U.S. patent application number 15/679756 was filed with the patent office on 2017-11-30 for superhydrophobic coating for airway mucus plugging prevention.
The applicant listed for this patent is BOSTON SCIENTIFIC SCIMED, INC.. Invention is credited to CLAUDE O. CLERC, LAURA ELIZABETH FIRSTENBERG, SEAN P. FLEURY, GARY J. LEANNA, DANE T. SEDDON, PAUL SMITH, STEVEN E. WALAK, JAMES WELDON, MARK D. WOOD.
Application Number | 20170340782 15/679756 |
Document ID | / |
Family ID | 51531286 |
Filed Date | 2017-11-30 |
United States Patent
Application |
20170340782 |
Kind Code |
A1 |
FLEURY; SEAN P. ; et
al. |
November 30, 2017 |
Superhydrophobic Coating For Airway Mucus Plugging Prevention
Abstract
A method for reducing mucus accumulation in an airway including
disposing an implantable device within an airway, wherein the
implantable device has a first end, a second end, and an inner
surface defining a lumen extending from the first end to the second
end; wherein at least a portion of the inner surface has a
hydrophobic polymer coating thereon, wherein a polymer coating
surface has dynamic water contact angles of 145 degrees or greater;
and wherein the implantable device is constructed and arranged to
maintain patency of the airway; wherein accumulation of mucus is
reduced as compared to a similar implantable device without the
hydrophobic portion of the inner surface. An implantable medical
device having a superhydrophobic surface and a method of making an
implantable medical device having a superhydrophobic surface are
also provided. An implantable medical device having a
micropatterned surface with enhanced adhesion to tissue, optionally
in combination with other region(s) having a superhydrophobic
surface and a method of making such a device. Methods and devices
for prevention of bacterial adhesion to implanted medical
devices.
Inventors: |
FLEURY; SEAN P.;
(Minneapolis, MN) ; WOOD; MARK D.; (Sterling,
MA) ; SEDDON; DANE T.; (Boston, MA) ;
FIRSTENBERG; LAURA ELIZABETH; (Framingham, MA) ;
SMITH; PAUL; (Smithfield, RI) ; LEANNA; GARY J.;
(Holden, MA) ; CLERC; CLAUDE O.; (Marlborough,
MA) ; WELDON; JAMES; (Newton, MA) ; WALAK;
STEVEN E.; (Natick, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BOSTON SCIENTIFIC SCIMED, INC. |
Maple Grove |
MN |
US |
|
|
Family ID: |
51531286 |
Appl. No.: |
15/679756 |
Filed: |
August 17, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14210612 |
Mar 14, 2014 |
9764067 |
|
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15679756 |
|
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61799312 |
Mar 15, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2250/0039 20130101;
A61L 31/10 20130101; A61F 2230/0067 20130101; A61L 31/14 20130101;
A61F 2250/0051 20130101; A61L 2400/12 20130101; A61L 31/10
20130101; A61L 2400/18 20130101; A61L 31/10 20130101; A61F 2/0077
20130101; A61F 2002/043 20130101; A61F 2250/0056 20130101; A61F
2/86 20130101; C08L 27/18 20130101; A61F 2/07 20130101; C08L 23/12
20130101; A61F 2230/0091 20130101; A61F 2/82 20130101; A61F
2250/0026 20130101 |
International
Class: |
A61L 31/14 20060101
A61L031/14; A61F 2/82 20130101 A61F002/82; A61L 31/10 20060101
A61L031/10; A61F 2/07 20130101 A61F002/07; A61F 2/00 20060101
A61F002/00 |
Claims
1. A method for reducing mucus accumulation in an airway,
comprising: disposing an implantable device within an airway,
wherein the implantable device includes: a stent having a first
end, a second end, an inner surface defining a lumen extending from
the first end to the second end, and an outer surface; and a
polymer coating disposed on the inner surface of the stent, the
polymer coating including a radially inward facing superhydrophobic
surface having dynamic water contact angles of 145 degrees or
greater; wherein the superhydrophobic surface of the polymer
coating reduces mucus buildup on the implantable device.
2. The method of claim 1, wherein the polymeric coating further
comprises an anti-migration micropattern on the outer surface of
the stent.
3. The method of claim 2, wherein the anti-migration micropattern
includes pillars and holes between the pillars extending through
the polymeric coating.
4. The method of claim 3, wherein the holes are between 0.3 microns
and 20 microns across.
5. The method of claim 3, wherein the holes are between 1 micron
and 10 microns across.
6. The method of claim 2, wherein the anti-migration micropattern
includes a first anti-migration end region proximate the first end
and a second anti-migration end region proximate the second end,
the first end region being spaced apart from the second end
region.
7. The method of claim 1, wherein the polymer coating and the stent
are formed as an integral construction.
8. The method of claim 1, wherein the superhydrophobic surface
covers the inner surface entirely.
9. The method of claim 1, wherein the superhydrophobic surface
includes a plurality of protrusions extending from a base of the
polymeric coating.
10. The method of claim 9, wherein the plurality of protrusions
have a width of 25-50 microns, a height of 100-200 microns, and are
spaced 50-100 microns apart.
11. The method of claim 9, wherein the plurality of protrusions
have a width of 50 microns, a height of 150 microns, and are spaced
100 microns apart.
12. A method for reducing mucus accumulation in an airway,
comprising: disposing an implantable device within an airway,
wherein the implantable device includes a stent having a first end,
a second end, and an inner surface defining a lumen extending from
the first end to the second end; wherein at least a portion of the
inner surface has a hydrophobic polymer coating thereon, wherein
the polymer coating has a surface having dynamic water contact
angles of 145 degrees or greater; and wherein the implantable
device is constructed and arranged to maintain patency of the
airway; wherein accumulation of mucus is reduced as compared to a
similar implantable device without the hydrophobic polymer coating
on the inner surface.
13. The method of claim 12, wherein the hydrophobic polymer coating
comprises a superhydrophobic micropattern formed on the surface
thereof.
14. The method of claim 13, wherein the superhydrophobic
micropattern includes a plurality of protrusions extending from a
base of the hydrophobic polymeric coating.
15. The method of claim 14, wherein the plurality of protrusions
have a width of 25-50 microns, a height of 100-200 microns, and are
spaced 50-100 microns apart.
16. The method of claim 14, wherein a spacing between adjacent
protrusions of the plurality of protrusions is two times or more
than a width of an individual protrusion of the plurality of
protrusions.
17. The method of claim 12, wherein the hydrophobic polymeric
coating further comprises an anti-migration micropattern on the
outer surface of the stent.
18. The method of claim 17, wherein the anti-migration micropattern
includes pillars and holes between the pillars.
19. The method of claim 12, wherein the airway is a pulmonary
airway.
20. The method of claim 19, wherein the pulmonary airway is a main
bronchus or a trachea.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/210,612, filed Mar. 14, 2014, which claims
the benefit of provisional U.S. patent application Ser. No.
61/799,312, filed Mar. 15, 2013, which are hereby incorporated by
reference in their entirety.
