U.S. patent application number 10/064070 was filed with the patent office on 2004-01-01 for method for installing a stent graft.
Invention is credited to Weiss, Mitchell.
Application Number | 20040002714 10/064070 |
Document ID | / |
Family ID | 29731557 |
Filed Date | 2004-01-01 |
United States Patent
Application |
20040002714 |
Kind Code |
A1 |
Weiss, Mitchell |
January 1, 2004 |
METHOD FOR INSTALLING A STENT GRAFT
Abstract
A first catheter has a return bend formed near its distal free
end and a first magnet is mounted on the distal free end. The first
catheter is introduced through a sheath in a first common femoral
artery into an elongate leg of a stent graft and pulled back until
the return bend positions the first magnet near a truncate leg of
the stent graft. A second catheter having a second magnet on its
distal free end is introduced through a second common femoral
artery and positioned near the first magnet so that the magnets
become interconnected. The second catheter is pulled into the stent
graft, a guide wire is inserted through it, and a second sheath is
introduced into the stent graft. A contralateral limb is deployed
through the second sheath and the second sheath is removed. In
another embodiment, catheters with magnets pull a nephroureteral
stent from a kidney.
Inventors: |
Weiss, Mitchell; (Safety
Harbor, FL) |
Correspondence
Address: |
SMITH & HOPEN PA
15950 BAY VISTA DRIVE
SUITE 220
CLEARWATER
FL
33760
|
Family ID: |
29731557 |
Appl. No.: |
10/064070 |
Filed: |
June 6, 2002 |
Current U.S.
Class: |
606/108 ;
623/1.11; 623/23.7 |
Current CPC
Class: |
Y10S 623/902 20130101;
A61F 2/07 20130101; A61F 2210/009 20130101; Y10S 623/909 20130101;
A61F 2002/067 20130101; A61F 2/954 20130101; A61F 2/90 20130101;
Y10S 623/903 20130101 |
Class at
Publication: |
606/108 ;
623/1.11; 623/23.7 |
International
Class: |
A61F 002/06; A61F
002/04 |
Claims
Now that the invention has been described:
1. A method for installing a contralateral limb to a stent graft
positioned in an abdominal artery to treat an aneurysm, said stent
graft having an elongate leg and a truncate leg, comprising the
steps of: inserting a first guide wire through an incision
endoluminally into a first common femoral artery and pushing said
first guide wire into said abdominal artery until a leading end of
said first guide wire extends beyond a leading end of said stent
graft; introducing a first sheath into said elongate leg of said
stent graft, using said first guide wire to guide said first sheath
into said elongate leg, said elongate leg having a trailing end
received within said first common iliac artery; removing said first
guide wire from said sheath; providing a first catheter having a
return bend formed near a distal end thereof and having a first
magnet means mounted to said distal end; introducing said first
catheter into a lumen of said first sheath and pushing said first
catheter until said return bend emerges from said lumen of said
first sheath; displacing said first catheter in a
distal-to-proximal direction until said first magnet means emerges
from said hollow interior of said stent graft and into the interior
of said aneurysm; providing a second catheter having a second
magnet means on a distal free end thereof, said second magnet means
having a polarity opposite to a polarity of said first magnet
means; introducing said second catheter into a second, opposite
common femoral artery and positioning its distal free end near said
first magnet means so that said first and second magnet means are
attracted to one another and enter into magnetically coupled
relation to one another; pulling said second catheter into the
hollow interior of said stent graft; introducing a second guide
wire into the lumen of said second catheter until the distal free
end of said second guide wire has extended completely through
second catheter and through said stent graft; removing said first
and second catheters; introducing a second sheath over said second
guide wire until the distal free end of said second sheath has
entered the hollow interior of said stent graft; introducing a
contralateral limb through said second sheath until the distal free
end of said contralateral limb has extended from said second sheath
and entered into the hollow interior of said stent graft; said
contralateral limb deploying under its inherent bias so that it
expands in diameter; and withdrawing said second sheath; whereby
blood flows into a first end of said stent graft and out the
bifurcated lower end thereof into left and right iliac
arteries.
