U.S. patent application number 11/120631 was filed with the patent office on 2005-11-17 for implantable device and method for adjustably restricting a body lumen.
This patent application is currently assigned to Uromedica, Inc.. Invention is credited to Burton, John H., Cook, Timothy C..
Application Number | 20050256364 11/120631 |
Document ID | / |
Family ID | 35310300 |
Filed Date | 2005-11-17 |
United States Patent
Application |
20050256364 |
Kind Code |
A1 |
Burton, John H. ; et
al. |
November 17, 2005 |
Implantable device and method for adjustably restricting a body
lumen
Abstract
An implantable device and method for adjustably restricting a
selected body lumen such as the urethra of a patient to treat
urinary incontinence. The device includes an expandable element or
membrane such as a balloon attached pressure-tightly to a flexible
conduit at its forward end and includes a rear port portion
containing an elastic septum and flow connected to the expandable
element by a first passageway. The conduit contains a second
passageway which allows it to be slid along an elongated guide
probe initially inserted surgically into a patient's body adjacent
the body lumen which is to be adjustably restricted. A suitable
flowable material is injected from a syringe source into the device
rear port sufficient to expand the membrane element and restrict
the body lumen to the desired degree. The syringe and guide probe
are removed and the skin incision is closed over the rear port end
of the implanted device. The rear port septum is located under but
near the patient's skin so that if it becomes necessary to
post-operatively increase or decrease the degree of body lumen
restriction it may be easily accessed with the needle of the
syringe.
Inventors: |
Burton, John H.;
(Minnetonka, MN) ; Cook, Timothy C.; (wayzata,
MN) |
Correspondence
Address: |
SCHWEGMAN, LUNDBERG, WOESSNER & KLUTH, P.A.
P.O. BOX 2938
MINNEAPOLIS
MN
55402-0938
US
|
Assignee: |
Uromedica, Inc.
|
Family ID: |
35310300 |
Appl. No.: |
11/120631 |
Filed: |
May 3, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11120631 |
May 3, 2005 |
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09477977 |
Jan 5, 2000 |
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09477977 |
Jan 5, 2000 |
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08873444 |
Jun 12, 1997 |
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6045498 |
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Current U.S.
Class: |
600/30 |
Current CPC
Class: |
A61B 2017/00539
20130101; A61B 17/12 20130101; A61B 17/12013 20130101; A61B
2017/22051 20130101; A61B 2017/00557 20130101; A61B 2017/22062
20130101; A61B 2017/22067 20130101; Y10S 128/25 20130101 |
Class at
Publication: |
600/030 |
International
Class: |
A61F 002/02 |
Claims
We claim:
1. An implantable device adapted for being surgically implanted
within body tissue adjacent to a body lumen, the device comprising:
a pressurizable expandable element, said expandable element being
attached pressure-tightly onto an elongated conduit element near
its forward end, said conduit element including a rear port portion
and having a first passageway connecting said rear port portion and
said forward expandable element, wherein said expandable element
has an initial contracted shape and is expandable to an enlarged
shape by addition of a flowable material provided into said rear
port portion.
2. The implantable device according to claim 1 wherein said rear
port portion has a cavity which is in fluid communication with said
first elongated passageway, and an elastic septum is contained
pressure tightly in the cavity.
3. The implantable device according to claim 1, wherein said
elongated conduit has a second elongated passageway extending from
an opening in the conduit forward tip end to a location rearward
from said expandable element.
4. The implantable device according to claim 1, wherein said
expandable element is attached onto said elongated conduit element
by an adhesive material.
5. The implantable device according to claim 1, wherein said rear
port portion has an outside diameter larger than that of said
elongated conduit.
6. The implantable device according to claim 1, wherein the
construction material is a bio compatible material selected from
the group of polyurethane or silicone.
7. the implantable device according to claim 2, wherein said
elastic septum is retained in said cavity by a clamp ring located
around said rear port portion.
