Note: Descriptions are shown in the official language in which they were submitted.
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CORRUGATED BALLOON CATHETER AND METHODS OF USE THEREOF
FIELD OF THE INVENTION
This invention relates in general to the fields of medical balloon catheters
and more
particularly to systems and catheters having inflatable intussusceptible
corrugated
balloons and methods of their manufacturing and use.
CROSS-REFERENCE TO RELATED US APPLICATIONS
This application claims priority from and the benefit of US Provisional Patent
Application Serial Number 61/077,520 filed on July, 02, 2008 and entitled
"CORRUGATED BALLOON CATHETERAND METHODS OF USE THEREOF"
and US Provisional Patent Application Serial Number 61/143,847 filed on
January, 12,
2009 and entitled "BALLOON AND CATHETER SYSTEM AND METHODS FOR
MAKING SAME" both of which are incorporated herein by reference in their
entirety.
BACKGROUND OF THE INVENTION
Catheters are used in various interventional procedures for delivering
therapeutic
means to a treated site (e.g., body organ or passageway such as blood
vessels). In many
cases, a catheter with a small distal inflatable balloon is guided to the
treated site. Once
the balloon is in place it is inflated by the operator for affixing it in
place, for expanding
a blocked vessel, for placing treatment means (e.g., stent) and/or for
delivering surgical
tools (e.g. knives, drills etc.) to a desired site. In addition, catheter
systems have also
been designed and used for retrieval of objects such as stents from body
passageways.
Two basic types of catheter have been developed for intravascular use: over-
the-wire
(OTW) catheters and rapid-exchange catheters.
OTW catheter systems are characterized by the presence of a full-length guide
wire,
such that when the catheter is in its in situ working position, said guide
wire passes
through the entire length of a lumen formed in, or externally attached to, the
catheter.
OTW systems have several operational advantages which are related to the use
of a full
length guide wire, including good stiffness and pushability, features which
are important
when maneuvering balloon catheters along tortuous and/or partially occluded
blood
vessels.
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U.S. Pat. No. 6,039,721 to Johnson et al. describes a balloon catheter system
comprising
two concentrically-arranged conduits, with a balloon connected between the
distal
regions thereof. The catheter system permits both expansion/deflation of the
balloon and
alteration in the length of the balloon when in situ, such that the balloon
may be moved
between extended and intussuscepted conformations. The catheter system is
constructed
in order that it may be use for two main purposes: firstly, treatment (i.e.
expansion) of
different-length stenosed portions of blood vessels with a single balloon and
secondly,
the delivery of either stents or medication to intravascular lesions, wherein
the stent or
medication is contained within the distally-intussuscepted portion of the
balloon. When
used for multiple, differing-length lesion expansion, the balloon is inserted
into blood
vessel in a collapsed, shortened, intussuscepted conformation, and is advanced
until it
conies to rest in the region of the shortest lesion to be treated. The balloon
is then
inflated and the lesion treated (i.e. expanded). Following deflation of the
balloon, the
distal end of the catheter system is moved such that the balloon becomes
positioned in
the region of the next--shortest lesion to be treated. The effective length of
the balloon is
then increased by moving the inner conduit in relation to the proximal
conduit, following
which the balloon is again inflated and the lesion treated. In this way, a
series of
different length stenoses, in order from the shortest to the longest, may be
treated using a
single balloon. When used for stent delivery, the stent is pre-loaded into a
proximal
annular space formed as a result of balloon intussusception. The balloon is
then moved
to the desired site and the stent delivered by means of moving the inner
conduit distally
(in relation to the outer tube), thereby "unpeeling" the stent from the
catheter.
WO 2000/38776 discloses a dual-conduit balloon catheter system similar in
basic
design to that described above in relation to U.S. Pat. No. 6,039,721. This
catheter
system is intended for use in a vibratory mode in order to break through total
occlusions
of the vascular lumen. In order to fulfill this aim, the outer conduit has a
variable
stiffness along its length, while the inner conduit. In addition, the inner
conduit while
being intrinsically relatively flexible is stiffened by the presence of axial
tensioning
wires. These conduit design features are used in order to permit optimal
translation of
vibratory movements of the proximal end of the inner conduit into
corresponding
vibration of the distal tip thereof.
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Rapid exchange ("monorail") catheters typically comprise a relatively short
guide
wire lumen provided in a distal section thereof, and a proximal guide wire
exit port
located between the catheter's distal and proximal ends. This arrangement
allows
exchange of the catheter over a relatively short guide wire, in a manner which
is simple
to perform and which can be carried out by a single operator. Rapid exchange
catheters
have been extensively described in the art, for example, U.S. Pat. Nos.
4,762,129,
4,748,982 and EP0380873.
Rapid exchange catheters are commonly used in Percutaneous Transluminal
Coronary Angioplasty (PTCA) procedures, in which obstructed blood vessels are
typically dilated by a distal balloon mounted on the catheter's distal end. A
stent is often
placed at the vessel's dilation zone to prevent reoccurrences of obstruction
therein. The
dilation balloon is typically inflated via an inflation lumen which extends
longitudinally
inside the catheter's shaft between the dilation balloon and the catheter's
proximal end.
The guide wire lumen passes within a smaller section of the catheter's shaft
length
and it is accessed via a lateral port situated on the catheter's shaft. This
arrangement,
wherein the guidewire tube is affixed to the catheter's shaft at the location
of its lateral
port, usually prevents designers from developing new rapid exchange catheter
implementations which requires manipulating its inner shaft. For example,
extending or
shortening the catheter's length during procedures may be advantageously
exploited by
physicians to distally extend the length of the catheter into a new site after
or during its
placement in the patient's artery, for example in order to assist with the
passage of
tortuous vessels or small diameter stenoses, or to allow in-situ manipulation
of an
inflated balloon at the distal end of the catheter.
Published International Patent Application, Publication No. WO 2005/102184
discloses a catheter having a rollable expandable element. Published
International Patent
applications, Publication Nos. WO 2007/004221, WO 2007/042935 , WO 2008/004238
and WO 2008/004239, all five published international applications are
incorporated
herein by reference in their entirety for all purposes, disclose various types
of catheters
and catheter systems having intussuscepting balloon-like inflatable members
which may
be used, inter alia, to treat plaque by balloon inflation while efficiently
and safely
collecting plaque debris and other particulate matter from the lumen of
pathologically-
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involved blood vessels and to remove such particles and particulate matter
from the
blood vessel.
A problem frequently encountered in the use of inflatable balloons to treat
atheromatous plaque in blood vessels is that inflation of the balloon against
the wall of
the blood vessel may cause some damage to the blood vessel wall in the region
of
contact between the balloon and the blood vessel walls. Physicians are
therefore usually
reluctant to use balloons longer that the length necessary for treating most
of the plaque.
However, when the intussuscepting balloons as disclosed, inter alia, in WO
2005/102184 and WO 2007/004221 are used for treating plaque (by expanding the
balloon placed inside the plaque region or by other methods) and for trapping
and
internalizing debris particles or secretions and fluids from inside a treated
blood vessel,
one would like to increase the capacity of the balloon to trap and include
debris particles
in it's intussuscepted (invaginated) state without increasing the length of
the balloon
above the length that is recommended by the physician for the purpose of safe
plaque
treatment.
Another problem which may be encountered in the use of intussuscepting
balloons,
such as, for example, the balloons disclosed in WO 2005/102184 and WO
2007/004221
is that it is important to ensure that the distal end of the balloon (the end
attached to the
inner tube of the catheter) collapses preferentially at a lower pulling force
than the force
required to collapse the proximal end of the balloon (the end of the balloon
attached to
the outer tube of the catheter) to ensure proper intussuscepting of the
balloon. (The
proximal and distal ends of the balloon are defined as described in WO
2005/102184 and
WO 2007/004221).
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SUMMARY OF THE INVENTION
There is therefore provided a balloon catheter, the catheter includes an outer
conduit and an inner conduit, suitable for passage over a guide wire. The
inner conduit is
disposed within the lumen of the outer conduit such that the longitudinal axes
of the
inner and outer conduits are substantially parallel. The inner and outer
conduit are
positioned such that the distal tip of the inner conduit extends beyond the
distal tip of the
outer conduit. The inner conduit is capable of being moved along its
longitudinal axis in
relation to the outer conduit. The catheter also includes an inflatable
balloon having a
proximal margin attached to the outer surface of the distal tip of the outer
conduit and a
distal margin attached to the outer surface of the portion of the inner
conduit that extends
beyond the distal tip of the outer conduit. The inflatable balloon has at
least one
corrugated portion. The distal end portion of the balloon is capable of
intussuscepting
upon proximal movement of the inner conduit in relation to the outer conduit.
