U.S. patent application number 12/427254 was filed with the patent office on 2009-11-12 for system and method for transluminal access.
This patent application is currently assigned to XLumena, Inc.. Invention is credited to Michael P. Allen, Kenneth F. Binmoeller, Fiona M. Sander.
Application Number | 20090281379 12/427254 |
Document ID | / |
Family ID | 41267407 |
Filed Date | 2009-11-12 |
United States Patent
Application |
20090281379 |
Kind Code |
A1 |
Binmoeller; Kenneth F. ; et
al. |
November 12, 2009 |
SYSTEM AND METHOD FOR TRANSLUMINAL ACCESS
Abstract
A translumenal access system includes a translumenal access
catheter, a trocar, and one or more guidewires. The trocar may be
introduced through adjacent tissue layers, typically from an
endoscope, and the translumenal access catheter introduced through
the resulting penetration over the trocar. A balloon on the
catheter may be used to dilate the penetration, and an enlarged
distal portion of the balloon may be used to draw the tissue layers
into apposition. The first stent may be exchanged for the trocar
and a second stent may be introduced through a side port on the
access catheter. The stents may be then used to introduced
catheters or other interventional tools, optionally for delivering
one or more stents to the enlarged tissue penetration.
Inventors: |
Binmoeller; Kenneth F.;
(Rancho Santa Fe, CA) ; Sander; Fiona M.; (Los
Altos Hills, CA) ; Allen; Michael P.; (Los Altos,
CA) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP
TWO EMBARCADERO CENTER, EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
XLumena, Inc.
Mountain View
CA
|
Family ID: |
41267407 |
Appl. No.: |
12/427254 |
Filed: |
April 21, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61052460 |
May 12, 2008 |
|
|
|
Current U.S.
Class: |
600/106 ;
604/96.01; 606/41; 623/1.11 |
Current CPC
Class: |
A61B 2017/1103 20130101;
A61B 17/11 20130101; A61B 2017/00278 20130101; A61B 17/3468
20130101; A61B 2017/3486 20130101; A61B 17/3478 20130101; A61F 2/82
20130101; A61B 2017/1139 20130101; A61M 2025/09125 20130101; A61B
17/1114 20130101; A61B 2017/00867 20130101; A61M 25/1002 20130101;
A61M 2025/1059 20130101; A61B 2017/00004 20130101; A61B 2017/0034
20130101; A61M 2025/0096 20130101; A61B 17/12009 20130101 |
Class at
Publication: |
600/106 ;
604/96.01; 623/1.11; 606/41 |
International
Class: |
A61M 29/02 20060101
A61M029/02; A61F 2/84 20060101 A61F002/84; A61B 1/018 20060101
A61B001/018; A61B 18/18 20060101 A61B018/18 |
Claims
1. A method for positioning two guidewires between a first body
lumen and a second body lumen, said method comprising: advancing a
tissue penetrating tool from the first body lumen into the second
body lumen to form a passage through the luminal walls; advancing a
balloon catheter over the trocar to position a dilation balloon
within the passage; inflating the balloon to dilate the passage;
exchanging a first guidewire for the tool; advancing the catheter
further into the second body lumen so that a side wire port on the
catheter proximal of the balloon is within the second body lumen;
advancing a second guidewire through the side port into the second
body lumen; and withdrawing the balloon catheter to leave the first
and second guidewires in place through the dilated passage.
2. A method as in claim 1, further comprising advancing a first
stent placement catheter over the first guidewire and placing a
first stent in the dilated passage.
3. A method as in claim 1, wherein the first body lumen is selected
from the group consisting of the esophagus, the stomach, the
duodenum, the small intestines and the large intestines and the
second body lumen or structure is selected from the group
consisting of a bile duct, a gallbladder, a pancreas, a pancreatic
duct, a pancreatic pseudocyst, a urinary bladder, and a liver.
4. A method as in claim 2, further comprising advancing a second
stent placement catheter over the second guidewire and placing a
second stent in the dilated passage adjacent to the first
stent.
5. A method as in claim 3, wherein the first body lumen is a
stomach and the second body lumen is a pseudocyst.
6. A method for dilating a tissue passage between a first body
lumen and a second body lumen or structure, said method comprising:
advancing a tissue penetrating tool from the first body lumen into
the second body lumen to form a passage through the luminal walls;
advancing a balloon catheter over the tool to position a distal
portion of a dilation balloon beyond the passage to within the
second body lumen or structure; inflating said distal portion of
the balloon beyond the passage while a proximal portion of the
balloon remains uninflated; tensioning the balloon catheter
proximally so that said inflated distal portion of the balloon
engages the wall of the second body lumen and draws the second wall
against the first wall to place said walls in apposition; and
inflating the proximal portion of the balloon to dilate the passage
through the tissue layers.
