or liquid in the
inhalation direction is prevented.
[0238] Turning to FIG. 60, the valve/seal component 7100 is shown
in an expanded state. The valve/seal component 7100 can be
constructed from a flexible material such as, for example, molded
silicone. Many other flexible materials, such as urethane, can also
be used. The valve/seal component 7100 is formed of a plurality of
segments 7150 that overlap like the petals of a flower. FIG. 60
shows twelve overlapping segments 7150, but the valve/seal
component 7100 can be formed of two, three, four, five, six, seven,
eight, nine, ten, eleven, twelve or more overlapping segments 7150
to accommodate various sized bronchial lumens and to suit varying
needs. With a valve/seal component 7100 formed of individual
overlapping segments 7150, the segments can slide relative to one
another when compressed to smaller diameters, and create a seal
without wrinkles. The device 7000 will still vent fluid easily in
the exhalation direction; however, the overlapping segments 7150
will seal against each other and against the bronchial lumen wall
during inhalation, thus preventing fluid from flowing past the
device 7000 in the inhalation direction. This sealing effect can be
maintained across a range of bronchial lumen diameters.
[0239] Alternately, the individual overlapping segments 7150 may be
joined to each other with foldable sections 7160 as shown in FIG.
60B. The foldable section can include a radial edge that overlaps
with and connects to an adjacent overlapping segment 7150. The
foldable sections 7160 are flexible enough to allow the overlapping
segments 7150 to slide relative to each other in order to maintain
a seal with the bronchial wall at various bronchial wall diameters.
The foldable sections 7160 act as a secondary seal to prevent the
flow of fluid past the device 7000 in the inhalation direction in
the situation where the seal between adjacent overlapping segments
7150 is compromised. The foldable sections 7160 may be formed from
the same material as the overlapping segments 7150, or may be
formed from a different material. The foldable sections may be
thinner or may be formed from a lower durometer material to make
them more flexible or less stiff than the overlapping segments
7150.
[0240] FIG. 60B shows one embodiment of the foldable sections 7160
in the enlarged view 7161. In this embodiment, the foldable section
7160 includes a single fold and a radial edge of the segment 7150
is positioned to overlap with the adjacent segment 7150. The radial
edge 7163 can be free to slide over the adjacent segment 7150 or it
can be attached to the adjacent segment. In another embodiment,
shown in the view 7165 of FIG. 60B, the foldable section 7160
includes two or more folds and the segment 7150 is integrally
attached to an adjacent segment 7150.
[0241] As best shown in FIGS. 61-63, the valve/seal component 7100
is supported by a frame 7200. The frame includes a first set of
outwardly biased or self-expanding deployable arms 7250 that are
used to anchor the device 7000 to the wall of a bronchial lumen.
The deployable arms 7250 thus serve the purpose of preventing
migration of the device 7000 after implantation in the bronchial
lumen in either the inhalation or the exhalation direction. The
frame 7000 also includes a second set of deployable arms 7275,
which may be self-expanding, or outwardly biased as well. The
second set of deployable arms 7275 serve at least two purposes. The
first is to further anchor the device 7000 after implantation in
the bronchial lumen and to prevent the device from migrating in
either the inhalation or the exhalation direction. The second
purpose that the deployable arms 7275 serve is to support the
valve/seal component 7100 that rests against the deployable arms
7275 on the proximal end of the frame 7200 so that the shape of the
valve/seal component 7100 is maintained during inhalation, thus
preventing the valve/seal component 7100 or any of the overlapping
segments 7150 from turning inside out during a rapid inhalation.
The overlapping segments 7150 can be bonded to the deployable arms
7275, or they can rest freely against the deployable arms 7275. The
frame 7200 can have as many deployable arms 7275 as there are
overlapping segments 7150 in the valve/seal component 7100. Thus,
if the valve/seal component 7100 has twelve overlapping segments
7150 as shown in FIGS. 59-65, the frame 7200 can have twelve
deployable arms 7275 extending proximally to support each one of
the overlapping segments 7150. Likewise, if the valve/seal
component 7100 has six overlapping segments 7150, then the frame
7200 can have six deployable arms 7275 to support each of the six
overlapping segments 7150. Thus, the frame can have two, three,
four, five, six, seven, eight, nine, ten, eleven, twelve or more
deployable arms 7275 to match the number of overlapping segments
7150. Alternately, the number of deployable arms 7275 can be
different than the number of overlapping segments 7150.
[0242] The valve/seal component 7100 can be bonded to the core
section 7225 of the frame 7200. The distal ends of the overlapping
segments 7150 can be bonded to the proximal end of the core 7225 of
the frame 7200 in an overlapping configuration. This leaves the
proximal ends of the overlapping segments 7150 free to expand and
contract to different diameters. Other retainer configurations are
also suitable, as long as the valve/seal component 7100 is
supported, and migration in both the inhalation (distal) and the
exhalation (proximal) directions is prevented.
[0243] FIG. 61 shows the flow control device 7000 in a fully
expanded and deployed condition. The retaining sleeve 7300 has been
shifted in a proximal direction to release the outwardly biased
deployable arms 7250.
[0244] FIG. 62 shows the flow control device 7000 in a partially
expanded and deployed condition. In this condition, the flow
control device 7000 can be introduced into the bronchial lumen and
advanced into position to a desired location along the length of
the bronchial lumen. The retainer sleeve 7300 is shown in a
distalmost position along the length of the frame 7200, such that
it is retaining the outwardly-biased deployable arms 7250 in a
contracted condition.