The
catheter also includes a fluid port for introducing an inflation fluid into
the space formed
between the inner surface of the outer conduit and the outer surface of the
inner conduit
and into the lumen of the balloon, and for removing the inflation fluid from
the space
and from the lumen.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the balloon catheter also includes a pressure
adjusting
mechanism for preventing substantial pressure changes within the space formed
between
the inner surface of the outer conduit and the outer surface of the inner
conduit and
within the lumen of the balloon upon axial movement of the inner conduit in
relation to
the outer conduit.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the pressure adjusting mechanism is selected from,
a pressure adjusting mechanism including a syringe-like structure disposed at
the
proximal end of the balloon catheter, the syringe-like structure includes a
barrel and a
plunger disposed within said barrel. The plunger co-axially surrounds the
proximal end
of the inner conduit, and is affixed thereto,
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an over-pressure outlet in fluidic communication with the lumen of the
inflatable
balloon and having an opening and a compliant member sealingly attached to the
opening for at least partially relieving over-pressure in the lumen,
an over-pressure valve outlet in fluidic communication with the lumen of the
inflatable balloon and an over-pressure valve disposed within the over-
pressure outlet to
allow discharging of fluid from the lumen when over-pressure conditions
develop in the
lumen, and
an expandable or inflatable portion of the outer conduit, capable of being
inflated
when over-pressure conditions occur in the lumen of the balloon to at least
partially
relieve the over-pressure in said lumen.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the inflatable balloon includes a substantially
cylindrical middle
portion flanked by a distally extending portion and a proximally extending
portion,
wherein the diameter of the distally extending portion diminishes in the
distal direction
and the diameter of the proximally extending portion diminishes in the
proximal
direction.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the balloon is selected from a balloon wherein at
least part of the
middle portion is corrugated, a balloon wherein at least part of the distal
portion is
corrugated, and a balloon wherein at least part of the middle portion and at
least part of
the distal portion is corrugated.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, at least part of the distal portion of the balloon is
corrugated such
that the force required for causing collapse of the distal portion of the
balloon is
substantially smaller than the force required to cause collapse of the
proximal portion of
the balloon.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, at least part of the distal portion and at least the
distal part of the
middle portion are corrugated such that the force required for causing
collapse of the
distal portion of the balloon is substantially smaller than the force required
to cause
collapse of the proximal portion of the balloon.
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Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the wall thickness of the balloon is non-uniform
along the length
of the balloon.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the wall thickness of the proximal part of the
balloon is greater
than the wall thickness of the distal part of the balloon.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the corrugations of the corrugated portion(s) of the
balloon have
a cross-sectional shape selected from the group consisting of symmetrical
triangular
corrugations, non-symmetrical triangular corrugations, curved corrugations,
sawtooth
like corrugations, symmetrical rounded corrugations, non-symmetrical partly
rounded
corrugations, and any combinations thereof.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the corrugations of thee corrugated portion(s) of
said balloon are
arranged intermittently such that corrugated and non-corrugated portions
alternate along
the corrugated portion(s).
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the inflatable balloon has a distal portion selected
from a dome-
like portion, a truncated dome-like portion, a conical portion, a frusto-
conical portion, a
corrugated dome-like portion, a corrugated conical portion, a corrugated
frusto-conical
portion and a truncated dome-like portion.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the corrugated portion(s) of the inflatable balloon
increase the
surface area of the balloon for improving retention of debris or particulate
material
trapped within the balloon after intussuscepting of said balloon.
Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the corrugated portion(s) of the inflatable balloon
increase the
probability of collapse of the distal portion of the balloon upon proximal
moving of the
inner conduit as compared to the probability of collapse of the distal portion
of a
similarly shaped balloon having no corrugated portion(s).
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Furthermore, in accordance with another embodiment of the balloon catheter of
the present application, the at least one corrugated portion of the inflatable
balloon is
configured to be internally disposed within the space formed in the
intussuscepted
balloon after the intussuscepting of the balloon is completed, such that no
corrugated
portion is presented on the external surface of the fully intussuscepted
balloon.
There is also provided, in accordance with the methods of the present
application,
a method of manufacturing an intussusceptible corrugated balloon catheter. The
method
includes the steps of:
providing a catheter having an outer conduit and an inner conduit, suitable
for
passage over a guide wire, the inner conduit is disposed within the lumen of
the outer
conduit such that the longitudinal axes of the inner and outer conduits are
substantially
parallel. The inner conduit is positioned such that the distal tip thereof
extends beyond
the distal tip of the outer conduit. The inner conduit is capable of being
moved along its
longitudinal axis in relation to the outer conduit. The catheter has an
inflation fluid port
in fluidic communication with the space formed between the inner surface of
the outer
conduit and the outer surface of the inner conduit;
providing an inflatable corrugated balloon having at least one corrugated
portion,
said corrugated balloon has a proximal margin and a distal margin; and
sealingly attaching said proximal margin of said balloon to the outer surface
of the
distal end of said outer conduit and sealingly attaching said distal margin of
said balloon
to the outer surface of the portion of the inner conduit that extends beyond
the distal end
of said outer conduit such that the lumen of said corrugated balloon is in
fluidic
communication with said space formed between said inner surface of said outer
conduit
and said outer surface of said inner conduit, said attaching is performed such
that the
distal end portion of said corrugated balloon is capable of intussuscepting
upon proximal
movement of said inner conduit in relation to said outer conduit.
There is also provided, in accordance with an embodiment of the methods of the
present application, a method for collecting debris from an internal passage
of a
mammalian subject. The method includes the steps of: inserting a corrugated
balloon
catheter including a balloon having at least one corrugated portion into the
internal
passage and advancing the catheter until the distal tip thereof has reached
the site, at
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which it is desired to collect debris, inflating the corrugated balloon with
expansion
fluid, pulling the inner conduit of the corrugated balloon catheter in a
proximal
direction, such that the distal end of the corrugated balloon intussuscepts
forming a
cavity into which debris is collected and entrapped, deflating the
intussuscepted
corrugated balloon, and removing the deflated corrugated balloon catheter from
the
internal passage of the subject together with the entrapped debris.
Furthermore, in accordance with an embodiment of the method, the internal
passage is a blood vessel.
Furthermore, in accordance with an embodiment of the method, the step of
pulling
includes pulling the inner conduit of the corrugated balloon catheter in a
proximal
direction to form the cavity, such that all of the corrugated portions of the
balloon are
disposed within the cavity to enhance retention of the debris.
Furthermore, in accordance with an embodiment of the method, the catheter
includes a mechanism for preventing substantial pressure changes when the
inner
conduit is moved proximally within the outer conduit while the balloon is
inflated and
the fluid port is closed and wherein the step of pulling includes pulling the
inner conduit
of the corrugated balloon catheter in a proximal direction for collapsing the
distal end of
the corrugated balloon to form a cavity within the balloon into which cavity
debris is
collected and entrapped without inducing substantial pressure changes within
the lumen
of the balloon during the intussuscepting.
There is also provided a corrugated element for use in constructing a
catheter, the
corrugated element includes a sleeve-like element including a first side
portion having a
first open end with a first diameter, a second side portion having a second
open end with
a second diameter smaller than the first diameter and a middle portion
disposed between
the first side portion and the second side portion. at least part of the
sleeve-like element
is corrugated.
Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, at least part of the second side portion is corrugated.
Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, at least part of the second side portion is corrugated
and at least part
of the middle portion is corrugated.
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Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, the wall thickness of the sleeve-like element is non-
uniform along a
longitudinal axis of the element.
Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, the wall thickness of the first side portion is greater
than the wall
thickness of the second side portion of the sleeve-like element.
Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, the corrugations of the corrugated part of the sleeve-
like element
have a cross-sectional shape selected from the group consisting of symmetrical
triangular
corrugations, non-symmetrical triangular corrugations, curved corrugations,
sawtooth
like corrugations, symmetrical rounded corrugations, non-symmetrical partly
rounded
corrugations, and any combinations thereof.
Furthermore, in accordance with an embodiment of the sleeve-like element of
the
present application, the corrugations of the corrugated part of the sleeve-
like element are
arranged intermittently such that corrugated and non-corrugated portions
alternate along
the corrugated part of said sleeve-like element.
Finally, in accordance with an embodiment of the sleeve-like element of the
present application, the shape of the second side portion of the sleeve-like
element is
selected from a dome-like shape, a truncated dome-like shape, a conical shape,
a frusto-
conical shape, a corrugated dome-like shape, a corrugated conical shape,
corrugated
frusto-conical shape and a corrugated truncated dome-like shape.