[0002] The following patent applications are incorporated herein by
reference, each in its entirety:
[0003] U.S. Patent Application Ser. No. 61/798,685 (Firstenberg et
al.), entitled ANTI-MIGRATION MICROPATTERNED STENT COATING, filed
on Mar. 15, 2013;
[0004] U.S. Patent Application Ser. No. 61/798,897 (Seddon et al.),
entitled ANTI-MIGRATORY STENT COATING, filed on Mar. 15, 2013;
[0005] U.S. Patent Application Ser. No. 61/798,794 (Clerc),
entitled DELIVERY DEVICE FOR PARTIALLY UNCONSTRAINED
ENDOPROSTHESIS, filed on Mar. 15, 2013;
[0006] U.S. Patent Application Ser. No. 61/798,545 (Leanna et al.),
entitled MEDICAL DEVICES HAVING MICROPATTERN, filed on Mar. 15,
2013; and
[0007] U.S. Patent Application Ser. No. 61/798,991 (Bertolino et
al.), entitled BIOPSY TOOL HAVING MICROPATTERN, filed on Mar. 15,
2013.
FIELD
[0008] This disclosure relates to a method for reducing mucus
accumulation in an airway, an implantable device, and a method of
making the implantable device.
BACKGROUND
[0009] Implantable devices have been implanted in, for example,
airways to treat respiratory diseases. However, accumulation of
mucus at the superior and inferior ends of an implantable device
(e.g., a stent, an airway stent, etc.) has been a concern. Examples
of stents include those disclosed in U.S. Pat. No. 4,655,771
(Wallsten), U.S. Pat. No. 5,662,713 (Andersen et al.), U.S. Pat.
No. 5,876,448 (Thompson et al.), and U.S. Patent Application Pub.
No. 2012/0035715 (Robida et al.).
[0010] Proper mucus secretion is useful for clearing foreign matter
from the respiratory system. Mucus may include a mixture of
materials including, for example, water and glycoproteins and may
be produced by, for example, serous cells, goblet cells, Clara
cells, and type II alveolar cells in the bronchials and trachea.
Stretching of the cells initiates signaling pathways from the CNS
to secrete the mucus while the mechanical forces of the cilia and
air flow work to transport the mucus through the airway to be
expelled from the body.
[0011] Accumulation of mucus in an airway is not desirable. For
example, accumulation of mucus may result in an infection or
inflammation of tissue near the accumulation. Transport of mucus
through an airway is dependent on a number of factors including,
but not limited to, the composition and properties of the mucus,
the quantity of accumulated mucus, the degree of adherence of the
mucus to the walls of the airway, the dimensions and configuration
of the airway (e.g., cross-sectional area), and the linear velocity
of air flowing through the airway due to breathing, coughing, etc.
For a given volumetric flow rate of air, the velocity will be
higher at portions of the airway having a smaller cross-sectional
area and lower at portions of the airway with a larger
cross-sectional area. Airway stents have been designed to have a
sufficient amount of radial force to maintain patency in the
airway. Thus, reducing the cross sectional area in or near the
stent ends (e.g., radial compression of the airway) to help prevent
mucus buildup may be counterproductive with respect to the
objective of maintaining patency.
[0012] Some patients that have respiratory diseases have been given
a stent for palliative purposes. The presence of a rigid prosthesis
may, in some circumstances, have a detrimental effect on the
airway's ability to expel the mucus discussed below. As mucus moves
through a stented airway, it has a tendency to accumulate at the
ends of the stent. This may be due to a number of factors including
the inability of the trachea/bronchi to compress enough to produce
an airflow with sufficient force or velocity to move the mucus
through the stented area because, e.g., the stent may prevent or
inhibit radial compression or other constriction of the airway.
[0013] Some stents include a coating (e.g., a polymer coating) that
can act as a barrier to tumor ingrowth. However, the choice of
material and/or surface structure of the coating can influence, for
example, the adherence of mucus to the coating.
[0014] Some attempts have been made to reduce accumulation of mucus
in stents. For example, lubricious hydrophilic coatings of stent
inner lumens have been formulated for the purpose of promoting
mucus transport and to aid in the prevention of mucus buildup.
(See, e.g., Merit.TM. Aero.RTM.. fully covered tracheobronchial
stent at http://endotek.merit.com/products/pulmonary.aspx (last
visited Mar. 13, 2013).) However, in some circumstances, the use of
hydrophilic materials has promoted mucus attachment, thereby
increasing mucus accumulation, as well as the likelihood of airway
plugging and infection.
[0015] Thus, there exists a desire for improved medical devices
that reduce or eliminate one or more deficiencies of previous
medical devices. For example, improved medical devices that reduce
accumulation of mucus in a stented airway are desired. Improving
one or more of the factors that facilitate movement of mucus
through an airway may be useful to reduce or eliminate mucus
accumulation. Improved medical devices that reduce or prevent mucus
attachment and/or accumulation and thus reduce or eliminate the
likelihood of an infection are desired.
[0016] The issue of mucous transport is one of many issues
associated with placing an implant inside the body. Another issue
associated with placing an implant inside the body is the patient's
risk for infection, and or allergic reactions. Typically, given the
nature of processing medical device components, the surface energy
of such components is generally fairly high allowing most bodily
fluids to wet on them. This can cause bacterial cultivation leading
to infection.
[0017] It would be desirable to provide a medical device for
implantation in the body that has been engineered to reduce the
risk of infection and/or allergic reaction.
[0018] Yet another issue associated with placing an implant inside
the body involves adhering the implant to the surrounding tissue.
There is a need to provide implanted devices with features which
will prevent the implant from migrating or at least reduce any
possible migration.
[0019] Without limiting the scope of the present disclosure, a
brief summary of some of the claimed embodiments of the present
disclosure is provided below. Additional details of the summarized
embodiments and/or additional embodiments of the present disclosure
can be found in the detailed description.
[0020] A brief abstract of the technical disclosure in the
specification is provided as well for the purposes of complying
with 37 C.F.R. 1.72. The abstract is not intended to be used for
interpreting the scope of the claims.
[0021] All US patents and applications, and all other published
documents mentioned anywhere in this application, are incorporated
herein by reference, each in its entirety.
SUMMARY
[0022] In one or more aspects of the present disclosure, a method
for reducing mucus accumulation in an airway may include disposing
an implantable device (e.g., a stent, etc.) within an airway (e.g.,
a pulmonary airway, a main bronchus, a trachea, etc.), wherein the
implantable device has a first end, a second end, and an inner
surface defining a lumen extending from the first end to the second
end. In one or more embodiments, at least a portion of the inner
surface may be hydrophobic (e.g., may include a superhydrophobic
microstructure) and has dynamic water contact angles of 145 degrees
or greater. In one or more embodiments, the implantable device may
be constructed and arranged to maintain patency of the airway and
accumulation of mucus may be reduced as compared to a similar
implantable device without the hydrophobic portion of the inner
surface.
[0023] In another aspect of the present disclosure, an implantable
medical device may include an airway stent having a first end, a
second end, and an inner surface defining a lumen extending from
the first end to the second end. In one or more embodiments, a
coating may be disposed over at least a portion of the inner
surface, wherein a coating surface may be hydrophobic (e.g.,
superhydrophobic) and has dynamic water contact angles of 145
degrees or greater (e.g., at least 160 degrees, from 160 degrees to
170 degrees, etc.). In one or more embodiments, the implantable
medical device may have reduced adhesion with aqueous material and
mucus material as compared to a similar stent without the coating.
In at least one embodiment, the airway stent may be structured and
arranged to maintain the patency of an airway. In one or more
embodiments, a hydrophobic coating surface may be disposed
proximate (e.g., near) at least one of the first and second end and
may even extend from the first end to the second end.