8. An implantable device assembly adapted for a device being
surgically implanted into body tissue of a patient adjacent to a
body lumen for restricting the body lumen, the assembly comprising:
(a) an elongated guide probe member adapted for being inserted as a
guide means into tissue adjacent to an restrictable body lumen of a
patient; (b) an elongated implantable device adapted for being
surgically implanted into the tissue adjacent to the body lumen,
said implantable device including a forward expandable element and
a rear port portion connected together by flexible conduit, said
conduit having a first inner passageway in fluid communication
between said expandable element and said rear port portion and
having a second passageway arranged for being slidable over said
elongated probe member; (c) a source containing a flowable material
and adapted for being removably connected to the rear port portion
of said implantable device, whereby a flowable material from said
source can be introduced through the rear port portion and through
the first passageway of said implantable device so as to expand the
forward expandable element adjacent a body lumen to at least
partially and adjustably restrict the lumen.
9. The implantable device assembly of claim 8 wherein said guide
probe member is a stiff elongated rod having a pointed forward
end.
10. The implantable device assembly of claim 8 wherein said guide
probe member is a flexible guidewire.
11. The implantable device assembly of claim 8, wherein said
implantable device rear port portion contains an elastic septum and
said source is a syringe having a forward facing needle whereby
said needle may be sealingly inserted through said septum and a
flowable material injected from said syringe through the first
passageway to expand the forward expandable element.
12. The implantable device assembly of claim 11, wherein said
syringe includes an axially movable rear plunger element, whereby
the hollow needle is insertable into the elastic septum located in
the rear port portion of the implantable device and a flowable
material injected by the plunger element through the follow needle
and first passageway to expand the forward expandable element.
13. A method for variably restricting a body lumen in a patient,
comprising the steps of: (a) surgically inserting an elongated
probe member into body tissue of a patient to a location adjacent
to a body lumen to be restricted; (b) providing an elongated
implantable device having an expandable element located at its
forward end and having a port portion provided at is rearward end,
sliding an outer passageway of the implantable device along said
probe member, so that the expandable element is positioned adjacent
to the body lumen; (c) injecting a flowable material from a source
into a said implantable device rear port portion, so as to expand
the expandable element sufficient to at least partially restrict
the body lumen, then removing the source; (d) withdrawing the
elongated probe member from the patient's body tissue and from the
outer passageway of the implantable device; (e) positioning said
implantable device rear port portion inside the body tissue and
near the surface of the skin, and (f) closing the patient's skin
over the device rear port portion.
14. A method for variably restricting a body lumen in a patient,
comprising the successive steps of: (a) surgically inserting an
elongated probe member into body tissue of a patient to a location
adjacent to a body lumen to be restricted; (b) providing an
elongated implantable device having an expandable element located
at its forward end and sliding an outer passageway of the
implantable device along the elongated probe member and positioning
the expandable element adjacent to the patient's body lumen; (c)
withdrawing the elongated probe member from the patient's body
tissue and from the outer passageway of the implantable device; (d)
injecting a flowable material from a source into a rear port
portion of said implantable device, and expanding the expandable
element sufficient to at least partially restrict the body lumen,
then removing the source; (e) positioning the rear port portion of
said elongated implantable device inside the patient's body tissue
near the surface of the skin, and (f) closing an opening made in
the patient's skin over the implantable device rear port
portion.
15. The body lumen restriction method of claim 11, wherein the
material injected into the implantable device expandable element is
selected from the group including a saline liquid solution, a gel,
or a slurry of particles in a fluid carrier.
16. The body lumen restriction method of claim 13, wherein the
flowable material is a radiopaque material to facilitate
fluoroscopic visualization.
17. The body lumen restriction method of claim 13, wherein the
elongated probe member and implantable device are surgically
inserted to a location adjacent the urethra of a female
patient.
18. The body lumen restriction method of claim 15 including placing
an implantable device along two opposite sides of the urethra of a
female patient.
Description
BACKGROUND of INVENTION
[0001] The present invention pertains to an implantable device and
method for adjustably restricting a body lumen such as the urethra
by placing an expandable element having the form of a membrane or
balloon adjacent to the body lumen. The invention also includes a
device assembly and method for expansion of the expandable membrane
element to cause displacement of the body tissue adjacent to the
body lumen so as to adjustably restrict or coapt (close) the lumen.
