U.S. patent application number 12/508951 was filed with the patent office on 2010-02-18 for single piece double wall dilation balloon catheter.
Invention is credited to David G. Burton.
Application Number | 20100042198 12/508951 |
Document ID | / |
Family ID | 41681799 |
Filed Date | 2010-02-18 |
United States Patent
Application |
20100042198 |
Kind Code |
A1 |
Burton; David G. |
February 18, 2010 |
SINGLE PIECE DOUBLE WALL DILATION BALLOON CATHETER
Abstract
The present invention relates to medical devices for dilating or
enlarging strictures or narrowed regions of body vessels.
Specifically, the present invention relates to a high pressure
dilation balloon catheter that includes an elongate shaft extending
between a proximal end and a distal end, the proximal end being
adapted for attachment to a source of inflation fluid, and a lumen
extending through the shaft adapted for the passage of the
inflation fluid; and a balloon disposed on the distal end of the
shaft and having a balloon body extending between a proximal end
and a distal end of the balloon. The balloon body includes a first
layer, a second layer disposed about at least a portion of the
first layer, a plurality of longitudinally extending rib members
disposed between the first and the second layers and configured to
form a plurality of sealed cavities between the first and the
second layers; and a balloon chamber within the first layer, the
balloon chamber being in a communication with the lumen of the
shaft for inflating and deflating the balloon.
Inventors: |
Burton; David G.;
(Bloomington, IN) |
Correspondence
Address: |
BRINKS HOFER GILSON & LIONE/CHICAGO/COOK
PO BOX 10395
CHICAGO
IL
60610
US
|
Family ID: |
41681799 |
Appl. No.: |
12/508951 |
Filed: |
July 24, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61089746 |
Aug 18, 2008 |
|
|
|
Current U.S.
Class: |
623/1.11 ;
604/103.08 |
Current CPC
Class: |
A61M 2025/1072 20130101;
A61M 2025/1088 20130101; A61M 25/1011 20130101; A61F 2/958
20130101; A61M 25/104 20130101; A61M 25/1029 20130101; A61M
2025/1075 20130101; A61M 2025/1013 20130101 |
Class at
Publication: |
623/1.11 ;
604/103.08 |
International
Class: |
A61M 25/10 20060101
A61M025/10; A61F 2/84 20060101 A61F002/84 |
Claims
1. A dilation balloon catheter comprising: an elongate shaft
extending between a proximal end and a distal end, the proximal end
being adapted for attachment to a source of inflation fluid, and a
lumen extending through the shaft adapted for the passage of the
inflation fluid; a balloon disposed on the distal end of the shaft
and having a balloon body extending between a proximal end and a
distal end of the balloon, the balloon body comprising: a first
layer, a second layer disposed about at least a portion of the
first layer, a plurality of longitudinally extending rib members
disposed between the first and the second layers and configured to
form a plurality of sealed cavities between the first and the
second layers, and a balloon chamber within the first layer, the
balloon chamber being in a communication with the lumen of the
shaft for inflating and deflating the balloon.
2. The dilation balloon catheter of claim 1, wherein the first
layer, the second layer and the rib members are formed from a
single piece of a substantially non-compliant non-porous
elastomeric material.
3. The dilation balloon catheter of claim 2, wherein the
substantially non-porous elastomeric material is selected from the
group consisting of Nylon (Nylon 12), polyether block amide
(PEBAX), PEBAX 4033, PEBAX 5533, PEBAX 6333, and poly(ethylene
terephthalate) (PET).
4. The dilation balloon catheter of claim 1, wherein the balloon
has a predetermined inflated diameter anywhere in the range of from
about 2 millimeters to about 30 millimeters.
5. The dilation balloon catheter of claim 1, wherein the first
layer has thickness from about 0.014 millimeters to about 0.060
millimeters.
6. The dilation balloon catheter of claim 1, wherein the second
layer has thickness from about 0.008 millimeters to about 0.047
millimeters.
7. The dilation balloon catheter of claim 1, wherein the proximal
and the distal ends of the balloon body are each tapered.
8. The dilation balloon catheter of claim 1, wherein the balloon
body comprises from 2 to 5 rib members circumferentially disposed
about the first layer of the balloon body.
9. The dilation balloon catheter of claim 1, wherein the rib
members longitudinally extend though the entire length of the
balloon body.
10. The dilation balloon catheter of claim 1, further comprising a
lubricant disposed in each of the cavities.
11. The dilation balloon catheter of claim 10, wherein the
lubricant is silicone.
12. The dilation balloon catheter of claim 1, wherein the first and
the second layers comprise different materials.
13. The dilation balloon catheter of claim 1, wherein the first and
the second layers comprise different thicknesses.
14. The dilation balloon catheter of claim 1, wherein the balloon
is configured to exert an outward pressure of from about 12
atmospheres to about 30 atmospheres when inflated.