[0024] In one or more aspects of the present disclosure, a method
for promoting transport of mucus in an airway may include disposing
an implantable medical device as described herein in an airway. In
another aspect of the present disclosure, a method for reducing
inflammation at an implantation site may include disposing an
implantable medical device as described herein at an implantation
site in an airway.
[0025] In another aspect of the present disclosure, a method for
making an implantable device having a superhydrophobic surface may
include providing an airway stent having a first end, a second end,
and an inner surface defining a lumen extending from the first end
to the second end. The method may also include disposing on the
airway stent a surface that is hydrophobic (e.g., superhydrophobic)
and has dynamic water contact angles of 145 degrees or greater. In
one or more embodiments, disposing a hydrophobic surface on the
airway stent may include disposing a polymer coating on at least
the inner surface of the airway stent and forming a hydrophobic
microstructure on the coating by one or more techniques including
laser ablation, photolithography-based microfabrication,
solidification of melted alkylketene dimer, microwave plasma
enhanced chemical vapor deposition of trimethoxylmethoxysilane,
phase separation, and domain selective oxygen plasma treatment. In
one or more embodiments, disposing a hydrophobic surface on the
airway stent may include disposing a polymer coating on at least
the inner surface of the airway stent and forming a hydrophobic
microstructure on the coating by one or more techniques including
roughening an outer surface of a mandrel, placing an airway stent
on the mandrel, applying a polymeric material to the airway stent
and mandrel, and curing the polymeric material to form the
hydrophobic surface (e.g., superhydrophobic) in the form of an
airway stent coating.
BRIEF DESCRIPTION OF THE FIGURES
[0026] The present disclosure and the following detailed
description of certain embodiments thereof can be understood with
reference to the following figures:
[0027] FIG. 1 is a schematic of a medical device.
[0028] FIG. 2 is a cross-section of the medical device of FIG. 1
taken along 2-2.
[0029] FIGS. 3 and 4 depict a drop on a surface.
[0030] FIG. 5 shows a perspective view of a medical device.
[0031] FIG. 6A shows a schematic of a stent.
[0032] FIG. 6B shows a micropattern with protrusions.
[0033] FIG. 6C shows a micropattern with drainage holes.
[0034] FIG. 7 shows a schematic of a stent with a micropattern of
pillars.
[0035] FIG. 8 shows a pancreatic stent with a micropattern.
[0036] FIG. 9 shows a schematic of a stent.
[0037] FIGS. 10-14 show schematics of various sleeves for the
jejunum.
DETAILED DESCRIPTION
[0038] While the subject matter of the present disclosure can be
embodied in many different forms, specific embodiments of the
present disclosure are described in detail herein. This description
is an exemplification of the principles of the present disclosure
and is not intended to limit the present disclosure to the
particular embodiments illustrated.
[0039] For the purposes of this disclosure, like reference numerals
in the figures, shall refer to like features unless otherwise
indicated.
[0040] Various aspects of the present disclosure are depicted in
the figures. Elements depicted in one figure can be combined with
and/or substituted for elements depicted in another figure, as
desired.
[0041] In one or more aspects of the present disclosure, a method
for reducing mucus accumulation in an airway includes disposing an
implantable device within an airway. In one or more embodiments,
the implantable device includes an airway stent (e.g., an airway
stent) and is constructed and arranged to maintain patency of an
airway. In one or more embodiments, the airway in which the
implantable device may be disposed can be a main bronchus, a
trachea, and/or any other location within an airway, without
limitation.
[0042] In one or more embodiments, with reference to FIG. 1, an
implantable device, shown schematically at 20 can include a stent
40 having an inner surface 49, an outer surface 44, a first end 46,
and a second end 48. Lumen 47 extends from the first end 46 to the
second end 48. As shown in FIG. 2, a cross-section of FIG. 1, inner
surface 49 has a coating 50 thereon. Coating 50 has a coating inner
surface 52.
[0043] The implantable device shown schematically in FIGS. 1 and 2
may be self-expanding, balloon expandable, or hybrid expandable.
Embodiments of the medical device may have a constant diameter,
tapers, flares and/or other changes in diameter in the body (e.g.,
between the ends) and/or at an end.
[0044] In some embodiments, the medical device may include a stent
having a coating on the interior surface and, optionally, the outer
surface. In some embodiments, the medical device may include a
stent having a liner on the inner surface and, optionally, the
outer surface.
[0045] Coating 50 may be disposed about at least a portion of the
inner surface 49 and, typically, the entire inner surface. In at
least one embodiment, the coating 50 substantially covers the
entire inner surface 49 of the expandable stent 40. In other
embodiments, the coating 50 covers less than the entirety of the
inner surface 49 of the expandable stent 40.
[0046] As shown in FIG. 2, the coating 50 can be directly connected
to the inner surface 49 of the expandable stent 40. In one or more
embodiments, the polymeric coating 50 can be connected to the inner
surface 49 of the expandable stent 40 using an adhesive or other
means of attaching the coating to the device. In at least one
embodiment, the coating at least partially covers the outer surface
44 also. In at least one embodiment, partial coverage can include
partial coverage of the perimeter and/or the length. In some
embodiments, the coating 50 and the stent 40 can be integral (e.g.,
collectively formed as an integral construction). For example, in
one or more embodiments in which at least a portion a stent 40 is
made of a material (e.g., silicone, silicone coating, biocompatible
polymer or metal, etc.) appropriate for micropatterning, then the
micropattern may be directly incorporated into the structure of the
stent 40 (e.g., the stent 40 and polymer coating 50 having a
micropattern can be integrally formed).
[0047] In one or more embodiments, at least a portion of the inner
surface has a hydrophobic polymer coating thereon, wherein a
polymer coating surface has dynamic water contact angles of 145
degrees or greater. For example, a stent may have a polymer coating
thereon, wherein a polymer coating surface has dynamic water
contact angles of 145 degrees or greater. In some embodiments, the
water contact angles may be greater than 150 degrees, greater than
160 degrees, greater than 165 degrees, or greater than 170 degrees.
In some embodiments, the water contact angle may be from 150
degrees to 175 degrees, from 150 degrees to 170 degrees, from 160
degrees to 170 degrees, etc. The water contact angle (i.e., the
angle at which a liquid meets a surface) is illustrated in FIGS. 3
and 4. FIGS. 3 and 4 show a drop 62 on a surface 64. The water
contact angle is shown in FIG. 3. In FIG. 3, angle is less than 90
degrees whereas in FIG. 4, water contact angle is 145 degrees. The
sessile drop technique as described in standard surface chemistry
textbooks is suitable for measuring a static or a dynamic water
contact angle.
[0048] In one or more methods of the present disclosure,
accumulation of mucus is reduced as compared to a similar
implantable device without the hydrophobic portion of the inner
surface. That is, in a comparison of (1) a given implantable device
having a hydrophobic coating surface thereon with (2) the same
device lacking the hydrophobic coating surface, the former would be
have a reduced accumulation of mucus (e.g., when implanted in an
airway of a patient).
[0049] For purposes of the present disclosure, a hydrophobic
surface is one that has a static water contact angle of greater
than 90 degrees. A superhydrophobic surface is one what has a
dynamic (receding or advancing) water contact angle greater than or
equal to 145 degrees.
