U.S. patent application number 11/271211 was filed with the patent office on 2006-05-04 for methods and devices for obstructing and aspirating lung tissue segments.
This patent application is currently assigned to PULMONx. Invention is credited to Wally S. Buch, Robert Kotmel, Michael P. Reilly, Peter P. Soltesz, Tony Wondka.
Application Number | 20060095002 11/271211 |
Document ID | / |
Family ID | 24808737 |
Filed Date | 2006-05-04 |
United States Patent
Application |
20060095002 |
Kind Code |
A1 |
Soltesz; Peter P. ; et
al. |
May 4, 2006 |
Methods and devices for obstructing and aspirating lung tissue
segments
Abstract
The present invention provides improved methods, systems,
devices and kits for performing lung volume reduction in patients
suffering from chronic obstructive pulmonary disease or other
conditions where isolation of a lung segment or reduction of lung
volume is desired. The methods are minimally invasive with
instruments being introduced through the mouth (endotracheally) and
rely on isolating the target lung tissue segment from other regions
of the lung. Isolation is achieved by deploying an obstructive
device in a lung passageway leading to the target lung tissue
segment. Once the obstructive device is anchored in place, the
segment can be aspirated through the device. This may be achieved
by a number of methods, including coupling an aspiration catheter
to an inlet port on the obstruction device and aspirating through
the port. Or, providing the port with a valve which allows outflow
of gas from the isolated lung tissue segment during expiration of
the respiratory cycle but prevents inflow of air during
inspiration. In addition, a number of other methods may be used.
The obstructive device may remain as an implant, to maintain
isolation and optionally allow subsequent aspiration, or the device
may be removed at any time.
Inventors: |
Soltesz; Peter P.;
(Henderson, NV) ; Kotmel; Robert; (Burlingame,
CA) ; Wondka; Tony; (Thousand Oaks, CA) ;
Reilly; Michael P.; (Southlake, TX) ; Buch; Wally
S.; (Atherton, CA) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP
TWO EMBARCADERO CENTER
EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
PULMONx
Palo Alto
CA
|
Family ID: |
24808737 |
Appl. No.: |
11/271211 |
Filed: |
November 9, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10382131 |
Mar 4, 2003 |
6997918 |
|
|
11271211 |
Nov 9, 2005 |
|
|
|
09699302 |
Oct 27, 2000 |
6527761 |
|
|
10382131 |
Mar 4, 2003 |
|
|
|
Current U.S.
Class: |
604/39 |
Current CPC
Class: |
A61B 17/12104 20130101;
A61B 17/1219 20130101; A61B 2017/1205 20130101; A61B 17/12022
20130101; A61B 17/12136 20130101; A61B 2017/22068 20130101; A61B
17/12172 20130101; A61B 17/12159 20130101; A61B 2017/22067
20130101 |
Class at
Publication: |
604/039 |
International
Class: |
A61M 3/02 20060101
A61M003/02 |
Claims
1. A method for lung volume reduction, said method comprising:
deploying an obstructive device in a lung passageway to a lung
tissue segment; and aspirating the segment to at least partially
collapse the lung segment, wherein the obstructive device is
removable.
2. A method as in claim 1, wherein the device is removable by
collapsing the structure.
3. A method as in claim 1, further comprising collapsing the
obstructive device and removing the device.
4. A method as in claim 1, wherein the device biodegrades in the
lung over time.
5. A method as in claim 1, wherein the obstructive device is
coated.
6. A method as in claim 5, wherein the obstructive device is coated
with an antibiotic.
7. A method as in claim 1, wherein the device is impregnated with
an adhesive.
8. A method as in claim 1, wherein aspirating comprises coupling an
aspiration catheter to the obstructive device and aspirating gas
through the catheter from the segment.
9. A method as in claim 8, wherein the obstructive device comprises
an inlet port, the aspiration catheter comprises an access tube and
coupling comprises passing an access tube through the inlet
port.
10. A method for lung volume reduction, said method comprising:
deploying an obstructive device in a lung passageway to a lung
tissue segment; and aspirating the segment to at least partially
collapse the lung segment, wherein the obstructive device is
biodegradable when left in place in the lung.
11. A method as in claim 10, wherein the device is removable.
12. A method as in claim 10, wherein the device is coated.
13. A method as in claim 12, wherein the device is coated with an
antibiotic.
14. A method as in claim 10, wherein the device is impregnated with
an adhesive.
15. A method as in claim 10, wherein aspirating comprises coupling
an aspiration catheter to the obstructive device and aspirating gas
through the catheter from the segment.
16. A method as in claim 15, wherein the obstructive device
comprises an inlet port, the aspiration catheter comprises an
access tube and coupling comprises passing an access tube through
the inlet port.
17. A method for lung volume reduction, said method comprising:
deploying an obstructive device in a lung passageway to a lung
tissue segment; and aspirating the segment to at least partially
collapse the lung segment, wherein the obstructive device is coated
and/or impregnated with a material.
18. A method as in claim 17, wherein the obstructive device is
coated with an antibiotic.
19. A method as in claim 17, wherein the obstructive device is
impregnated with an adhesive.
20. A method as in claim 17, wherein the device is removable by
collapsing.
21. A method as in claim 17, wherein the device is
biodegradable.
22. A method as in claim 17, wherein aspirating comprises coupling
an aspiration catheter to the obstructive device and aspirating gas
through the catheter from the segment.
23. A method as in claim 22, wherein the obstructive device
comprises an inlet port, the aspiration catheter comprises an
access tube and coupling comprises passing an access tube through
the inlet port.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 10/382,131 (Attorney Docket No.
017534-001210US), filed Mar. 4, 2003, which was a continuation of
U.S. patent application Ser. No. 09/699,302 (Attorney Docket No.
017534-001200), filed Oct. 27, 2000, which is related to co-pending
U.S. patent application Ser. No. 09/699,313 (Attorney Docket No.
017534-001300), also filed Oct. 27, 2000, the full disclosures of
which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to medical methods,
systems, and kits. More particularly, the present invention relates
to methods and apparatus for effecting lung volume reduction by
aspirating isolated segments of lung tissue.
[0004] Chronic obstructive pulmonary disease is a significant
medical problem affecting 16 million people or about 6% of the U.S.
population. Specific diseases in this group include chronic
bronchitis, asthmatic bronchitis, and emphysema. While a number of
therapeutic interventions are used and have been proposed, none are
completely effective, and chronic obstructive pulmonary disease
remains the fourth most common cause of death in the United States.
Thus, improved and alternative treatments and therapies would be of
significant benefit.
[0005] Of particular interest to the present invention, lung
function in patients suffering from some forms of chronic
obstructive pulmonary disease can be improved by reducing the
effective lung volume, typically by resecting diseased portions of
the lung. Resection of diseased portions of the lungs both promotes
expansion of the non-diseased regions of the lung and decreases the
portion of inhaled air which goes into the lungs but is unable to
transfer oxygen to the blood. Lung reduction is conventionally
performed in open chest or thoracoscopic procedures where the lung
is resected, typically using stapling devices having integral
cutting blades.
[0006] While effective in many cases, conventional lung reduction
surgery is significantly traumatic to the patient, even when
thoracoscopic procedures are employed. Such procedures often result
in the unintentional removal of healthy lung tissue, and frequently
leave perforations or other discontinuities in the lung which
result in air leakage from the remaining lung. Even technically
successful procedures can cause respiratory failure, pneumonia, and
death. In addition, many older or compromised patients are not able
to be candidates for these procedures. For these reasons, it would
be desirable to provide improved methods, systems, and kits for
performing lung volume reduction which overcome at least some of
the shortcomings noted above.