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BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to
the
accompanying drawings, in which like components are designated by like
reference
numerals, wherein:
Fig. 1 is a schematic side view diagram illustrating a corrugated inflatable
sleeve-like
usable as an intussusceptible balloon in a balloon catheter in accordance with
an
embodiment of the balloons of the present application;
Fig. 2 is a schematic cross section of the corrugated balloon of Fig. 1, taken
along the
lines II-I1;
Fig. 3 is a schematic cross-sectional diagram illustrating a catheter system
including
the corrugated intussusceptible inflatable balloon of Fig. 1 in accordance
with an
embodiment of the catheter systems of the present application;
Figs. 4-8 are a schematic cross-sectional diagrams illustrating different
steps of a
method of using a catheter system including the corrugated intussusceptible
inflatable
balloon of Fig. 1, in accordance with an embodiment of the method of the
present
application;
Figs. 9-12 are schematic side view diagrams illustrating different types of
corrugated
inflatable intussusceptible balloons, in accordance with additional
embodiments of the
balloon of the present application;
Figs. 13-15 are schematic cross-sectional diagrams illustrating different
types of
corrugated inflatable intussusceptible balloons having different types of
corrugations, in
accordance with further additional embodiments of the balloon of the present
application;
Figs. 16-19 are schematic cross-sectional diagrams illustrating additional
different
types of corrugated inflatable intussusceptible balloons having different
types of
corrugated balloon regions and/or different balloon wall thickness at
different portions of
the balloon, and/or multiple different types of folds on the same balloon, in
accordance
with yet further additional embodiments of the balloon of the present
application;
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Figs. 20-21 are schematic cross-sectional diagrams illustrating parts of
catheters with
different types of corrugated inflatable intussusceptible balloons having
partially
corrugated middle balloon portions and/or corrugated side portions, in
accordance with
yet additional embodiments of the corrugated balloon of the present
application;
Figs. 22-25 are schematic cross-sectional diagrams illustrating parts of
corrugated
balloons having different additional types of folds or corrugation shapes
and/or having
multiple corrugated portions interspersed with non-corrugated portions, in
accordance
with additional embodiments of corrugated balloons of the present application;
Fig. 26 is a schematic cross sectional diagram illustrating part of the wall
of a
corrugated balloon having alternating types of differently shaped
corrugations, in
accordance with an embodiment of the corrugated balloons of the present
application;
and
Fig. 27 is a schematic cross-sectional diagram illustrating a catheter system
including
the corrugated intussusceptible inflatable balloon of Fig. 1 having a
compliant member
usable as a pressure adjusting mechanism in accordance with another embodiment
of the
catheter systems of the present application.
25
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DETAILED DESCRIPTION OF THE INVENTION
It is noted that the terms "corrugated balloon" and "concertina-like balloon"
(in the
single as well as the plural forms) are interchangeably used herein to
indicate a balloon
or an inflatable element having multiple folds or corrugations formed at least
in a part or
a portion thereof. The folds or corrugations may be symmetrical or non-
symmetrical and
may be of any desired shape such as but not limited to folds having
triangular, or
rounded, or curved, or sawtooth like cross-sectional shape or any other
suitable cross-
sectional shape.
It is also noted that in the following description and in the claims of the
present
application, the terms "distal" and "proximal" are defined as follows: the
catheter side or
end which is inserted into the body first is referred to as the distal side or
distal end and
the trailing side or end of the catheters part of which remains outside the
body after
insertion of the catheter is referred to as the proximal side. For example, in
the balloon
catheter 30 of Fig. 3, the graduated scale 19 is disposed on the proximal side
of the
catheter 30 and the terminal cylindrical portion 10J is disposed near the
distal side or
distal end of the catheter 30.
Similarly, when referring to sides, parts or portions of the corrugated
balloons (or
sleeve-like elements) of the catheters of the present application, the term
distal refers to a
part, end or portion of the balloon (or sleeve-like element) which is inserted
first into the
body when the balloon catheter is operated. For example, the corrugated
balloon 10 of
Figs. 1-2 has a middle portion 10A, a proximal side portion 10B and a distal
side portion
loC.
Reference is now made to Figs. I and 2. Fig. 1 is a schematic side view
diagram
illustrating a corrugated inflatable balloon usable as an intussusceptible
balloon in a
balloon catheter in accordance with an embodiment of the balloons of the
present
application. Fig. 2 is a schematic cross section of the corrugated balloon of
Fig. 1, taken
along the lines II-II.
It is noted that while for the sake of clarity of illustration Figs. 1-2 and 9-
19 illustrate
only the sleeve-like elements 10, 34, 35, 36, 37, 40, 45, 47, 50, 60, 70 and
80 usable for
implementing the balloon catheters having corrugated inflatable
intussuscepting balloons
of the present application, all the sleeve-like elements 10, 34, 35, 36, 37,
40, 45, 47, 50,
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60, 70 and 80 may be assembled into such catheters in the same way(s) in which
the
balloon 10 of Figs. 1-2 is assembled into the balloon catheter 30 of Fig. 3.
It is further
noted that in view of the above, all the sleeve-like elements illustrated in
Figs. 1-2 and 9-
19 are also referred to in the application as balloons and the terms "balloon"
and "sleeve-
like element" in their singular and plural forms are interchangeably used
throughout the
specification.
The balloon 10 has a middle portion IOA and two side portions lOB and 10C. The
side portion lOB is also referred to as the proximal side portion IOB and the
side portion
IOC is referred to as the distal side portion IOC. A portion 1OD of the wall
of the
middle portion IOA is corrugated or folded in a concertina-like or accordion-
like
structure. The shape of the corrugations of the portion IOD may be generally
triangular
and symmetrical as may be seen in the cross-sectional view of Fig. 2. The
middle
portion 10A is the portion that has the largest diameter of the portions 11A,
lOB and
10C. The middle portion also includes a curving portion IOE. The proximal side
portion lOB includes a cylindrical portion 10F, a frusto-conical portion lOG
and a
terminal cylindrical portion 10H. The cylindrical portion 10H is the proximal
margin of
the balloon 10. The distal side portion IOC includes a truncated dome-like
portion 101
and a terminal cylindrical portion 10J. The cylindrical portion 10J is the
distal margin of
the balloon 10. The diameter of the terminal cylindrical portion 1OH is larger
than the
diameter of the terminal cylindrical portion 10J.
Preferably the balloon 10 is made from Nylon or another suitable
biocompatible
material, as is known in the art, such as, but not limited to, PET, PA12 (for
example
Grilamid L25, L55 and the like), PAl1, Polyether block amides (PEBA, such as
for
example, PEBAX 7233, 7033, 6333), various types of Grilflex (such as, for
example,
ELG 6260), and the like. However, any other suitable biocompatible material
known in
the art and suitable for fabrication of catheter balloons may be used in
implementing the
balloons of the present application.
The balloon 10 may be suitably attached to a catheter system 20 as disclosed
in detail
hereinbelow.
Reference is now made to Fig. 3 which is a schematic cross-sectional diagram
illustrating a catheter system including the corrugated intussusceptible
inflatable balloon
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of Fig. 1, in accordance with an embodiment of the catheter systems of the
present
application.
In the following description, the terms "conduit" and "tube" are used
interchangeably.
As shown in Fig. 3 the balloon catheter 30 comprises an inner tube 17 slidably
positioned inside an outer tube 18. The proximal (i.e., trailing) end of inner
tube 17
comprises an entry port 12, which extends outwardly through orifice 29
provided at the
proximal end of the outer tube 18. Orifice 29 tightly fits around the outer
surface of
inner tube 17 without gripping it, thereby allowing proximal and distal
movements of
inner tube 17 while sealing the inner lumen of outer tube 18.
The outer tube 18 may (optionally but not obligatorily) include an over-
pressure
valve outlet 15 or other suitable pressure adjusting mechanisms constructed
and operable
to relieve over-pressure as is disclosed in detail hereinafter. However, it is
noted that the
presence of such pressure adjusting mechanisms is not obligatory to practicing
the
invention, and that other embodiments may be constructed and operated without
such a
pressure adjusting mechanisms by suitable designing the balloon 10 and other
catheter
components to withstand over-pressure. Therefore, In accordance with an
additional
embodiment (not shown in Fig.3) of the catheter, the outer conduit 18 of the
catheter 30
does not include the over-pressure valve outlet 15 or any other type of
pressure adjusting
mechanism.
It is noted that a graduated scale 19 may optionally be provided on the outer
surface
of inner tube 17 as illustrated and described in detail in the above
referenced
international patent application published as WO 2007/7004221 and as explained
hereinafter with reference to Fig. 3 of the present application.
The proximal end of outer tube 18 further comprises a fluid port 11 for
injecting/removing inflation fluids to/from the inner lumen of outer tube 18,
an over-
pressure valve outlet 15 for discharging inflation fluids whenever over-
pressure
conditions develop in the inner lumen of outer tube 18, and an inner tube
safety lock 14
adapted for gripping the outer surface of inner tube 17, thereby preventing
proximal-
distal movements thereof relative to outer tube 18. The precise structure and
operation
of the safety lock 14 is as disclosed in detail in WO 2007/7004221.
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When the balloon 10 is inflated and the fluid port 11 is closed, an over-
pressure may
develop within the balloon 10 when the inner conduit 17 is pulled proximally
within the
outer conduit 18 for intussuscepting the balloon 10.
In certain embodiments of the catheters of the present application (not shown
in Fig.
3), there is no the over-pressure adjusting mechanism and the over-pressure
may be
resolved by slight expansion of some parts of the catheter (such as but not
limited to, the
outer conduit 18) if these parts are made of sufficiently compliant material.
While in
some embodiments of the catheters of the present application, the pressure
inside the
lumen of the balloon 10 may increase during the intussuscepting of the
balloon, such
pressure increase may be safely accommodated by using a balloon 10 capable of
safely
withstanding the over-pressure resulting from the intussuscepting of the
balloon 10.
For example, the wall thickness of the balloon 10 may be made sufficiently
thick to
safely withstand the over-pressure or the balloon 10 may be made from a
material having
sufficient strength to effectively withstand the over-pressure resulting from
the
intussuscepting of the balloon 10.