[0050] In one or more embodiments, the hydrophobic polymer coating
50 includes a superhydrophobic microstructure formed on the polymer
coating surface 52. Exemplary superhydrophobic microstructures may
include those described in Weber (U.S. Patent Application Publ. No.
2007/0005024 A1 (Weber et al.)) and the documents cited therein,
all of which are incorporated herein by reference, each in its
entirety.
[0051] In one or more methods of the present disclosure, disposing
the implantable device within the airway includes disposing the
implantable device within a pulmonary airway. Any of a wide variety
of delivery methods, without limitation, may be suitable to dispose
an implantable device within an airway. Any of a wide variety of
stent delivery devices may be suitable to dispose an implantable
device within an airway.
[0052] An implantable device of the present disclosure may be
implanted (e.g., deployed) within any pulmonary airway (e.g., a
main bronchus, a trachea, etc.).
[0053] In one or more aspects of the present disclosure, an
implantable medical device can include an airway stent and a
coating disposed over at least a portion of the airway stent inner
surface. In at least one embodiment, the airway stent is
constructed and arranged to maintain the patency of an airway
(e.g., an airway lumen, such as a main bronchus or trachea).
[0054] In at least one embodiment, a coating surface 52 is
hydrophobic and has dynamic water contact angles of 145 degrees or
greater (e.g., 150 degrees or greater, 160 degrees or greater, 165
degrees or greater, 170 degrees or greater, from 150 degrees to 175
degrees, from 150 degrees to 170 degrees, from 160 degrees to 170
degrees, etc.). In one or more embodiments, due at least in part to
the superhydrophobicity of the coating surface 52, an implantable
medical device (e.g., an airway stent) has reduced adhesion with
aqueous material and mucus material as compared to a similar stent
without the coating 50 (e.g., without the coating surface 52).
[0055] As described herein, mucus may tend to accumulate in the
vicinity of stent ends. To reduce mucus accumulation, it may be
useful to position a hydrophobic coating surface 52 near at least
one of the first end and the second end. For example, a coating
surface may longitudinally extend from the first end 46 to the
second end 48. In one or more embodiments, the coating surface 52
may longitudinally extend from either the first end 46, the second
end 48, or both for a longitudinal distance of less than 50% of the
airway stent length (e.g., less than 40%, less than 30%, less than
20%, less than 10%, etc.). In at least one embodiment, the polymer
coating 50 (e.g., the hydrophobic coating surface 52) covers
substantially all of the inner surface of the stent 40 (i.e., from
the first end 46 to the second end 48).
[0056] One or more aspects of the present disclosure relates to a
method for promoting transport of mucus in an airway. The method
includes disposing an implantable medical device (e.g., implantable
medical device 20), as described herein, in an airway.
[0057] One or more aspects of the present disclosure relates to a
method for reducing inflammation at an implantation site. The
method includes disposing an implantable medical device (e.g.,
implantable medical device 20), as described herein, in an airway.
In one or more embodiments, a reduction of accumulation of mucus at
the implantation site (e.g., an airway) can cause a resultant
reduction of inflammation of the implantation site tissue,
particularly at or near the ends of the implantable medical
device.
[0058] One or more aspects of the present disclosure relates to a
method for making an implantable device having a superhydrophobic
surface. The method includes providing an airway stent having a
first end, a second end, and an inner surface defining a lumen
extending from the first end to the second end. The method further
includes disposing on the inner surface of the airway stent a
surface that is hydrophobic and has dynamic water contact angles of
145 degrees or greater.
[0059] In one or more embodiments, disposing on the airway stent or
any other stent or suitable medical device a surface may include
attaching (e.g., adhering, bonding, connecting, etc.) a polymer
coating that has a polymer coating surface that is
superhydrophobic. In one or more embodiments, the method includes
disposing a polymer coating 50 on at least the inner surface of the
airway stent 40 and forming a superhydrophobic microstructure on
the coating 50. Forming a superhydrophobic microstructure on the
coating may be accomplished any of a wide variety of techniques
including, but not limited to, laser ablation,
photolithography-based microfabrication, solidification of melted
alkylketene dimer, microwave plasma-enhanced chemical vapor
deposition of trimethoxylmethoxysilane, phase separation, and
domain selective oxygen plasma treatment. The method may
alternatively include roughening an outer surface of a mandrel,
depositing polymer material on the mandrel, placing the polymer
material on an airway stent or any other stent or suitable medical
device so that the inner surface of the stent or medical device
contacts the polymer material, such that the polymer material is
transferred to the inner surface of the stent.
[0060] In one or more embodiments, mucus transport may be promoted
by, for example, reducing the surface energy of an airway lumen
wall, such as an interior surface of an airway stent coating.
Because as mentioned herein, mucus transport depends at least in
part on the adherence of the mucus to the airway lumen wall,
providing a superhydrophobic surface on the interior surface (e.g.,
inner surface of the airway stent or other stent, inner surface of
a stent coating, etc.) should facilitate mucous transport.
[0061] In one or more embodiments, the hydrophobic coating may be
applied on all or a portion of the inner surface of a stent
coating. In some embodiments, the hydrophobic coating may be
present on the inner surface of a stent, but not the outer surface
of the stent where a hydrophobic coating may promote undesirable
stent migration. However, because stent migration may be otherwise
controlled by any manner known to one of skill in the art (e.g.,
use of fixation anchors, barbs, flares, etc.), the present
disclosure contemplates use of the hydrophobic coating on any or
all surfaces of a stent, including the outer surface.
[0062] Although not wishing to be bound by theory, surface energy
or wettability quantifies the disruption of intermolecular bonds
that form when a surface is created. Wettability may be
demonstrated by a contact angle measurement of a drop of water on
the surface. For example, when the contact angle is small (e.g.,
below 45 degrees) the surface material is said to be hydrophilic
and thus can provide a surface that has good wettability (droplet
spreads out on surface). When the contact angle is above 90degrees,
for example, the surface material is said to be hydrophobic and
thus has poor wettability (e.g., the surface repels liquids,
droplets remains spherical).
[0063] Thus, a hydrophobic coating having poor wettability may
reduce or prevent mucus buildup, relative to a hydrophilic coating
that has high wettability.
[0064] In some embodiments, even the hydrophobic materials may
accumulate mucus to some extent. In one or more embodiments, a
superhydrophobic coating may further reduce the accumulation of
mucus.
[0065] In at least one embodiment, a micropatterned polymer coating
can be applied to a stent or other suitable medical device to
create a super hydrophobic surface (e.g., lowering the surface
energy of the surface of the stent to the extent that the dynamic
water contact angle created is 145 degrees or greater) that can be
useful in that the surface promotes fluid movement (e.g., fluids
such as mucus and water are less likely to attach to the stent,
which helps reduce or prevent inflammation, granulation tissue
formation, and/or mucous plugging) and is self-cleaning (e.g.,
bacteria has greater affinity for aqueous fluids and leave the
stent surface with droplets of aqueous fluids as they roll
off).
[0066] A lotus leaf is a natural example of a surface that is
superhydrophobic. Although not wishing to be bound by theory, the
increased ability of a lotus leaf to repel water depends in part on
architecture of the lotus leaf surface. On a microscopic or
nanoscopic scale, the surface of the lotus leaf includes
closely-packed papillae structures. The spacing of these papillae
allows a large extent of air trapping when contacting a liquid such
as water. The microstructure present on the lotus leaf surface, in
conjunction with the low surface energy of the lotus leaf material,
provides a superhydrophobic surface having a contact angle upwards
of 160-170 degrees. This, in conjunction with the already low
surface energy of the material creates a superhydrophobic surface
with a contact angle of at least 145 degrees or more, and
desirably, upwards of 160-170 degrees. Superhydrophobicity, in some
embodiments, may also create a self-cleaning surface as
demonstrated by the lotus leaf.