2. The method of claim 1, wherein the step of removing said first
and second catheters is accomplished by pulling on said second
catheter until the magnetic coupling between said first and second
magnet means is overcome.
3. The method of claim 1, further comprising the step of employing
a deployment system to facilitate introduction of said
contralateral limb through said second sheath.
4. The method of claim 1, wherein said first magnet means is a
metal band formed of a ferrous material.
5. The method of claim 1, wherein said second magnet means is a
metal band formed of a ferrous material.
6. The method of claim 1, further comprising the steps of: forming
an opening in said first catheter near said distal end thereof;
extending a pull string through said first catheter from a proximal
end thereof, said pull string exiting said first catheter through
said opening; securing a distal end of said pull string to said
distal end of said first catheter in close proximity to said first
magnet means; pulling a proximal end of said first catheter to form
a return bend in the distal end of said first catheter; whereby
said return bend positions the first magnet means in a position
where it may be engaged by said second magnet means.
8. The method of claim 1, further comprising the steps of: forming
an opening in said first catheter near said distal end thereof, in
close proximity to said first magnet means; extending a pull string
through said first catheter from a proximal end thereof, said pull
string exiting said first catheter through said opening; pulling a
proximal end of said first catheter to form a return bend in the
distal end of said first catheter; whereby said return bend
positions the first magnet means in a position where it may be
engaged by said second magnet means.
9. A method for installing a contralateral limb to a stent graft
positioned in an abdominal artery to treat an aneurysm, said stent
graft having an elongate leg and a truncate leg, comprising the
steps of: inserting a first guide wire through an incision
endoluminally into a first common femoral artery and pushing said
first guide wire into said abdominal artery until a leading end of
said first guide wire extends beyond a leading end of said stent
graft; introducing a first sheath into said elongate leg of said
stent graft, using said first guide wire to guide said first sheath
into said elongate leg, said elongate leg having a trailing end
received within said first common iliac artery; removing said first
guide wire from said sheath; providing a first catheter having a
return bend formed near a distal end thereof and having a first
magnet means mounted to said distal end; introducing said first
catheter into a lumen of said first sheath and pushing said first
catheter until said return bend emerges from said lumen of said
first sheath; displacing said first catheter in a
distal-to-proximal direction until said first magnet means emerges
from said hollow interior of said stent graft and into the interior
of said aneurysm; providing a second sheath having a second magnet
means on a distal free end thereof, said second magnet means having
a polarity opposite to a polarity of said first magnet means;
introducing said second sheath into a second, opposite common
femoral artery and positioning its distal free end near said first
magnet means so that said first and second magnet means are
attracted to one another and enter into magnetically coupled
relation to one another; pulling said second sheath into the hollow
interior of said stent graft; removing said first catheter;
introducing a contralateral limb through said second sheath until
the distal free end of said contralateral limb has extended from
said second sheath and entered into the hollow interior of said
stent graft; said contralateral limb deploying under its inherent
bias so that it expands in diameter; and withdrawing said second
sheath; whereby blood flows into a first end of said stent graft
and out the bifurcated lower end thereof into left and right iliac
arteries.
10. The method of claim 8, wherein the step of removing said first
catheter is accomplished by pulling on said first catheter until
the magnetic coupling between said first and second magnet means is
overcome.
11. The method of claim 8, wherein said first magnet means is a
metal band formed of a ferrous material.
12. The method of claim 8, wherein said second magnet means is a
metal band formed of a ferrous material.
13. A method for removing a nephroureteral stent from a kidney,
comprising the steps of: mounting a first magnet means to a first
end of a nephroureteral stent that extends from a bladder to a
kidney through a ureter; mounting a second magnet means on the
distal free end of a catheter, said second magnet means having a
polarity opposite to a polarity of said first magnet means;
introducing said distal free end of said catheter into said bladder
through an urethra; bringing said second magnet means into close
proximity with said first magnet means so that said first and
second magnet means enter into a magnetic coupling with one
another; withdrawing said catheter through said urethra, thereby
pulling said first magnet means and hence said nephroureteral stent
with it.