However, preferably, in accordance with additional embodiments of the balloon
catheter of the present invention, a pressure adjusting mechanism may be used
in the
catheter 30 of Fig. 3. In accordance with one embodiment of the catheter 30 of
the
present application, the pressure adjusting mechanism includes an over-
pressure valve
outlet 15 and an over-pressure valve 16 disposed therein. The over-pressure
valve outlet
15 may include an over-pressure valve 16 for sealing the opening of over-
pressure valve
outlet 15 and for discharging portions of inflating fluids therethrough
whenever over-
pressure conditions are reached in inner lumen of outer tube 18. The over-
pressure valve
outlet 15 is in fluidic communication with the lumen of the inflatable balloon
10 through
the space formed between the inner surface of the outer tube 18 and the outer
surface of
the inner tube 17, and the over-pressure valve 16 disposed within the over-
pressure outlet
15 may allow discharging of fluid from the lumen of the balloon 10 when over-
pressure
conditions develop in the lumen of the balloon 10 during the intussuscepting
of the
balloon 10.
It should be realized however that such over-pressure conditions may be
resolved
by other means. For example, an inflatable member may be attached to the
opening of
16
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over-pressure valve outlet 15, and in such an implementation over-pressure
valve 16 may
be eliminated. Reference is now made to Fig. 27 which is a schematic cross-
sectional
diagram illustrating a catheter system including the corrugated
intussuscepting inflatable
balloon of Fig. 1 and having an additional compliant member usable as a
pressure
adjusting mechanism in accordance with another embodiment of the catheter
systems of
the present application. The catheter 39 is similar in construction and
operation to the
catheter 30 of Fig. 3, except that the over-pressure valve 16 of Fig. 3 is
replaced by a
compliant member 9 such as (but not limited to) an inflatable and expandable
balloon
made from latex or from any other suitable expandable material. The compliant
member
9 is sealingly attached to the outlet 15 to seal the outlet 15. In this
embodiment, the
outlet 15 is in fluidic communication with the lumen of the inflatable balloon
10. When
the balloon 10 of the catheter 39 is intussuscepted while it is in the
inflated state (by
pulling the inner tube 17 proximally), the compliant member 9 may expand to
accommodate some of the inflating fluid thus relieving some of the over-
pressure in the
lumen of the balloon 10.
Moreover, in accordance with yet another embodiment of the catheters of the
present
application, the outer tube 18, or portions thereof, may be made inflatable or
expandable
or compliant, such that over-pressure conditions may be at least partially
resolved by the
expansion of the tube 18 or of a compliant portion thereof.
The inner tube safety lock 14 contacts the outer surface of inner tube 17 via
a tight
orifice provided on the outer surface at the proximal end of outer tube 18. It
is noted that
the details of construction and operation of the safety lock 14 are fully
explained and
illustrated in Figs IA and 113 of the above referenced International Patent
Application
published as WO 2007/7004221, and are therefore not disclosed in detail
hereinafter.
As seen in Fig. 3, the distal (leading) end (distal tip) of the inner tube 17
extends
outwardly through the distal opening of outer tube 18. The corrugated balloon
10 (of
Figs. 1-2), is attached to the distal ends of outer tube 18 and the inner tube
17. The
portion 1OH of the corrugated balloon 10 is attached at a circumferential
attachment
region 7 to the outer surface near the distal tip of outer tube 18. The
portion 10J of the
corrugated balloon 10 is attached at circumferential attachment region 6 to
the outer
surface near the distal tip of inner tube 17, such that it seals the distal
opening of the outer
17
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tube 18. The attachment of the balloon 10 to the tips of the inner tube 17 and
the outer
tube 18 may be implemented using any suitable sealing attachment method known
in the
art, including but not limited to heat bonding, welding, ultrasonic welding,
gluing, or any
other method known in the art and capable of producing a sealed attachment
capable of
withstanding the pressures required for operating the inflatable expandable
balloon(s) of
the present application.
In accordance with another embodiment of the catheter systems of the present
application, the catheter may include a pressure adjusting mechanism
comprising a
syringe-like structure. The syringe-like structure is disposed at the proximal
end of the
balloon catheter. The syringe-like structure may include a barrel and a
plunger disposed
within the barrel. The plunger co-axially surrounds the proximal end of the
inner conduit
17, and is affixed thereto. This embodiment is fully disclosed in detail in
the above
referenced International Patent Application published as WO 2007/7004221
incorporated
herein by reference in its entirety (in Fig IC thereof), and is therefore not
described in
detail hereinafter. Briefly, the syringe- like structure of Fig. IC of WO
2007/7004221
is positioned at the proximal end of the catheter system, wherein the barrel
portion 26 (of
Fig. 1C of WO 2007/7004221) of the syringe-like structure is formed by an
expanded
portion of the outer conduit 18, and wherein the plunger 17a (of Fig. IC of WO
2007/7004221) of the syringe- like structure co-axially surrounds the proximal
end of the
inner conduit 17. However, the barrel portion 26 may also be implemented as a
separate
member suitably sealingly attached to the outer conduit 18.
Reference is now made to Figs. 4-8 which are a schematic cross-sectional
diagrams
illustrating different steps of a method of using a catheter system including
the
corrugated intussusceptible inflatable balloon of Fig. 1, in accordance with
an
embodiment of the method of the present application. Figs. 4-8 illustrate the
insertion of
the balloon catheter 30 to a treatment site, for example a blood vessel 20. It
is noted that
while the illustrations of the application use the blood vessel 20 as an
example of the
treated site, this is done by way of exemplary demonstration only, and other
body
passages may also be treated by the catheters, and catheter systems of the
present
application.
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Turning to Fig. 4, an exemplary interventional procedure using the corrugated
balloon
catheter 30 of the present application starts as the balloon catheter 30 is
guided to the
treatment site within the blood vessel 20 (e.g., over the wire). Fig. 4
illustrates over-the-
wire insertion, wherein the insertion of the balloon catheter 30 is performed
over a guide
wire 13. It should be clear, however, that the invention is not limited to one
specific
insertion method and that other appropriate and practicable catheter insertion
methods
known in the art (such as, but not limited to, using a guiding catheter) may
also be used.
The catheter is advanced over the guide wire 13 until the (non-inflated)
middle portion
5A is positioned within an atheromatous plaque 23 attached to the inner
surface 21 of the
blood vessel 20.
Turning to Fig. 5, the operator inflates the corrugated balloon 10 by
injecting inflation
fluids via fluid port 11 (see Fig. 3) and the inner lumen of outer tube 18.
When carrying
out procedures in blood vessel 20 as demonstrated in the Figs. 4-8, inflation
fluids are
preferably injected into the corrugated balloon 10 such that the
circumferential corrugated
sides of the portion 1OA of the corrugated balloon 10 are expanded and pressed
against
the inner surface 21 of blood vessel 20 and against the plaque 23, as
illustrated in Fig. 5.
The pressure inside the corrugated balloon 10 in such conditions may be in
general about
1-25 Atmospheres, preferably about 6 Atmospheres.
It is noted that while in the embodiment of the treatment method illustrated
in Figs. 4-
8 the middle portion IOA of the corrugated balloon 10 is placed within the
region of the
plaque 23 and is used to treat the plaque 23 by pushing the plaque 23 towards
the walls of
the blood vessel 20 to open a larger passage within the atheromatous portion
of the blood
vessel 20, other different treatment methods are also possible, in which the
portion IOA is
not used as a plaque treating or plaque pushing means, but is used as an
anchoring portion
of the corrugated balloon 10 enabling firm anchoring of the catheter 30 to the
walls of the
blood vessel 20 which in turn allows other different plaque treating devices
(not shown in
Fig. 4-8) to be inserted into the lumen of the inner tube 17 (after withdrawal
of the guide
wire 13) for treating the plaque. In such alternative treatment methods, the
portion 1OA
of the balloon is typically positioned within the blood vessel 20 at a site
proximal to the
position of the plaque 23, and plaque treatment is performed by an additional
treating
device (such as, but not limited to, a rotablator burr, a mechanical cutting
device, a laser
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device such as an excimer laser or other laser for performing ELCA or other
types of laser
based atherectomies, Radiofrequency angioplasty device, an ultrasonic ablator
device,
and the like) inserted into the lumen of the inner tube 17.
In the state in which the balloon catheter 30 is anchored, the inner lumen of
the inner
tube 17 may now be utilized for operating in the treated site with different
interventional
tools (not shown in Figs 4-8), as may be required. However, some procedures
(for
example angioplasty) may be completed, or may be near completion, once balloon
10
reaches its fully inflated state.
Irrespective of which particular method of plaque treatment is used, after
plaque
treatment is achieved, a sample of liquid or solid matter, for example fluids,
secretions,
and/or debris 25 (resulting from plaque breakup due to treatment steps) may be
collected
and removed from the treatment site by causing the balloon 10 to intussuscept.
The inner
tube safety lock 14 (see Fig. 3) is pulled out, thereby releasing its grip
from inner tube 17.
The inner tube 17 is then retracted outwardly (proximally) by the operator as
shown by
arrow 28 of Fig. 6. During retraction of inner tube 17 the distal portion of
balloon 10
collapses and the outer surface portions of the balloon 10 are folded inwardly
over the
distal tip of inner tube 17 and thereafter over itself as further portions of
the balloon
collapse, as illustrated in Figs. 6-7.
It is noted that the corrugated form of the balloon 10 advantageously assists
the proper
folding of the balloon 10 because the corrugated shape results in reducing the
force
required for initiating the internal folding of the distal end of the balloon.