[0245] FIG. 63 shows the flow control device 7000 in a completely
contracted condition. As with the condition shown in FIG. 62, the
flow control device 7000 as shown in FIG. 63 can be introduced into
the bronchial lumen and advanced into position to a desired
location along the length of the bronchial lumen. The retainer
sleeve 7300 is shown in a distalmost position along the length of
the frame 7200, such that it is retaining the outwardly biased
deployable arms 7250. The second retainer sleeve 7400, which is
optional, is shown in a proximalmost position along the length of
the frame 7200, such that it is retaining the deployable arms 7275
and the overlapping segments 7150 of the valve/seal component 7100
in a contracted condition.
[0246] One feature of the flow control device 7000 is removability
after implantation. FIGS. 64 and 65 show the flow control device
7000 with a retainer sleeve 7300 retaining the outwardly biased
deployable arms 7250, and a retainer sleeve 7400 retaining the
deployable arms 7275 and the overlapping segments 7150. Removably
coupled to a receptacle, such as, for example, a hole, in the
retainer sleeve 7300 is an actuation element, such as, for example,
a rigid wire or rod 7600, that extends proximally outside of the
bronchial lumen 7500. Removably coupled to a receptacle, such as,
for example, a hole, in the second retainer sleeve 7400 is a second
actuation element, such as, for example, a rigid wire or rod 7650,
that also extends proximally outside of the bronchial lumen
7500.
[0247] The actuation elements can be used to push or pull the
sleeves 7300, 7400. Once the flow control device 7000 is advanced
into position in the bronchial lumen, the rod 7600 can be pulled or
moved in a proximal direction to slide the sleeve 7300 proximally,
thus releasing the outwardly biased deployable arms 7250. Either
simultaneously, before, or after the outwardly biased deployable
arms 7250 are released, the rod 7650 can be pushed or moved in a
distal direction toward the retainer sleeve 7300, thus releasing
the deployable arms 7275 and the overlapping segments 7150.
Described slightly differently, the motion of moving the two
sleeves towards one another can be created by moving the ends of
the two rods 7600 and 7650 towards each other. In one embodiment,
not shown, this motion can be accomplished by a tool that can hook
onto the two wires and pull them together. In any case, the result
will be a flow control device 7000 that allows exhaled air and
fluid to flow out of the bronchial tube as shown in FIG. 65, but
prevents the flow of air or fluid past the flow control device 7000
in the inhalation direction.
[0248] When it is time to remove the flow control device 7000, the
rod 7600 can be pushed or moved distally to retract the outwardly
biased deployable arms 7250, and the rod 7650 can be pulled or
moved proximally to retract the deployable arms 7275 and the
overlapping segments 7150, thus resulting in the radial collapse of
the flow control device 7000. Once collapsed, the flow control
device 7000 can be pulled out of the bronchial lumen.
[0249] In another embodiment, as shown in FIGS. 61 and 62, the flow
control device 7000 has only one retainer sleeve 7300. A rod, not
shown, is attached to it. In the insertion stage, the retainer
sleeve 7300 retains the outwardly biased deployable arms 7250, and
in the removal stage, the retainer sleeve 7300 is moved proximally
to retain the deployable arms 7275 and the overlapping segments
7150. Alternatively, rather than using a rod, a forceps or other
instrument can be used to grasp the retainer sleeve 7300 and pull
it proximally to retain the deployable arms 7275 and the
overlapping segments 7150 prior to removal.
[0250] The flow control device 7000 can be compressed and
constrained inside the outer tube of a delivery catheter, such as a
catheter that is comprised of an inner tube and an outer tube. The
catheter is located in the desired implant site, and the device is
released by withdrawing the outer tube while holding the inner tube
in position. Once released, the flow control device 7000 expands to
contact and seal against the bronchial lumen. This delivery
catheter can be made small enough to be inserted through the biopsy
channel of a bronchoscope. This way the bronchoscope can be used to
guide the delivery catheter to the target location. The catheter is
then advanced into the target lumen, and the flow control device
7000 released.
Umbrella Style Flow Control Devices
[0251] Like numerals are used to refer to like components in the
umbrella style flow control devices described in this section.
FIGS. 66-70 depict various embodiments of umbrella style flow
control devices. FIGS. 66A and 66B show one embodiment of an
umbrella style flow control device 8000. The flow control device
8000 is an "umbrella" style one-way valve device in that it is
comprised of a frame 8100 with membrane struts 8150 (similar to the
tines of an umbrella) that are covered with a thin elastomeric
membrane 8200. The membrane 8200 is draped over the membrane struts
8150, thus forming the umbrella shape. The membrane 8200 can be
formed of a thin, approximately 0.002 inches thick, polyurethane
sheet material. However, other elastomeric materials, such as
silicone, may be used, and many other thicknesses, both thicker and
thinner than 0.002 inches, may also be used. In one embodiment, the
membrane 8200 has a durometer in the range of about 40 Shore A to
about 100 Shore A. The membrane 8200 may be bonded to the full
length of the membrane struts 8150 running along the inner surface
of the membrane, bonded in selected locations along the strut 8150,
or not bonded at all.
[0252] Each membrane strut 8150 is connected at a distal end to a
distal hub 8300 and at a proximal end to a proximal hub 8400. The
membrane struts 8150 radiate outwardly (i.e. laterally) from the
distal hub 8300 and the proximal hub 8400 to form a ring having a
flexible diameter 8500. The membrane struts 8150 can be spring
biased outwardly (as shown) so that when the flow control device
8000 is implanted in a bronchial lumen, the struts bias and hold
the membrane against the wall of the bronchial lumen.