15. The dilation balloon catheter of claim 1, wherein the shaft
further comprises a wireguide lumen extending through at least a
portion thereof.
16. The dilation balloon catheter of claim 15, wherein the
wireguide lumen is disposed adjacent to the lumen of the shaft.
17. The dilation balloon catheter of claim 16, wherein the
wireguide lumen extends through a substantial portion of the shaft
and terminates in a proximal port near the proximal end of the
shaft.
18. The dilation balloon catheter of claim 15, wherein the shaft
comprises a port through a side wall thereof in communication with
the wireguide lumen, the port being located proximal of the balloon
and a substantial distance from the proximal end of the shaft.
19. The dilation balloon catheter of claim 15, wherein the
wireguide lumen is coaxially disposed within the lumen of the
shaft.
20. The dilation balloon catheter of claim 1, wherein the rib
members have height from about 0.03 millimeters to about 0.50
millimeters.
21. The dilation balloon catheter of claim 1, wherein the rib
members have a substantially uniform cross-sectional profile.
22. The dilation balloon catheter of claim 1, wherein the rib
members have a non-uniform cross-sectional profile.
23. A method for dilating a vessel stricture comprising: providing
the dilation balloon catheter of claim 1; positioning the balloon
within or near the vessel stricture; and inflating the balloon to
dilate or widen the vessel stricture.
24. The method of claim 23, further comprising the steps of:
providing a stent; compressing the stent about the balloon when the
balloon is in an uninflated state; and expanding the balloon to
expand and deploy the stent.
Description
RELATED APPLICATIONS
[0001] The present patent document claims the benefit of the filing
date under 35 U.S.C. .sctn.119(e) of Provisional U.S. Patent
Application Ser. No. 61/089,746, filed Aug. 18, 2008, which is
hereby incorporated by reference.
BACKGROUND
[0002] A variety of body lumens are subject to undesired strictures
or narrow regions. For example, blood vessels can be blocked or
narrowed by atherosclerosis, while esophageal strictures can arise
from individual anatomical differences, or from diseases such as
connective tissue disorder.
[0003] Procedures for dilating or enlarging such strictures or
narrowed regions often entail the use of a balloon dilation
catheter. In general, such catheters include a deflated balloon
which can be positioned across a particular stricture or narrowed
region, and which is then inflated with an inflation fluid in order
to widen the lumen without trauma to the wall of the lumen.
[0004] Conventional dilation balloons fall into high, medium, and
low pressure ranges. Low pressure balloons are those that have
burst pressures below 6 atmospheres (ATM) (6.1.times.10.sup.5
Pascals). Medium pressure balloons are those that have burst
pressures between 6 and 15 ATM (6.1.times.10.sup.5 and
1.2.times.10.sup.6 Pa). High pressure balloons are those that have
burst pressures above 15 ATM (1.2.times.10.sup.6 Pa) and as high as
30 ATM. The term "burst pressure" refers to the maximum pressure
which can be slowly applied to the balloon (at a specific
temperature and for a specified amount of time (e.g., seconds or
minutes)) without causing it to rupture or burst. Burst pressure is
determined by such factors as the wall thickness and tensile
strength of the balloon material.
[0005] High pressure balloons are desirable because they have the
ability to exert more force and "crack" hard lesions. High pressure
balloons are useful in high pressure procedures, such as
Percutaneous Transluminal Angioplasty (PTA) in the peripheral
vasculature, including the iliac, femoral, ilio-femoral, popliteal
and renal arteries, and for the treatment of obstructive lesions of
native or synthetic arteriovenous dialysis fistulae. High pressure
balloons are also useful in stent deployment.
[0006] A biocompatible metal stents are often used to prop open
blocked coronary arteries and to keep them from re-closing after
balloon angioplasty. In an exemplary procedure, balloon of
appropriate size and pressure is first used to open the lesion. The
process is then repeated with a stent crimped onto a high pressure
balloon. The stent is deployed when the balloon is inflated. A
medium to high pressure balloon is preferable for stent deployment
because the stent must be forced against the artery's interior wall
so that it will fully expand, thereby precluding the ends of the
stent from projecting into the arterial channel, which may inhibit
flow there through and encourage the formation of thrombus.
[0007] High pressure balloon materials are typically stiffer than
conventional medium or low pressure balloon materials. Whereas
medium or low pressure balloons use materials such as polyethylene,
high pressure balloons use materials such as Nylon 12 or PET. See,
for example, U.S. Pat. No. 4,490,421, U.S. Pat. No. Re. 32,983,
U.S. Pat. No. Re. 33,561, and EP 0135990, which are incorporated
herein by reference in their entirety, which disclose a high
molecular weight, biaxially oriented, flexible, polymeric balloon
with a tensile strength of at least 31,714 psi (218.86 MPa), which
can be made of PET. See, also, U.S. Pat. No. 5,264,260, which
discloses a PET balloon, optionally melt blended or mixed with
other polymeric or nonpolymeric materials, having an intrinsic
viscosity of less than or equal to 0.6 dl/g and a calculated radial
tensile strength greater than about 25,000 psi (172 MPa), and is
also incorporated by reference in its entirety.