14. The method of claim 12, wherein said first magnet means is a
metal band formed of a ferrous material.
15. The method of claim 12, wherein said second magnet means is a
metal band formed of a ferrous material.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates, generally, to the medical arts. More
particularly, it relates to a method for endoluminal installation
of a stent graft.
[0003] 2. Description of the Prior Art
[0004] Stent grafts are used to hold arteries open so that blood
may flow therethrough. They also have utility in treating
aneurysms, in effect replacing an artery where the walls of the
artery have ballooned outwardly and are in danger of rupturing.
Stent grafts are formed of materials that are inert to the human
body so that they may be left in place indefinitely. The materials
from which stent grafts are made are highly flexible so that they
may be compressed into a small space such as a lumen of a catheter.
The materials are also highly resilient, i.e., have excellent
memory, so that when a stent graft is pushed out of the lumen of a
catheter, it expands under its inherent bias to its operable
size.
[0005] Tubular stent grafts are relatively easy to deploy in
straight sections of arteries. However, there are areas of the body
where deployment is problematic because a tubular stent graft
cannot be used. A section of the abdominal artery, just slightly
upstream of where it divides into the left and right iliac
arteries, also known as the left and right common iliac arteries,
is prone to the development of aneurysms and is a location where a
tubular stent graft has no utility.
[0006] The stent graft that has been developed for this problematic
area of the abdominal artery is often described as looking like a
pair of pants having a waist part with one long leg and one short
leg depending therefrom. When properly deployed, the waist part and
the short leg thereof are positioned within the aneurysm of the
abdominal artery, just downstream of the renal arteries. The long
leg has a trailing end disposed within a first common iliac artery.
If the short leg were also elongate and if its trailing end could
easily be fitted into the second common iliac artery, then the
positioning of a stent graft in an abdominal artery aneurysm would
not be problematic.
[0007] Deploying a stent graft in an abdominal artery aneurysm so
that blood can flow through the stent graft and avoid putting
pressure on the ballooned arterial walls is difficult because the
waist part of the stent graft must be positioned within the
abdominal artery, and the left and right legs of the stent graft
must fit into the left and right common iliac arteries,
respectively.
[0008] There are two basic designs for endoluminal stents having
utility in the repair of abdominal aortic aneurysms. Two elongate
legs are provided in the first design. A first leg is positioned in
the first iliac artery and a second leg is pulled into the second
iliac artery to form an inverted "Y" configuration. The present
invention pertains to the second design where the stent includes a
long leg and a short leg. An extension for the short leg is
manufactured as a separate piece and is known as a contralateral
limb because it is laterally opposed with respect to the first
elongate leg of the stent graft. The physician inserts the
contralateral limb into the short leg, thereby creating a conduit
from the stent to the contralateral iliac artery and excluding
blood flow from the aneuryismaneurysm.
[0009] Thus, in the second design, an extension for the short leg
must be manufactured as a separate piece, and the physician must
insert the extension for the short leg into the second iliac artery
and try to secure it to the short leg.
[0010] The method most commonly employed to join a contralateral
limb to the short leg of a stent graft is to introduce the
contralateral limb through an incision in the patient's leggroin.
More particularly, the contralateral limb is endoluminally
introduced through a common femoral artery. The leading end of the
contralateral limb is inserted into the trailing end of the short
leg of the stent graft and the trailing end of the contralateral
limb is left in the second common iliac artery to complete the
installation.
[0011] There are several drawbacks to this approach, but the
primary drawback is that it requires a physician to correctly aim
the leading end of the contralateral limb at the trailing end of
the stent graft short leg. This is a very difficult task under
fluoroscopy or other imaging technique. What might look like a
perfect connection may be a complete miss. For example, if the
leading end of the contralateral limb goes directly underneath the
trailing end of the short leg of the stent graft, it will appear to
the physician performing the procedure that the alignment is
perfect and that the job has been successfully completed. The
results of such a misalignment are catastrophic.