[0253] In the embodiments shown in FIGS. 66A, 66B, and 67, the
membrane struts 8150 are attached or bonded together at the distal
hub 8300, and again at the proximal hub 8400. When the flow control
device 8000 is compressed for loading, as shown in FIG. 66B, the
two connectors move away from one another to allow the diameter
8500 of the device to decrease and the device 8000 to radially
collapse. When the flow control device 8000 is released or ejected
from the delivery catheter housing and allowed to expand, the
membrane struts 8150 expand to their former shape and press the
membrane 8200 against the bronchial lumen wall. The struts 8150 can
have a stiffness sufficient to tension the membrane when deployed
in the bronchial lumen or sufficient to exert pressure against the
lumen and deform the lumen into a polygonal shape. The membrane can
be sufficiently flexible to seal with the wall of the bronchial
lumen when the membrane is not tensioned by the struts. The flow
control device 8000 can conform to different lumen diameters, and
when placed in smaller diameters, the membrane 8200 may pleat or
fold to seal against the lumen wall during inhalation.
[0254] In another embodiment, not shown, the distal hub 8300 and
proximal hub 8400 may be linked by an axial member, such as a
cable, rod, or shaft, that allows the distance between the two
connectors to be adjusted. In this way, the outer diameter 8500 of
the device may be increased by drawing the two connectors together,
or may be reduced by spreading the connectors father apart.
Accordingly, the flow control device 8000 may be sized to the
bronchial lumen, or if desired, the load of the struts against the
bronchial lumen wall may be increased or decreased. If the
connectors are spread apart, the flow control device 8000 may be
collapsed for removal from the bronchial lumen.
[0255] In one embodiment, the connectors are linked by a threaded
rod (not shown). The rod is captured by the distal hub 8300 but is
free to rotate in the distal hub 8300. The proximal hub 8400 is
threaded such that it will translate along the threaded rod when
the rod is rotated. In this manner, the outer diameter 8500 of the
device 8000 may be varied by rotating the threaded rod in one
direction or the other. This would allow the device 8000 to be
collapsed for delivery without the need for a delivery catheter
with a restraining housing, and could be expanded for a good fit
within the bronchial lumen by rotating the threaded rod.
[0256] Alternatively, the connectors 8300 and 8400 can be linked by
a flexible member (not shown) that is fixed to the distal hub 8300,
and is threaded through the proximal hub 8400 that includes a
locking feature (not shown). In this way, the device can be
expanded by pulling the flexible member through the proximal hub
8400 until the device 8000 expands to the desired diameter, and
then locked in place at the proximal hub 8400. Of course, other
adjustment members and methods are also possible.
[0257] Fluid (gas or liquid) will flow past the flow control device
8000 in the proximal direction, for example during exhalation, by
flowing along the bronchial lumen wall between the membrane struts
8150 by pushing the membrane 8200 away from the wall thus creating
flow channels between each pair of membrane struts 8200. When flow
is reversed, for example during inhalation, the fluid flow in the
distal direction will force the membrane 8200 against the bronchial
lumen wall, thus sealing the passage and preventing flow past the
flow control device 8000. There are also two or more retention
elements comprised of retainer struts 8175 on the distal end, the
proximal end (as shown in FIGS. 66A and 66B), or both ends. The
retention struts 8175 protrude laterally from the frame, For
example, the retention struts 8175 can have a shape, such as an
outwardly-flared shape, that serves to grip the bronchial lumen
wall to prevent migration of the flow control device 8000 in either
the distal or proximal directions. The retainer struts 8175 are
shown in FIG. 66B in a deployed state, but they would be retracted
if loaded into a delivery catheter, returning to their deployed
position only upon release from the delivery catheter. In the
deployed position, the retainer struts 8175 are at an angle of
approximately ninety degrees relative to the connector 8400, though
angles greater than or less than ninety degrees may be used.
[0258] Alternately, the end of the retention struts 8175 may be
formed into the shape shown in FIG. 66C. The retention strut 8175
includes an enlarged section 8177 that can be formed, for example,
by bending or twisting a portion of the retention strut 8175 to
form a foot. With this shape, the depth of penetration of the
distal end 8179 of the retention strut 8175 into the bronchial
lumen wall is limited, and will prevent the distal end 8175 of the
strut from penetrating beyond a predetermined distance into the
lumen wall. In this embodiment, the retention strut end is formed
from the strut material, however other configurations are possible
such as attaching a strut end to the retention strut 8175 that is
formed as a separate component.
[0259] As shown in FIGS. 66A and 66B, the frame 8100 has eight
membrane struts 8100, but it can have two, three, four, five, six,
seven, eight, nine, ten, eleven, twelve, or more struts 8100. The
struts shown in the figures are plain end wires, however other
configurations may be used. The membrane struts 8150 and the
retention struts 8175 (or retention coil 8180) can be made of
nickel-titanium alloy (such as Nitinol) wire. Nitinol can be chosen
for its super-elastic properties so that the flow control device
8000 can be compressed to a small diameter for insertion in a
delivery catheter, yet still expand to its original shape after
deployment. It should be appreciated that many other elastic
materials would work well including stainless steel, plastic,
etc.
[0260] As mentioned above with respect to FIG. 66C, a bend in the
wire end, or a foot could be attached to the retention struts to
prevent migration. In an alternative embodiment, as shown in FIG.
67, the retention element comprises a retention coil 8180 that can
be used instead of retention struts 8175 to prevent migration. The
retention spring can extend proximally from the proximal hub 8400
and can expand to fit different sized bronchial lumens.