[0008] In general, improvements have been made to conventional high
pressure balloons over the years. However, because these balloons
are subject to the application of high pressure, these balloons are
still prone to puncture or tearing, such as circular tearing of the
balloons under burst pressure. Moreover, when these balloons burst
in a constricted state, they often tear along a circumferential
path that may lead to separation of the balloon into two or more
pieces. As a consequence, forceps or other device may need to be
inserted into a patient to remove the balloon pieces thus requiring
more complicated and/or longer procedures.
[0009] As such, there still exists a need in the industry for high
pressure balloons which display improved puncture and tearing
resistance, when compared to the conventional high pressure
balloons, while maintaining sufficient burst strength.
SUMMARY
[0010] In one embodiment, the invention relates to a dilation
balloon catheter. The dilation balloon catheter includes an
elongate shaft extending between a proximal end and a distal end,
the proximal end being adapted for attachment to a source of
inflation fluid, and a lumen extending through the shaft adapted
for the passage of the inflation fluid; and a balloon disposed on
the distal end of the shaft and having a balloon body extending
between a proximal end and a distal end of the balloon. The balloon
body includes a first layer, a second layer disposed about at least
a portion of the first layer, a plurality of longitudinally
extending rib members disposed between the first and the second
layers and configured to form a plurality of sealed cavities
between the first and the second layers, and a balloon chamber
within the first layer, the balloon chamber being in a
communication with the lumen of the shaft for inflating and
deflating the balloon. The first layer, the second layer and the
rib members may each be formed from a single piece of a non-porous
elastomeric material, such as Nylon (Nylon 12), polyether block
amide (PEBAX), PEBAX 4033, PEBAX 5533, PEBAX 6333, and
poly(ethylene terephthalate) (PET).
[0011] The balloon may have an inflated diameter anywhere in the
range of from about 2 millimeters to about 30 millimeters, and a
length anywhere in the range of from about 2 centimeters to about
25 centimeters. The first layer may have a thickness from about
0.014 m millimeters to about 0.060 millimeters. The second layer
may have a thickness from about 0.008 millimeters to about 0.047
millimeters. The proximal and the distal ends of the balloon body
may each be tapered. The balloon body may include from 2 to 5 rib
members circumferentially disposed about the first layer of the
balloon body. The rib members may longitudinally extend though the
entire length of the balloon body. The dilation balloon catheter
also may include a lubricant disposed in each of the cavities. The
lubricant may be silicone.
[0012] In certain embodiments, the first and the second layers may
comprise different materials. The first and the second layers may
also comprise different thicknesses. The balloon may be configured
to exert an outward pressure of from about 12 atmospheres to about
30 atmospheres when inflated.
[0013] The shaft of the dilation balloon catheter may further
include a wireguide lumen extending through at least a portion
thereof. The wireguide lumen may be disposed adjacent to the
inflation lumen of the shaft. The wireguide lumen may extend
through a substantial portion of the shaft and terminate in a
proximal port near the proximal end of the shaft. The shaft may
include a port through a side wall thereof in communication with
the wireguide lumen, the port being located proximal of the balloon
and a substantial distance from the proximal end of the shaft. The
shaft may include either one or both of these proximal ports. The
wireguide lumen may include a wire guide coaxially and moveably
disposed there through.
[0014] The rib members may have height from about 0.03 millimeters
to about 0.50 millimeters. The rib members may comprise various
cross-sectional profiles or shapes. For example, the rib members
may have a non-uniform width, such as the rib members include a
substantially larger width in the middle (bulging in the middle), a
substantially larger width towards the second layer, or tapered
width towards the first layer. Alternatively, the rib members may
have a uniform width, such as, a uniform width of a single
dimension.
[0015] In another embodiment, the invention relates to a method for
dilating a vessel stricture by providing a dilation balloon
catheter as described above; positioning the balloon within or near
the vessel stricture; and inflating the balloon to dilate or widen
the vessel stricture.
[0016] In yet another embodiment, the method may further include
the steps of providing a stent; compressing the stent about the
balloon when the balloon is in an uninflated state; and expanding
the balloon to expand and deploy the stent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The devices, systems and methods may be better understood
with reference to the following drawings and description. The
components in the figures are not necessarily to scale, emphasis
instead being placed upon illustrating the principles of the
invention. Moreover, in the figures, like referenced numerals
designate corresponding parts throughout the different views.