7. A method as in claim 6, wherein the first body lumen is selected
from the group consisting of the esophagus, the stomach, the
duodenum, the small intestines and the large intestines and the
second body lumen or structure is selected from the group
consisting of a bile duct, a gallbladder, a pancreas, a pancreatic
duct, a pancreatic pseudocyst, a urinary bladder, and a liver.
8. A method as in claim 6, further comprising exchanging the trocar
for a guidewire.
9. A method as in claim 8, further comprising advancing a stent
placement catheter over the guidewire and placing a stent in the
dilated passage.
10. A translumenal access system comprising: a first guidewire; a
second guidewire; a tissue penetrating tool; and a translumenal
access catheter including: (a) a catheter body having a proximal
end, a distal end, a central lumen and a side lumen; and (b) a
dilation balloon on the catheter body near the distal end; wherein
the central lumen extends from the proximal to the distal end of
the catheter body and exchangeably receives the tool and the first
guidewire and wherein the side lumen extends from the proximal end
of the catheter body to a location immediately proximal of the
dilation balloon and removably receives the second guidewire.
11. A system as in claim 10, wherein the catheter further includes
(c) a handle assembly attachable to the proximal end of the
catheter body, wherein the handle is configured to lock to an
endoscope when the catheter body is within a working channel of the
endoscope.
12. A system as in claim 11, wherein the handle comprises an inner
core which couples to the catheter body and an outer grip which
couples to the tool, wherein a user can advance and retract the
grip relative to the inner core to advance and retract the tool
relative to the catheter body.
13. A system as in claim 12, further comprising a catheter body
adjustment mechanism movably positioned in the inner core to
axially advance and retract the catheter body relative to the inner
core, outer grip, and the tool.
14. A system as in claim 13, further comprising a tool depth
adjustment mechanism on the catheter body to limit the distal
motion of the outer grip and the tool puncture depth.
15. A system as in claim 13, further comprising a tool looking
mechanism on the outer grip to holder the outer grip and tool in a
fixed position relative to the inner core.
16. A catheter and penetrating tool assembly comprising: a catheter
body having a proximal end, and distal end, and a central lumen; a
tissue penetrating tool slidably disposed in the central lumen,
said tool having a tissue-penetrating distal end; and a handle
attachable to the proximal end of the catheter body, said handle
including an inner core with a catheter advancement mechanism which
couples to the catheter body and an outer grip which couples to the
tool, wherein a user can advance and retract the grip relative to
the inner core to advance and retract the tool relative to the
catheter body.
17. An assembly as in claim 16, further comprising a catheter body
adjust mechanism on the inner core to axially advance and retract
the catheter body relative to the handle and the tool.
18. An assembly as in claim 17, further comprising a tool
adjustment mechanism on the outer grip to axially advance and
retract the tool relative to the handle and the catheter body.
19. An assembly as in claim 16, wherein the tissue penetrating tool
comprises a trocar.
20. An assembly as in claim 16, wherein the tissue penetrating tool
has an electrosurgical tip which permits radiofrequency current
assisted tissue penetration.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of provisional
application No. 61/052,460 (Attorney Docket No. 026923-000700US),
filed on May 12, 2008, the full disclosure of which is incorporated
herein by reference. The disclosure of the application also relates
to those of commonly owned application Ser. No. 11/886,499
(Attorney Docket No. 026923-000410US), filed on Sep. 14, 2007; and
Ser. No. 12/______ (Attorney Docket No. 026923-000710US), filed on
the same day as the present application.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to medical methods
and devices. In particular, the present invention relates to
catheters and other tools for providing access and placing
guidewires between adjacent body lumens.
[0004] A number of endoscopic and other intraluminal procedures
require remote access from one body lumen into an adjacent body
lumen. For example, a number of procedures may be performed by
entering the gastrointestinal (GI) tract, particularly the
esophagus, stomach, duodenum, small intestine, or large intestine,
and passing tools from the GI tract into adjacent organs and
structures, such as the bile duct, the pancreatic duct, the gall
bladder, the pancreas, cysts, pseudocysts, abscesses, and the like.
Such access into the adjacent body lumen will usually require
forming a penetration or other access hole from within the first
body lumen, through a wall of the first body lumen, through a wall
of the second body lumen, and into the interior of the second body
lumen. Depending on the procedure being performed, catheters or
other tools will usually be advanced through the penetration for
stent placement, drainage tube placement, or the like.