The proximal retraction of the inner tube 17 and the resulting inward folding
of
balloon 10 shortens the overall length of inflated balloon 10 which actually
reduces the
volume of inflated balloon 10. Consequently, the pressure exerted by the
inflating fluids
increases, resulting in a considerable pressure increase in the balloon 10 and
inner lumen
of outer tube 18. Whenever the pressure in the balloon 10 and the inner lumen
of outer
tube 18 reaches a certain set-point (e.g., 5-20 atmospheres) inflation fluids
flow towards
the proximal side of the balloon 10 and are discharged via over-pressure valve
outlet 15,
such that the pressure in the balloon 10 and the inner lumen of outer tube 18
remains
within a predetermined pressure range (e.g., 5-20 atmospheres). Optionally, in
catheters
including the graduated scale 19 (see Fig. 3), the operator can determine by
monitoring
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the graduated scale 19, the amount of length of the inner tube 17 that has
been retracted
and in this way the operator may determine when to stop the retraction and
restore
immobilization (locking) of the inner tube 17 by pushing down the inner tube
safety lock
14 (of Fig. 3), as explained in the catheter systems disclosed in detail in WO
2007/7004221.
It is noted, however, that in embodiments of the catheters having no over-
pressure
valve outlet 15 and no over-pressure valve 16 and no other pressure adjusting
mechanism,
the balloon 10 may have a substantially increase in the pressure during the
period in
which it is intussuscepted while the fluid port 11 is sealed.
Turning to Fig. 6, during the retraction of the inner tube 17 in the proximal
direction
indicated by the arrow 27, the dome-like portion 101 of the balloon 10 inverts
starting the
intussuscepting of the balloon 10.
Turning to Fig. 7, during the retraction of during the retraction of the inner
tube 17 in
the proximal direction indicated by the arrow 27, the additional portions of
the balloon 10
continue to intussuscept as illustrated, such that portion 101, and part of
the portion 1OD
form an internal cavity 41. As the inner tube 17 continues to be pulled in the
proximal
direction indicated by the arrow 27, the internal cavity 41 increases in
length and its
volume increases until the retraction of the inner tube 17 is stopped and the
operator
restores immobilization (locking) of the inner tube 17 by pushing down the
inner tube
safety lock 14 (of Fig. 3), as explained in the catheter systems disclosed in
detail in WO
2007/7004221. At this locked state (not shown) the fluids contained within the
walls of
the intussuscepted balloon 10 and may be withdrawn through the open annular
passage 33
formed between the inner tube 17 and the outer tube 18.
Some of the debris 25 resulting from the compaction and breakup of the plaque
23
during the full inflation of the balloon 10, (as illustrated in Fig. 5),
adheres to the
extended surface area of the corrugated portion 1OD and is carried by the
intussuscepted
part of the portion 1OD into the cavity 41 being formed within the
intussuscepting
balloon 10. It is noted that the corrugation of the portion IOD advantageously
assists the
intussuscepting of the balloon 10 by reducing the puling force required for
the internal
folding of the balloon, as compared to the force required for the internal
folding of a
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WO 2010/001405 PCT/IL2009/000668
non-corrugated balloon (having substantially similar dimensions but including
no
corrugations), such as the balloons disclosed in WO 2007/7004221.
It will be appreciated by those skilled in the mechanical art that the
corrugated
portion(s) of the corrugated inflatable balloons disclosed in the present
application
increase the probability of collapse of the distal portion of the balloon upon
proximal
moving of the inner conduit 17 as compared to the probability of collapse of a
distal
portion of a similarly shaped balloon having no corrugated portion(s).
Furthermore, the corrugations of the portion 10D, increase the surface area of
the part
of the balloon 10 which is in contact with the wall of the blood vessel 20
when the
balloon 10 is in the inflated state, and thus advantageously increases the
surface area
onto which the debris 25 and other particular matter released from the
compacted and/or
disrupted plaque 23 may adhere and may result in advantageously increasing the
amount
of debris 25 and/or plaque particulate material that is carried into and
trapped within the
cavity 41 internally formed within the balloon 10 after the intussuscepting of
the balloon
10.
Turning to Fig. 8, after the intussuscepting of the balloon 10 has been
completed, the
balloon 10 is deflated by retracting inflation fluids through the fluid port
11 (of Fig. 3) as
explained in detail in WO 2007/7004221. In result, the pressure inside the
balloon 10 and
in the inner lumen of outer tube 18 is substantially decreased, and the
intussuscepted
balloon 10 is deflated. After the balloon intussuscepting and deflation, the
operator may
retract (withdraw) the balloon catheter 30 proximally in the direction of the
arrow 31 such
that the portion of fluid/secretion and the debris 25 confined within the
cavity 41 are
withdrawn with the balloon catheter 30 outside of the treated body (not shown
in the
figures). The debris 25, or objects or samples may be easily collected when
the entire
length of balloon catheter 30 is withdrawn from the body of the treated
subject, by
pushing the inner tube 17 distally and unfolding the folded portions of
balloon 5, thus
restoring the deflated state of balloon 10 (shown in Fig. 3).
It is noted that as may be seen in Fig. 8, after the intussuscepting of the
balloon 10,
the corrugated portion 10D of the balloon 10 is completely internally disposed
within the
cavity 41 formed in the intussuscepted balloon 10 such that no corrugated
portion or
surface is presented on the external surface of the fully intussuscepted
balloon 10. This
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may be advantageous, as such a configuration may assist the withdrawal of the
deflated
balloon 10 and catheter 30 from within the blood vessel 20 (or from any other
bodily
cavity in which it was inserted), by ensuring that no corrugations are
presented on the
outside surface of the deflated intussuscepted balloon 10. However, while this
feature
of the balloon 10 is preferred, this feature is not obligatory and in some
embodiments of
the catheters of the present invention, the entire surface of the balloon may
be corrugated
( as described in detail hereinafter) or a substantial part of the length of
the balloon may
be corrugated, such that at least part of the corrugated surface is present on
the outer
surface of the intussuscepted balloon facing the internal blood vessel 20
after
intussuscepting of the balloon and after deflating the balloon.
In view of the axially-directed stretching and buckling forces exerted on the
inner and
outer tubes during elongation and shortening of the balloon, said tubes need
to be
constructed such that they are able to withstand axially-directed forces in
the range of
between 2 and 20 Newton without undergoing deformation. In order to achieve
this aim,
the conduits may be constructed of a braided material or of materials having a
defined
molecular orientation. The approximate maximum forces that the inner and outer
tubes
need to withstand (for two difference size ranges of balloon inflated
diameter, when the
inflated diameter is defined as the diameter of the balloon midsection at the
balloon's
nominal pressure) are as follows:
I) 2.5-4 mm diameter balloons: the tubing should withstand forces of up to 500
gram;
polymer tubing made of Nylon or Pebax (a thermoplastic polyether block amide
polymer) reinforced during the manufacturing process can be used.
II) 4-8 mm diameter (or larger) balloons: the tubing should withstand forces
up to 2
kilogram. In this case it may be necessary to use a braided tube (polymer tube
with metal
mesh reinforcement).
Exemplary results for a representative study of the forces generated during
balloon
folding are presented in Example 2, of WO 2007/7004221 incorporated herein by
reference in its entirety.
The outer tube 18 is preferably made from a biocompatible polymer type of
material,
such as polyurethane or nylon or PET, and may be manufactured using
conventional
methods, such as extrusion. The diameter of the inner lumen of outer tube 18
is generally
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in the range of 0.5-2.0 mm (millimeters), preferably about 0.7 mm, and the
diameter of
the fluid port 11 is generally in the range of 2-6 mm, preferably about 4 mm.
The
diameter of the over-pressure valve outlet 15 is generally in the range of 1-6
mm,
preferably about 4 mm, and the entire length of the outer tube 18 is generally
in the range
of 100-2000 mm, preferably about 1400 mm.
The inner tube 17 is preferably made from a biocompatible polymer type of
material,
such as polyurethane or Nylon or PET, and it may be manufactured using
conventional
methods, such as extrusion. The diameter of the inner lumen of inner tube 17
is generally
in the range of 0.2-2.0 mm, preferably about 0.5 mm, and its entire length is
generally in
the range of 100-2000 mm, preferably about 1500 mm.
However, it will be appreciated by those skilled in the art that all values
and
dimensions of the various parts of the catheters and the values of the forces
acting on the
various parts as disclosed herein, are given by way of practical examples only
and it may
be possible to implement the catheters and balloons of the present invention
by using
other different values and/or value ranges of dimensions of the various parts
of the
catheters and/or forces to be withstood by such parts and/or different
structural materials
for constructing and implementing the catheters disclosed herein and any of
their parts
and/or components.
While the diameter of the orifice 29 provided at the proximal tip of the outer
tube 18
should be adapted to provide appropriate sealing of inner lumen of the outer
tube 18 it
should also close over the outer surface of the inner tube 17 such that inner
tube 17 may
be displaced therethrough with relatively low frictional forces. For example,
if the
diameter of the inner tube 17 is 0.7 mm, then the diameter of the orifice 29
should be 1.0
mm.
The balloon 10 is preferably a non-compliant or semi-compliant balloon such as
manufactured by Advanced Polymers (Salem, USA) and by Interface Associates
(CA).