[0007] 2. Description of the Background Art
[0008] WO 99/01076 and corresponding U.S. Pat. No. 5,957,919
describes devices and methods for reducing the size of lung tissue
by applying heat energy to shrink collagen in the tissue. In one
embodiment, air may be removed from a bleb in the lung to reduce
its size. Air passages to the bleb may then be sealed, e.g., by
heating, to fix the size of the bleb. WO 98/48706 describes a
plug-like device for placement in a lung air passage to isolate a
region of lung tissue, where air is not removed from the tissue
prior to plugging. WO 98/49191 describes the use of surfactants in
lung lavage for treating respiratory distress syndrome. U.S. Pat.
No. 5,925,060 may also be of interest.
[0009] Patents and applications relating to lung access, diagnosis,
and treatment include U.S. Pat. Nos. 5,957,949; 5,840,064;
5,830,222; 5,752,921; 5,707,352; 5,682,880; 5,660,175; 5,653,231;
5,645,519; 5,642,730; 5,598,840; 5,499,625; 5,477,851; 5,361,753;
5,331,947; 5,309,903; 5,285,778; 5,146,916; 5,143,062; 5,056,529;
4,976,710; 4,955,375; 4,961,738; 4,958,932; 4,949,716; 4,896,941;
4,862,874; 4,850,371; 4,846,153; 4,819,664; 4,784,133; 4,742,819;
4,716,896; 4,567,882; 4,453,545; 4,468,216; 4,327,721; 4,327,720;
4,041,936; 3,913,568 3,866,599; 3,776,222; 3,677,262; 3,669,098;
3,542,026; 3,498,286; 3,322,126; WO 95/33506, and WO 92/10971.
[0010] Lung volume reduction surgery is described in many
publications, including Becker et al. (1998) Am. J. Respir. Crit.
Care Med. 157:1593-1599; Criner et al. (1998) Am. J. Respir. Crit.
Care Med. 157:1578-1585; Kotloffet al. (1998) Chest 113:890-895;
and Ojo et al. (1997) Chest 112:1494-1500.
[0011] The use of mucolytic agents for clearing lung obstructions
is described in Sclafani (1999) AARC Times, January, 69-97. Use of
a balloon-cuffed bronchofiberscope to reinflate a lung segment
suffering from refractory atelectasis is described in Harada et al.
(1983) Chest 84:725-728.
SUMMARY OF THE INVENTION
[0012] The present invention provides improved methods, systems,
devices and kits for performing lung volume reduction in patients
suffering from chronic obstructive pulmonary disease or other
conditions where isolation of a lung segment or reduction of lung
volume is desired. The present invention is likewise suitable for
the treatment of bronchopleural fistula. The methods are minimally
invasive with instruments being introduced through the mouth
(endotracheally) and rely on isolating the target lung tissue
segment from other regions of the lung. Isolation is achieved by
deploying an obstructive device in a lung passageway leading to the
target lung tissue segment. Once the obstructive device is anchored
in place, the segment can be aspirated through the device. This may
be achieved by a number of methods, including coupling an
aspiration catheter to an inlet port on the obstruction device and
aspirating through the port. Or, providing the port with a valve
which allows outflow of gas from the isolated lung tissue segment
during expiration of the respiratory cycle but prevents inflow of
air during inspiration. In addition, a number of other methods may
be used. The obstructive device may remain as an implant, to
maintain isolation and optionally allow subsequent aspiration, or
the device may be removed at any time. Likewise, the device may
biodegrade over a period of time.
[0013] The obstruction device may take a variety of forms to allow
delivery, deployment and anchoring in a lung passageway. Delivery
is commonly performed with the use of a minimally invasive device,
such as a flexible bronchoscope or an access catheter. The flexible
bronchoscope may be utilized with a sheath having an inflatable
cuff disposed near its distal end, a full description of which is
provided in co-pending application [Attorney Docket No.
017534-001300], assigned to the assignee of the present invention
and incorporated by reference for all purposes. When using such a
sheath, the scope is introduced into a lumen in the sheath to form
an assembly which is then introduced to the lung passageway. The
cuff may then be inflated to occlude the passageway. Similarly, an
access catheter may be used which may be steerable or articulating,
may include an inflatable balloon cuff near its distal end and may
include a number of lumens for balloon inflation, tracking over a
guidewire, and optical imaging, to name a few. The obstruction
device is typically housed within a lumen of the access catheter,
bronchoscope, sheath or suitable device, mounted near the distal
tip of the catheter or carried by any method to the desired lung
passageway leading to the target lung tissue segment. Therefore,
the obstruction device must be sized appropriately for such
delivery and is typically designed to expand upon deployment to
anchor within the lung passageway. Hereinafter the present
invention is depicted in relation to use with an access catheter,
however it may be appreciated that any suitable device may be
used.
[0014] In a first aspect of the present invention, the obstruction
device comprises a structural support which expands and thereby
anchors the device in the lung passageway. Such supports may
comprise a number of configurations for a variety of expansion
techniques. For example, the structural supports may allow the
obstruction device to coil, roll, bend, straighten or fold in a
cone, rod, cylinder or other shape for delivery. Then, once
positioned in a desired location, the obstruction device may be
released and expanded to anchor the device in the passageway. Such
expansion may be unaided, such as in the release of a compressed
structure to a pre-formed expanded position. Or, such expansion may
be aided, such as with the use of an inflatable balloon or cuff. In
some cases, a balloon or inflatable member may be incorporated into
the obstruction device and may remain inflated to occlude the
passageway. This may be provided in combination with structural
supports or an inflatable balloon or similar device may be used
without such support.
[0015] The structural supports may be comprised of any type of
wire, particularly superelastic, shape-memory or spring tempered
wire, or any type of polymer or a suitable material. The balloon or
inflatable member may be comprised of any flexible, polymeric
material suitable for such a purpose. The member may be inflated
with gas or liquid as desired, or it may be inflated with an
expanding foam or similar material. Likewise, it may be inflated or
injected with an adhesive. Such an adhesive may expand the member
and/or rigidify the member to reduce the likelihood of collapse.
Further, the adhesive may additionally serve to bond the device to
the walls of the lung passageway to increase anchorage. In
addition, the device may be impregnated or coated with an
antibiotic agent, such as silver nitrate, or similar agent for
delivery of the agent to the lung passageway. Such delivery may
occur by any applicable means.
[0016] When structural supports are present, such supports may
comprise a variety of designs. In a first embodiment, the
structural supports comprise radial segments which expand to fill
the passageway and longitudinal segments which rest against the
walls of the passageway to help anchor the device. In a second
embodiment, the structural supports comprise a mesh which expands
to fill the passageway. In a third embodiment, the structural
supports comprise a helically or spirally wound wire which also
expands to contact the walls of the passageway and anchor the
device. In each of these embodiments, the structural support may be
connected with or encapsulated in a sack comprised of a thin
polymeric film, open or closed cell foam or other suitable material
to provide a seal against walls of the lung passageway and obstruct
airflow through the device. The sack material may also be infused
with an adhesive, sealant or other material to improve obstruction
of the airway and possibly improve adhesion to the airway
walls.
[0017] In a second aspect of the present invention, the obstruction
device may further comprise ports for aspiration through the
device. This may allow access to the collapsed lung segment at a
later time, for example, in the case of an infection. Typically,
the obstruction device will have an inlet port located near the
proximal end of the device, away from the isolated lung tissue
segment. Such a port is thus accessible by minimally invasive
devices, such as an aspiration catheter, which may be advanced
through the bronchial passageways. Optionally, an outlet port may
be located near the distal end of the obstruction device. The ports
may comprise a variety of designs for a number of purposes.