[0261] In another embodiment, as shown in FIG. 68, the membrane
struts 8150 have a curved shape where they contact the membrane
8200, rather than the straight shape shown in the embodiments
depicted in FIGS. 66A, 66B, and 67. In this way, the membrane 8200
may conform more closely to the bronchial lumen wall when placed in
bronchial lumens of different diameters.
[0262] In another embodiment as shown in FIG. 69, pleats 8225 are
formed into the membrane 8200 between the membrane struts 8150. In
this embodiment, the pleats 8225 are pre-formed so that the shape
and aspect of the pleats will be controlled in order to improve the
sealing performance of the flow control device 8000. In this
embodiment, the membrane 8200 is pleated when placed in all
diameters of bronchial lumens. It may also be beneficial to extend
the length of the pleats 8225 so that the pleat 8225 is under the
adjacent membrane strut 8150 at all diameters of the device 8000.
This way the membrane strut 8150 will ensure that the pleat 8225 is
held against the bronchial lumen wall.
[0263] In yet another embodiment as shown in FIG. 70, pre-formed
pleats 8225 in the membrane 8200 are supported by bends 8190 in the
membrane struts 8150. The bends 8190 in the membrane struts 8150
hold the pleats 8225 firmly against the wall of the bronchial lumen
after placement, and they ensure that when flow is reversed from
exhalation to inhalation, the membrane seals against the bronchial
lumen wall. As with the other embodiments, the frame 8100 can have
two, three, four, five, six, seven, eight, nine, ten, eleven,
twelve, or more struts 8150, each with a bend 8190. Alternatively,
alternating struts 8150 can have one or more bends 8190. Also, the
membrane 8200 can be bonded to the full length of the membrane
struts 8150, or just to selected locations such as the bends 8190,
or not bonded at all.
[0264] The umbrella style flow control devices depicted in FIGS.
66-70, may be compressed inside a housing of a delivery catheter
for delivery into the target bronchial lumen. As housing may be
retracted, or the flow control device pushed out of the housing, in
order to release the device in the target bronchial lumen and allow
it to expand to contact the lumen wall. Alternatively, they may be
positioned in a bronchial tube with a push catheter 8195 as shown
in FIGS. 66A, 66B, and 68.
Methods of Use
[0265] Disclosed is a method of deploying a flow control device 110
to a bronchial passageway in order to regulate or eliminate airflow
to or from a targeted lung region. The deployed flow control device
110 can eliminate air flow into the targeted lung region and result
in collapse of the targeted lung region. However, the deployed flow
control device 110 need not result in the collapse of the targeted
lung region in order to gain a beneficial effect. Rather, the flow
control device 110 can regulate airflow to and from the targeted
lung region to achieve an improved air flow dynamic, such as by
eliminating airflow into the targeted lung region during
inhalation, but not resulting in collapse. The deployment of the
flow control device 110 can channel or redirect the inhaled air to
a non-isolated, healthier region of the lung, thus improving
ventilation to the healthier lung tissue, and improving
ventilation-perfusion matching in the healthier lung region. The
exhaled air of the targeted lung region can still be vented through
the implanted one-way flow control device 110, and thus the
exhalation dynamics of the targeted lung region need not be
affected by the presence of the flow control device. This can
result in an increase in the efficiency of oxygen uptake in the
lungs.
[0266] The method of deployment and treatment can be summarized
according to the following steps, which are described in more
detail below. It should be appreciated that some of the steps are
optional and that the steps are not necessarily performed in the
order listed below. The steps include: [0267] (a) identifying a
targeted lung region and determining a target location in bronchial
passageway(s) to which the flow control device will be deployed;
[0268] (b) determining the diameter of the target location in the
bronchial passageway(s) and selecting an appropriately sized flow
control device for deploying in the lumen of the bronchial
passageway; as described below, this step is optional, as a flow
control device can be manufactured to span a wide range of
bronchial diameters so that lumen measurement would not be
necessary; [0269] (c) loading the selected flow control device into
a delivery device, such as the delivery catheter described above,
for delivering and deploying the flow control device to the
bronchial passageway; this step is optional, as the flow control
device can be manufactured or obtained pre-loaded in a delivery
device; [0270] (d) positioning the delivery catheter within the
bronchial passageway so that the flow control device is positioned
at the target location in the bronchial passageway; [0271] (e)
deploying the flow control device at the target location in the
bronchial passageway; [0272] (f) removing the delivery device;
[0273] (g) performing one or more procedures on the targeted lung
region and/or allowing reactions to occur in the targeted lung
region as a result of the presence of the flow control device.
[0274] According to step (a), a physician or technician evaluates
the diseased area of a patient's lung to determine the targeted
lung region and then determines the bronchial passageway(s) that
provide airflow to the targeted lung region. Based on this, one or
more target locations of bronchial passageways can be determined to
which one or more flow control devices can be deployed.
[0275] In step (b), the proper size of a flow control device for
insertion into the bronchial passageway is determined. As
mentioned, this step is optional, as a flow control device can be
manufactured to span a wide range of bronchial diameters so that
lumen measurement would not be necessary. It should be appreciated
that a precise match between the size of the flow control device
110 and the lumen of the bronchial passageway is not required, as
the compressibility and expandability of the flow control device
110 provides a variation in size. In one embodiment, the flow
control device is selected so that its size is slightly larger than
the size of the bronchial passageway.