[0012] What is needed, then, is an improved method for
endoluminally introducing the leading end of a contralateral limb
into the trailing end of the short leg of a stent graft.
[0013] However, in view of the prior art considered as a whole at
the time the present invention was made, it was not obvious to
those of ordinary skill in the pertinent art how such need could be
fulfilled.
SUMMARY OF THE INVENTION
[0014] The long-standing but heretofore unfulfilled need for an
improved method for installing a contralateral limb to a stent
graft in the area of an abdominal artery aneurysm is now met by a
new, useful, and nonobvious invention. The novel method includes
the steps of inserting a first guide wire through an incision
endoluminally into a first common femoral artery and pushing the
first guide wire into the abdominal artery until a leading end of
the first guide wire extends beyond a leading end of the stent
graft. A first sheath is endoluminally introduced into an elongate
leg of the stent graft, using the first guide wire to guide the
first sheath into the elongate leg. The elongate leg has a trailing
end received within the first iliac artery. The first guide wire is
then removed from the sheath. A first catheter having a return bend
formed near its distal end and having a first magnet means mounted
to the distal end is introduced into a lumen of the first sheath.
The first catheter is pushed into the first sheath until the return
bend emerges from the lumen of said first sheath. The first
catheter is then displaced in a distal-to-proximal direction,
relative to the incision site, until the first magnet means emerges
from the hollow interior of the stent graft and into the interior
of the aneurysm. A second catheter having a second magnet means on
a distal free end thereof is introduced into a second, opposite
femoral artery and positioned near the first magnet means so that
the first and second magnet means (having a polarity opposite to
that of the first) are attracted to one another. The second
catheter is then pulled into the hollow interior of the stent
graft. A second guide wire is then introduced into the lumen of the
second catheter until the distal free end of the second guide wire
has extended completely through the second catheter and through the
stent graft. The first and second catheters are then removed. A
second sheath is introduced over the second guide wire until the
distal free end of the second sheath has entered the hollow
interior of the stent graft. A contralateral limb is then
introduced through the second sheath until the distal free end of
the contralateral limb has extended from the second sheath and
entered into the hollow interior of the stent graft. The
contralateral limb deploys under its inherent bias so that it
expands in diameter. The second sheath is then withdrawn and blood
flows into a first end of the stent graft and out the bifurcated
lower end thereof into the left and right iliac arteries.
[0015] The step of removing the first and second catheters is
accomplished by pulling on the second catheter until the magnetic
coupling between the first and second magnet means is overcome.
[0016] In an alternative embodiment, an opening is formed in a
first straight-in-configuration catheter near its distal end. A
pull string extends through the first catheter from its proximal
end and exits the first catheter through said opening. The distal
end of the pull string is secured to a first magnet means mounted
on the distal end of the first catheter, or to the catheter in very
close proximity to the first magnet. Pulling on the pull string
thus forms a return bend in the distal end of the first catheter
and positions the first magnet to a position where it can be more
easily connected to a second magnet at the second end of a second
catheter that is introduced through the contralateral limb.
[0017] In a variation of the alternative embodiment, an opening is
formed in the distal end of the first catheter in close proximity
to the first magnet means secured to the distal end of the first
catheter. A guide wire extends through the first catheter from its
proximal end and exits through said opening. This configuration
minimizes the profile of the catheter by placing the magnet
therewithin instead of on the outside thereof, while preserving the
lumen for the guide wire.
[0018] In another alternative embodiment, a magnetic band having a
polarity opposite to that of the magnet secured to the distal end
of a first catheter is secured to the distal end of a second
sheath. This eliminates the need for a second catheter. After the
magnets have been coupled to one another, the sheath is pulled and
pushed into the hollow interior of the stent graft. A deployment
system is then employed to facilitate introduction of the
contralateral limb through the second sheath. This eliminates the
need for a second guide catheter, thereby shortening procedure
time.