[0018] In a first embodiment, the port comprises a self-sealing
septum. Such a septum may comprise a solid membrane or a pre-cut
membrane. Aspiration through the port may be achieved with the use
of an aspiration catheter having an access tube or penetrating
element at its distal end. Such a catheter may be advanced to the
site of the obstruction device itself or with the use of an access
catheter. The septum may be penetrated, either pierced through a
solid membrane or passed through the cuts of a pre-cut membrane, by
the access tube. Depending on the design of the obstruction device,
the inlet port and optionally the outlet port may be penetrated in
this fashion. Aspiration may be achieved through the access tube
and aspiration catheter to withdraw gases and/or liquids from the
isolated lung tissue segment and passageway. Optionally, prior to
aspiration, a 100% oxygen, Helium-Oxygen mixture or low molecular
weight gas washout of the lung segment may be performed by
introducing such gas through the access tube, such as by a high
frequency jet ventilation process. In this case, aspiration would
remove both the introduced gas and any remaining gas. Similarly,
liquid perfluorocarbon or certain drugs, such as antibiotics,
retinoic acid and hyaluronic acid, may be introduced prior to
aspiration. In most cases, aspiration will at least partially
collapse the lung segment. Upon removal of the aspiration catheter
from the port, the septum may self-seal or it may be further sealed
with a sealant or other sealing means for later access or permanent
closure.
[0019] When the self-sealing septum comprises a pre-cut membrane,
aspiration through the port may alternatively be achieved by
coupling an aspiration catheter to the obstructive device. Coupling
may comprise engaging the aspiration catheter to the port or
sliding a coupling member or the aspiration catheter over the port
to form a seal. In either case, suction through the aspiration
catheter may allow gases and/or liquids to pass through the cuts in
the membrane to be withdrawn from the isolated lung tissue segment
and passageway. Again, this will at least partially collapse the
lung segment. Likewise, upon removal of the aspiration catheter
from the port, the septum may self-seal or it may be further sealed
with a sealant or other sealing means for later access or permanent
closure.
[0020] In a second embodiment, the port comprises a unidirectional
valve. Such a valve may comprise a port covered by a flexible layer
which is attached to the port by at least one point of connection.
Movement of the layer away from the port opens the valve and
movement against the port closes the valve. Wherein the flexible
layer is solid, movement of the layer away from the port allows gas
to flow between the points of connection and around the edges of
the flexible layer. Alternatively, the flexible layer may have
holes therethrough. In this case, the port may also comprise a
partition having holes which are not aligned with the holes in the
flexible layer. Movement of the layer away from the port allows gas
to flow through the holes in the partition and out through the
holes in the flexible layer. When the layer moves against the
partition, the holes will be covered closing the valve. Other valve
designs include a spring-loaded ball valve or a biased pre-loaded
diaphragm valve.
[0021] Aspiration through a unidirectional valve may be achieved by
a number of methods. Again, the port may be accessed by advancing
an aspiration catheter or similar device through the bronchial
passageways to the site of the obstruction device. This may
optionally be achieved with the use of an access catheter. The
aspiration catheter may be placed near the valve or engaged to the
valve, wherein suction or vacuum applied through the catheter opens
the valve. If the aspiration catheter is not engaged to the valve,
adequate suction to open the valve may be achieved by occluding the
passageway proximal to the point of suction which is typically the
distal end of the aspiration catheter. Such occlusion may be
achieved by inflating a balloon or occlusion device mounted on the
distal end of the aspiration catheter or mounted on an access
catheter. In either case, the vacuum may draw the flexible layer
away from the port, allowing gases and/or liquids to flow out from
the isolated lung segment, through the valve and into the
aspiration catheter. Alternatively, aspiration through a
unidirectional valve may be achieved naturally during respiration.
Pressure changes may open the valve during expiration as gases flow
out from the isolated lung segment. Reverse pressure changes,
during inspiration, may close the valve preventing gases from
flowing into the isolated segment. This may reduce the amount of
gas trapped in the terminal segment over time and thus at least
partially collapse the lung segment. Similarly, aspiration through
the unidirectional valve may be achieved by external mechanical
pressure on the lung to force out of the lung segment and through
the valve. Again, reverse pressure changes upon recoil of the lung
would close the valve preventing gases from flowing into the
isolated segment.
[0022] In a third aspect of the present invention, the obstruction
device may comprise a blockage device which is deployed in a lung
passageway to close the airway. Such a blockage device may be of
similar design as previously described obstruction devices as it
may be similarly delivered, deployed and anchored within a lung
passageway. Thus, embodiments of the blockage device typically
comprise expandable support structures. For example, in one
embodiment the support structure comprises a coil. And, in a second
embodiment, the support structure comprises a mesh. Again, the
support structures may be connected to or encased in a polymer film
or sack to provide a seal against the walls of the lung passageway
and obstruct airflow through the device. Typically the blockage
device will be placed in the passageway after the terminal lung
segment has been aspirated by other methods. This will seal off the
lung segment and maintain lung volume reduction. Alternatively, the
blockage device may be placed in the passageway before the terminal
lung segment has been aspirated. In this case, air trapped in the
lung segment may be absorbed over time and would eventually
collapse, a process known as absorption atelectasis. This process
may be enhanced by insufflating the lung segment with 100% oxygen,
a Helium-Oxygen mixture or low molecular weight gas prior to
placing the blockage device. Such enhancement may promote complete
collapse of the lung segment. In any case, the blockage device may
optionally be later removed if it is so desired.
[0023] Methods of the present invention include the utilization of
an obstruction device to achieve lung volume reduction. As
described above, methods include delivery, deployment and anchoring
of an obstruction device in a lung passageway leading to a target
lung tissue segment. At least partial collapse of the terminal lung
tissue segment may be achieved by aspirating the segment through
the obstruction device deployed in the passageway. Aspiration may
be accomplished with the use of an aspiration catheter or similar
device through a port on the obstruction device. Also described
above, when the port comprises a unidirectional valve, aspiration
and eventual lung volume reduction may be accomplished by the
opening and closing of the valve in response the respiratory cycle.
In addition, methods of the present invention include deployment of
a blockage device in a lung passageway leading to a terminal lung
tissue segment, as previously described.
[0024] Systems of the present invention may include any of the
components described in relation to the present invention. A
particular embodiment of a system of the present invention
comprises an access catheter and an obstruction device, as
described above, wherein the obstruction device is introduceable by
the access catheter. For example, the obstruction device may be
houseable within a lumen of the access catheter for deployment out
the distal end of the catheter, or the obstruction device may be
mountable on the access catheter near its distal end. In either
case, the obstruction device may be deployed and anchored within a
lung passageway.
[0025] The methods and apparatuses of the present invention may be
provided in one or more kits for such use. The kits may comprise an
obstruction device deployable within a lung passageway and
instructions for use. Optionally, such kits may further include any
of the other system components described in relation to the present
invention and any other materials or items relevant to the present
invention.
[0026] Other objects and advantages of the present invention will
become apparent from the detailed description to follow, together
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a perspective illustration of an access catheter
useful in the methods, systems, and kits of the present
invention.
[0028] FIG. 2 is a cross-sectional view taken along line 2 to a
FIG. 1.
[0029] FIGS. 3A-3F illustrate alternative cross-sectional views of
the access catheter of FIG. 1.
[0030] FIGS. 4A-4C illustrate a steerable imaging guidewire which
may be used to facilitate positioning of the access catheter used
in the methods of the present invention.
[0031] FIG. 5A illustrates use of the access catheter of FIG. 1 for
accessing a target lung tissue segment according the to the methods
of the present invention.