[0005] As with many medical access procedures, it is desirable that
the catheters and other access tools be introduced over a guidewire
when advanced through the luminal wall penetration. Additionally,
it is often desirable that the luminal wall penetrations be dilated
prior to stent placement or other interventional procedure. Such
dilation can be problematic as the luminal walls will not
necessarily be in close apposition, particularly after penetration
and access formation, thus making positioning of a dilation balloon
difficult. A further challenge arises from the need to employ
multiple tools for forming the initial access penetration, dilating
the penetration, placing one or more guidewires, and subsequently
placing the stents or performing other interventional
procedures.
[0006] It would be desirable to be able to provide methods and
systems for creating translumenal access passages with the ability
to dilate the passages and place one or more guidewires through the
passage. It would be particularly desirable to reduce the number of
tools and method steps needed for such protocols. At least some of
these objectives will be met by the inventions described and
claimed below.
[0007] 2. Description of the Background Art
[0008] US 2003/069533 describes an endoscopic transduodenal biliary
drainage system which is introduced through a penetration, made by
a trans-orally advanced catheter having a needle which is advanced
from the duodenum into the gall bladder. U.S. Pat. No. 6,620,122
describes a system for placing a self-expanding stent from the
stomach into a pseudocyst using a needle and an endoscope. US
2005/0228413, commonly assigned with the present application,
describes a tissue-penetrating device for endoscopy or
endosonography-guided (ultrasonic) procedures where an anchor may
be placed to form an anastomosis between body lumens, including the
intestine, stomach, and gallbladder. See also U.S. Pat. No.
5,458,131; U.S. Pat. No. 5,495,851; U.S. Pat. No. 5,944,738; U.S.
Pat. No. 6,007,522; U.S. Pat. No. 6,231,587; U.S. Pat. No.
6,655,386; U.S. Pat. No. 7,273,451; U.S. Pat. No. 7,309,341; US
2004/0243122; US 2004/0249985; US 2007/0123917; WO 2006/062996; EP
1314404 Kahaleh et al. (2006) Gastrointestinal Endoscopy 64:52-59;
and Kwan et al. (2007) Gastrointestinal Endoscopy 66:582-586.
Shaped balloons having differently sized segments and segments with
staged opening pressures are described in U.S. Pat. Nos. 6,835,189;
6,488,653; 6,290,485; 6,022,359; 5,843,116; 5,620,457; 4,990,139;
and 3,970,090.
BRIEF SUMMARY OF THE INVENTION
[0009] The present invention provides improved methods and systems
for establishing translumenal access between a first body lumen and
a second body lumen. Such translumenal access may be intended for
any medical purpose but will usually be intended for performing
translumenal therapeutic endoscopy where the first body lumen is
typically within the gastrointestinal (GI) tract, including the
esophagus, the stomach, the duodenum, the small intestines, and the
large intestines. The second body lumen will typically be an organ
or other tissue structure which lies adjacent the gastrointestinal
tract, including the bile duct, the pancreatic duct, the gall
bladder, cysts, pseudocysts, abscesses, the pancreas, a pancreatic
pseudocyst, the liver, the urinary bladder, and the like. Exemplary
medical procedures will typically involve initially establishing a
translumenal access tract, typically by penetrating a trocar or
other sharpened instrument from an endoscope. The procedures may
also involve placing one or more guidewires which are useful for
advancing one or more catheters into the translumenal access tract.
The exemplary procedures may also include dilating the translumenal
access tract, typically before placing guidewire(s) or performing
other therapeutic or diagnostic procedures.
[0010] The methods and systems of the present invention provide a
number of advantages over previous access protocols and techniques.
In particular, the present invention provides an integrated device
which can be advanced over a trocar or other penetrating tool which
has been delivered from an endoscope to form the initial tissue
penetration. The integrated access device will typically perform
one or more additional functions to simplify the access protocol as
well as facilitate subsequent therapeutic protocols. For example,
the access device may be used for the controlled advancement of the
trocar or other penetrating tool in order to form the initial
tissue penetration. The access device may also incorporate a
dilation balloon which allows the luminal penetrations to be
dilated without the need to exchange access devices. The balloon or
other expansible member on the access device may also be adapted to
provide for improved luminal wall apposition as well as for
enhanced positioning of the balloon prior to dilation.
Additionally, the access device may provide for the placement of
two or more guidewires within the intraluminal penetration which
facilitates the advancement of separate catheters or other
interventional or diagnostic tools.