[0067] In comparison, upon contact with water, polypropylene's
contact angle has been reported to be about 105 degrees, silicone's
contact angle has been reported to be about 110 degrees, PET's
contact angle has been reported to be about 75 degrees,
polyurethane's contact angle has been reported to be about 85
degrees, and PTFE's contact angle has been reported to be about 115
degrees.
[0068] Numerous methods of producing superhydrophobicity of a
polymer surface have been developed. For example, in one or more
embodiments, a microstructure may be etched on a coating
surface.
[0069] In one or more embodiments, a superhydrophobic polymer
coating may be manufactured by laser etching a pattern on a coating
mandrel, placing a stent on the mandrel, dipping or spraying the
stent, and allowing the coating to mimic the pattern and cure in
that formation. In at least one embodiment, the superhydrophobic
coating can be manufactured by roughening the surface of a mandrel
with sand paper.
[0070] In one or more embodiments, a microstructure can be created
by coating a stent or other suitable medical device on a standard
mandrel and performing a secondary operation on the inner diameter
of the stent or other suitable medical device (e.g., laser
ablation, photolithography-based microfabrication, solidification
of melted alkylketene dimer, microwave plasma-enhanced CVD of
trimethoxylmethoxysilane, phase separation, or domain-selective
oxygen plasma treatment (surface doping within a plasma treatment
chamber), etc.).
[0071] The following documents relate to techniques for
manufacturing a micropatterned surface, each of which is
incorporated by reference in its entirety: Kroetch, "NanoFab's PDMS
Microfluidic Device Fabrication Manual," September 2004, 8 pgs.
(available online at
http://www.nanofab.ualberta.ca/wp-content/uploads/2009.03/boxedpdms.pdf,
last accessed Mar. 10, 2013); Dodou et al., "Mucoadhesive
micropatterns for enhanced grip," Conf. Proc. IEEE Eng. Med. Biol.
Soc., 2007; 2007:1457-62; Kwon et al., "Friction enhancement via
micro-patterned wet elastomer adhesives on small intestinal
surfaces," Biomed. Mater., 2006 December; 1(4):216-20; Tooley et
al., "Thermal fracture of oxidized polydimethylsiloxane during soft
lithography of nanopost arrays," J. Micromech. Microeng., 2011,
21:054013 (9 pgs.); and Desai et al., "Plastic masters-rigid
templates for soft lithography," Lab Chip, 2009 Jun. 7;
9(11):1631-7.
[0072] In one or more embodiments, the microstructure may be
designed having topology and dimensions that are similar to the
papillae of a lotus leaf. In at least one embodiment, the stent
having a superhydrophobic polymer coating will have a reduced
surface energy (e.g., relative to a polymer coating lacking a
microstructure) resulting in reduced mucus buildup in the
airway.
[0073] Articles having superhydrophobic surfaces are described by
Weber et al. (U.S. Patent Application Pub. No. 2007/0005024 A1),
Gelbart et al. (U.S. Patent Application. Pub. No. 2008/0226694 A1),
and Edin (U.S. Pat. No. 8,043,359), Privett et al. (PCT Int'l
Patent Application WO 2012/167017 A2), Atanasoska et al. (U.S.
Patent Application Pub. No. 2009/0294732), Taton et al. (PCT Int'l
Patent Application Pub. No. WO 2010/033482), and Jin et al. (PCT
Int'l Patent Appliation Pub. No. WO 2010/022107), each of which is
incorporated by reference in its entirety. In particular,
techniques for providing superhydrophobic surfaces are provided at
paragraphs [0040]-[0063] of Weber et al. (U.S. Patent Application
Pub. No. 2007/0005024), incorporated by reference herein.
[0074] In one or more embodiments, a stent having a hydrophobic
coating can be useful in reducing mucus accumulation and related
complications (e.g., infection, inflammation, etc.).
[0075] In one or more embodiments, a micropatterned polymer coating
may be applied to a medical device (e.g., an implantable medical
device) in order to, for example, reduce the interaction of medical
device materials with biological tissue that may experience an
inflammatory and/or allergic response. In particular, a
hypoallergenic micropatterned polymer coating may be useful when
the coating is a component of a medical device (e.g., an
implantable medical device) that may spend a duration of time in
contact with biological tissue (e.g., a mucosal wall).
[0076] Application of a micropatterned polymer coating on a medical
device may be accomplished by, for example, a chamber-style process
in order to treat all exposed surfaces with either a micropatterned
polymer coating or utilizing a doped plasma chamber to create
microstructure on the surface of a medical device material (e.g.,
an alloy, etc.). For example, a portion of a medical device is
depicted in FIG. 5 wherein a superhydrophobic coating or etching
may be performed on all surfaces of the medical device. Hemostasis
clip 200 includes tube 210 with an outer surface 212 and an inner
surface 214. One or more arms 216 extend from the tube. Arms 216
have an outer surface 217 and an inner surface 216. A
superhydrophobic coating may be disposed on the exterior and/or
interior of tube 210 and/or on the outer surface and/or inner
surface of arms 216. The entirety of one or more surfaces may be
provided with a superhydrophobic coating or a portion which is less
than the entirety of the surface may be provided with such a
coating. More desirably, the arms have an outer surface with a
superhydrophobic coating to facilitate movement in and out of the
tube and an inner surface with an antimigratory coating to
facilitate grasping.
[0077] The medical device can be a stent, a catheter, a valve, a
clip, a closure device, or any other suitable medical device which
is placed in the body or implanted in the body.
[0078] In one or more embodiments, a micropatterned polymer coating
is disposed on some, but not all, of the surfaces of a medical
device.
[0079] Micropatterned polymer coatings may be formed from and/or
include one or more of a wide variety of polymers including, but
not limited to polytetrafluoroethylene (PTFE), polypropylene,
acrylic polymers and nitrile butadiene. All of these polymers may
be deposited in a manner which may decrease surface energy to a
level of hydrophobicity and desirably, superhydrophobicity. In
addition, the hypoallergenic nature of these polymers may be useful
when covering materials (e.g., alloys) known to cause allergic
reactions.
[0080] The present disclosure is also directed to the use of a
micropatterned structure on an implantable medical device to
provide different sections or levels of adhesiveness to the lumen
wall. Devices provided with such a micropatterned structure may be
used in any suitable lumen, or passageway in the body, including
the airway.
[0081] Research has been conducted in the area of using
micropatterned adhesives in wet biological applications. For
example, applications of this research include endoscopic robots
and biodegradable tissue adhesives. (See, e.g., Lotters et al.,
"The mechanical properties of the rubber elastic polymer
polydimethylsiloxane for sensor applications," J. Micromech.