[0032] FIG. 5B illustrates use of a visualizing tracheal tube with
the access catheter of FIG. 1 for accessing a target tissue segment
according the to the methods of the present invention.
[0033] FIG. 6 illustrates a method of deployment or delivery of an
obstructive device.
[0034] FIGS. 7A-7B are perspective views of embodiments of
obstructive devices having, among other features, radial and
longitudinal structural supports.
[0035] FIG. 8 is a perspective view of an embodiment of an
obstructive device in a rolled configuration prior to release in a
lung passageway.
[0036] FIG. 9 is a perspective view of an embodiment of a rolled,
cylindrical shaped obstructive device in an expanded state within a
flexible sack.
[0037] FIG. 10 illustrates an embodiment of a double conical shaped
obstructive device.
[0038] FIG. 11 is a perspective view of an embodiment of an
obstructive device having, among other features, a mesh structural
support encased by a polymer film.
[0039] FIG. 12 is a perspective view of an embodiment of an
obstructive device having, among other features, a spiral
structural support.
[0040] FIG. 13 is a perspective view of an embodiment of an
obstructive device having a cone shape with an inlet port at the
apex of the cone.
[0041] FIGS. 14A-14C illustrate embodiments of self-sealing septums
of the present invention.
[0042] FIG. 15 illustrates a method of aspirating through an
obstructive device by inserting an access tube through a septum of
an inlet port.
[0043] FIG. 16 illustrates a method of aspirating through an
obstructive device by contacting an aspiration catheter to an inlet
port.
[0044] FIG. 17 illustrates a method of aspirating through an
obstructive device by sliding the distal end of an aspiration
catheter over an inlet port.
[0045] FIGS. 18A-18C illustrate a method of deploying, anchoring
and aspirating through an obstruction device while such a device is
connected to an aspiration catheter.
[0046] FIG. 19A is a front view of an embodiment of a
unidirectional valve of the present invention. FIGS. 19B-19C are
perspective views of the unidirectional valve of FIG. 19A in
various stages of operation.
[0047] FIGS. 20-21 illustrate positioning of embodiments of
unidirectional valves of the present invention in a lung
passageway.
[0048] FIGS. 22A-22B are front views of an embodiment of a
unidirectional valve of the present invention.
[0049] FIGS. 23A-23B are perspective views of the unidirectional
valve of FIGS. 21A-21B in various stages of operation.
[0050] FIG. 24 illustrates a method of deployment or delivery of a
blockage device.
[0051] FIG. 25 illustrates an embodiment of a blockage device
comprising a coil encased in a polymer film.
[0052] FIG. 26 illustrates an embodiment of a blockage device
comprising a mesh connected to a polymer film.
[0053] FIG. 27 illustrates an embodiment of a blockage device
comprising a barb-shaped structure.
[0054] FIG. 28 illustrates an embodiment of a blockage device
having a cylindrical-type balloon with textured friction bands.
[0055] FIG. 29 depicts an embodiment of a blockage device
comprising a multi-layer balloon which has an adhesive material
between an outer layer and an inner layer of the balloon.
[0056] FIG. 30 illustrates an embodiment of a blockage device which
is similar to that of FIG. 29, including openings in the outer
layer through which adhesive may seep.
[0057] FIG. 31 illustrates a kit constructed in accordance with the
principles of the present invention.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0058] Lung volume reduction is performed by collapsing a target
lung tissue segment, usually within lobar or sub-lobular regions of
the lung which receive air through a single lung passage, i.e.,
segment of the branching bronchus which deliver to and receive air
from the alveolar regions of the lung. Such isolated lung tissue
segments are first isolated and then collapsed by aspiration of the
air (or other gases or liquids which may be present) from the
target lung tissue segment. Lung tissue has a very high percentage
of void volume, so removal of internal gases can reduce the lung
tissue to a small percentage of the volume which it has when fully
inflated, i.e. inflated at normal inspiratory pressures. The
exemplary and preferred percentages for the volume reduction are
set forth above.
[0059] The methods of the present invention will generally rely on
accessing the target lung tissue segment using an access catheter
adapted to be introduced endotracheally into the bronchus of the
lung. An exemplary access catheter 10 is illustrated in FIGS. 1 and
2 and comprises a catheter body 12 having a distal end 14, a
proximal end 16, and at least one lumen therethrough. Optionally,
the catheter 10 further comprises an inflatable occlusion balloon
18 near its distal end. In this case, the catheter will have at
least two lumens, a central lumen 20 and a balloon inflation lumen
22. As shown in FIG. 2, the balloon inflation lumen 22 may be an
annular lumen defined by inner body member 24 and outer body member
26 which is coaxially disposed about the inner body member. The
lumen 22 opens to port 30 on a proximal hub 32 and provides for
inflation of balloon 18. The central lumen 20 opens to port 36 on
hub 32 and provides for multiple functions, including optional
introduction over a guidewire, aspiration, introduction of
secondary catheters, and the like.
[0060] The dimensions and materials of access catheter 10 are
selected to permit endotracheal introduction and intraluminal
advancement through the lung bronchus or passageway, optionally
over a guidewire and/or through a primary tracheal tube structure
(as illustrated in FIG. 4B below). Suitable materials include low
and high density polyethylenes, polyamides, nylons, PTFE, PEEK, and
the like, particularly for the inner tubular member 24. The outer
member, including the occlusion balloon, can be made from
elastomeric materials, such as polyurethane, low density
polyethylene, polyvinylchloride, silicone rubber, latex, and the
like. Optionally, portions of the outer tubular member 26 proximal
to the inflatable balloon can be made thicker and/or reinforced so
that they do not dilate upon pressurization of the balloon.
Exemplary dimensions for the access catheter 10 are set forth in
the table below. TABLE-US-00001 ACCESS CATHETER DIMENSIONS
Exemplary Preferred Inner Outer Inner Outer Tubular Tubular Tubular
Tubular Member Member Member Member Outer Diameter (mm) 0.4-4
0.6-4.5 1-1.5 2-4 Wall Thickness (mm) 0.05-0.25 0.5-0.25 0.1-0.2
0.15-0.25 Length (cm) 50-150 same 50-80 same Balloon Length (mm)
5-50 10-20 Balloon Diameter (mm) 2-20 6-15 (inflated)
[0061] The access catheter 10 may be modified in a number of ways,
some of which are illustrated in FIGS. 3A-3F. For example, instead
of an inner and outer coaxial tube construction, the catheter can
be a single extrusion having a catheter body 30 with a circular
main lumen 32 and a crescent-shaped inflation lumen 34, as
illustrated in FIG. 3A. Alternatively, catheter body 40 may be
formed as a single extrusion having three lumens, i.e., a primary
lumen 42 for receiving a guidewire, applying aspiration, and/or
delivering secondary catheters. A second lumen 44 can be provided
for inflating the occlusion balloon, and a third lumen 46 can be
provided as an alternative guidewire or aspiration lumen. Catheter
body 50 comprising a main tubular body 52 having an outer layer 54
fused thereover to define a lumen 56 suitable for balloon inflation
as shown in FIG. 3C. A primary lumen 58 is formed within the main
tubular member 52. As a slight alternative, catheter body 60 can be
formed from a primary tubular member 62, and a secondary tubular
member 64, where the tubular members are held together by an outer
member 66, such as a layer which is applied by heat shrinking. The
primary tubular member 62 provides the main lumen 68 while
secondary tube 64 provides a secondary lumen 70. The secondary
lumen 70 will typically be used for balloon inflation, while the
primary lumen 68 can be used for all other functions of the access
catheter.