[0018] FIGS. 1A-1C depict exemplary dilation balloon catheter
device;
[0019] FIG. 2 depicts dilation balloon portion of the device of
FIGS. 1A-1C;
[0020] FIG. 3 shows cross-sectional view though E-E of the
exemplary dilation balloon of FIG. 2;
[0021] FIGS. 4A-4D depicts illustrative rib members; and
[0022] FIGS. 5A-5C depicts coaxial configuration of the shaft of an
exemplary dilation balloon catheter device;
[0023] FIG. 6 depicts exemplary inflation device;
[0024] FIG. 7 depicts an exemplary shape of the extruded balloon
material;
[0025] FIG. 8 depicts an exemplary dilation balloon catheter device
deployed in a body lumen; and
[0026] FIG. 9 depicts yet another embodiment of the exemplary
dilation balloon catheter deployed in a body lumen.
DETAILED DESCRIPTION OF THE DRAWINGS AND THE PRESENTLY PREFERRED
EMBODIMENTS
[0027] The present invention relates to medical devices, and more
specifically to dilation catheter devices, which can be used for
dilation (i.e., mechanical widening) of strictures, during high
pressure procedures, such as Percutaneous Transluminal Angioplasty
(PTA) in the peripheral vasculature, including the iliac, femoral,
ilio-femoral, popliteal and renal arteries, and for the treatment
of obstructive lesions of native or synthetic arteriovenous
dialysis fistulae. The device of the present invention can also be
used for post-dilation of balloon expandable and self-expanding
stents in the peripheral vasculature and other bodily lumens of a
mammalian patient.
[0028] Embodiments of the dilation catheter devices described
herein generally include a shaft adapted for the passage of the
inflation fluid there though and a balloon disposed on the distal
end of the shaft. The balloon has a balloon body that includes two
separate layers (inner and outer balloon walls) and a plurality of
longitudinally extending rib members disposed between the two
layers and configured to form a plurality of sealed cavities
between the layers.
[0029] It is believed that the inclusion of rib members within the
double-walled balloon portion (i.e., balloon body) of the dilation
balloon catheter device provides a balloon catheter suitable for
use in high pressure applications. This is because the ribs will
tend to direct any tearing along longitudinal pathway and because
the rib members advantageously allow the two layers of the balloon
body to expand independently of each other during inflation of the
balloon, while maintaining contact with each other. Because the
layers are in contact with each other during inflation but moving
independently, the overall burst will be significantly higher than
a single layer balloon having dimensions (e.g., thickness)
equivalent to the dimensions of the two layers of the balloon body
combined. In addition, the rib members function to resist circular
tearing of the balloon under burst pressure.
[0030] Definitions:
[0031] Unless otherwise indicated, all ordinary words and terms
used herein shall take their customary meaning as defined in The
New Shorter Oxford English Dictionary, 1993 edition. All technical
terms shall take on their customary meaning as established by the
appropriate technical discipline utilized by those normally skilled
in that particular art area. All medical terms shall take their
meaning as defined by Stedman's Medical Dictionary, 27.sup.th
edition.
[0032] The terms "about" or "substantially" used with reference to
a quantity includes variations in the recited quantity that are
equivalent to the quantity recited, such as an amount that is
insubstantially different from a recited quantity for an intended
purpose or function.
[0033] The terms "adapted for" or "configured to" while referring
to an element of the dilation balloon catheter described herein
mean that the element is changed, modified, or specifically
designed so that it is suitable to perform a specified or desired
function.
[0034] As used herein, "disposed" means placed or arranged in a
particular order to define the relationship between elements or
components of a device. The term "disposed" can include, without
being limited to, terms, such as, placed, arranged, distributed, or
incorporated.
[0035] The term "non-compliant" refers to a type of material that
is used to form the balloon portion of the balloon catheter
described herein. "Non-compliant" material may be characterized by
high stiffness, rigidity, low compliance, and/or low elasticity.
The term "non-compliant," throughout the instant specification,
also refers to a material, which are substantially non-compliant
(i.e., semi-compliant) or substantially non-elastic. These terms
may be used interchangeably.
[0036] The term "proximal" refers to an area nearer to a point of
reference such as an origin or a point of attachment. In this
application the term proximal refers to an area nearer to the
physician.
[0037] The term "distal" refers to an area further from a point of
reference, e.g., further from a physician.
[0038] The term "shaft" refers to a tubular structure, such as, for
example, a catheter.
[0039] The term "tubular" refers to the general shape of a device
or an element of the device, which allows the device to carry fluid
along a distance or fit within a tubular structure such as an
artery.
[0040] The term "stent" refers to any device or structure that adds
rigidity, expansion force or support to a tubular structure, such
as vessel wall.
[0041] The term "stent graft" refers to a type of endoluminal
prosthesis made of a tubular graft material and supported by at
least one stent.