[0019] In another application of the invention, a nephroureteral
stent is removed from a kidney by mounting a first magnet or
ferromagnetic means to a first end of a nephroureteral stent that
extends from a bladder to a kidney through a ureter. A second
magnet means having a polarity opposite to a polarity of the first
magnet means is mounted on the distal free end of a catheter and
the distal free end of the catheter is introduced into the bladder
through the urethra. The second magnet means is brought into close
proximity with the first magnet means so that the first and second
magnet means enter into a magnetic coupling with one another. The
catheter is then withdrawn through the urethra, thereby pulling the
first magnet means and hence the nephroureteral stent with it.
[0020] An alternative embodiment of the invention comprises the
addition steps of threading a pull string through said catheter,
said pull string having a first end and a second end, establishing
a string aperture proximate to said first magnet, securing said
first end to said catheter coincident to said first magnet whereby
retraction of said second end draws said first magnet toward said
string aperture thereby forming said return bend.
[0021] In all embodiments, one of the magnet means may be provided
in the form of a ferrous material that is secured to the distal end
of its catheter. For example, a ferrous metal band may be strapped
onto the end of a catheter.
[0022] The primary object of this invention is to provide a method
whereby a contralateral limb is attached to the short leg of a
stent graft without requiring a physician to visually guide the
contralateral limb into the short leg.
[0023] A closely related object is to provide a method that
harnesses magnetism to facilitate the steps of the method.
[0024] These and other important objects, advantages, and features
of the invention will become clear as this description
proceeds.
[0025] The invention accordingly comprises the features of
construction, combination of elements, and arrangement of parts
that will be exemplified in the description set forth hereinafter
and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF DRAWINGS
[0026] For a fuller understanding of the nature and objects of the
invention, reference should be made to the following detailed
description, taken in connection with the accompanying drawings, in
which:
[0027] FIG. 1 is a diagrammatic view of a stent graft deployed in
an aneurysm;
[0028] FIG. 2 is the first animation in a series of fourteen
animations that depict the steps of the novel method in
sequence;
[0029] FIG. 3 is the second animation in said series;
[0030] FIG. 4 is the third animation in said series;
[0031] FIG. 5 is the fourth animation in said series;
[0032] FIG. 6 is the fifth animation in said series;
[0033] FIG. 7 is the sixth animation in said series;
[0034] FIG. 8 is the seventh animation in said series;
[0035] FIG. 9 is the eighth animation in said series;
[0036] FIG. 10 is the ninth animation in said series;
[0037] FIG. 11 is the tenth animation in said series;
[0038] FIG. 12 is the eleventh animation in said series;
[0039] FIG. 13 is the twelfth animation in said series;
[0040] FIG. 14 is the thirteenth animation in said series;
[0041] FIG. 14 is the fourteenth animation in said series;
[0042] FIG. 15 is a diagrammatic view of a second embodiment;
[0043] FIG. 15A is a diagrammatic view of an alternative
embodiment;
[0044] FIG. 16 is the first animation isn a series of three
animations that depicts the steps of an alternative embodiment of
the invention;
[0045] FIG. 17 is the second animation in said series;
[0046] FIG. 18 is the third animation isn said series;
[0047] FIG. 19 is a diagrammatic view of a variation of the
alternative embodiment; and
[0048] FIG. 20 is a diagrammatic view of another alternative
embodiment.
DETAILED DESCRIPTION
[0049] Referring to FIG. 1, it will there be seen that the
reference numeral 10 denotes an aneurysm site in an abdominal
artery 11. The renal arteries are denoted 12, 14, the left and
right common iliac arteries are denoted 16, 18, respectively, and
an aneurysm therebetween is denoted 20. A stent graft is denoted 22
as a whole and is of conventional construction. It has a body or
waist area 13 as depicted, an elongate leg 15, and a truncate leg
17. The leading edge of the stent graft is denoted 13a.
[0050] Aneurysm 20 is formed in abdominal artery 11 which extends
from the aortic opening in the diaphragm, not shown, to a
termination point near the fourth lumbar vertebra, not shown, where
it divides into the right common iliac artery 16 and the left
common iliac artery 18, respectively.