[0276] Various methods of measuring a bronchial passageway diameter
are known and understood in the art. For example, a balloon having
a known ratio of inflation to diameter can be used, thus allowing
an accurate way of determining a bronchial passageway diameter. A
loop or measuring device such as a marked linear probe may also be
used. The diameter could also be measured using a high resolution
computerized tomography (CT) scan. Even an "eye-ball" estimate
could also be sufficient, wherein the sizing is done visually
without using a measuring tool, depending on the skill of the
physician.
[0277] In step (c), the flow control device is loaded onto a
delivery system, such as the delivery system 2910 comprised of the
catheter 2915 that was described above with reference to FIG. 31.
If the delivery system 2910 is used, the flow control device 110 is
loaded into the housing 2940 at the distal end of the catheter
2915, such as by using the loader system 3510, described above.
Alternately, the flow control device 110 can be loaded into the
housing 2940 by hand. As mentioned, the loading step can be
optional, as the flow control device 110 can be manufactured or
obtained with the flow control device pre-loaded. It should be
appreciated that other delivery systems could also be used to
deliver the flow control device to the bronchial passageway.
[0278] In step (d), the delivery catheter is inserted into the
bronchial passageway so that the flow control device 110 is
positioned at a desired location in the bronchial passageway. This
can be accomplished by inserting the distal end of the delivery
catheter 2915 into the patient's mouth or nose, through the
trachea, and down to the target location in the bronchial
passageway. The delivery of the delivery catheter 2915 to the
bronchial passageway can be accomplished in a variety of manners.
In one embodiment, a bronchoscope is used to deliver the delivery
catheter 2915. For example, with reference to FIG. 71, the delivery
catheter 2915 can be deployed using a bronchoscope 5210, which in
an exemplary embodiment has a steering mechanism 5215, a shaft
5220, a working channel entry port 5225, and a visualization
eyepiece 5230. The bronchoscope 5210 has been passed into a
patient's trachea 225 and guided into the right primary bronchus
510 according to well-known methods.
[0279] It is important to note that the distal end of the
bronchoscope is preferably deployed to a location that is at least
one bronchial branch proximal to the target bronchial lumen where
the flow control device will be implanted. If the distal end of the
bronchoscope is inserted into the target bronchial lumen, it is
impossible to properly visualize and control the deployment of the
flow control device in the target bronchial lumen. For example, if
the bronchoscope is advance into the right primary bronchus 510 as
shown in FIG. 71, the right upper lobar bronchi 517 can be
visualized through the visualization eyepiece of the bronchoscope.
The right upper lobar bronchi 517 is selected as the target
location for placement of a flow control device 110 and the distal
end of the bronchoscope is positioned one bronchial generation
proximal of the bronchial passageway for the target location. Thus,
the distal end of the bronchoscope is deployed in the right primary
bronchus 510. The delivery catheter 2915 is then deployed down a
working channel (not shown) of the bronchoscope shaft 5220 and the
distal end 5222 of the catheter 2915 is guided out of the distal
tip of the bronchoscope and advanced distally until the delivery
system housing containing the compressed flow control device is
located inside the lobar bronchi 517.
[0280] The steering mechanism 5215 can be used to alter the
position of the distal tip of the bronchoscope to assist in
positioning the distal tip of the delivery catheter 5222 such that
the delivery catheter housing can be advanced into the desired
bronchi (in this case the lobar bronchi 517). It should be
appreciated that this technique can be applied to any desired
delivery target bronchi in the lungs such as segmental bronchi, and
not just the lobar bronchi.
[0281] Alternately, the delivery catheter 2915 can be fed into the
bronchoscope working channel prior to deploying the bronchoscope to
the bronchial passageway. The delivery catheter 2915 and the
bronchoscope 5210 can then both be delivered to the bronchial
passageway that is one generation proximal to the target passageway
as a single unit. The delivery catheter can then be advanced into
the target bronchi as before, and the flow control device 110
delivered.
[0282] In another embodiment, the inner member 2920 of the delivery
catheter 2915 has a central guidewire lumen, so that the catheter
2915 is deployed using a guidewire that guides the catheter 2915 to
the delivery site. In this regard, the delivery catheter 2915 could
have a well-known steering function, which would allow the catheter
2915 to be delivered with or without use of a guidewire. FIGS.
60-61 illustrate how the catheter 2915 can be used to deliver the
flow control device 110 using a guidewire.
[0283] FIG. 72 illustrates a first step in the process of deploying
a delivery catheter 2915 to a target location using a guidewire. A
guidewire 5310 is shown passed down the trachea 225 so that the
distal end of the guidewire 5310 is at or near the target location
5315 of the bronchial passageway. The guidewire 5310 can be
deployed into the trachea and bronchial passageway through free
wiring, wherein the guidewire 5310 with a steerable tip is
alternately rotated and advanced toward the desired location.
Exchange wiring can also be used, wherein the guidewire 5310 is
advanced down the working channel of a bronchoscope that has been
previously deployed. The bronchoscope can then be removed once the
guidewire is at the desired location.
[0284] In any event, after the guidewire 5310 is deployed, the
distal end of the delivery catheter 2915 is back loaded over the
proximal end of the guidewire 5310. The delivery catheter 2915 is
advanced along the guidewire 5310 until the housing 2940 on the
distal end of the delivery catheter 2915 is located at the target
location 5315 of the bronchial passageway. The guidewire 5310
serves to control the path of the catheter 2915, which tracks over
the guidewire 5310, and insures that the delivery catheter 2915
properly negotiates the path to the target site. Fluoroscopy can be
helpful in visualizing and insuring that the guidewire 5310 is not
dislodged while the delivery catheter is advanced. As shown in FIG.