[0011] In a first aspect, the present invention provides methods
for positioning two or more guidewires between a first body lumen
and a second body lumen. A trocar is advanced from the first body
lumen into the second body lumen to form a passage through the
luminal walls. A balloon catheter is then advanced over the trocar
to position a dilation balloon within the passage. The balloon is
inflated to dilate the passage, and a first guidewire is exchanged
for the trocar. The trocar-guidewire exchange can be carried out
either before or after the balloon dilation. The catheter is then
further advanced over the first guidewire or trocar into the second
body lumen so that a side port on the catheter located proximal of
the balloon enters into the second body lumen. A second guidewire
is then advanced through the side port into the second body lumen,
and the balloon catheter may then be withdrawn to leave the first
and second guidewires in place through the dilated passage.
[0012] Once in place, the first and second guidewires, and
optionally additional guidewires if further side ports were
provided on the access catheter, may be utilized for any desired
therapeutic or diagnostic procedure. Typically, the guidewires will
be utilized for advancing therapeutic or diagnostic catheters,
often for stent placement to establish a drainage path between the
body lumens. In a specific procedure, the guidewires can be used to
place a pair of stents in order to drain a cyst, pseudocyst or
abscess into the stomach or duodenum.
[0013] In a second aspect, the present invention provides a method
for forming, dilating, and optionally positioning at least one
guidewire between a first body lumen and a second body lumen,
organ, or structure. A trocar is advanced from the first body lumen
into the second body lumen or structure to form a passage through
the luminal walls. A balloon catheter is advanced over the trocar
to position a distal portion of a dilation balloon is positioned
beyond the passage so that said distal portion lies within the
second body lumen or structure. The distal portion of the balloon
is then inflated while a proximal portion of the balloon remains
uninflated (or inflated to a lesser extent), and the balloon
catheter is pulled or otherwise tensioned proximally so that the
inflated distal portion of the balloon engages the wall of the
second body lumen and draws the second luminal wall against the
first luminal wall to place said walls in apposition. The proximal
portion of the balloon may then be inflated to dilate the tissue
members. It is a particular advantage that the inflated distal
portion of the balloon both draws the tissue layers into close
apposition and optimally positions the proximal portion of the
balloon for dilation.
[0014] The dilated passage may then be treated by introducing
further catheters or tools. Typically, the trocar will be exchanged
with a guidewire, and a second guidewire may optionally be advance
through a side port (as described above with respect to the first
aspect of the present invention), either before or after balloon
dilation of the passage. A treatment, diagnostic, or other catheter
may then be introduced over the guidewire. For example, the
treatment catheter may be used to place a stent into the dilated
passage for drainage or for other purposes.
[0015] In a third aspect, the present invention provides a
translumenal access system, which comprises a first guidewire, a
second guidewire, a trocar, and a translumenal access catheter. The
translumenal access catheter includes a catheter body having a
proximal end, a distal end, a central lumen, and a side port and
lumen. A dilation balloon is disposed on the catheter body at or
near the distal end, and the central lumen extends from the
proximal end to the distal end so that it can exchangably receive
the trocar and the first guidewire. The side wire lumen extends
from the proximal end of the catheter body of the side port which
is located immediately proximal of the dilation balloon, and the
side wire lumen removably receives the second guidewire. The
translumenal access system is particularly suited for performing
the methods for placement of two guidewires previously
described.
[0016] The translumenal access system will usually further include
a handle assembly attachable to the proximal end of the catheter,
where the handle is configured to lock to or within an endoscope
when the catheter body is within a working channel of the
endoscope. The handle comprises an inner core which couples to the
catheter body and an outer grip which couples to the trocar. The
inner core comprises a catheter adjustment mechanism that is
movable with respect to the inner core, said catheter adjustment
mechanism typically being attached at its distal end to the
catheter. A control knob or slide mechanism is usually part of the
adjustment mechanism which controls the movement of the catheter.
Thus, using the handle, a user can advance and retract the grip
relative to the inner core to thereby advance and retract the
trocar relative to the catheter body. Further, a user can rotate
the control knob in a clockwise or counterclockwise direction or
advance the slide mechanism in a proximal or distal direction to
thereby advance and retract the catheter relative to the inner core
and the trocar. In this way, after the endoscope has been used to
locate a target location on a body lumen, the translumenal access
catheter may be introduced through the working channel of the
endoscope so that its distal end is adjacent the target location on
the body wall. The trocar will be axially retracted during the
initial positioning. Once the distal end of the access catheter is
properly located, the catheter can be locked relative to the
endoscope and the outer grip can then be rapidly advanced (thrust
forward) to penetrate the trocar through the luminal walls while
the catheter body remains fixed relative to the endoscope. Such
rapid advancement of the trocar is particularly advantageous in
penetrating relatively loose or flaccid luminal walls which might
otherwise resist penetration.