Expansion of the membrane element is accomplished by delivering a
fluid material into a rear port of the implantable device remote
from the expandable element but near the patient's skin, thus
enabling post-operative adjustment with minimal surgical
invasiveness.
[0002] Several devices for body lumen restriction to treat urinary
incontinence are known and disclosed in the prior art, and have
employed various means such as an outer tube for delivery of a
detachable expandable membrane into body tissue. However, the known
prior art devices do not provide any post-operative adjustability
feature for introduction of new material into the expandable
element to change the degree of restriction of a body lumen. These
prior art devices have also proven to be of risk to the patient
with respect to infection or migration back along the tract by
which they were introduced through the body tissue. Such migration
of the implantable device would render the treatment of
incontinence ineffective and the device may even erode into the
urinary tract causing infection and other severe complications.
[0003] For example, U.S. Pat. No. 4,733,393 to Haber et al
discloses a hypodermically implantable genitourinary prosthesis
which provides a extensible, inflatable tissue expanding membrane
to be located in proximal urethral tissues to add bulk to these
tissues for overcoming urinary incontinence by localized increase
in tissue volume. But the prosthesis does not include any means for
post-operative adjustments. U.S. Pat. No. 4,802,479 to Haber et al
discloses an instrument for dispensing and delivering material in
an inflatable membrane for purposes of a genitourinary prosthesis
within the tissues of a patient for overcoming urinary
incontinence. However, the inflatable membrane isolated within the
tissues is not attached to a conduit and a rear filling means
provided immediately below the patient's skin for post operative
adjustment or titration of restriction of the urethral lumen. U.S.
Pat. No. 4,832,680 to Haber et al discloses an apparatus for
hypodermically implanting a genitourinary prosthesis comprising an
extensible containment membrane for retaining a fluid or
particulate matter which is injected from an external source. But
again the distensible membrane is isolated within the patients body
tissues and is not connected to a conduit and rear port close to
the surface of the skin for post-operative adjustment. Moreover, in
an unadjustable device the patient is at risk for retention; where
urine cannot be passed because the membrane was initially filled
too much causing over restriction of the urethra. Such a condition
could lead to kidney damage which would require major corrective
surgery or at minimum use of self-catheterization to empty the
bladder on a regular basis thus increasing the risk of urinary
tract infection (UTI).
[0004] U.S. Pat. No. 5,304,123 to Atala et al discloses a
detachable membrane catheter incorporated into an endoscopic
instrument for implantation into the suburethral region of a
patient. Also, U.S. Pat. No. 5,411,475 to Atala et al disclose a
directly visualized method for deploying a detachable membrane at a
target site in vivo.
[0005] In all of these prior art devices, the expandable membrane
is delivered to the desired location through an outer tube means.
The absences of this requirement in the present invention allows
the device to be smaller in diameter, thus allowing it to be
delivered through a smaller less traumatic surgical tract.
[0006] Also, the present invention utilizes an expandable element
attached remotely to a conduit to facilitate delivery or removal of
fluid from the expandable element via a rear port which is in close
proximity to the patient's skin.
[0007] In the present invention, the presence of the port located
near the surface of the patient's skin affords the additional
advantage of allowing the device to be easily removed through a
small incision in the skin if, for instance, it was to become
infected or malfunction, whereas all the prior art devices would
require major surgery. Furthermore, the presence of the conduit and
rear port left in the device delivery tract will serve to prevent
backward migration of the expandable element along the tract, a
problem which has been noted with prior art devices.
[0008] Ideally, if a patient's situation at some future time
requires a desirable addition or removal of material to or from the
expandable membrane to adjust the restriction and provide a
resultant greater/lesser pressure and resistance on the urethra, it
is desirable if material could be conveniently adjusted in the
membrane. Therefore, the intent of the present invention is to
allow a more normal voiding process while maintaining continence in
the patient. This post-operative adjustment feature promotes normal
voiding patterns for the patient, and appropriate vesicourethral
pressure during voiding.
[0009] Post-operative adjustment could be done in a semi vertical
or horizontal position with the bladder full after anesthesia is
resolved and edema is minimal. Adjustment of the expandable element
could be done by palpating the rear port which contains a septum
for either filling or removing fluid to further titrate the volume
of the expandable membrane. This will allow more natural voiding
while maintaining continence for the patient.