[0062] Optionally, the access catheter in the present invention can
be provided with optical imaging capability. As shown in FIG. 3E,
catheter body 80 can be formed to include four lumens, typically by
conventional extrusion processes. Lumen 82 is suitable for passage
over a guidewire. Lumens 84 and 86 both contain light fibers 88 for
illumination. Lumen 90 carries an optical wave guide or image fiber
92. Lumen 82 can be used for irrigation and aspiration, typically
after the guidewire is withdrawn. Balloon inflation can be effected
through the space remaining and lumens 84 and 86 surrounding the
light fibers 88. A second catheter body 100 is formed as a coaxial
arrangement of a number separate tubes. Outer tube 102 contains a
separate guidewire tube 104 defining lumen 106 which permits
introduction over a guidewire as well as perfusion and aspiration
after the guidewire is removed. Second inner tubular member 110
will carry an optical image fiber 112 and a plurality of light
fibers 112 are passed within the remaining space 114 within the
outer tubular member. In both catheter constructions 80 and 100,
forward imaging can be effected by illuminating through the light
fibers and detecting an image through a lens at the distal end of
the catheter. The image can be displayed on conventional
cathode-ray or other types of imaging screens. In particular, as
described below, forward imaging permits a user to selectively
place the guidewire for advancing the catheters through a desired
route through the branching bronchus.
[0063] Usually, positioning of a guidewire through the branching
bronchus will be manipulated while viewing through the imaging
components of the access catheter. In this way, the access catheter
can be "inched" along by alternately advancing the guidewire and
the access catheter. As an alternative to providing the access
catheter with imaging, positioning could be done solely by
fluoroscopy. As a further alternative, a steerable, imaging
guidewire 300 (FIGS. 4A-4C) could be used. The guidewire 300
includes a deflectable tip 302 which can be deflected in a single
plane using push/pull ribbon 304. Usually, the tip will comprise a
spring 306 to facilitate deflection. In addition to steerability,
the guidewire 300 will include an optical imaging wave guide 310
and illuminating optical fibers 312, as best seen in
cross-sectional view of FIG. 4C. Thus, the guidewire 300 can be
steered through the branching bronchus to reach the target tissue
segment using its own in situ imaging capability. Once the
guidewire 300 is in place, an access catheter can be introduced to
the target lung tissue segment as well. Since the guidewire has
imaging capability, the access catheter need not incorporate such
imaging. This can be an advantage since it permits the access lumen
to be made larger since the catheter need not carry any optical
wave guides.
[0064] Referring now to FIG. 5A, a catheter 10 can be advanced to a
lung tissue segment, specifically a diseased region DR, within a
lung L through a patient's trachea T. Advancement through the
trachea T is relatively simple and will optionally employ an
endotracheal tube and/or a guidewire to select the advancement
route through the branching bronchus. The endotracheal tube may
have a thin-walled design wherein the inner diameter is larger than
in standard endotracheal tubes. Standard endotracheal tubes have a
7.0 mm ID with a 10 mm OD. The thin-walled design would have a 9.0
mm ID with a 10 mm OD; the larger ID allows the insertion of a
larger instrument while providing adequate ventilation. Steering
can be effected under real time imaging using the imaging access
catheters illustrated in FIGS. 3E and 3F. Optionally, the access
catheter 10 may be introduced through a visualizing tracheal tube,
such as that described in U.S. Pat. No. 5,285,778, licensed to the
assignee of the present application. As shown in FIG. 5B, the
visualizing endotracheal tube 120 includes an occlusion cuff 122
which may be inflated within the trachea just above the branch of
the left bronchus and right bronchus LB and RB, respectively. The
visualizing endotracheal tube 120 includes a forward-viewing
optical system, typically including both illumination fibers and an
image fiber to permit direct viewing of the main branch between the
left bronchus LB and right bronchus RB. Thus, initial placement of
the access catheter 10 can be made under visualization of the
visualizing endotracheal tube 120 and optionally the access
catheter 10 itself. It may be appreciated that the access catheter
may be positioned with or without the use of a trachea tube or
similar device. When such a device is used, it may take a number of
forms and may be positioned in a number of locations. For example,
the trachea tube or device may be positioned as shown in FIG. 5A,
or it may be positioned to achieve "one lung ventilation" wherein
the side of the lung not involved in the corrective procedure will
be properly ventilated. Likewise, the access catheter may be
positioned under local anesthesia without intubation. In any case,
referring again in particular to FIG. 5A, the access catheter 10 is
advanced until its distal end 14 reaches a region in the bronchus
or lung passageway which leads directly into the diseased region
DR.
[0065] Once the distal end 14 of the access catheter 10 is
positioned in a desired location within the lung passageway, an
obstructive device may be deployed in the passageway. The method of
deployment or delivery of the obstructive device is dependent on a
number of factors, particularly the design of the obstructive
device itself. Typically, the obstructive device is housed within
the access catheter 10 or within a catheter that may be passed
through the access catheter 10. As depicted in FIG. 6, the
obstructive device 150 may be compressed or collapsed within an
interior lumen of the access catheter 10. The obstructive device
150 depicted is one of many designs which may be utilized. The
obstructive device 150 may then be pushed out of the distal end 14
of the catheter 10, in the direction of the arrow, into the lung
passageway 152. If the device 150 is self-expanding, for example by
tension or shape-memory, the device 150 will expand and anchor
itself in the passageway 152. If the device 150 is not
self-expanding, it may be expanded with the use of a balloon or
other mechanism provided by the access catheter 10, a catheter or
device delivered through the access catheter 10, or another device.
Similarly, the obstructive device 150 may be mounted or crimped
over the access catheter 10 (not shown) or a delivery catheter and
delivered to the desired location. A sheath may then be placed over
the device 150 during insertion. Deployment of the device 150 may
be achieved by withdrawing the sheath and allowing the device 150
to self-expand or expanding the device 150 with the use of a
balloon or other mechanism.
[0066] A variety of embodiments of obstructive devices 150 are
provided. To begin, a number of embodiments of the obstructive
device 150 are comprised of structural supports which expand to
anchor the device 150 in the passageway 152. Referring to FIG. 7A,
the supports 154 may be comprised of radial segments 160 and
longitudinal segments 162. The radial segments 160 allow the device
150 to expand to fill the passageway 152 and the longitudinal
segments 162 rest against the walls of the passageway 152 to help
anchor the device 150. The supports 154 may be individual, as shown
in FIG. 7A, or may be connected to one another, as shown in FIG.
7B, for example. In addition, the supports 154 may continue along a
proximal end 164 and distal end 166 of the device 150, as shown in
FIG. 7A, or the supports 154 may not be present at such ends 164,
166, as shown in FIG. 7B.
[0067] Referring to FIGS. 8-11, the supports 154 may be comprised
of a mesh 170 or similar interlocking structure. As shown in FIG.
8, the mesh 170 may be coiled or rolled into a cylindrical shape to
fit within an inner lumen of a delivery or access catheter or to be
mounted on the end of a such a delivery or access catheter. In
either case, the device 150 may be released within the lung
passageway 152 where the mesh 170 expands, uncoils and/or unrolls
to fill the passageway 152. Such release may allow self-expansion
or may involve the use of mechanical means to expand the mesh 170.
The expanded device 150 may fill the passageway 152 in a generally
cylindrical shape, as shown in FIG. 9, in single or double conical
shape, as shown in FIG. 10, or it may form a variety of other
shapes, an example of which is shown in FIG. 11.