Microengineering, 1997, 7(3):145-147; Axisa et al., "Low cost,
biocompatible elastic and conformable electronic technologies using
MID in stretchable polymer," Conf. Proc. IEEE Eng. Med. Biol. Soc.,
2007; 2007:6593-6; Jeong et al., "Nanohairs and nanotubes:
Efficient structural elements for gecko-inspired artificial dry
adhesives," Nano Today, August 2009, 4(4):335-346; and Majidi,
"Enhanced Friction and Adhesion with Biologically Inspired Fiber
Arrays," University of California, Berkeley, Ph.D. thesis, May 15,
2007, 143 pgs, all of which are incorporated by reference, each in
its entirety) Although not wishing to be bound by theory, the
mechanism for micropattern attachment to tissue (e.g., the
digestive tract) may be based on the ability of the tissue to
conform to the micropatterned surface and interlock with it in
these applications. As a result, architectures have evolved to
less-closely resemble the hair-like structures found on the feet of
a gecko. For example, by decreasing pillar density and aspect
ratio, it is possible to achieve greater pillar-tissue interlock,
as discussed in Mandavi et al., "A biodegradable and biocompatible
gecko-inspired tissue adhesive," Proc. Natl. Acad. Sci. U.S.A.,
2008 Feb. 19; 105(7):2307-12, incorporated herein by reference in
its entirety.
[0082] Soft lithography techniques can also be used to produce the
disclosed device coating in general and stent coating in
particular. These methods involve accurately replicating micro- and
nano-scale features onto soft, elastomeric materials by casting
polymer over a micropatterned silicon wafer master mold. Consistent
and replicable micropillars have been produced this way. Additional
precautions, including double casting methods or use of interim
plastic masters, can also be taken to reduce the stress applied to
the micropillars during manufacture in order to better maintain
pillar integrity and overall pattern function.
[0083] Micropillars have been fabricated using a variety of
polymeric materials. Indeed, any polymeric material can be used to
create a micropatterned adhesive provided it is flexible enough
conform to the target tissue type and create an effective
interlock. In addition to providing anti-migration properties that
promote tissue interlock for increased traction against the lumen
wall, this micropattern can also be applied to the medical device
in general or stent in particular to create a super hydrophobic
surface. In essence, lowering the surface energy of the medical
device in general or stent in particular to the point where the
contact angle created is greater than 145 degrees or more, and,
more desirably, 150 degrees or more can provide a surface that
promotes fluid movement. To that end, as discussed above, mucus and
water is less likely to attach to a medical device or stent in
particular with such a surface which helps prevent inflammation,
granulation tissue formation, and mucus plugging. Such a surface
may also be self-cleaning. Because bacteria have a greater affinity
for water, it will latch onto droplets as the droplets roll off the
medical device in general and stent in particular.
[0084] The surface is desirably made of closely packed papillae
structures. The spacing of these papillae brings a large extent of
air trapping when contacting a liquid such as water. This, in
conjunction with the already low surface energy of the material
creates a superhydrophobic surface with a contact angle 145 degrees
or greater, more desirably 160 degrees or greater and even more
desirably, 170 degrees or greater. As discussed above, the
superhydrophobicity may also create a self-cleaning surface.
[0085] In one embodiment, a surface is engineered to reduce the
collection of bacteria thereon. Specifically, a superhydrophobic
surface is provided using any of the techniques disclosed herein.
The surface is desirably an inner surface of an airway stent or a
gastrointestinal stent. The surface may be of silicone or any
suitable material, polymeric or otherwise. The surface is,
optionally, in the form of a coating.
[0086] One way to accomplish this pattern is by laser etching the
specific pattern onto a coating mandrel. When the medical device in
general or stent in particular is placed on the mandrel and dipped
or sprayed, the coating will mimic the pattern and cure in that
formation. The pattern can also be accomplished by roughening the
surface of the mandrel with sand paper as well. Other ways to
create the microstructure involve coating the medical device in
general or stent in particular on a standard mandrel and then
performing a secondary operation on the inner and/or outer diameter
such as laser ablation, photolithography-based microfabrication,
solidification of melted alkylketem dimmer, microwave plasma
enhanced CVD of trimethoxylmethoxysilane, phase separation, or
domain-selective oxygen plasma treatment (surface doping within a
plasma treatment chamber).
[0087] It is within the scope of the present disclosure to combine
two patterns on the outside of the coating. As shown in FIG. 6A, an
anti-migration micropattern 308 is applied, by any of the means
described above, to the outer edges of the medical device in
general or stent 40 in particular. A superhydrophobic pattern 52 is
applied throughout the inner portion as shown in FIG. 6A.
Micropattern 308 on the outer edges will aid in migration
prevention. Interlocking the pattern with the mucosal wall will
create enhanced traction and keep the stent from moving out of
position, essentially promoting tissue ingrowth without the concern
of removability. The inner micropattern 52 will greatly aid in the
movement of fluid through that portion. This will help prevent any
excess buildup around the stent and allow proper clearance of mucus
and water. To further enhance this effect, micro sized holes can be
strategically placed within the pillars of the micropattern to
promote further fluid drainage.
[0088] Desirably, as shown in FIG. 6B, micropattern 52 will be in
the form of a plurality of protrusions, such as pillars 313.
Optionally, the micropattern may include one or more drainage holes
315 to facilitate fluid movement.
[0089] FIG. 6C shows a micropattern 52 with pillars 313 and
drainage holes 315. Desirably, the drainage holes will have opening
of from 10 microns to 20 microns across. Smaller or larger openings
may also be used. The pillars may be less than 1 micron across (for
example, 0.3 microns), or they may be from 1 to 10 microns across
or larger. The holes may be used to drain mucus or other fluids to
allow traction to be maintained during fluidic exchange.
[0090] The micropattern shown in FIG. 6C may be applied on the
surface, desirably, the outer surface, of a stent, for example, a
braided or other stent, to allow mucus through the stent and
maintain traction on the outside of the stent.
[0091] This treatment will also enhance stent flexibility through a
slippery surface and tissue ingrowth prevention. While it helps
with fluid drainage as stated above, the extremely low surface
energy will also help prevent tissue ingrowth along the middle
portion of the stent. This will allow the stent to easily extend
and compress axially within the two anti-migration portions. This
is particularly useful for stents used in the trachea and bronchus
where movement occurs during a cough, swallow, and forced
ventilation. The ability of a stent to flex and match such movement
is important in preventing migration. A stiff stent is likely to
migrate when the trachea expands and contracts. If the stent is
flexible, it can move in conjunction with the trachea and be more
likely to remain in place.
[0092] The micropatterns may be applied to implantable medical
device other than stents for use in the respiratory system. It may
also be applied to stents that are placed in other vessels in the
body such as a biliary stent or an airway stent. With respect to a
biliary stent or airway stent, the pillars of the micropattern may
be oriented in one direction to increase anti-migratory effects.
For biliary/pancreatic stents, this could eliminate the need for
anti-migratory "pegs" that are cut from the stent wall. An example
of this is shown in FIG. 7. Stent 300, shown schematically in FIG.
7, includes a micropattern of pillars 304 which is oriented in one
direction. FIG. 8 shows pancreatic stent 300 with a micropattern
308.
[0093] In at least one embodiment, for example, that shown in FIG.
7, a micropattern may include protrusions (e.g., micropillars or
other suitable shapes) that are oriented in a direction that is not
perpendicular to a base. For example, one or more micropillars may
extend from a base a first distance from the base in a direction
perpendicular to the base and a second distance in a direction
parallel to the base. In one or more embodiments, the micropillars
are arranged in a diagonal configuration, wherein each micropillar
extends in a direction parallel to that of the other micropillars.