[0010] Because the prior art has not disclosed the components of
the present invention, if a physician were to undertake subsequent
membrane size adjustments with the prior art devices the following
steps would need to be accomplished to make the expandable membrane
adjustable post-operatively:
[0011] (a) in vivo visualization of the membrane and delivery of a
needle deep into the tissue site where the membrane implant
resides;
[0012] (b) access the inside of the membrane by puncturing it to
add or remove material from the membrane, so as to increase or
decrease patient urethral restriction; and
[0013] (c) sealing the membrane so that subsequent loss of fluid
does not occur.
[0014] Thus, an important medical need exists for an improved
implantable device having an expandable membrane element that
incorporates a permanently attached conduit and rear port which can
be accurately delivered adjacent to a desired body lumen site in a
patient, and to which suitable fluid material can be conveniently
and reliably added or removed as required.
[0015] The primary purpose of the invention is to provide an
adjustable implantable device which will restrict urine from
involuntarily escaping from the bladder, thus establishing
continence for the patient. This adjustable component can be done
in a post-operative manner once the patient has resume daily
activity via an evaluation to determine what activities cause
bladder stress and observable incontinence.
SUMMARY OF INVENTION
[0016] The present invention provides an implantable device for
adjustably restricting a body lumen, and is suitable for treating
both males and female persons and primarily those having stress
incontinence. Involuntary loss of urine, for example, may occur
when a person may sneeze, cough or laugh, in which the
intraabdominal cavity pressure increases thus forcing urine out of
the bladder and causes the person to become incontinent. This
incontinent condition may exist especially with women who have had
multiple child births due to the fact that the anatomy has often
times been shifted and the urethra no longer has a normal
anatomical position nor does the surrounding tissue have the muscle
tone necessary to reliably support the bladder in its normal
position.
[0017] It is an object of the present invention to overcome this
incontinence problem by positioning an implantable device adjacent
to at least one side of a patient's urethra so as to adjust liquid
flow resistance in the urethra. This is accomplished by having the
inner surfaces of the urethra contact each other and thereby
provide sufficient flow resistance, so that when pressure is
exerted on the bladder the urethra does not open and discharge
urine. Moreover, whenever the bladder moves anatomically down
because of lack of muscle tone of the pelvic floor, the urethra
remains coapted, (i.e. stays closed) and urine does not flow out of
the bladder and urethra and the patient is continent.
[0018] An important improvement provided by the present invention
resides in the ability to access the implanted port element located
close to the surface of the patient's skin and adjustably restrict
the urethra. This is accomplished by controlling the volume of
flowable material in the expandable element after it has been
implanted in the patient. The post implantation urethral
restriction is realized by the membrane element acting on tissue
adjacent to the walls of the urethral lumen and forcefully closing
the urethral lumen. Voiding of urine from the bladder only occurs
when the intravesicular pressure over comes the resistance
established by the expandable element.
[0019] Accordingly, this invention provides an implantable device
which includes a forward expandable element which can have
generally ellipsoidal or spherical shape attached pressure-tightly
to an intermediate elongated flexible conduit element, which is
flow connected to a rear port portion filling element. An important
feature of the implantable device of the present invention relates
to an expandable element or membrane which is accessible for
subsequent adjustment in volume through the rear port portion
located remote from the expandable membrane element and near but
under a patient's skin. Another important feature of the present
invention over the prior art device is the convenient adjustability
of the forward expandable element for pressure and size while in
vivo.
[0020] Although this invention is useful for both male and female
persons, it is generally described as it relates to females and its
effect immediately adjacent the urethra wall tissues. Use of the
implantable device in females may take place by its being inserted
through a small surgical incision made at one or two opposite sides
of and in the same body plane as the meatis opening of the female
urethra. Delivery of the device is effected by an elongated guide
probe member inserted along either side of the urethra. After the
delivery guide member is in position in the patient's body, the
implantable device with its forward expandable membrane element in
a deflated condition is delivered along the guide probe to near the
bladder neck. The intermediate conduit element must be sufficiently
flexible to permit delivery of the device along the guide probe
member inserted into a outer passageway in the device.