[0042] Referring to FIGS. 1A-1C, an exemplary embodiment of the
present invention is shown and illustrates a high pressure dilation
balloon catheter 10, which includes an elongate shaft 20 and a
balloon 30 disposed on a distal end 50 of the shaft 20. As shown in
the drawings, the balloon 30 comprises in its fully inflated
profile shape, a cylindrical working portion with an inflated
diameter located between a pair of conical end portions, and
proximal and distal legs (sometimes referred to as neck portions)
extending from the conical portions and affixed to the shaft. The
balloon in its deflated profile shape may have several pleats (not
shown) that allow the balloon to be wrapped around the shaft to
reduce its profile so as to facilitate advancement of the balloon
catheter into the patient.
[0043] Specifically, the balloon catheter 10 includes an elongate
shaft (i.e., tube) 20, which can be made from a flexible catheter
tubing, such as Nylon. The shaft 20 is preferably tubular and
extends between a proximal end 40 and a distal end 50, where the
proximal end 40 can attach to a hub 60, which can include an
inflation port 70, which then connects to a source of inflation
fluid, i.e., inflation device (not shown). An exemplary inflation
device, such as a syringe 600, is illustrated in FIG. 6.
[0044] As shown in FIG. 1A, the balloon catheter may be also
adapted for use with optional ancillary instrumentation, such as a
wire guide 90, where the hub 60 also includes a wireguide port 80
in communication with a wire guide lumen 110.
[0045] In a first illustrative embodiment, the wire-guided dilation
balloon catheter 10 includes a shaft 20 that comprises a dual lumen
shaft, best seen in FIG. 1B, which is a cross-section though B-B in
FIG. 1A. In particular, the shaft 20 includes an inflation lumen
100 for the passage of the inflation fluid, and a wireguide lumen
110 to accommodate wire guide 90 that may be used in a procedure.
The inflation lumen 100 terminates at the location near the
proximal balloon bond 120 and is in fluid communication with the
interior of the balloon for the delivery of the inflation fluid
into the balloon 30. A single lumen shaft 130 extends from the main
shaft 20 and through the balloon body 140 (FIGS. 1A and 1C) and is
in communication with the wireguide lumen 110 of the shaft 20. FIG.
1C is a cross-section taken along line C-C of FIG. 1A. The shaft
130 terminates near the distal end 180 of the balloon 30 and can
include a passageway via which the wire guide 90 may enter and exit
the balloon catheter 10 to aid in cannulation or perform some other
function. The inflation fluid, such as water or saline, for
inflation of the balloon 30 is supplied via the main shaft 20
through the inflation lumen 100 and into the balloon chamber 150.
The single lumen shaft 130 may be heat bonded to the distal end 160
of the shaft 20 or may be formed as a unitary structure.
[0046] As mentioned above, the dilation balloon catheter 10 of this
invention includes a balloon 30 disposed on a distal end 50 of the
shaft 20. The illustrative balloon 30 of the balloon catheter 10 is
shown in greater detail in FIGS. 2 and 3. The balloon 30 has a
balloon body 140 extending between a proximal end 170 and a distal
end 180 of the balloon 30. The balloon body 140 includes a first
layer (i.e., inner wall) 190 and a second layer (i.e., outer wall)
200 which is disposed about at least a portion of the first layer
190. The balloon body 140 also includes a plurality of
longitudinally extending rib members 210 disposed between the first
and the second layers 190, 200, and a balloon chamber 150 within
the first layer 190. The balloon chamber 150 remains in
communication with the inflation lumen 100 of the shaft 20 for
inflating and deflating the balloon 30. As illustrated in FIG. 3,
which is a cross-section though E-E of FIG. 2, the rib members 210
can form a plurality of sealed cavities 220 between the first 190
and the second 200 layers of the balloon 30.
[0047] Each of the layers 190, 200 making up the balloon 30 can be
formed to have a specific inflated diameter. Preferably, the
inflated diameter of the inner layer is slightly smaller than the
inflated diameter of the outer layer.
[0048] The balloon portion 30 of the dilation balloon catheter 10
can be formed of a balloon material that is preferably
substantially non-compliant and non-porous, and stretches a
relatively small amount under pressures of 15 atmospheres or more.
Various materials may be used, including Nylon (e.g., Nylon 12),
polymeric materials such as poly(ethylene terephthalate) (PET),
PEEK, PEBAX material, or a block copolymer thereof. Other suitable
materials may also be used.
[0049] The balloon 30 can preferably be formed from a single piece
of suitable balloon material by a well-known means, such as blow
molding, whereby a length of PET tubing, sufficient in length to
form the final desired length of the balloon, is placed and clamped
within a mold conforming to the final shape of the fully distended
balloon. Hot air is passed through the tubing, causing the tubing
to expand against the contours of the mold. The tubing and molding
process parameters necessary to achieve the desired balloon are
determined by the required burst strength and recommended pressure
of the balloon, the material used, and the size of the balloon. One
source of the balloon portion of the illustrative embodiment is
Advanced Polymers, Inc. (Salem, N.H.).