73, the delivery catheter 2915 has been advanced distally over the
guidewire 5310 such that the housing 2940 at the distal end of the
delivery catheter 5310 has been located at the target location 5315
of the bronchial passageway. The flow control device 110 is now
ready for deployment.
[0285] Visualization of the progress of the distal tip of the
delivery catheter 2915 can be provided by a bronchoscope that is
manually advanced in parallel and behind the delivery catheter
2915. Visualization or imaging can also be provided by a fiberoptic
bundle that is inside the inner member 2920 of the delivery
catheter 2915. The fiberoptic bundle could be either a permanent
part of the inner member 2920, or could be removable so that it is
left in place while the housing 2940 is maneuvered into position at
the bronchial target location, and then removed prior to deployment
of the flow control device 110. The removable fiberoptic bundle
could be a commercial angioscope which has fiberoptic lighting and
visualization bundles, but unlike a bronchoscope, it is not
steerable.
[0286] Passage of the delivery catheter through tortuous bronchial
anatomy can be accomplished or facilitated by providing the
delivery catheter 2915 with a steerable distal end that can be
controlled remotely. For example, if the distal end of the catheter
2915 could be bent in one direction, in an angle up to 180 degrees,
by the actuation of a control on the handle 2925, the catheter 2915
could be advanced through the bronchial anatomy through a
combination of adjusting the angle of the distal tip deflection,
rotating the delivery catheter 2915, and advancing the delivery
catheter 2915. This can be similar to the way in which many
bronchoscopes are controlled.
[0287] It can be advantageous to use a specific design of a
guidewire that configured to allow the delivery catheter 2915 to
navigate the tortuous bronchial anatomy with minimal pushing force,
and minimal hang-ups on bronchial carinas.
[0288] A guidewire can be constructed of a stainless steel core
which is wrapped with a stainless steel coil. The coil is coated
with a lubricous coating, such as a Polytetrafluoroethylene (PTFE)
coating, a hydrophilic coating, or other lubricious coating. The
guidewire can be in the range of, for example, around 180 cm in
length and 0.035'' inch in overall diameter, though other lengths
and diameters are possible. A proximal portion of the wire core can
be constructed so that after winding the outer coil onto the core,
it is as stiff as possible but still allows for easy placement in
the lungs using an exchange technique with a bronchoscope. The
distal portion, such as the distal-most 2-5 cm, of the wire core
may be made with a more flexible construction in order to create an
atraumatic tip to the wire. This atraumatic nature of the distal
tip can be enhanced by adding a "modified j" tip. A portion of the
wire (such as about 3 cm) between the distal and proximal sections
could provide a gradual stiffness transition so that the guidewire
does not buckle when placed in the lung anatomy.
[0289] By having a relatively short atraumatic section, the
clinician can place the guidewire in the target location of the
bronchial passageway with only a small length of guidewire
extending distally of the target passageway. This will minimize the
probability of punctured lungs and other similar complications. The
clinician can then utilize the stiff nature of the proximal portion
of the guidewire to facilitate placing the delivery catheter all
the way to the target bronchial passageway.
[0290] With reference again to the method of use, in step (e), the
flow control device 110 is deployed at the target location of the
bronchial passageway. The flow control device 110 is deployed in
the bronchial lumen such that the flow control device 110 will
provide a desired fluid flow regulation through the bronchial
lumen, such as to permit one-way fluid flow in a desired direction,
to permit two-way fluid flow, or to occlude fluid flow.
[0291] The deployment of the flow control device 110 can be
accomplished by manipulating the two-piece handle 2925 of the
catheter 2915 in order to cause the housing 2940 to disengage from
the flow control device 110, as was described above with reference
to FIGS. 36 and 37. For example, the handle can be actuated to
withdraw the outer member of the catheter relative to the inner
member, which will cause the housing 2940 to move in a proximal
direction while the flange on the inner member retains the flow
control device 110 against movement within the bronchial
passageway. By withdrawing the housing instead of advancing the
flange, the flow control device 110 can be deployed in the
bronchial passageway at the target location, rather than being
pushed to a more distal location. After the flow control device 110
has been deployed at the target site in the bronchial passageway,
the delivery devices, such as the catheter 2915 and/or guidewire,
is removed in step (f).
[0292] Either all or a portion of the flow control device 110 can
be coated with a drug that will achieve a desired effect or
reaction in the bronchial passageway where the flow control device
110 is mounted. For example, the flow control device 110 can be
coated with any of the following exemplary drugs or compounds:
[0293] (1) Antibiotic agents to inhibit growth of microorganisms
(sirolimus, doxycycline, minocycline, bleomycin, tetracycline,
etc.) [0294] (2) Antimicrobial agents to prevent the multiplication
or growth of microbes, or to prevent their pathogenic action.