[0017] In preferred aspects, the handle assembly will comprise a
catheter body adjustment mechanism on the inner core, where the
adjustment mechanism permits axial advancement and retraction of
the catheter body relative to the handle and the trocar. Thus, once
the trocar has penetrated the luminal walls, the catheter body may
be advanced over the trocar while the trocar and endoscope remain
stationary. The handle assembly will also preferably include a
trocar depth adjustment mechanism on the inner core, positioned
immediately distal to the outer grip and a trocar lock mechanism
located on the outer grip. The trocar depth adjustment mechanism
allows the maximum depth position of the trocar to be set prior to
trocar advancement and the trocar lock mechanism allows the trocar
to be locked to the central member which is locked to the endoscope
during operation. The trocar depth adjustment mechanism is
particularly useful since it prevents over extension of the trocar
and inadvertent tissue damage. The trocar lock is useful since it
secures the trocar position, prior to advancement, thus eliminating
unintentional damage to the scope or tissue, and after advancement,
secures the trocar in place with respect to the catheter and the
target lumen. The trocar can be precisely positioned immediately
adjacent to the luminal walls prior to advancement by slowly moving
the outer grip forward until the desired position is reached. The
trocar can then be locked in place using the trocar lock mechanism,
or released prior to trocar advancement.
[0018] In a fourth aspect, the present invention provides a
catheter and trocar assembly comprising a catheter body, a trocar,
and a handle attachable to the proximal end of the catheter body.
The trocar is slidably disposed in a central lumen of the catheter
body and has a tissue-penetrating distal end. The handle has an
inner core and an outer grip, generally as described above, which
allows the trocar to be advanced relative to the catheter body
while the inner core remains fixed to the catheter body. The handle
of the catheter and trocar assembly preferably further comprises a
catheter body adjustment mechanism and a trocar adjustment
mechanism, again as described previously in connection with the
systems of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 illustrates a system according to the present
invention comprising a translumenal access catheter, a trocar, and
a pair of guidewires.
[0020] FIG. 2 is a detailed view of the distal end of the
translumenal access catheter of the system of FIG. 1.
[0021] FIG. 3A is a detailed view of the translumenal access
catheter of FIG. 1, similar to that shown in FIG. 2, with the
dilation balloon fully inflated and a pair of guidewires in
place.
[0022] FIG. 3B is a detailed view of the translumenal access
catheter of FIG. 1, similar to that shown in FIG. 2, with the
anchor balloon fully inflated inside of the fully inflated dilation
balloon, and a guidewire in place in the proximal location.
[0023] FIG. 4 is a cross-sectional view of the translumenal access
catheter taken along line 4-4 of FIG. 2.
[0024] FIG. 5 is a cross-sectional view of the translumenal access
catheter taken along line 5-5 of FIG. 2.
[0025] FIG. 6 is a cross-sectional view of the translumenal access
catheter taken along line 6-6 of FIG. 2.
[0026] FIG. 7 is a cross-sectional view of the translumenal access
catheter taken along line 7-7 of FIG. 2.
[0027] FIGS. 8A and 8B illustrate an exemplary handle construction
for the translumenal access catheter shown with a grip in its fully
proximal configuration (FIG. 7A) and the grip in its fully distal
configuration (FIG. 7B).
[0028] FIG. 8C is a proximal end view of the handle of FIGS. 7A and
7B.
[0029] FIG. 9 illustrates a first embodiment of a trocar useful in
the systems and methods of the present invention.
[0030] FIG. 10 illustrates a second trocar construction useful in
the systems and methods of the present invention.
[0031] FIG. 11A illustrates a first embodiment of a trocar with a
faceted solid trocar tip
[0032] FIG. 11B illustrates a second embodiment of a trocar with a
chamfered hollow tip
[0033] FIGS. 12A-12K illustrate a method according to the present
invention for positioning two catheters within a tissue penetration
between adjacent body lumens and for deploying a pair of parallel
stents within the tissue penetration.
[0034] FIGS. 13A-13C illustrate a modification to the method of
FIGS. 10A-10I for placing a single guidewire and a single
stent.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Referring to FIG. 1, a translumenal access system according
to the present invention comprises a translumenal access catheter
10, a trocar 12, and one or more guidewires 14 usually including at
least two guidewires. The translumenal access catheter 10 comprises
a catheter body 18 having a distal end 20 and a proximal end 22. An
inflatable balloon 24 is located near the distal end 20 of the
catheter body 18 and is shown in its radially conformed or deflated
configuration in FIGS. 1 and 2 and in its radially expanded or
inflated configuration in FIG. 3.