[0050] The balloon 30 can be attached to the shaft 20 by variety of
methods, including by inserting the distal end 50 of the shaft 20
into the proximal opening 230 of the balloon 30 and bonding thereto
using a well-known method, such as for example an
ultraviolet-curable adhesive. Alternatively, the balloon 30 may be
attached to the shaft 20 with the use of a solvent or by gluing.
Other suitable methods of attachment are also contemplated.
[0051] Referring back to FIG. 2, the distal end 180 of the balloon
30 may have a standard tapered or domed configuration with a
flexible tip 240. Alternatively, the distal end 180 of the balloon
30 may be formed so that it is generally truncate in shape, having
a substantially flat end, rather than comprising standard
configurations discussed above.
[0052] The balloon 30 is configured to be inflated to a
predetermined or specific "inflated balloon diameter" or "outer
balloon diameter." The terms "inflated balloon diameter" or "outer
balloon diameter" of the balloon 30 refer to the diameter of the
outer most layer of the second layer and are specific or
predetermined for a given balloon. Preferably, the inflated balloon
diameter can fall within a range from about 2 millimeters to about
30 millimeters depending on the application of the balloon catheter
and/or the medical procedure. More preferably, the inflated balloon
diameter can fall within a range from about 3 millimeters to about
14 millimeters.
[0053] Also, although the above described balloon 30 may be
configured to be inflated to a single predetermined or specific
balloon diameter, due to variations in pressure, materials,
environmental and other factors, the inflated balloon diameter may
be slightly larger or slightly smaller than the single
predetermined or specific diameter of the balloon 30. For example,
for a balloon configured to have the single predetermined or
specific inflated balloon diameter of 10 millimeters, the balloon
is configured to be inflated to an inflated balloon diameter in the
range from about 9.8 millimeters to about 10.2 millimeters.
[0054] Moreover, although, in the embodiments of the device
described above, the balloon 30 can have a single predetermined
inflated balloon diameter, the balloon 30 can be configured to be
inflated to a plurality of predetermined or specific balloon
diameters, each inflated balloon diameter being the result the
pressure or the amount of inflation fluid delivered to the balloon
30.
[0055] The length of the balloon body 140 can be in a range of from
about 2 centimeters to about 25 centimeters; preferably the length
of the balloon body 140 can be in the range from about 2
centimeters to 14 centimeters.
[0056] The balloon will preferably have a burst pressure of at
least 12 ATM; and more preferably at least 20 ATM; and most
preferably as high as 30 ATM.
[0057] Referring to FIG. 3, which is a cross-sectional view though
E-E of the balloon catheter shown in FIG. 2, the balloon body 140
of the balloon catheter 10 includes a first layer 190 and a second
layer 200, which is disposed about at least a portion of the first
layer 190. The two layers 190, 200 are preferably made from a
single piece of a non-porous balloon material as described above
with reference to the material that may be used to form the balloon
30.
[0058] The thickness of the first (i.e., inner) layer 190 of the
balloon 30 may be in a range of from about 0.014 millimeters to
about 0.060 millimeters; and preferably in a range of from about
0.020 millimeters to about 0.045 millimeters. The thickness of the
second (i.e., outer) layer 200 of the balloon 30 may be in a range
of from 0.008 millimeters to about 0.047 millimeters; and
preferably, in a range of from about 0.012 millimeters to about
0.035 millimeters.
[0059] The combined thickness of the two layers 190, 200 of the
balloon body 140 will depend on the balloon size and application
for which the balloon is intended. Nonetheless, it is preferred
that the first layer 190 is thicker that the second layer 200 of
the balloon body 140. The combined thickness of the balloon body
layers 190, 200 may be in a range of from about 0.032 millimeters
to about 0.08 millimeters (not taking into account the thickness of
the cavity 220 between the two layers 190, 200, as discussed
below). Preferably, the combined thickness of the balloon body
layers 190, 200 may be in a range of from about 0.032 millimeters
to about 0.07 millimeters; more preferably the combined thickness
of the balloon body layers 190, 200 may be in a range of from about
0.032 millimeters to about 0.06 millimeters; and most preferably
the combined thickness of the balloon body layers 190, 200 may be
in a range of from about 0.032 millimeters to about 0.05
millimeters.
[0060] The balloon 30 also includes a balloon chamber 150 within
the first layer 190 of the balloon body 140. The balloon chamber
150 is in communication with the lumen 100 of the shaft 20 for
inflating and deflating the balloon 30.
[0061] Also, the balloon 30 includes a plurality of longitudinally
extending rib members 210 disposed between the outer surface of the
first layer 190 and the inner surface of the second layer 200 of
the balloon body 140, as shown in FIGS. 2 and 3. Preferably, the
rib members 210 extend though the entire length of the balloon body
140 and are circumferentially disposed about the first layer 190 of
the balloon body 140. The rib members 210 are preferably made from
the same material as the two layers 190, 200 of the balloon body
and preferably from a single piece of balloon material. Some
exemplary materials that may be used to form the first and the
second layers 190, 200 of the balloon body 140 were provided above.