[0051] Note in FIG. 1 that a trailing end of elongate leg 15 is
positioned within right common iliac artery 16. No such elongate
leg can be provided for left common iliac artery 18 as a part of
the original construction of stent graft 22 because there are no
means for positioning a trailing end of a second elongate leg
within said left common iliac artery 18.
[0052] The method for installing stent graft 22 in the position
depicted in FIG. 1 is well-known and forms no part of this
invention, per se. Fluoroscopy or other suitable imaging technique
is employed to enable the physician to position the stent graft in
its FIG. 1 position. A suitable imaging technique is employed
throughout the various steps of the novel method.
[0053] The first step of the novel method is depicted in FIG. 2.
Guide wire 24 is endoluminally inserted through incision 26 into
the left or ipsilateral common femoral artery 16 and fed through
said artery until the distal end 24a of said guide wire is beyond
renal arteries 12, 14. Incision 26 is the same incision through
which stent graft 22 is inserted prior to commencement of the novel
method.
[0054] As depicted in FIG. 3, sheath 28 is then advanced into the
ipsilateral side of stent graft 22, using guide wire 24 as a guide
means. Guide wire 24 is then removed, leaving sheath 28 in place as
depicted in FIG. 4.
[0055] FIG, 5 depicts first catheter 30 having magnet 32 at its
distal free end. A return bend 34 is pre-formed in said first
catheter 30, near said distal free end.
[0056] First catheter 30 is inserted into sheath 28 until magnet 32
and return bend 34 have emerged from the distal free end 28a of
sheath 28 as depicted in FIG. 6. Note that first magnet 32 is
positioned interiorly of stent graft 22 at this step of the
method.
[0057] First catheter 30 is then pulled rearwardly, i.e., in a
distal-to-proximal direction, relative to the incision site, until
first magnet 32 emerges from the interior of stent graft 22 into
the interior of aneurysm 20 as depicted in FIG. 7.
[0058] A second catheter 36 (FIG. 8) is then introduced into the
opposite femoral artery 18. Second magnet 38 secured to the distal
free end of second catheter 36 has a polarity opposite to the
polarity of first magnet 32 so that said magnets 32 and 38 are
attracted to one another. Alternatively, one of the magnets could
be made of a non-magnetized ferrous material.
[0059] As indicated in FIG. 9, second catheter 36 is advanced until
the magnets are in close proximity to one another, at which time
they attract one another and become interconnected.
[0060] As depicted in FIG. 10, second catheter 36 is then pulled
into the hollow interior of stent graft 22. This may be
accomplished by pushing on both catheters 30, 36
simultaneously.
[0061] A second guide wire 40 is then introduced into the lumen of
second catheter 36 until its distal free end 40a has extended
completely through second catheter 36 and through stent graft 22 as
depicted in FIG. 11. Note that this positioning of second guide
wire 40 is made possible because the distal free end 36a of second
catheter 36 is disposed in the hollow interior of stent graph 22,
and said positioning is made possible by the magnetic coupling of
magnets 32 and 38.
[0062] First and second catheters 30 and 36 are then removed as
indicated in FIG. 12. This may be accomplished by pulling on second
catheter 36 until the magnetic coupling between magnets 32 and 38
is overcome, followed by retraction of said first and second
catheters.
[0063] Significantly, guide wire 40 as depicted in FIG. 12 has been
placed with confidence into short leg 17 of stent graft 22.
[0064] Guide wire 40 is then used to guide second sheath 44 until
its distal free end 44a has entered the hollow interior of stent
graft 22 as depicted in FIG. 13.
[0065] Contralateral limb 48 is then introduced through second
sheath 44 until its distal free end 48a has extended from said
second sheath and entered into the hollow interior of stent graft
22 as depicted in FIG. 14. Deployment system 50 is employed to
facilitate introduction of said contralateral limb 48 through said
second sheath 44.
[0066] Contralateral limb 48 is then deployed so that it expands in
diameter as indicated by the reference numeral 52 in FIG. 15.
Second sheath 44 is then withdrawn and the procedure is completed.