[0068] Referring now to FIG. 12, the supports 154 may be a helix or
spiral 171 comprised of helically wound or spiral wound wire. The
spiral 171 may be compressed in a number of ways to load the spiral
171 within a lumen or on a distal end of a delivery catheter. For
example, the spiral 171 may be wound tightly, similar to a watch
spring, to reduce the cross-section of the spiral and provide
spring tension. Upon release of the spiral 171, the coils 173
expand to contact the walls of the passageway 152 and anchor the
device 150.
[0069] In any of the above embodiments, the supports 154 may be
connected to, encapsulated in, coated or impregnated with a
material to prevent flow of gases or liquids through the structural
supports 154, thereby providing an obstruction. In addition, the
material may include an antibiotic agent for release into the lung
passageway. Examples of obstructive materials include a thin
polymer film 156, such as webbing between the structural supports
154, which may be used to seal against the surface of the lung
passageway 152. Such a design is depicted in FIGS. 7A-7B, 10 and
12. Similarly, the structural supports 154 may be filled with an
adhesive or sealant which will adhere the structural support
members together and prevent flow or gasses or liquids through the
device 150. This is particularly useful in coiled or mesh designs
in where the structural support members are relatively close
together. Alternatively, as shown in FIG. 9 and FIG. 11, the
supports 154 may be encased in a sack 158 comprised of a thin
polymer, foam or other material. Expansion of the supports 154
within the sack 158 presses the sack 158 against the walls of the
passageway 152 forming a seal. In FIG. 9, the sack 158 has been
extended beyond the ends of the rolled support structure 154 for
illustration purposes to differentiate between the sack 158 and
support structure 154. However, typically, the support structure
154 will fill the sack 158. Again, the presence of the sack 158
prevents flow of gases or liquids through the supports 154, thereby
providing an obstruction. It may be appreciated that the structural
supports may comprise a variety of designs, creating devices 150 of
various lengths and shapes. Alternatively, the sack 158 may be
utilized without structural supports 154. The sack may expand to
fill the passageway by a variety of methods and may be held in
position by impregnation with an adhesive or other material. Such
impregnation may rigidify or support the sack to provide
obstruction of the lung passageway.
[0070] In addition and also shown in FIGS. 7A, 7B, 9, 11-13, a
number of embodiments of the obstructive device 150 include an
inlet port 172, located near the proximal end 164, and an outlet
port 174, located near the distal end 166. Such ports 172, 174 may
be of any size or shape but are typically round or oval and are
often located near the center of the passageway 512 lumen for ease
of accessibility. Some devices 150 may only include an inlet port
172 near the proximal end 164, as shown in FIG. 13. In this case,
the distal end 166 is expanded to contact the walls of the lung
passageway 152 and anchor the device 150. Thus, the obstruction
device 150 appears to have a cone shape with the inlet port 172 at
the apex of the cone. To ensure concentric placement of the
obstruction device 150, the device 150 should contact the walls of
the passageway 152 for a length of at least 1.0 to 1.5 times the
internal diameter of the passageway that the device 150
occupies.
[0071] The inlet port 172, outlet port 174 or both may comprise a
membrane or septum 176 covering the opening of the port. The septum
176 will typically be self-sealing. One type of self-sealing septum
176 comprises a solid membrane 178, illustrated in FIG. 14A. Other
types comprise pre-cut membranes in which the septum 176 includes
cuts 180 or slits, as shown in FIGS. 14B and 14C. Such cuts 180 may
allow ease of penetration through the septum 176 by an access tube
or penetrating element, as will be later described, while
preventing flow through the septum when the penetrating element is
removed.
[0072] After the obstruction device 150 is deployed and anchored
within a lung passageway 152 leading to a lung tissue segment, the
device 150 may be left as an implant to obstruct the passageway 152
from subsequent airflow. Airflow may include air and/or any other
gas or combination of gases, such as carbon dioxide. However,
immediately after placement or at any time thereafter, the above
described embodiments of the device 150 may be accessed to aspirate
the lung tissue segment through the obstructive device 150. This
will cause the segment to at least partially collapse as part of a
method for lung volume reduction. Aspirating through the
obstructive device 150 may be accomplished by a variety of methods.
For example, referring to FIG. 15, aspiration may be achieved by
first inserting a penetration element, needle or access tube 200
through the septum 176 of the inlet port 172. Positioning of the
access tube 200 for such insertion may be achieved by any method,
however, the access tube 200 is typically positioned by inserting
the access tube 200, or a catheter carrying the access tube 200,
through a lumen in the access catheter 10 until it passes out of
the distal end 14. Inflating the balloon 18 on the access catheter
10 may center the distal end 14 of the catheter in the lung
passageway 152. If the inlet port 172 is similarly centered, the
access tube 200 may be passed directly out of the catheter 10 and
through the septum 176 of the inlet port 172.
[0073] If the septum 176 is a solid membrane 178, the access tube
200 may be sharp enough to puncture or pierce the membrane 178. If
the septum 176 has cuts 180 or slits, the access tube 200 may be
pushed through the cuts 180. In either case, the membrane or septum
176 will seal around the access tube 200. If the obstruction device
150 also has an outlet port 174, the access tube 200 may optionally
be passed through both the inlet and outlet ports 172, 174. Once
the access tube 200 is inserted, gases and/or liquids may be
aspirated through the access tube 200 from the lung tissue segment
and associated lung passageways. Optionally, prior to aspiration, a
100% oxygen, Helium-Oxygen mixture or low molecular weight gas
washout of the lung segment may be performed by introducing such
gas through the access tube 200. In this case, aspiration would
removed both the introduced gas and any remaining gas. Similarly,
liquid perfluorocarbon or certain drugs, such as antibiotics, may
be introduced prior to aspiration. This may allow access to the
collapsed lung segment at a later time, for example, in the case of
an infection. In most cases, aspiration will at least partially
collapse the lung segment, as previously described. The access tube
200 may then be withdrawn. The septum 176 of the inlet port 172
and/or outlet port 174 will then automatically seal, either by
closing of the puncture site or by closure of the cuts. Optionally,
the ports may be additionally sealed with a sealant or by use of a
heat source or radiofrequency source.
[0074] Referring to FIGS. 16 and 17, aspiration through the
obstructive device 150 may be achieved by contacting the
obstructive device 150 with a suction tube or aspiration catheter
202 and aspirating gas or liquids through the device 150. As shown
in FIG. 16, the distal end 204 of the aspiration catheter 202 may
be held against the inlet port 172. Positioning of the aspiration
catheter 202 for such contact may be achieved by any method,
however the catheter 202 is typically positioned in a manner
similar to the access tube described above. By holding the
aspiration catheter 202 against the port 172, a seal may be created
and gases and/or liquids may be aspirated from the lung tissue
segment through the device 150. In this case, the inlet port 172
and the outlet port 174, if present, must not be covered by a solid
membrane 178. If cuts 180 are present, the gas or liquid may flow
through the port due to the pressure of the suction. As shown in
FIG. 17, the distal end 204 of the aspiration catheter 202 may be
slid over the inlet port 172 to form a seal. Again, gases and/or
liquids may then be aspirated through the device 150 in a similar
manner. The aspiration catheter 202 may then be withdrawn. The
septum 176 of the inlet port 172 and/or outlet port 174 will then
automatically seal, typically by closure of the cuts. Optionally,
the ports may be additionally sealed with a sealant or by use of a
heat source or radiofrequency source.