The balloon 10 may be manufactured using conventional methods known in the
balloon
catheter industry (such as, for example, pressure induced thermoforming - by
forming the
balloon shape using a suitably corrugated mold and a cylindrical tube made
from a
thermoplastic material which is shaped within the heated mold by suitable
application of
pressure). The balloon 10 may be made from a non-compliance type of material
such as
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Pebax or Nylon (preferably Nylon 12), but any other suitable material known
in the art
may also be used. The length of the balloon 10 is generally in the range of 10-
60 mm,
preferably about 20 mm, but other different lengths may also be used. The
diameter of
the corrugated portion IOD of the balloon 10 may vary between 2.0 min to 5 mm
for
coronary artery applications, but may be significantly larger for use in
larger blood
vessels. Preferably (but not obligatorily), the balloon 10 should have a burst
pressure
within the range of 12-20 atmospheres. The proximal and distal edges of the
balloon 10
such as the cylindrical portions 10H and 10J, respectively, of the balloon 10,
are
preferably sealingly attached to the outer surfaces of outer tube 18 and of
the inner tube
17 respectively, at circumferential attachment points 7 and 6 respectively, by
using, heat
bonding, or a UV or thermo bonding type of adhesive such as commonly used in
the art.
Thus, the advantages of the corrugated balloons described herein are providing
facilitated balloon folding and intussuscepting by reducing the force required
for folding
of the corrugated portion of the balloon and the providing of an increased
surface area
(relative to a non-corrugated balloon) of the corrugated portion which may
substantially
assist the adherence and inclusion of debris particles within the
intussuscepted
corrugated balloon.
It is noted that while the corrugated balloon 10 and the catheter 30 including
it are
shown by way of example, they are not intended to limiting by any way. Rather,
many
other different types of corrugated balloons may be advantageously implemented
in the
catheters of the present application.
Reference is now made to Figs. 9-12 which are schematic side view diagrams
illustrating different types of corrugated inflatable intussusceptible
balloons usable in the
catheters and systems of the present application, in accordance with
additional
embodiments of the balloon of the present application.
Turning to Fig. 9, the corrugated balloon 34 includes contiguous portions 34H,
34G,
34F, 34E, 34D, 341 and 34J. The cylindrical portion 34H is shorter than the
cylindrical
portion 10H (of Fig. 2). The frusto-conical portion 34G is longitudinally
shorter than the
frusto-conical portion lOG (of Fig. 2) and therefore has a steeper cone angle.
The
cylindrical portion 34F is longer than the cylindrical portion 10F (of Fig.
2). The
portions 34D, 341 and 34J are similar in shape to the corresponding portions
10D, 101
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and 1OJ, respectively, of Fig. 2. As seen in the inset of Fig. 9, the
corrugations 34N have
a symmetrical triangular shape, in accordance with an embodiment of the
balloons of the
present application.
Turning to Fig. 10, the corrugated balloon 35 includes contiguous portions
35H,
35G, 35E, 35D, 351 and 35J. The cylindrical portion 35H is similar in length
to the
cylindrical portion 1OH (of Fig. 2). The frusto-conical portion 35G is similar
to the
frusto-conical portion lOG (of Fig. 2) However, it is noted that the frusto-
conical portion
35G is contiguous with the portion 35E (without a cylindrical portion between
them as in
the balloon 10 of Fig. 2). The portions 35D, 351 and 35J are similar in shape
to the
corresponding portions 1OD, 101 and 1OJ, respectively, of Fig. 2. As seen in
the inset of
Fig. 10, the corrugations 35N have a symmetrical rounded shape, in accordance
with
another embodiment of the balloons of the present application.
Turning to Fig. 11 the corrugated balloon 36 includes contiguous portions 36H,
36G,
36F, 36E, 36D, 361 and 36J. The cylindrical portion 36H is shorter than the
cylindrical
portion 1OH (of Fig. 2). The portion 36G is shaped like a truncated dome
(having a
convex shape) and is longitudinally shorter than the frusto-conical portion
lOG (of Fig.
2). The cylindrical portion 36F is shorter than the cylindrical portion 1OF
(of Fig. 2).
The portions 36D, 361 and 36J are similar in shape to the corresponding
portions 34D,
341 and 34J respectively, of Fig. 9.
Turning to Fig. 12 the corrugated balloon 37 includes contiguous portions 37H,
37G,
37F, 37E, 37D, 371 and 37J. The cylindrical portion 37H is shorter than the
cylindrical
portion 1OH (of Fig. 2). The portion 36G has a tapered shape (having a concave
shape)
and is longitudinally shorter than the frusto-conical portion 1OG (of Fig. 2).
The
cylindrical portion 37F is shorter than the cylindrical portion 1OF (of Fig.
2). The
portions 37D, 371 and 37J are similar in shape to the corresponding portions
34D, 341
and 34J respectively, of Fig. 9.
It may thus be seen that the dimensions and shapes of the different portions
of the
balloons of the present application may be varied, including the shape and
number of the
corrugations included in the corrugated portion of the balloon. Such
variations may
depend on and may be used in different applications of the catheters
(including the use
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for treatment of different blood vessels and/or other types of body-passage of
varying
sizes and dimensions.
Reference is now made to Figs. 13-15 which are schematic cross-sectional
diagrams
illustrating different types of corrugated inflatable intussusceptible
balloons having
different types of corrugations, in accordance with further additional
embodiments of the
balloon of the present application.
Turning to Fig. 13, the corrugated balloon 40 includes contiguous portions
40H,
40G, 40F, 40D, 401 and 40J. The portions 40H, 40G, 40F, 401 and 40J are
similar the
corresponding portions 1OH, 10G, IOF, 101 and 10J (of Fig. 2), respectively.
However,
the number and shape of the corrugations 40N of the portion 40D are different
then those
of the corresponding portion IOD (of Fig. 2). Each of the corrugations 40N is
wider than
the corrugations ION (i.e, the length L2 of each of the corrugations 40N is
longer than
the length Ll of the corrugations ION of Fig. 2)
Turning to Fig. 14, the corrugated balloon 45 includes contiguous portions
45H,
45G, 45F, 45D, 451 and 45J. The portions 45H, 45G, 45F, 451 and 45J are
similar the
corresponding portions 1OH, lOG, IOF, 101 and 1OJ (of Fig. 2), respectively.
However,
the shape (and possibly the number) of the corrugations 45N of the portion 45D
are
different then those of the corresponding portion 10D (of Fig. 2). Each of the
corrugations 40N is formed such that it has a sawtooth-like cross-sectional
shape with
the direction of the sawtooth shape arranged as illustrated in Fig. 14.
Turning to Fig. 15, the corrugated balloon 47 includes contiguous portions
47H,
47G, 47F, 47D, 471 and 47J. The portions 47H, 47G, 47F, 471 and 47J are
similar the
corresponding portions 10H, 10G, IOF, 101 and 10J (of Fig. 2), respectively.
However,
the shape (and possibly the number) of the corrugations 47N of the portion 47D
are
different then those of the corresponding portion IOD (of Fig. 2). Each of the
corrugations 40N is formed such that it has a sawtooth-like cross-sectional
shape with
the direction of the sawtooth shape reversed in comparison to the direction of
the
sawtooth shapes formed on the portion 45D of the balloon 45(of Fig. 14), as
illustrated
in Fig. 15.
Reference is now made to Fig. 16-19 which are schematic cross-sectional
diagrams
illustrating additional different types of folded or corrugated inflatable
intususseptable
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balloons having different types of corrugated balloon regions and/or different
balloon
wall thickness at different portions of the balloon, and/or multiple different
types of folds
on the same balloon, in accordance with yet further additional embodiments of
the
balloon of the present application.
Turning to Fig. 16, the corrugated balloon 50 includes a middle potion 50A, a
proximal side portion 50B and a distal side portion 50C. The proximal side
portion 50B
comprises contiguous portions 50H, 50G and 50F. The middle portion 50A
comprises
contiguous portions 50M and 50D. The portion 50M is not corrugated and the
portion
50D is corrugated as disclosed hereinabove. The distal side portion 50C
comprises a
corrugated curved portion 501 which is contiguous with the corrugated portion
50D, and
a non-corrugated cylindrical portion 50J.
The portions 50H, 50G, 50F, and 50J are similar the corresponding portions
40H,
40G, 40F, and 40J of the balloon 40 (of Fig. 13), respectively. However, while
the
truncated dome-like portion 401 of Fig. 13 is not corrugated, the portion 501
has a
corrugated dome like shape. This corrugated truncated conical structure may
further
facilitate the folding and intussuscepting of the balloon 50. The shape and
dimensions of
the corrugations 50K of the potion 501 may be similar to the shape and
dimensions of the
corrugations 50N of the portion 50D. However, this is not obligatory and the
shape and
dimensions of the corrugations 50K of the potion 501 may be different than the
shape
and dimensions of the corrugations 50N of the portion 50D (such as, but not
limited to,
the corrugations 50K of the potion 501 being smaller than and/or having a
different
shape then the corrugations 50N of the portion 50D).