[0295] (3) Anti-inflammatory agents to reduce inflammation. [0296]
(4) Anti-proliferative agents to treat cancer. [0297] (5) Mucolytic
agents to reduce or eliminate mucus production. [0298] (6)
Analgesics or pain killers, such as Lidocane, to suppress early
cough reflex due to irritation. [0299] (7) Coagulation enhancing
agents to stop bleeding. [0300] (8) Vasoconstrictive agents, such
as epinephrine, to stop bleeding. [0301] (9) Agents to regenerate
lung tissue such as all trans-retinoic acid. [0302] (10) Steroids
to reduce inflammation. [0303] (11) Gene therapy for parenchymal
regeneration. [0304] (12) Tissue growth inhibitors (paclitaxel,
rapamycin, etc.). [0305] (13) Sclerosing agents, such as
doxycycline, minocycline, tetracycline, bleomycin, cisplatin,
doxorubicin, fluorouracil, interferon-beta, mitomycin-c,
Corynebacterium parvum, methylprednisolone, and talc. [0306] (14)
Agents for inducing a localized infection and scar, such as a weak
strain of Pneumococcus. [0307] (15) Fibrosis promoting agents, such
as a polypeptide growth factor (fibroblast growth factor (FGF),
basic fibroblast growth factor (bFGF), transforming growth
factor-beta (TGF-.beta.)). [0308] (16) Pro-apoptopic agents such as
sphingomyelin, Bax, Bid, Bik, Bad, caspase-3, caspase-8, caspase-9,
or annexin V. [0309] (17) PTFE, parylene, or other lubricous
coatings. [0310] (18) In addition, the retainer and other metal
components could be irradiated to kill mucus production or to
create scar tissue.
[0311] It should be appreciated that the aforementioned list is
exemplary and that the flow control device 110 can be coated with
other types of drugs or compounds.
[0312] After the flow control device 110 is implanted, the targeted
lung region can be allowed to collapse over time due to absorption
of trapped gas, through exhalation of trapped gas through the
implanted flow control device 110, or both. As mentioned, collapse
of the targeted lung region is not necessary, as the flow control
device 110 can be used to simply modify the flow of air to the
targeted lung region. Alternately, or in addition to, allowing the
targeted lung region to collapse over time, one or more methods of
actively collapsing the lung segment or segments distal to the
implanted flow control device or devices can be performed. One
example of an active collapse method is to instill an absorbable
gas through a dilation catheter placed through the flow control
device and very distally in the targeted lung region, while at the
same time aspirating at a location proximal to the flow control
device 110 with a balloon catheter inflated in the proximal region
of the flow control device 110. In another example, oxygen is
instilled into the distal isolated lung region through a catheter
that dilates the flow control device 110. When this is complete, a
method of actively collapsing the isolated lung region could be
performed (such as insuflating the pleural space of the lung) to
drive the gas present in the isolated lung region out through the
implanted flow control device 110. One example of performing active
collapse without a dilation device present would be to insert a
balloon into the pleural space and inflate it to force gas or
liquid out of the isolated lung region and collapse the lung.
[0313] The following is a list of methods that can be used to
actively collapse a targeted lung region that has been bronchially
isolated using a flow control device implanted in a patient's
bronchial passageway: [0314] (1) The patient is allowed to breathe
normally until air is expelled from the lung segment or segments
distal to the device. [0315] (2) The targeted lung region is
aspirated using a continuous vacuum source that can be coupled to a
proximal end of the delivery catheter, to a dilator device that
crosses the flow control device, or to a balloon catheter placed
proximally to the implanted flow control device. [0316] (3) Fluid
is aspirated from the targeted lung region using a pulsed (rather
than continuous) vacuum source. [0317] (4) Fluid is aspirated from
the targeted lung region using a very low vacuum source over a long
period of time, such as one hour or more. In this case, the
catheter may be inserted nasally and a water seal may control the
vacuum source. [0318] (5) The targeted lung region can be filled
with fluid, which is then aspirated. [0319] (6) Insufflate pleural
space of the lung with gas through a percutaneously placed needle,
or an endobronchially placed needle, to compress the lung. [0320]
(7) Insert a balloon into the pleural space and inflate the balloon
next to targeted lung region. [0321] (8) Insert a percutaneously
placed probe and compress the lung directly. [0322] (9) Insert a
balloon catheter into the bronchial passageway leading to adjacent
lobe(s) of the targeted lung region and over-inflate the adjacent
lung segment or segments in order to collapse the targeted lung
region. [0323] (10) Fill the pleural space with sterile fluid to
compress the targeted lung region. [0324] (11) Perform external
chest compression in the region of the target segment. [0325] (12)
Puncture the targeted lung region percutaneously and aspirate
trapped air. [0326] (13) Temporarily occlude the bronchus leading
to the lower lobe and/or middle lobe as the patient inhales and
fills the lungs, thus increasing compression on the target lung
segment or segments during exhalation. [0327] (14) Induce coughing.
[0328] (15) Encourage the patient to exhale actively with pursed
lip breathing. [0329] (16) Use an agent to clear or dilate the
airways including mucolytics, bronchodilators, surfactants,
desiccants, solvents, necrosing agents, sclerosing agents,
perflourocarbons, or absorbents, then aspirate through the flow
control device using a vacuum source. [0330] (17) Fill the isolated
lung region with 100% oxygen (O2) or other easily absorbed gas.
This could be accomplished using a dilation device, such as a
catheter, that is passed through an implanted flow control device.
The oxygen would dilute the gas that is in the isolated lung region
to thereby raise the oxygen concentration, causing any excess gas
to flow out of the isolated lung region through the flow control
device or dilation device. The remaining gas in the isolated lung
region would have a high concentration of oxygen and would be more
readily absorbed into the blood stream. This could possibly lead to
absorption atelectasis in the isolated lung region. The remaining
gas in the isolated lung region could also be aspirated back
through the dilation device to aid in collapse of the isolated lung
region.