Preferably, the rib members are integral with the two layers of the
balloon body and connect the two layers of the balloon body, as
illustrated in FIG. 3.
[0062] The rib members 210 can vary in number, shape and size. In
certain instances, the balloon 30 can include at least two rib
members 210. In certain other embodiments, the balloon 30 can
include at least three rib members 210. In certain other instances,
the balloon 30 can include at least four rib members 210. In yet
further instances, the balloon 30 can include at least five rib
members 210. The number of the rib members 210 can range from 2 to
5.
[0063] As illustrated in FIGS. 4A-4D, the rib members 210 can have
various cross-sectional profiles or shapes. In cross section, the
rib members may have a non-uniform or a substantially uniform
configurations or profiles. For example, the rib members may have a
substantially larger portion in the middle of the rib member (i.e.,
bulging in the middle, FIG. 4A); a substantially larger portion
towards the second layer (i.e., outer wall) 200 (FIG. 4B); or a
tapered profile though the first layer (i.e., inner wall) 190 (FIG.
4C). In other instances, the rib members may have a substantially
uniform cross-sectional profile having a single dimension, as
illustrated in FIG. 4D. Other cross-section profiles of the rib
members 210 are also contemplated and may be suitable for use with
the balloon catheter.
[0064] Concerning the size of rib members, the rib members may have
height and width from about 0.03 millimeters to about 0.50
millimeters. Preferably, the height and width can range from about
0.05 millimeters to 0.40 millimeters.
[0065] Referring back to FIG. 3, the rib members 210 form a
plurality of sealed cavities 220 between the first and the second
layers 190, 200. The thickness of the cavities 220 may vary
depending on the desired overall thickness of the balloon 30,
thickness of the two layers 190, 200 that form the balloon body
140, and application. Other factors may also play a role.
Specifically, the size of the rib members may play the key role for
this, in that the cavity thickness will never be greater than the
pre-molded rib height. Additionally, the thickness of the cavities
may further depend on the blow molding method selected to form the
balloon. The desired cavity thickness is preferably the same as the
preferred rib heights (0.03 millimeters to 0.5 millimeters)
[0066] By including the rib members 210 within the double-walled
balloon portion 30 of the dilation balloon catheter device 10, the
balloon catheter 10 can be used for high pressure applications. The
rib members 210 function to resist any tearing along the
longitudinal pathway. The rib members 210 advantageously allow the
two layers 190, 200 of the balloon body 140 to expand independently
of each other during inflation of the balloon 30, while maintaining
contact with each other. Because the layers 190, 200 are in contact
with each other during inflation but moving independently, as
discussed previously, the overall burst will be significantly
higher than a single layer balloon having dimensions (e.g.,
thickness) equivalent to the dimensions of the two layers of the
balloon body combined.
[0067] In addition, the rib members 210 function to resist circular
tearing of the balloon under burst pressure.
[0068] In the embodiments heretofore described, a lubricant can be
installed into the cavities 220 formed by the rib members.
Preferably, the lubricant is installed into the cavities prior to
blow molding. The lubricant in the cavities may enhance independent
wall movements of the two layers of the balloon. Some exemplary
lubricants include, for example, silicone and glycerol. Other
lubricants may also be used and are also contemplated.
[0069] In one alternative embodiment illustrated in FIGS. 5A-C, the
shaft 510 can have a coaxial configuration, where wire-guided
dilation balloon catheter 500 includes an inner shaft 520 coaxially
disposed within the main shaft 510 to which the balloon portion 530
is attached. Cross-sectional views though B-B and C-C of the
balloon catheter of FIG. 5A are shown in FIGS. 5B and 5C,
respectively. The inner shaft 520 serves as the conduit for the
wire guide 540, which in one embodiment, is a standard 0.035'' wire
guide that is loaded into, and is extendable from the inner shaft
lumen 550. In the illustrative embodiment, both the inner and main
shafts 520, 510 can be made of poly-ether ether ketone (PEEK). In
other embodiments, a metal hypotube may be employed for all or at
least the proximal portion 560 of the shaft 510. The inner and
outer shafts 520, 510 are sized to allow the flow of inflation
fluid within the annular space 570 between the two shafts 510, 520
and into the balloon chamber 580 of the balloon 530 to expand the
balloon 530.
[0070] The inner shaft 520 can terminate within the distal end 590
of the balloon 530 or a few millimeters distally thereof. The wire
guide 540 is typically utilized for adding stiffness or pushability
to the balloon catheter 500, or it may be introduced separately
into the patient and then used to guide the balloon catheter into
the patient. The inner shaft 520 alone may provide sufficient
stiffness and pushability for some applications. If desired, a wire
guide 540 may at some point be replaced with a different wire guide
having characteristics more desirable for a particular procedure.