Turning to Fig. 17, the corrugated balloon 60 includes a middle potion 60A, a
proximal side portion 60B and a distal side portion 60C. The corrugated
balloon 60 has
a non-uniform wall thickness along it's length. The proximal side portion 60B
comprises contiguous portions 60H, 60G and 60F. The middle portion 60A
comprises
contiguous portions 60M and 60D. The portion 60M is not corrugated and the
portion
60D is corrugated, as disclosed hereinabove. The distal side portion 60C
comprises a
truncated dome-like portion 601 which is contiguous with the corrugated
portion 60D,
and a non-corrugated cylindrical portion 60J.
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The portions 60D, 601 and 60J are similar in shape and dimensions the
corresponding portions 10D, 101 and lOJ of the balloon 10 (of Figs. 1-2),
respectively.
However, the portions 60H, 60G, OF and 60M have walls which are thicker than
the
walls of the corresponding portions 1OH, lOG, 10F and l0E of the balloon 10
(of Fig.2).
The extra thickness of the walls of the balloon portions 60H, 60G, 60F and 60M
of the
balloon 60 mechanically reinforce the proximal side portion 60B and the
portion 60M
and advantageously prevents (or reduces the probability of) the folding of the
proximal
side of the balloon 60 and ensures that when the balloon is attached to a
catheter similar
to the catheter 30 of Fig. 3) and a pulling force is applies to the distal
side of the balloon
60 by moving the inner tube 17 (see Fig. 3) of the catheter in the proximal
direction, as
disclosed hereinabove, the distal side of the balloon 60 will fold (by
collapsing)
preferentially at a lower force than the force required to cause folding of
the balloon at
the thicker walled region of the proximal side portion 60B and the portion
60M.
Turning to Fig. 18, the corrugated balloon 70 includes a middle potion 70A, a
proximal side portion 70B and a distal side portion 70C. The proximal side
portion 70B
comprises contiguous portions 70H, 70G and 70F. The middle portion 70A
comprises
contiguous portions 70M and 70D. The portion 70M is not corrugated and the
portion
70D is corrugated as disclosed hereinabove. The distal side portion 70C
comprises a
corrugated truncated conical portion 701 which is contiguous with the
corrugated portion
70D, and a non-corrugated cylindrical portion 70J.
The portions 70H, 70G, 70F, and 70J are similar the corresponding portions
40H,
40G, 40F, and 40J of the balloon 40 (of Fig. 13), respectively. However, while
the
portion 401 of Fig. 13 has a non-corrugated truncated dome-like shape, the
portion 701
has a corrugated truncated conical shape. As explained hereinabove with regard
to the
corrugated dome-like portion 501 of the balloon 50, the corrugated structure
of the
portion 701 may similarly facilitate the folding and intussuscepting of the
balloon 70.
The shape and dimensions of the corrugations 70K of the potion 701 may be
similar to
the shape and dimensions of the corrugations 70N of the portion 70D. However,
this is
not obligatory and the shape and dimensions of the corrugations 70K of the
potion 701
may be different than the shape and dimensions of the corrugations 70N of the
portion
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70D (such as, but not limited to, the corrugations 70K of the potion 501 being
smaller
than and/or having a different shape then the corrugations 50N of the portion
50D).
Turning to Fig. 19, the corrugated balloon 80 includes a middle potion 80A, a
proximal side portion 80B and a distal side portion 80C. The proximal side
portion 80B
is identical to the proximal portion lOB (of Fig. 2) and comprises contiguous
portions
80H, 80G and 80F. The distal side portion 80C is identical to the distal
portion 10C (of
Fig. 2) and includes the portions 801 and 80J. However, the middle portion 80A
comprises portion 80M which is identical to the portion 1OE of Fig. 2, and two
contiguous corrugated portions 80D and 80P.
The corrugations of the portion 80D are similar in shape to the symmetrical
triangular corrugations 50N of Fig. 16. In contrast, the corrugations of the
portion 80P
are symmetrical rounded or curved corrugations similar to the corrugations 35N
(illustrated in the inset of Fig.10).
It is noted that other embodiments with other mixed types of corrugations are
also
possible in the balloons (and sleeve-like elements) of the present
application. For
example, in accordance with an embodiment of the balloons of the present
application
the middle portion of the balloon may include three contiguous portions (not
shown), a
first portion with rounded corrugations, a second portion with symmetrical
triangular
corrugations and a third portion with sawtooth-like corrugations. Thus, many
other
combinations and sub-combinations of multiple corrugated portions (either
contiguous or
non-contiguous) with multiple different types of corrugations may be
implemented in the
balloons and balloon catheters of the present application.
It is noted that while in the embodiments of the balloons (and sleeve-like
elements)
disclosed hereinabove, the corrugated portion(s) occupied most of the
longitudinal
dimension of the balloon's middle portion (the portion having the largest
diameter of all
the balloon portions), this is by no means obligatory. Rather, only a part of
the middle
portion may be corrugated resulting in a partially corrugated middle portion.
Similarly,
embodiments are possible in which the middle portion of the balloon is
completely non-
corrugated while the distal portion of the balloon or a part thereof is
corrugated.
Reference is now made to Fig. 20-21 which are schematic cross-sectional
diagrams
illustrating parts of catheters with different types of corrugated inflatable
intussusceptible
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balloons having partially corrugated middle balloon portions and/or corrugated
side
portions, in accordance with yet additional embodiments of the corrugated
balloon of the
present application.
Turning to Fig. 20, the corrugated balloon 140 includes a middle potion 140A,
a
proximal side portion 140B and a distal side portion 140C. The proximal side
portion
140B is identical to the proximal portion 40B (of Fig. 13) and comprises
contiguous
portions 140H, 140G and 1400F. The distal side portion 140C is identical to
the distal
portion 10C (of Fig. 2) and includes the portions 1401 and 140J. However, the
middle
portion 140A comprises a non-corrugated portion 140D and a contiguous
corrugated
portion 141D. In the specific non-limiting embodiment illustrated in Fig. 20,
the non-
corrugated portion 140D occupies approximately two thirds of the length of the
middle
portion 140A, and the corrugated portion 141D occupies approximately a third
of the
length of the of the middle portion 140A. However, this is not obligatory and
other
different length relationship between the corrugated portion and the non-
corrugated
portion of the middle portion 140A are also possible.
Turning to Fig. 20, the corrugated balloon 140 includes a middle potion 140A,
a
proximal side portion 140E and a distal side portion 140C. The proximal side
portion
140B is identical to the proximal portion 40B (of Fig. 13) and comprises
contiguous
portions 140H, 140G and 140F. The distal side portion 140C is identical to the
distal
portion IOC (of Fig. 2) and includes the portions 1401 and 140J. However, the
middle
portion 140A comprises a non-corrugated portion 140D and a contiguous
corrugated
portion 141D. In the specific non-limiting embodiment illustrated in Fig. 20,
the non-
corrugated portion 140D occupies approximately two thirds of the length of the
middle
portion 140A, and the corrugated portion 141D occupies approximately a third
of the
length of the of the middle portion 140A. However, this is not obligatory and
other
different length relationship between the corrugated portion and the non-
corrugated
portion of the middle portion 140A are also possible.
Turning to Fig. 21, the corrugated balloon 150 includes a middle potion 150A,
a
proximal side portion 150B and a distal side portion 150C. The proximal side
portion
150B is identical to the proximal portion 40B (of Fig. 13) and comprises
contiguous
portions 150H, 150G and 150F. The distal side portion 150C is identical to the
distal
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portion 50C (of Fig. 16) and includes a corrugated dome-like portion 1501 and
a non-
corrugated cylindrical portion 150J similar to the portions 501 and 50J,
respectively, of
Fig. 16. However, the middle portion 140A comprises a single non-corrugated
portion.
Thus, while the middle portion 150A does not have an extended surface area as
do other
corrugated middle portions described herein, the balloon 150 has the advantage
of
facilitated folding of the distal portion 150C of the balloon 150 during the
intussuscepting of the balloon 150 because the corrugations of the portion
1501.
Thus, it is noted that in balloon catheters in which at least part of the
distal portion is
corrugated, the force required for causing collapse of the distal portion of
the balloon is
substantially smaller than the force required to cause collapse of the
proximal portion of
the balloon. Similarly for the same mechanical reasons, in balloon catheters
in which at
least part of the distal portion and at least the distal part of the middle
portion are
corrugated, the force required for causing collapse of the distal portion of
the balloon is
substantially smaller than the force required to cause collapse of the
proximal portion of
the balloon. Such balloons have the advantage of increasing the probability of
collapse
of the distal part or portion of the corrugated balloon upon pulling the inner
tube 17
proximally within the outer tube 17 (see Fig. 3).
It is also noted that while preferably, the proximal portion of the balloons
described
herein and illustrated in the drawings are not corrugated (in order to
minimize the
probability of initial collapse of the proximal portion of the balloon when
the inner tube
17 is pulled proximally), it is possible to construct and use embodiments of
balloon
catheters having balloons having a corrugated proximal part and balloon
catheters having
the entire balloon being corrugated (continuously or alternatingly as shown in
the
example of Fig. 25 hereinbelow). For example, in accordance with other
embodiments
of the balloon catheters of the present application, if the balloon is made to
have a
corrugated proximal part or to be corrugated along the entire balloon length,
the
probability of the proximal collapse of the balloon when the inner tube 17 is
pulled
proximally may be substantially reduced by making the walls of the proximal
part of the
balloon thicker than the walls of the middle and/or distal parts of the same
balloon. This
will enable the use of such balloons safely and effectively while allowing a
greater part
of the balloon to be corrugated.