[0036] While in some instances, balloon 24 may inflate to a
cylindrical, spherical, tapered, or other more conventional balloon
configuration, it is preferred that the balloon 24 have a distal
portion 26 which inflates to a larger diameter than does a proximal
portion 28. It is also preferred that distal portion of balloon 24
inflate first, while proximal portion 28 remains substantially
uninflated until infation of the distal portion is substantially
completed. The advantages of this configuration are described in
more detail in connection with the method of the present invention
with reference to FIGS. 12D-12F below.
[0037] As shown in the cross-sectional view of FIG. 4, the catheter
body 18 includes at least a central lumen 30, a guidewire lumen 32,
a balloon inflation lumen 34 and optionally a second balloon
inflation lumen 35, through its proximal portion. As illustrated in
FIG. 3A, the guidewire lumen 32 terminates in a side port 36 which
permits a guidewire 14 to be advanced from the guidewire lumen 32
at a location proximal to the balloon. As illustrated in
cross-sectional view FIG. 5 & FIG. 6, the central lumen 30 and
balloon inflation lumens 34 and 35 continue to the balloon region,
with the balloon inflation lumen(s) terminating to deliver
inflation media within the balloon (not shown). The central lumen
30 continues all the way to the distal end 20 of the catheter body
where it terminates in a port 38 through which the trocar 12 and
subsequently a second guidewire 14 can extend, as illustrated in
FIG. 3A and cross section FIG. 7.
[0038] Catheter body 18 will typically be formed as an extruded
polymer, where suitable polymers include polyether block
amide_(Pebax.RTM.), nylon, polyethylene and the like. The lumens
may be formed during extrusion and/or by forming over mandrels in a
conventional manner or the lumens may be formed from individual
tubes that are held together with an outer tubular liner which may
be heated to fuse and/or shrink to hold the tubes in close
apposition. The length of the catheter body 18 will vary depending
on the intended use, but will typically be in the range from 50 cm
to 250 cm, more usually being in the range from 100 cm to 200 cm.
The guidewire lumens will be sized to receive conventional
guidewires, typically up to an 0.035 inch wire, but could be
smaller or larger, depending on the intended use. The central lumen
will be large enough to receive the trocar as well as a guidewire,
typically having a diameter in the range from 0.01 inch to 0.1
inch. Typically, the balloon will have a length in the range from 1
cm to 8 cm and a diameter in the range from 5 mm to 25 mm.
[0039] The balloon will typically be formed from a non-distensible
polymer, such as polyethyleneterephthalate (PET), polyethylene (PE)
or nylon, or may be formed from a distensible polymer such as
polyurethane, polyether block amide (Pebax.RTM.) or silicone, and
will be heat treated or otherwise formed to have the desired
geometry. As will be explained in more detail later, the balloon
may comprise a single internal chamber, where the enlarged distal
portion inflates fully at a first pressure, typically in the range
from above 1 atm. to 4 atm., while the proximal portion inflates at
a higher pressure, typically in the range from 6 atm. to 12 atm.
Thus, a staged inflation of the balloon can be performed during the
procedure where the distal portion is first inflated to its full
diameter and the proximal portion is only later inflated to the
lesser diameter. Alternatively, single or multiple balloons may be
configured with different inflatable compartments and separate
inflation lumens so that a larger distal portion can be inflated
prior to the smaller proximal portion. One such balloon
configuration includes an outer non-distensible balloon, including
a larger distal portion 26 and a smaller proximal portion 28, and
an inner distensible balloon 27, positioned distally coincident
with the larger distal portion of the outer balloon as in FIG. 3B.
Inflation lumen 34, for the outer balloon 24, and inflation lumen
35 for the inner balloon 27 are also shown in FIG. 3B. Methods for
fabricating such shaped, staged-inflation balloons are well
described in the technical and patent literature. See, for example,
U.S. Pat. Nos. 6,835,189; 6,488,653; 6,290,485; 6,022,359;
5,843,116; 5,620,457; 4,990,139; and 3,970,090, the full
disclosures of which are incorporated herein by reference.