[0075] Referring to FIGS. 18A-18C, the obstruction device 150 may
be deployed, anchored and aspirated therethrough while connected to
an aspiration catheter 210. In this case, the access catheter 10 is
positioned within the lung passageway 152 at a desired location. If
the catheter 10 has an inflatable occlusion balloon 18 near its
distal end 14, the balloon 18 may be inflated to secure and center
the catheter 10 within the passageway 152; however, this step is
optional. As shown in FIG. 18A, an aspiration catheter 210 carrying
an obstruction device 150 is then introduced through a lumen in the
access catheter 10. As shown in FIG. 18B, the aspiration catheter
210 is advanced so that the obstruction device 150 emerges from the
distal end 14 of the access catheter 10 and deploys within the lung
passageway 152. Expansion and anchoring of the obstruction device
150 within the passageway 152 may be achieved by self-expansion or
by expansion with the aid of a balloon, for example. The lung
tissue segment isolated by the device 150 is then aspirated through
the device 150 and the attached aspiration catheter 210. Such
aspiration may remove air, gases, or liquids from the segment and
lung passageway 152 to at least partially collapse the lung
segment. As shown in FIG. 15C, the obstruction device 150 is then
detached from the aspiration catheter 210 and left behind in the
passageway 152. The proximal end 164 of the obstruction device 150
may comprise an inlet port 172 which would allow subsequent access
to the isolated lung tissue segment at a later time. Alternatively,
the proximal end 164 may comprise a sealed end, wherein the
obstruction device 150 may not be subsequently accessed and may
provide long-term isolation of the terminal lung tissue
segment.
[0076] It may be appreciated that the above described method may be
similarly achieved without the use of an aspiration catheter 210.
In this case, the obstruction device 150 may be carried directly by
the access catheter 10 and may be deployed while remaining attached
to the access catheter 10. Aspiration may be achieved through the
obstruction device 150 and the access catheter 10 to remove gases
from the isolated lung tissue segment and passageway 152. The
obstructive device 150 may then be detached from the access
catheter 10 and left behind in the passageway 152 for subsequent
access or simple occlusion.
[0077] At this point, all catheters and instruments may be
withdrawn from the patient and the obstruction device 150 may
remain in its anchored position, as described. The obstruction
device 150 will essentially occlude the lung passageway 152 and
prevent the inflow or outflow of air or gases to the isolated lung
tissue segment or diseased region DR. This may be effective in
maintaining the desired level of collapse of the lung tissue
segment to achieve lung volume reduction. However, at any point,
the lung tissue segment may be reaccessed and/or reaspirated by
repeating the steps described above. In addition, at any point, the
obstruction device 150 may be removed from the lung passageway 152,
either by collapse of the expandable structure or by other
means.
[0078] Additional embodiments of the obstructive device 150 are
comprised of a unidirectional valve. The valve may be operated upon
access or it may operate in response to respiration. For example,
when the valve is positioned in the lung passageway, the valve may
be accessed by engaging an aspiration catheter or a coupling member
to the valve. Aspiration through the aspiration catheter or
coupling member then opens the valve to remove gases and/or liquids
from the isolated lung segment. Alternatively, the valve may open
automatically in response to respiration. The valve may open during
expiration to allow outflow of gas from the lung segment and the
close during inspiration to prevent inflow of gas to the lung
segment. In either case, the unidirectional valves may take a
number of forms.
[0079] One embodiment of such a unidirectional valve is illustrated
in FIGS. 19A-19C. In this embodiment, the unidirectional valve 230,
front-view shown in FIG. 19A, is comprised of a port 232 and a
flexible layer 233 which is attached to the port 232 by at least
one point of connection 234. As shown, the flexible layer 233 may
be attached to the front surface of the port 232 at four
symmetrical points of connection 234. In preferred embodiments,
edges 236 of the layer 233 are positioned outside of the opening of
the port 232 (indicated by dashed lines). This provides a desired
seal when the valve is in the closed position.
[0080] Side-views shown in FIGS. 19B and 19C depict the valve 230
during different stages of the respiratory cycle. During
expiration, the valve 230 opens, as depicted in FIG. 19B. Here,
expiration of gases is illustrated by arrows. Gases exiting through
the lung passageway, within which the valve 230 is positioned,
apply force to the backside of the flexible layer 233 causing the
layer 233 to expand outwardly away from the surface of the port 232
as shown. This allows the gases to flow through the spaces between
the points of connection 234. During inspiration, the valve 230
closes, as depicted in FIG. 19C. Here, inspiration of air is
illustrated by an arrow. Air entering the lung passageway applies
force to the front side of the flexible layer 233 causing the layer
233 to seal against the surface of the port 232 as shown. This
prevents gases from flowing through the valve 230.
[0081] Unidirectional valves 230 may be positioned in the lung
passageway 152 by methods similar to those previously described for
other types of obstruction devices 150. As shown in FIG. 20, the
valve 230 may be positioned in the passageway 152 so that the
outside perimeter of the port 232 contacts the walls of the
passageway 152. In this way, the valve 230 is essentially the size
of the passageway lumen and provides the maximum area for potential
flow-through of gas. The valve 230 is depicted in its open state,
with gas flow traveling from an isolated lung tissue segment,
through the valve and out of the patient's airways. As shown in
FIG. 21, the valve 230 may alternatively be attached to or part of
structural supports 154 which expand radially to anchor the device
150 in the passageway 152. Such supports 154 are similar to those
previously described. Again, the valve 230 is depicted in its open
state. It may be appreciated that the valve 230 may be of any size
or shape and may substituted for any of the inlet and/or outlet
ports previously described.
[0082] Another embodiment of a unidirectional valve is illustrated
in FIGS. 22A-22B. In this embodiment, the valve 230 is comprised of
a port 232 and a flexible layer 233 as in the previous embodiment.
However, here the flexible layer 233 has a series of holes 250
through the layer. In addition, the valve 230 is comprised of a
partition 252 which also has holes 250. The holes 250 may be of any
size, shape or arrangement throughout the entire or a portion of
the layer 233 and partition 252. The partition 252 covers the port
232 and the layer 233 is positioned over the partition 252, as
illustrated in FIG. 22A and depicted by arrows, so that the holes
250 are substantially misaligned and therefore blocked. The
assembled valve, illustrated in FIG. 22B, does not have any through
holes 250 in the closed position. The holes 250 in the layer 233
are blocked by the underlying partition 252. Likewise, the holes
250 in the partition 252 are blocked by the overlying layer 233.
The layer 233 is attached to the partition 252 and/or port 232
along its perimeter; it may be a continuous attachment or may have
discrete points of connection with spaces therebetween.
[0083] Side-views shown in FIGS. 23B and 23C depict the valve 230
during different stages of the respiratory cycle. During
expiration, the valve 230 opens, as depicted in FIG. 23B. Here,
expiration of gases is illustrated by arrows. Gases exiting through
the lung passageway, within which the valve 230 is positioned, pass
through the holes 250 in the partition 252 and apply force to the
backside of the flexible layer 233. This causes the layer 233 to
expand outwardly away from the partition 252 as shown. This allows
the gases to flow through the holes 250 in the layer 233. During
inspiration, the valve 230 closes, as depicted in FIG. 23C. Here,
inspiration of air is illustrated by an arrow. Air entering the
lung passageway applies force to the front side of the flexible
layer 233 causing the layer 233 to seal against the surface of the
partition 252 as shown. This prevents gases from flowing through
the valve 230. This embodiment of a unidirectional valve 230 may be
positioned in a lung passageway 152 by methods similar to those
previously described for other types of obstruction devices 150,
particularly as shown in FIGS. 20 and 21.
[0084] Although the unidirectional valves described above are shown
as operating during different stages of the respiratory cycle, the
valves may additionally or alternatively be operated manually.
Valves positioned in a lung passageway, as depicted in FIGS. 20-21,
may be accessed by coupling an aspiration catheter to the valve.