Herein, "one-way" micropattern includes a plurality of
microstructures that extend a first distance from the base in a
direction perpendicular to the base and a second distance in a
direction parallel to the base. In one or more embodiments, a
one-way micropattern may replace or supplement traditional
antimigration features on stents, such as pegs. The use of a
one-way microstructure can, in some embodiments, reduce trauma to a
body lumen wall while reducing or eliminating stent migration.
[0094] In one or more embodiments, the protrusions in the
superhydrophobic region may be spaced 100 microns apart and may be
50 microns wide and have a height of 150 microns. In other
embodiments, the protrusions in the superhydrophobic region may be
spaced 50-100 microns apart and may be 25-50 microns wide and have
a height of 100-200 microns. Typically, the spacing between
adjacent protrusions will exceed the width of the individual
protrusions, desirably by a factor of two or more. In other
embodiments, other sizes and spacing of protrusions may be
employed.
[0095] The present disclosure is also directed to a stent such as
that shown in FIG. 9. Stent 40 includes one or more regions 308
with a micropattern and/or an exposed stent having openings. As
shown in FIG. 9, stent 40 has regions 308 at both ends.
Micropattern 308 is arranged to provide in-growth. Region 309 is
provided with a superhydrophobic surface to prevent in-growth in
the region.
[0096] The present disclosure is further directed to a stent or
other suitable medical device with a dual coating. The outside is
provided with a high-friction and/or high adhesion region,
desirably to prevent migration. The inside is provided with a
surface arranged to prevent biofilm formation and/or bacteria
adhesion. The inner surface may be hydrophilic in some embodiments.
Desirably, however, it will be hydrophobic and more desirably,
superhydrophobic. The inner and/or outer surfaces may be in the
form of a coating.
[0097] The present disclosure is also directed to a stent,
typically plastic, with a micropattern on the outside to aid in
removal of the stent. The present disclosure is also directed to a
stent, typically plastic, with a micropattern on the outside to
help anchor it in the vessel.
[0098] The present disclosure is further directed to a stent with
an interior having one or more regions which are superhydrophobic.
This may be used, for example, to prevent bile buildup and/or to
lower the friction and/or deployment force. The increased contact
angle associated with the superhydrophobic region would enhance
drainage through the stent. Desirably, the superhydrophobic region
on the inner surface of the stent would lower tracking force as the
stent is delivered to its target site.
[0099] The present disclosure is also directed to applying a spray
which provides a micropatterned surface to the inner wall of a
vessel such as the esophagus or colon. Alternatively, a sleeve with
a micropatterned surface may be used. The micropatterned surface
may be any of those disclosed herein which provide for greater
adhesion to the surface of a bodily vessel. The spray or sleeve may
be used in conjunction with a stent. The stent optionally may be
provided with a similar micropattern to allow for adhesion to the
wall or to the sleeve. The interior of the stent optionally may be
provided with a superhydrophobic surface.
[0100] In one or more embodiments, a double layer micropattern
polymer coating may be formed by, for example, spray coating a
lining of a micropatterned mold (e.g., micropattern sphere such as
a Velcro ball, object) or a body lumen (e.g., an esophagus, a colon
wall, etc.) to fill the voids and contact wall, followed by
deploying a device (e.g., a stent) with a micropattern to connect
with (e.g., adhere to) the spray coat.
[0101] In another embodiment, the present disclosure is directed to
a jejunal liner which may be used, for example, to treat obesity.
The liner may be in the form of a sleeve that may be anchored in
the pylorus. The sleeve may prevent food absorption in the duodenum
and part of the jejunum. Any of the micropatterns (e.g., adhesive
micropatters, etc.) disclosed herein for reducing migration and/or
increasing adhesion may be provided to outer surface of the sleeve
to anchor the sleeve.
[0102] A number of embodiments for use in the jejunem are shown in
FIGS. 10-14. FIG. 10 shows a jejunal liner in the form of sleeve
500 with adhesive micropattern 513 on the outer surface at one end.
FIG. 11 shows another such sleeve 500 with adhesive micropattern
513 over the entirety of the outer surface. The sleeves of FIGS. 10
and 11 include an enlarged anchor portion at one end. FIG. 12 shows
a sleeve 500 with adhesive micropattern 513 over the entire outer
surface. The sleeve does not have an enlarged anchor portion. FIG.
13 shows a sleeve similar to that shown in FIG. 12, further
comprising a stent 40. FIG. 14 shows a sleeve with a micropattern
over only a portion of the sleeve.
[0103] These devices may also be used in the esophagus.
[0104] The sleeve may be adhered to the small intestine with a
balloon. It may, optionally, be located distally of the papilla of
Vaters.
[0105] The present disclosure is also directed to adjustable
gastric bands provided with micropatterns on the outer surface to
prevent migration. To that end, the band may be provided on the
outer surface with any of the anti-migration patterns disclosed
herein. As discussed above, these patterns have adhesive
properties. The inner surface of the band may be provided with
anti-adhesive micro-patterns which are used to prevent bacterial
and biofilm adhesion. Thus, the superhydrophobic surface disclosed
herein may be provided on an interior surface of the band. More
details about gastric bands may be found at least in U.S. Pat. No.
6,755,869 (Geitz).
[0106] Antiadhesive micropatterns may also be provided inside a
stent, inside a jejunal liner, outside a gastric balloon, or
outside any device inserted in the stomach to treat obesity.
Antiadhesive micropatterns may also be added to a tacky implant
material such as SIBS
(poly(styrene-block-isobutylene-block-styrene)), SIB S-PU
((poly(styrene-block-isobutylene-block-styrene)-polyurethane), or
silicone to reduce tackiness and prevent adhesion.
[0107] Additionally, an adhesive micro-pattern may be applied to a
device to maintain its location within an organ or subcutaneous
location such as a port described in U.S. Patent Application Pub.
No. 2009/0182303 A1 (Walak et al.) for the treatment of obesity. An
illustration of a port is shown in FIG. 15 of U.S. Patent
Application Pub. No. 2009/0182303 A1(Walak et al.). The
micro-pattern could be placed on the entire device or to elements
of the device such as leads to ensure contact or delivery of a drug
to the opposing tissue.
[0108] Additionally, an adhesive micro-pattern could be applied to
a pacer, therapeutic agent release device, or obesity filler to
maintain a position within the stomach or to join elements to form
a filler of the stomach cavity so that the patient feels full.
[0109] The present disclosure is also directed to methods of making
any of the medical devices disclosed herein as well as methods of
using such devices in the body. Typically, the device will be
delivered via catheter to a desired region of the body and
deployed. Catheters are well known in the art and described in U.S.
Pat. No. 6,071,273 (Euteneuer et al.), U.S. Pat. No. 6,733,487
(Keith et al.) and U.S. Pat. No. 6,254,609 (Vrba et al.).
[0110] A description of some embodiments of the present disclosure
is contained in the following numbered statements:
[0111] Statement 1. A method for reducing mucus accumulation in an
airway comprising:
[0112] disposing an implantable device within an airway, wherein
the implantable device has a first end, a second end, and an inner
surface defining a lumen extending from the first end to the second
end;
[0113] wherein at least a portion of the inner surface has a
hydrophobic polymer coating thereon, wherein a polymer coating
surface has dynamic water contact angles of 145 degrees or greater;
and
[0114] wherein the implantable device is constructed and arranged
to maintain patency of the airway;
[0115] wherein accumulation of mucus is reduced as compared to a
similar implantable device without the hydrophobic portion of the
inner surface.