Blood now flows into the upper end 13a of stent graft 22 and out
the bifurcated lower end thereof into arteries 16 and 18. Thus,
there is no blood pressure on the ballooned walls of aneurysm 20
and there is no affect on the health of the patient if said walls
fail completely.
[0067] In an alternative embodiment, depicted in FIG. 15A, a
magnetic band 47 is secured to the distal end of second sheath 44.
Magnetic band 47 has a polarity opposite to that of magnet 32
secured to the distal end of catheter 30. This eliminates the need
for second catheter 36. After magnets 32 and 47 have been coupled
to one another, sheath 44 is pulled and pushed into the hollow
interior of stent graft 22 in much the same way as magnets 32 and
38 in FIG. 10. Deployment system 50 (FIG. 14) is then employed to
facilitate introduction of said contralateral limb 48 through said
second sheath 44. This eliminates the need for guide wire 40.
[0068] The methods disclosed herein have been in the context of
stent graft deployment, and have resulted in securing access from a
first femoral artery to a second femoral artery. In additional
embodiments of this invention, the same methods disclosed herein
could be used to secure access between two separate points in the
vascular, biliary, genito-urinary, or gastro-intestinal system.
Such "through and through" access is at times beneficial in
performing procedures such as balloon angioplasty of very tight
strictures. After the catheters are coupled, a wire may be passed
from either point of access. The "through and through" access
provided by the wire provides the operator greater control by
creation of a monorail secured at two ends.
[0069] In the alternative embodiment of FIG. 16, first catheter 30
is straight-in-configuration and has an opening 71 formed therein
near its distal end. Pull string 70 is introduced into the proximal
end of first catheter 30 and said pull string exits the lumen of
said first catheter at said opening 71. The distal end of pull
string 70 is then secured to first magnet 32, or to first catheter
30 at the base of said magnet. A return bend is therefore formed in
first catheter 30 when pull string 70 is pulled from its proximal
end, as indicated in FIG. 17. First catheter 30 is then pulled into
waist area 13 of stent graft 22 as depicted in FIG. 18, thereby
positioning said first magnet 32 into a position where it is easily
engageable by second magnet 38 at the distal end of second catheter
36.
[0070] FIG. 17 depicts pull string 70 received through first
catheter 30 out string aperture 71 and secured coincident to first
magnet 32. Retraction of pull string 70 establishes return bend 34
as shown in FIG. 18 wherein first magnet 32 is positioned in
opposing relation to second magnet 38 (FIG. 19).
[0071] A variation of the alternative embodiment is depicted in
FIG. 19. Guide wire 70 exits opening 71 and is placed proximal to
magnet 32 which is affixed into catheter 30 at the end of the
catheter.
[0072] FIG. 20 depicts another use for magnets 32, 38. In this
embodiment, magnet 32 is mounted to a first end of a nephroureteral
stent 60 that extends from bladder 62 to kidney 64 through ureter
66. Magnet 38 is mounted on the distal free end of catheter 36 as
in the first embodiment and is introduced into bladder 62 through
urethra 68. It has an opposite polarity relative to magnet 32 and
thus coupling of the magnets 32, 38 occurs when magnet 38 is
brought into close proximity with magnet 32. Magnet 32 may also be
provided in the form of a ferrous metal band. When the magnetic
coupling has taken place, catheter 36 is withdrawn through urethra
68, pulling magnet or metal band 32 and hence nephroureteral stent
60 with it.
[0073] Having disclosed two multiple novel uses for the novel
method of coupling catheters to one another by magnetic means,
numerous other applications will become apparent to those skilled
in the medical arts.
[0074] It will thus be seen that the objects set forth above, and
those made apparent from the foregoing description, are efficiently
attained. Since certain changes may be made in the above
construction without departing from the scope of the invention, it
is intended that all matters contained in the foregoing description
or shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
[0075] It is also to be understood that the following claims are
intended to cover all of the generic and specific features of the
invention herein described, and all statements of the scope of the
invention that, as a matter of language, might be said to fall
therebetween.
* * * * *