Coupling may comprise engaging the aspiration catheter, a suitable
catheter or a coupling member to the valve. In some cases,
particularly when the valve 230 comprises a port 232 which is
smaller in diameter than the lumen of the lung passageway, as
depicted in FIG. 21, the distal end of the aspiration catheter or
coupling member may be slid over the port to form a seal. This was
previously depicted in FIG. 17 in relation to sealing of the
aspiration catheter 202 around an inlet port 172 of a non-valved
obstruction device. When a valve is present in this case,
aspiration through the aspiration catheter will open the valve and
draw gases and/or liquids from the lung tissue segment. With the
described unidirectional valves 230, the suction force of the
aspiration will draw the flexible layer 233 away from the port 232
or the partition 252 to open the valve.
[0085] Further embodiments of the obstructive device 150 are
comprised of a blockage device 280 having no ports through which
aspiration of the isolated lung tissue segment may be achieved.
After the blockage device 280 is deployed and anchored within a
lung passageway 152 leading to a lung tissue segment, the device
280 is to be left as an implant to obstruct the passageway 152 from
subsequent airflow. Although the previously described embodiments
of obstructive devices 150 having inlet and/or outlet ports 172,
174 may be utilized in a similar manner, the blockage device 280
may not be later accessed to aspirate the lung tissue segment
through the device. An example of such a blockage device 280 is
illustrated in FIGS. 24 and 25.
[0086] As with the previous obstructive devices, the blockage
device 280 may be housed within the access catheter 10 or within a
catheter that may be passed through the access catheter 10. As
depicted in FIG. 24, the obstructive device 150 may be compressed
or collapsed within an interior lumen of the access catheter 10.
The blockage device 280 depicted is one of many designs which may
be utilized. The blockage device 280 may then be pushed out of the
distal end 14 of the catheter 10, in the direction of the arrow,
into the lung passageway 152. The device 280 is to be
self-expanding by tension or shape-memory so that it will expand
and anchor itself in the passageway 152.
[0087] Referring to FIG. 25, one embodiment of the blockage device
280 comprises a coil 282. The coil 282 may be comprised of any type
of wire, particularly superelastic or shape-memory wire, polymer or
suitable material. The tension in the coil 282 allows the device
280 to expand to fill the passageway 152 and rest against the walls
of the passageway 152 to anchor the device 280. In addition, the
coil 282 may be connected to a thin polymer film 284, such as
webbing between the coils, to seal against the surface of the lung
passageway 152. Such a film 284 prevents flow of gases or liquids
through the coils, thereby providing an obstruction. Alternatively,
as depicted in FIG. 25, the coil 282 may be encased in a sack 286.
Expansion of the coil 282 within the sack 286 presses the sack 286
against the walls of the passageway 152 forming a seal. Again, this
prevents flow of gases or liquids, depicted by arrows, through the
coil 282, thereby providing an obstruction. Similarly, as depicted
in FIG. 26, another embodiment of the blockage device 280 comprises
a mesh 283. The mesh 283 may be comprised of any type of wire,
particularly superelastic or shape-memory wire, polymer or suitable
material. The tension in the mesh 283 allows the device 280 to
expand to fill the passageway 152 and rest against the walls of the
passageway 152 to anchor the device 280. In addition, the mesh 283
may be connected to a thin polymer film 284, such as webbing
between the lattice of the mesh, to seal against the surface of the
lung passageway 152. Such a film 284 prevents flow of gases or
liquids through the mesh, thereby providing an obstruction.
[0088] Referring now to FIG. 27, another embodiment of the blockage
device 280 comprises a barb-shaped structure 304 designed to be
wedged into a lung passageway 152 as shown. Such a structure 304
may be comprised of a solid material, an inflatable balloon
material, or any material suitable to provide a blockage function.
The structure 304 may be inflated before, during or after wedging
to provide sufficient anchoring in the lung passageway. Similarly,
the structure 304 may be impregnated or infused with an adhesive or
sealant before, during or after wedging to also improve anchoring
or resistance to flow of liquids or gasses through the passageway
152.
[0089] Referring to FIG. 28, another embodiment of the blockage
device 280 comprises an inflated balloon. Such a balloon may take a
number of forms. For example, the balloon may have take a variety
of shapes, such as round, cylindrical, conical, dogboned, or
multi-sectional, to name a few. Or, a series of distinct or
interconnected balloons may be utilized. Further, the surface of
the balloon may be enhanced by, for example, corrugation or
texturing to improve anchoring of the balloon within the lung
passageway. FIG. 28 illustrates a cylindrical-type balloon 300 with
textured friction bands 302 which contact the walls of the lung
passageway 152 when the balloon 300 is inflated as shown.
[0090] It may be appreciated that such balloons may be inflated
with an number of materials, including saline, gas, suitable
liquids, expanding foam, and adhesive, to name a few. Further, a
multi-layer balloon 310 may be utilized, as shown in FIG. 29, which
allows the injection of adhesive 312 or suitable material between
an outer layer 314 and an inner layer 316 of the balloon 310. Such
adhesive 312 may provide a hardened shell on the obstruction device
280 to improve its obstruction abilities. As shown, the balloon 310
may be inflated within the inner layer 316 with a foam 318 or other
material. Similarly, as shown in FIG. 30, the outer layer 314 of
the blockage device 280 may contain holes, pores, slits or openings
320 which allow the adhesive 312 to emerge through the outer layer
314 to the outside surface of the multi-layer balloon 310. When the
balloon 310 is inflated within a lung passageway 152, the outer
layer 314 of the balloon 310 will press against the walls of the
passageway 152 and the adhesive 312 will bond with the walls in
which it contacts. Such adhesion is designed to improve anchorage
and obstructive abilities of the blockage device 280.
[0091] It may also be appreciated that the above described blockage
devices may be impregnated, coated or otherwise deliver an
antibiotic agent, such as silver nitrate. Such incorporation may be
by any means appropriate for delivery of the agent to the lung
passageway. In particular, a multi-layer balloon may be provided
which allows the injection of an antibiotic agent between an outer
layer and an inner layer of the balloon 310. As previously
described and depicted in FIG. 30, the outer layer 314 of the
blockage device 280 may contain holes, pores, slits or openings 320
which allow the agent to emerge through the outer layer 314 to the
outside surface of the multi-layer balloon 310. Thus, the agent may
be delivered to the walls and/or the lung passageway.
[0092] It may further be appreciated that the blockage device 280
may comprise a variety of designs having various lengths and
shapes. In addition, many of the designs illustrated for use as a
blockage device 280 may also be adapted with an aspiration port for
use as described in relation to the previously illustrated
embodiments of obstruction devices 150. For example, such a port
172 having a septum 176 is shown in FIG. 30. If the port is not
accessed, the device simply serves as a blockage device 280. Thus,
in some cases, blockage devices 280 and obstructive devices 150 are
synonymous.
[0093] Referring now to FIG. 31, kits 400 according to the present
invention comprise at least an obstruction or blockage device 500
and instructions for use IFU. Optionally, the kits may further
include any of the other system components described above, such as
an access catheter 10, guidewire 402, access tube 200, aspiration
catheter 202 or other components. The instructions for use IFU will
set forth any of the methods as described above, and all kit
components will usually be packaged together in a pouch 450 or
other conventional medical device packaging. Usually, those kit
components which will be used in performing the procedure on the
patient will be sterilized and maintained sterilely within the kit.
Optionally, separate pouches, bags, trays, or other packaging may
be provided within a larger package, where the smaller packs may be
opened separately and separately maintain the components in a
sterile fashion.
[0094] While the above is a complete description of the preferred
embodiments of the invention, various alternatives, modifications,
and equivalents may be used. Therefore, the above description
should not be taken as limiting the scope of the invention which is
defined by the appended claims.
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