[0040] A handle assembly 40, as illustrated in FIG. 8A-8C, is
secured to the proximal end 22 of the catheter body 18, as best
seen in FIG. 8A. The handle assembly 40 includes both an inner core
42 and an outer grip 44, where the grip 44 can be axially advanced
and retracted over the inner core between a proximally disposed
position, as shown in FIG. 8A, to a distally disposed position, as
shown in FIG. 8B. The outer grip can be locked at any position
along inner core 42 using locking mechanism 48. The trocar
penetration depth can set using the trocar depth adjustment
mechanism 49 which slides over the inner core 42 and can be locked
in any position along inner core 42. Trocar depth adjustment
mechanism 49 is shown in solid line in its most proximal position
and in its most distal position in broken line.
[0041] The trocar 12 is received through a port 46 (FIG. 8c) in the
grip 44 of the handle assembly 40 and is constrained to the grip by
a locking mechanism such as a luer lock. The trocar 12 passes into
the central lumen 30 of the catheter body 18 FIG. 4-7), but motion
of the trocar relative to the catheter body is controlled by moving
the grip 44 proximally and distally relative to the inner core 42.
The catheter body 18 is fixedly attached to the catheter adjustment
mechanism of the inner core 42 of the handle assembly 40 so that
the catheter body moves independently from the outer grip and the
trocar. Motion of the catheter body relative to the inner core 42
and the handle assembly 40 as a whole is controlled by a catheter
adjustment mechanism including a control knob 50 or slide mechanism
(not shown).
[0042] The handle assembly 40 will be adapted so that it can be
detachably secured to a proximal end of an endoscope when the
catheter body 18 is within a working channel thereof. Typically, a
distal end 56 of the inner core 42 will be secured to the port of
the working channel of the endoscope. This is typically done using
a locking mechanism such as a luer lock positioned at the proximal
end of the endoscope working channel. Thus, the inner core 42 will
be will be immobilized relative to the endoscope (and usually the
patient), but the trocar can be advanced relative to the endoscope
and the catheter body 18 by moving the outer grip 44 from its
proximal configuration, as shown in FIG. 8A, to a distal position,
as shown in FIG. 8B. This is particularly useful for thrusting the
trocar through tissue as will be described in more detail
hereinbelow. The trocar depth adjustment mechanism 49 can be set at
any point along inner core 42, thus limiting the distal travel
distance of grip 44 and trocar 12.
[0043] Referring to FIGS. 4 & 8C, the handle assembly 40
further includes at least one port or connector 60 for attachment
of an inflation medium to the inflation lumen 34 and optionally a
second inflation port or connector 62 for attachment of an
inflation medium to the inflation lumen 35 of the catheter body 18.
The handle assembly 40 will also include a guidewire port 64 to
allow introduction of a guidewire into the guidewire lumen 32 of
the catheter body 18.
[0044] The present invention can use a wide variety of trocars,
including trocars having actuable blades for enlarging a trocar
penetration, as described in detail in co-pending, commonly-owned
provisional application 61/______ (Attorney Docket No.
026923-001200US), filed on the same day as the present application,
the full disclosure of which is incorporated herein by reference.
It is desirable that the trocar have a relatively flexible distal
portion since it will have to be advanced through central lumen 30
of the catheter body, where the catheter will often be angled or
deflected in order to be directed at the target wall site by the
endoscope. Thus, a first suitable trocar assembly 70 is illustrated
in FIG. 9. Trocar 70 includes a solid core proximal portion having
a reduced diameter distal portion 74 and a tissue-penetrating tip
76. To provide for flexibility yet retain sufficient column
strength to permit tissue penetration, the reduced diameter section
74 will often be covered by a reinforcing coil spring 78.
[0045] An alternative trocar assembly 80, in the form of an open
needle-like structure, is illustrated in FIG. 10. The needle-like
trocar 80 comprises a tubular body 82 which is laser cut or
otherwise formed to have a helically cut region 84 over a portion
near the distal end thereof. The helical cuts provide for
flexibility while maintaining sufficient column strength so that
the chamfered, sharpened end 86 may be advanced through the tissue
layers from the catheter, as described in more detail below. In yet
other trocar assemblies, as shown in FIGS. 11A and 11B, at least a
distal portion of the trocar is made of a flexible memory metal
such as nitinol or elgiloy, shown with a faceted solid trocar tip
90 in FIG. 11A and with a chamfered hollow tip 91 in FIG. 11B.
These materials provide improved flexibility over stainless steel
or other similar metals. Alternately any of the trocar assemblies
previously mentioned (or other conventional tissue penetrating
probes) can be energized with radiofrequency (RF) current to
provide or assist in tissue penetration. The RF current may be
provided by conventional electrocautery power supplies operating in
a cutting mode.