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It is further noted that typically (but not obligatorily), the balloon
catheters of the
present application may have a substantially cylindrical middle portion
flanked by a
distally extending portion and a proximally extending portion. The diameter of
the
distally extending portion typically diminishes in the distal direction and
the diameter of
the proximally extending portion typically diminishes in the proximal
direction. The
change of the diameter of the distal and/or proximal balloon portions may be
gradual (as
in a conical shape or dome shape but may also be non-gradual or at least
partially non-
gradual by diminishing abruptly ( as in the form of a step or a step or an
abrupt transition
between a first cone angle to a steeper cone angle). Additionally the balloons
of the
present application maybe non-linearly tapered in their proximal and/or distal
portions by
having outwardly or inwardly curving cross sectional shapes of the proximal
and/or
distal portions.
Reference is now made to Figs. 22-25 which are schematic cross-sectional
diagrams
illustrating parts of corrugated balloons having different additional types of
folds or
corrugation shapes and/or having multiple corrugated portions interspersed
with non-
corrugated portions, in accordance with additional embodiments of corrugated
balloons
of the present application.
It is noted that in all of the drawings of Figs. 22-25, the reference numeral
P
schematically represents the proximal side and the reference numeral D
schematically
represents the distal side of the balloon.
Turning to Fig. 22, the corrugated portion of the balloon 160 (only part of
which is
illustrated in Fig. 22) includes multiple corrugations 160N. Each one of the
multiple
corrugations 160N has a straight part 160Q facing towards the proximal side of
the
balloon 160 and a curved part 160R facing the distal side of the balloon 160.
Turning to Fig. 23, the corrugated portion of the balloon 170 (only part of
which is
illustrated in Fig. 23) includes multiple corrugations 170N. Each one of the
multiple
corrugations 170N has a straight part 170Q facing towards the distal side of
the balloon
170 and a curved part 170R facing the proximal side of the balloon 170.
Turning to Fig. 24, the corrugated portion of the balloon 180 (only part of
which is
illustrated in Fig. 24) includes multiple symmetrical corrugations 180N. Each
one of the
multiple corrugations 180N has a first curved part 180Q facing towards the
proximal
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side of the balloon 180 and a second curved part 180R facing the distal side
of the
balloon 180.
Turning to Fig. 25, the balloon 190 (only part of which is illustrated in Fig.
25)
includes three corrugated portions 190A, 190B and 190C and non-corrugated
portions
190D, 190E and 190F. It is noted that in accordance with embodiments of the
corrugated balloons disclosed herein, the balloons may include any practical
number of
corrugated portions interspersed by non-corrugated portions. Furthermore,
while the
type, shape and dimensions of the corrugations in the portions 190A, 190B and
190C in
the non-limiting example illustrated in Fig. 25 are identical, this is by no
means
obligatory and in different embodiments of balloons with multiple corrugated
portions,
each portion may have a different type of corrugation in which one or more
parameters
of the corrugation's shape, dimensions, may be varied at will.
Moreover, different types and/or sizes and/or shapes of corrugations may be
mixed
and matched within each corrugated portion of the balloons of the present
application.
Turning now to Fig. 26 which is a schematic cross sectional diagram
illustrating part
of the wall of a corrugated balloon having alternating types of differently
shaped
corrugations, the wall of the balloon 200 (only part of which is shown in Fig.
26)
includes triangular shaped corrugations 200N interspersed with curved
corrugations
200R.
Generally, in the mixed corrugation type balloons of the present application,
any
types and sizes of corrugations may be used mixed and matched as desired. For
example, the balloon 200 of Fig. 26 may be modified to have repeated sequences
of
corrugations having a single triangular corrugation 200N followed by two
curved
corrugations 200R and this sequence may be repeated along the entire length of
the
corrugated portion. Furthermore, any desired type of repeating or non-
repeating
combinations and sequences of two or more different corrugation types may be
used in
the corrugated balloons of the present application.
It is further noted that the cylindrical portions 10J, 34J, 35J, 36J, 37J,
40J, 45J, 47J,
50J, 60J, 70J, 80J, 140J, and 150J are also referred to as the "distal
margins" of the
balloons 10, 34, 35, 36, 37, 40, 45, 47, 50, 60, 70, 80, 140, and 150,
respectively,
throughout the specification and the claims of the present application.
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Similarly, it is also noted that the cylindrical portions 10H, 34H, 35H, 36H,
37H,
40H, 45H, 47H, 50H, 60H, 70H, 80H, 140H, and 150H and are also referred to as
the
"proximal margins" of the balloons 10, 34, 35, 36, 37, 40, 45, 47, 50, 60, 70,
80, 140,
and 150, respectively, throughout the specification and the claims of the
present
application.
It is noted that the side portion(s) of the corrugated balloons of the present
application may have cylindrical and/or conical and/or frusto-conical, and/or
rounded
truncated dome-like and/or tapering shape(s). The side portion(s) may also
have a shape
which is a combination of one or more of cylindrical, conical, frusto-conical,
dome-like
and tapering shapes. These shapes are not intended to be limiting, and other
different
types of portion shapes may also be used in implementing the corrugated
balloons of the
present application.
The corrugated balloon catheters of the present application may use sleeve
like
elements having various different dimensions. Typically (but not
obligatorily), the
inflated diameter of the corrugated balloon may be in the range of 1.5 - 35
millimeter and
the length of the corrugated balloons may be in the range of 5- 300
millimeter, with all
possible combinations of balloon length and balloon diameters within these
ranges may
be used. In accordance with some typical non-limiting examples, a balloon with
a length
of 15 millimeter may have an inflated diameter of 3 millimeters and a balloon
with a
length of 250 millimeters may have an inflated diameter of 12 millimeter. The
typical
(but non-limiting) range of balloon wall thickness is 0.022 - 0.030 millimeter
depending,
inter alia, on the balloon dimensions and on the application. It will be
appreciated by
those skilled in the art that the above dimension ranges and ratios of balloon
diameter to
balloon length are not obligatory and that other different dimensions and
ratios extending
beyond the above indicated ranges may be used in implementing the catheters,
depending, inter a/ia, on the particular application.
While it is possible for the corrugations to span the entire inflatable length
of the
balloons, as disclosed herein, typically, in some preferred embodiments only
the distal
portion of the balloon is corrugated and in some other preferred embodiments,
both the
distal balloon portion and part of the balloon middle portion are corrugated.
Typically,
in these embodiments between a fifth (1/5) and a third (1/3) of the total
length of the
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balloon are corrugated. However, shorter or longer portions of the balloon
length may be
corrugated, depending, inter alia, on the balloon structure and shape, the
balloon's wall
thickness (and/or on the balloon's wall thickness gradient in balloons with a
non-uniform
wall thickness), and on the particular application.
Returning to Fig. 2, with respect to the dimensions of the corrugations, the
corrugations span a "peak to valley" amplitude L (defined as the difference
between the
maximal radial distance of the corrugation and the minimal radial distance of
the
corrugation as measured from the longitudinal axis of the inflated balloon,
irrespective of
the precise corrugation shape). Typically, the corrugation amplitude L depends
on the
diameter of the balloon. Preferably, the corrugation amplitude L is in the
range of 2.5%
- 20% of the inflated balloon diameter. However, other values of the
corrugation
amplitude L may also be used which are larger or smaller than this range
depending,
inter alia, on the balloon wall thickness and on the particular shape of the
corrugations.
The corrugation pitch P is defined as the distance between adjacent peaks of
the
corrugations (see Fig. 2 for an indication of P in the particular case of
symmetrical
triangularly shaped corrugations of the balloon 10), and may depend, inter
alia, on the
outer diameter of the inflated balloon and on the type and shape of the
corrugations.
In accordance with one typical non-limiting example, in a balloon having a
length of
15 millimeter and an inflated outer diameter of 3 millimeter, the corrugation
pitch P may,
preferably (but not obligatorily) be in the range of 0.025-1.8 millimeter. In
accordance
with another typical non-limiting example, in a balloon having a length of 250
millimeter and an inflated outer diameter of 12 millimeter, the corrugation
pitch P may
preferably (but not obligatorily) be in the range of 0.1 - 7.2 millimeter. It
will be
appreciated by those skilled in the art that the above two examples are given
by way of
example only and are not intended to be limiting, and that other values of the
corrugation
pitch P which are higher or lower than the corrugation pitch ranges of the
above given
examples may be used depending, inter alia, on the particular values of the
balloon
length, balloon diameter, balloon wall thickness, corrugation shape and other
design and
manufacturing considerations.
Finally, it is noted that while the particular exemplary catheter illustrated
in Fig. 3
discloses use of the corrugated balloons of the present application in an
"over the wire"
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catheter configuration, the corrugated balloons described herein may also be
used in
conjunction with other different types of catheters, as is known in the art.
For example,
the corrugated balloons described herein may also be used in the rapid
exchange
catheters disclosed in Published International Patent applications,
Publication Number
WO 2007/042935, or in other catheter systems having intussuscepting balloons,
such as
the catheters disclosed in Published International Patent applications,
Publication
Numbers. W02005/102184, W02007/004221, W02008/004238 and W02008/004239.
20
30
37