In the illustrative embodiment, the inner shaft 520 comprises a
port 400 through a side wall thereof in communication with the
wireguide lumen 550, the port being located proximal of the balloon
530 and a substantial distance from the proximal end 560 of the
shaft 510. A standard hub 300 provides a port 310 for the infusion
of a balloon inflation fluid, such as water or saline.
[0071] Alternatively, the outer and inner shafts may be fixed
relative to one another longitudinally by a standard hub, which
provides access for the wire guide, and a port for the infusion of
a balloon inflation fluid, as described above in connection with a
dual lumen shaft.
Method of Making the Device
[0072] Various methods may be utilized to form the balloon catheter
described herein. One exemplary method of making multi-layered
balloons is described in PCT Pub. No. WO 07/75585A2 and U.S. Pub.
No. 2007/0167973A1, the entire contents of which are hereby
incorporated by reference. Additionally, U.S. Provisional Pat.
Application Ser. No. 61/036,176 filed Mar. 13, 2008 describes a
process of making a balloon that may be suitable to form the inner
and the outer layers of the balloon of the balloon catheter
described herein.
[0073] Specifically, the balloon can be made according to the
following process. The balloon material is first extruded into a
suitable shape, as seen for example in FIG. 7. The extruded balloon
material is then placed into a forming mold to blow mold the
balloon portion of the balloon catheter. Heat (above T.sub.g but
below the melting temperature for the material) and low pressure
(2-5 ATM) is applied. The cavities 220 are blocked, closed off or
plugged prior to the balloon forming process/pressurization
process. Only the inner lumen of the raw balloon material is
pressurized (the cavities are not under pressure, as this would
cause them to blow out). Next, the balloon material is stretched
longitudinally, which will decrease the overall dimensions (or
cross sectional area) of the balloon material, and give it the
necessary longitudinal strength. Next, high pressure is applied to
the mold to radially expand the balloon into the shape of the mold.
This gives the balloon the necessary radial strength and shape. The
ribs 210 prevent expansion of the second balloon layer 200, and
thereby leaving a one-piece balloon with ribs. The ribs 210 run the
entire length of the balloon, including the tapers (not shown in
this figure).
[0074] In an exemplary method of using the balloon catheter device
of the present invention, to dilate a stricture, a small incision
is made in the patient to facilitate the insertion of a long, thin
introducer sheath. A guide catheter is then passed through the
sheath and into the narrowed artery. The physician may monitor the
insertion of the guide catheter under fluoroscopy. An injection
through the guide catheter of contrast dye/medium allows the
physician visualization of the peripheral arteries.
[0075] Once the guide catheter is engaged in the ostium of the
artery where the lesion/vessel stricture is located, a wire guide
is threaded through the guide catheter. The wire guide is then
advanced under fluoroscopy beyond the lesion to a distal location
within the artery. With the wire guide in place, the dilation
balloon catheter of the present invention is inserted over the wire
guide and advanced to the lesion site, as illustrated in FIGS. 8
and 9.
[0076] Referring to FIG. 8, once the balloon catheter 10 comprising
a shaft 20 and a balloon 30, and optionally a wireguide 90, has
been properly positioned in the bodily lumen 11, the balloon 30 is
dilated within the artery at the lesion/stricture site 12, causing
a compression of the arterial plaque against the inner lining of
the arterial wall. Subsequent balloon dilation may be used if the
physician decides to increase the atmospheres of pressure or
duration of time that the balloon is applied to the lesion.
[0077] Referring to FIG. 9, in addition or alternatively, the
exemplary device of this invention may be used to expand and deploy
a stent 800. Specifically, upon examination of the pre and post PTA
images, the physician may decide to follow the PTA procedure with
the implantation of a stent 800 at the site of the lesion. A stent
800 may be provided, which can then be compressed about the balloon
30 when the balloon is in an uninflated state. Once in position,
the balloon can be expanded to expand and deploy the stent.
[0078] The physician may also consider using an adjunctive imaging
device such as intravascular ultrasound (IVUS). This provides the
physician with a cross-sectional and longitudinal image of the
vessel and morphology of the plaque. IVUS allows for measurement of
the artery and the plaque burden, which assists the physician with
accurate sizing of the stent to be used.
[0079] It will be appreciated that the devices described herein
will be useful in catheters, particularly high-pressure vascular
balloon catheters, other types of medical procedures and in various
types of balloons, wherein they will provide structural strength to
resist bursting under pressure, torsional and longitudinal
directivity and kink resistance while maintaining the small
diametric profile necessary for traversing small tortuous vascular
channels.
[0080] All patents, patent applications, provisional applications,
and publications referred to or cited herein are incorporated by
reference in their entirety, including all figures and tables, to
the extent they are not inconsistent with the explicit teachings of
this specification.
[0081] While various embodiments of the invention have been
described, it will be apparent to those of ordinary skill in the
art that many more embodiments and implementations are possible
within the scope of the invention. Accordingly, the invention is
not to be restricted except in light of the attached claims and
their equivalents.
* * * * *