[0046] Referring now to FIGS. 12A-12K, a first translumenal access
method according to the present invention will be described in
detail. As shown in FIG. 12A, an endoscope E may be advanced into
an internal body space, typically in the GI tract, such as the
esophagus, the stomach, the duodenum, the small intestine or the
large intestine, to identify a target location T on a first luminal
wall or other tissue layer TL1. For example, the endoscope E may
include a viewing element 300 (typically an optical fiber or a
small camera) and an illuminating source through a tube (typically
an optical fiber or LED) to permit visualization. The endoscope E
may also include an ultrasound transducer (not shown) positioned at
the distal end near the viewing element 300 to allow endoscopic
ultrasound (EUS). The endoscope E will also include a working
channel 304 which may be used to advance the trocar and the
translumenal access catheter in accordance with the principles of
the present invention.
[0047] As shown in FIG. 12B, a distal end 20 of the access catheter
10 is advanced from the endoscope E so that the distal port 38 is
adjacent the target location T. Once the location is confirmed (for
example by endoscopic ultrasound (EUS)), the outer grip 44 on the
handle assembly 40 may be advanced to thrust the distal end of
trocar 12 forward so that it penetrates the tissue layers TL1 and
TL2, as illustrated in FIG. 12B. The quick advancement of the
trocar 12 helps assure that both layers are penetrated.
[0048] As shown in FIG. 12C, the access catheter 10 can then be
advanced over the trocar 12 so that the distal portion 26 of the
balloon 24 passes fully into the second body lumen while the
proximal portion usually remains at least partially within the
tissue penetrations P. After positioning the balloon 24, the distal
portion 26 is inflated while the proximal portion 28 remains
uninflated (or only partially inflated), as shown in FIG. 12D. The
catheter body 18 may then be drawn proximally, as shown in FIG.
12E, so that the inflated distal portion 26 of the balloon 24
engages the second tissue layer TL2 to apply force to the tissue
layer and to draw layers TL1 and TL2 into apposition. By drawing
the tissue into apposition using the expanded distal portion 26,
the unexpanded proximal portion 28 is positioned within the
passages P which have been formed into the tissue layers TL1 and
TL2. Thus, the uninflated proximal portion 28 of the balloon 24 is
optimally positioned to be expanded to dilate the passages P, as
shown in FIG. 12F. At any time after the balloon catheter 10 is
introduced into the second body lumen, as shown beginning in FIG.
12C, it will be possible to exchange to the trocar 12 for a
guidewire 14, with the exchange being shown in FIG. 12F.
[0049] After the passages P have been dilated, the balloon 24 may
be drawn down (deflated), and the catheter body 18 advanced so that
the side port 36 lies within the second body lumen, as illustrated
in FIG. 12G. The second guidewire 14 may then be advanced into the
second body lumen through side port 36. With both guidewires 14 now
advanced into the second body lumen, the catheter body 18 may be
withdrawn, leaving the two guidewires 14 in place to provide access
from the working channel 304 of the endoscope into the second body
lumen through the enlarged penetrations P, as shown in FIG.
12H.
[0050] With the two guidewires 14 in place, catheters and/or other
therapeutic or working tools may be advanced into the second body
lumen. As illustrated for example in FIG. 12I, when the second body
lumen comprises a pseudocyst, a first catheter C1 may be used to
deliver one or several 5 Fr to 10 Fr plastic straight or pigtail
stent(s) (not shown) or a self-expanding stent S1, as illustrated
in FIG. 12J. Suitable stents and delivery means are described in
commonly-owned, co-pending patent application 12/______ (Attorney
Docket No. 026923-000710US), filed on the same day as the present
application, the full disclosure of which is incorporated herein by
reference. Conveniently, the second guidewire 14 may be used to
deliver a second stent using a second catheter C2, as shown in FIG.
12J. The two deployed stents S1 and S2 present in the enlarged
penetrations P are shown in FIG. 12K.
[0051] Referring now to FIGS. 13A-13C, the methods and systems of
the present invention may also be used to advance a single
guidewire to deploy a single stent or perform other interventional
protocols using a single catheter or tool. When the translumenal
access catheter 10 is in the position shown in FIG. 12F, the
balloon 26 may be deflated and the catheter immediately withdrawn,
leaving only the first guidewire 14 in place, as shown in FIG. 13A.
A catheter C may then be advanced over the single guidewire 14
through the enlarged penetration P, as shown in FIG. 13B, and the
catheter used to deploy a single stent S, as shown in FIG. 13C.
[0052] While the above is a complete description of the preferred
embodiments of the invention, various alternatives, modifications,
and equivalents may be used. Therefore, the above description
should not be taken as limiting the scope of the invention which is
defined by the appended claims.
* * * * *