[0331] Optionally, a therapeutic agent could be instilled through a
dilator device (such as was described above) that has been passed
through the flow control device deployed at a target site in the
patient's bronchial lumen. The therapeutic agent is instilled into
the bronchial lumen or lumens distal to the implanted flow control
device. Alternately, brachytherapy source or sources could be
inserted through the dilator device and into the lumen or lumens
distal to the flow control device to reduce or eliminate mucus
production, to cause scarring, or for other therapeutic
purposes.
[0332] The patient's blood can be de-nitrogenated in order to
promote absorption of nitrogen in trapped airways. Utilizing any of
the devices or methods above, the patient would either breath
through a mask or be ventilated with heliox (helium-oxygen mixture)
or oxygen combined with some other inert gas. This would reduce the
partial pressure of nitrogen in the patient's blood, thereby
increasing the absorption of nitrogen trapping in the lung spaces
distal to the implanted flow control device.
[0333] As mentioned, one method of deflating the distal lung volume
involves the use of pulsed vacuum instead of continuous vacuum.
Pulsatile suction is defined as a vacuum source that varies in
vacuum pressure from atmospheric pressure down to -10 cm H.sub.2O.
The frequency of the pulse can be adjusted so that the collapsed
bronchus has time to re-open at the trough of the suction wave
prior to the next cycle. The frequency of the pulse could be fast
enough such that the bronchus does not have time to collapse at the
peak of the suction wave prior to the next cycle. The suction force
could be regulated such that even at the peak suction, the negative
pressure is not low enough to collapse the distal airways. The
frequency of the pulsatile suction could be set to the patient's
respiratory cycle such that negative pressure is applied only
during inspiration so that the lung's tethering forces are exerted
keeping the distal airways open.
[0334] One possible method of implementing this described form of
pulsatile suction would be to utilize a water manometer attached to
a vacuum source. The vacuum regulator pipe in the water manometer
could be manually or mechanically moved up and down at the desired
frequency to the desired vacuum break point (0 to -10 cm). This
describes only one of many methods of creating a pulsatile vacuum
source.
[0335] At any point, the dilator device (if used) can be removed
from the flow control device. This can be accomplished by pulling
on a tether attached to the dilator device (such as was shown in
FIG. 15), pulling on a catheter that is attached to the dilator
device, or grasping the dilator device with a tool, such as
forceps. After removal of the dilator device, another dilator
device could be used to re-dilate the flow control device at a
later time.
Asymmetric Delivery Catheter
[0336] During deployment of the flow control device 110 using an
over-the-wire delivery catheter, navigating the delivery catheter
2915 past the lungs' carinae can frequently present difficulties,
as the housing 2940 can often get stuck against the sharp edge of a
carina or will not properly align with the ostium of a target
bronchus. If the housing 2940 gets stuck, it can be very difficult
to advance the catheter 2915 any further or to achieve a more
distal placement.
[0337] In order to ease the navigation of the housing past carinae
and into the ostium of a target bronchus, the tip region 3020 of
the catheter inner member 2920 can have a rib or elongate
protrusion 5810 extending in one direction radially so as to
provide the tip region 3020 with an asymmetric shape, such as is
shown in FIGS. 74 and 75. The tip region 3020 is asymmetric with
respect to a central longitudinal axis 6210 of the catheter 2915.
The protrusion 5810 can extend radially, for example, as far as the
outer diameter of the housing 2940. The protrusion 5810 extends
only in one direction in order to minimize the perimeter of the tip
region 3020, which facilitates passing the tip region 3020 through
the central lumen of the flow control device 110. The protrusion
5810 can be made of a solid material (such as shown in FIG. 74) or,
alternately, the protrusion 5810 can be hollow (such as shown by
reference numeral 6310 in FIG. 75) in order to allow some
compressive compliance. The compliance would be such that the
protrusion 5810 does not compress when pushed against lung tissue
but would compress when it is pulled through the flow control
device 110 or pushed into the lumen of a loading device.
[0338] By having the protrusion 5810 be compliant, the protrusion
5810 could be tall enough to extend to the outside diameter of the
housing but then compress to a smaller size that would fit through
the flow control device lumen or the loading device. Alternatively,
two or more radially spaced protrusions could be added to the tip
region 3020 of the catheter 2915 to provide a smooth transition
between the tip region 3020 and the housing 2940. The protrusions
5810 could be made hollow or very soft so that they would easily
collapse when inserted through the flow control device 110.
[0339] As mentioned, the outer shaft 2918 of the delivery catheter
2915 could be shaped to contain a curve, biasing the whole catheter
in one direction. In one embodiment, shown in FIG. 76, the curve
6010, if present, is contained within a single plane and is limited
to a portion, such as 3 inches, of catheter length just proximal to
the housing 2940. The plane of the outer shaft curve could be
coincident with the plane containing the protrusion 5810 on the tip
region 3020. In this manner, the curve in the outer shaft could be
used to align the delivery catheter 2915 so that as the catheter
2915 is traveling over a curved guidewire it will have the
protrusion 5810 always facing outward relative to the curve. Due to
the three dimensional nature of the bronchial tree in the lungs, a
useful geometry of the shaped end of the catheter may be a complex
curve that bends in three dimension to match the lung anatomy,
rather than being a simple curve in single plane (two dimensions).
In addition, the proximal end of the catheter 2915 might be shaped
to conform to the curve commonly found in endotracheal tubes to
ease delivery if the patient is under general anesthesia and is
being ventilated.
[0340] Although embodiments of various methods and devices are
described herein in detail with reference to certain versions, it
should be appreciated that other versions, embodiments, methods of
use, and combinations thereof are also possible. Therefore the
spirit and scope of the appended claims should not be limited to
the description of the embodiments contained herein.
* * * * *