[0116] Statement 2. The method of statement 1 wherein the
implantable device comprises a stent.
[0117] Statement 3. The method of statement 1 or statement 2
wherein the hydrophobic coating comprises a superhydrophobic
microstructure formed on the polymer coating surface.
[0118] Statement 4. The method of any one of statements 1-3 wherein
disposing the implantable device within the airway comprises
disposing the implantable device within a pulmonary airway.
[0119] Statement 5. The method of statement 4 wherein the pulmonary
airway is selected from the group consisting of a main bronchus and
a trachea.
[0120] Statement 6. An implantable medical device comprising:
[0121] an airway stent having a first end, a second end, and an
inner surface defining a lumen extending from the first end to the
second end;
[0122] a coating disposed over at least a portion of the inner
surface, wherein a coating surface is hydrophobic and has dynamic
water contact angles of 145 degrees or greater.
[0123] Statement 7. The implantable medical device of statement 6
wherein the implantable medical device has reduced adhesion with
aqueous material and mucus material as compared to a similar stent
without the coating.
[0124] Statement 8. The implantable medical device of statement 6
or statement 7 wherein the airway stent is structured and arranged
to maintain the patency of an airway.
[0125] Statement 9. The implantable medical device of any one of
statements 6-8 wherein the hydrophobic coating surface has dynamic
water contact angles of 150 degrees or greater.
[0126] Statement 10. The implantable medical device of any one of
claims 6-9 wherein the hydrophobic coating surface is near at least
one of the first end and the second end.
[0127] Statement 11. The implantable medical device of any one of
statements 6-10 wherein the hydrophobic coating surface extends
from the first end to the second end.
[0128] Statement 12. A method for promoting transport of mucus in
an airway comprising:
[0129] disposing an implantable medical device of any one of
statements 6-11 in an airway.
[0130] Statement 13. A method for reducing inflammation at an
implantation site comprising:
[0131] disposing an implantable medical device of any one of
statements 6-11 at an implantation site in an airway.
[0132] Statement 14. A method for making an implantable device
having a superhydrophobic surface comprising:
[0133] providing an airway stent having a first end, a second end,
and an inner surface defining a lumen extending from the first end
to the second end;
[0134] disposing on the airway stent a surface that is hydrophobic
and has dynamic water contact angles of 145 degrees or greater.
[0135] Statement 15. The method of claim 14 wherein disposing a
hydrophobic surface on the airway stent comprises:
[0136] disposing a polymer coating on at least the inner surface of
the airway stent and forming a hydrophobic microstructure on the
coating by one or more techniques selected from the group
consisting of laser ablation, photolithography-based
microfabrication, solidification of melted alkylketene dimer,
microwave plasma enhanced chemical vapor deposition of
trimethoxylmethoxysilane, phase separation, and domain selective
oxygen plasma treatment; or
[0137] roughening an outer surface of a mandrel, placing an airway
stent on the mandrel, applying a polymeric material to the airway
stent and mandrel, and curing the polymeric material to form the
hydrophobic surface in the form of an airway stent coating.
[0138] Statement 16. An implantable medical device having a
surface, at least a portion of the surface being
superhydrophobic.
[0139] Statement 17. The implantable medical device of statement 16
wherein a portion of the surface has a micropattern which provides
enhanced adhesion to tissue as compared with other portions of the
surface.
[0140] Statement 18. The implantable device of any of statements
16-17 wherein the device is tubular.
[0141] Statement 19. The implantable device of statement 18 wherein
the device comprises a stent and the superhydrophobic surface is a
surface of the stent.
[0142] Statement 20. The implantable device of statement 19 wherein
the superhydrophobic surface is in the form of a polymeric
coating.
[0143] Statement 21. The implantable device of statement 19 wherein
the stent is made of a polymer.
[0144] Statement 22. The implantable device of any of statements
16-21 wherein the superhydrophobic surface is in an inner surface
of the device and defines a lumen extending through the device.
[0145] Statement 23. The implantable device of any of statements
17-22 wherein the portion of the surface having a micropattern
which provides enhanced adhesion is located at one end of the
device.
[0146] Statement 24. The implantable device of any of statements
17-23 wherein the portion of the surface having a micropattern
which provides enhanced adhesion is located at both ends of the
device.
[0147] Statement 25. The implantable device of any of statements
17-24 in the form of an airway stent.
[0148] Statement 26. The implantable device of any of statements
17-24 in the form of an esophageal stent.
[0149] Statement 27. The implantable device of any of statements
17-26 wherein the superhydrophobic surface extends over the
entirety of the inner surface of the device.
[0150] Statement 28. The implantable device of any of statements
17-26 wherein the superhydrophobic surface extends over only one
end of the inner surface of the device.
[0151] Statement 29. The implantable device of any of statements
17-26 wherein the superhydrophobic surface extends over only a
first end and a second end of the inner surface of the device, the
remainder of the inner surface not having a superhydrophobic
surface.
[0152] Statement 30. The implantable device of any of statements
17-29 wherein an outer surface of the device is provided at one end
with a region having a micropattern which provides enhanced
adhesion.
[0153] Statement 31. The implantable device of any of statements
17-29 wherein an outer surface of the device is provided at both
ends with a region having a micropattern which provides enhanced
adhesion.
[0154] Statement 32. The implantable device of any of statements 31
wherein an outer surface of the device is with a superhydrophobic
region between the ends.
[0155] Statement 33. The implantable device of any of statements
17-24 and 27-33 in the form of a biliary stent.
[0156] Statement 34. The implantable device of any of statements
17-24 and 27-33 in the form of a pancreatic stent.
[0157] Statement 35. The implantable device of any of statements
17-34 wherein a portion of a surface of the device has a pattern of
microprotrusions which extend parallel to one another.
[0158] Statement 36. The implantable device of any of statements
17-24, 27-33 and 35 in the form of a hemostasis clip.
[0159] Statement 37. The implantable device of any of statements
17-36 where the superhydrophobic region is characterized as having
contact angles of at least 145 degrees.
[0160] The above disclosure is intended to be illustrative and not
exhaustive. This description will suggest many variations and
alternatives to a person of ordinary skill in this art. The various
elements shown in the individual figures and described above can be
combined or modified for combination as desired. All these
alternatives and variations are intended to be included within the
scope of the claims where the term "comprising" means "including,
but not limited to".
[0161] Further, the particular features presented in the dependent
claims can be combined with each other in other manners within the
scope of the present disclosure such that the present disclosure
should be recognized as also specifically directed to other
embodiments having any other possible combination of the features
of the dependent claims. For instance, for purposes of claim
publication, any dependent claim which follows should be taken as
alternatively written in a multiple dependent form from all prior
claims which possess all antecedents referenced in such dependent
claim if such multiple dependent format is an accepted format
within the jurisdiction (e.g., each claim depending directly from
claim 1 should be alternatively taken as depending from all
previous claims). In jurisdictions where multiple dependent claim
formats are restricted, the following dependent claims should each
be also taken as alternatively written in each singly dependent
claim format which creates a dependency from a prior
antecedent-possessing claim other than the specific claim listed in
such dependent claim below.
[0162] Those skilled in the art can recognize other equivalents to
the specific embodiments described herein which equivalents are
intended to be encompassed by the claims attached hereto.
* * * * *
References