[0021] Twists or coils in the implanted device connecting conduit
tubing may permit the body tissue to grow around it and further
anchor the device in the patient's body. The device connecting
tubing has sufficient longitudinal stiffness in order to allow
insertion over the guide probe and to minimize collapse and
migration, and is made of a bio-compatible material such as
silicone rubber. The septum element is usually a single element for
each expandable element implanted, however, a single septum element
could be used for providing fluid to more than one expandable
element. The septum element is usually disc shaped and made of
silicone rubber.
[0022] The device according to the invention is intended to work
immediately adjacent to the urethral wall of a patient to create an
increase in urethral coaptation and flow resistance. However, in
the prior art devices any tissue change which may occur
post-operatively such as a reduction in tissue edema associated
with the procedure may cause a reduction in clinical effect because
of the reduced coaptation and resistance after the swelling has
subsided. Although some minor degree of adjustability is available
at the time of implantation in the prior art devices, not until
availability of the present invention is it possible to access the
implanted device and adjust the membrane volume after implantation
in a post-operative manner.
[0023] The present invention also provides an implantable device
delivery assembly which is a significant improvement over the prior
art, especially with regard to the mechanism and method of in vivo
adjustability of the implanted membrane element as a convenience to
both the patient and the physician. The equipment assembly for
delivery and activation includes three essential members, which
are--a location guide probe member for delivery of the implantable
device and its placement in the body of a patient, and a source of
suitable flowable material such as a syringe for injection of the
desired flowable material into the implantable device rear port
element.
[0024] In order for the implanted device to act on the urethra of a
patient, it must be properly located in the patient's body tissue
to permit the membrane element to act correctly upon the urethra
and effect its coaptation. After the desired insertion site for the
implantable device is located and it is delivered to that site, the
implanted membrane element which is flow connected to the remote
rear port through the connecting conduit is accessed via the rear
port to deliver a flowable material causing expansion of the
membrane. Because the rear port portion is placed just under the
patient's skin, thereafter adjustment of the membrane pressure and
size is relatively simple, by accessing the rear port septum for
the addition or removal of flowable material into or from the
membrane.
[0025] While this invention has utility by effecting urethral
coaptation for both male and female patients, the mode of delivery
of the device to the site makes it somewhat easier to use for
females due to anatomical differences. The invention as described
herein relates to its use for female patients. According to its
method for use, a physician will initially make a small incision at
either side of the meatis, i.e. opening of the female urethra. This
incision(s) permits a delivery guide probe member to be inserted
into the body tissue alongside of the urethra so as to define the
path of later entry for the implantable device. Next, delivery of
the device along the guide probe is made on either one or two
opposite sides of the urethra, one placement at a time. Lastly, the
implanted device with the expandable membrane element directed to
each location is left in place, with access for adjustment of the
membrane size being available through a remote elastic septum in
the rear port away from the expandable membrane and located
immediately under the skin of the patient.
[0026] In actual use, two of the devices are usually implanted on
opposite sides of the urethra so as to effect a balanced urethral
coaptation and resistance. If after implantation inflation of the
expandable membrane is excessive, thereby creating a
disproportionate urethral resistance by obstructing the patient and
causing a bladder pressure higher than normal during voiding,
damage to the bladder and kidney may ensue. Thus, a post-operative
membrane size adjustment is available to reduce the patient's
bladder pressure during voiding and maintain intravesicular
pressure within normal limits.
[0027] In actual use, it is preferred to implant two individual
devices with individual septums located on opposite sides of the
urethra. Alternatively, the device may be so configured to have one
septum serve both expandable membrane elements. The volume for the
respective expandable membranes can be adjusted up or down by
introducing or removing fluid through a syringe needle inserted
into the septum. Suitable flowable materials for introduction into
the expandable membrane include a saline liquid, a flowable gel, or
a slurry of small particles such as silicone in a fluid carrier.
Moreover, the flowable material may be made radiopague to
facilitate fluoroscopic visualization for post-operative
inspection. After implantation and a period of time has transpired
allowing induced edema during the procedure to subside, the patient
should be evaluated. At that time of evaluation, if the patient is
not voiding in a normal manner, post-operative adjustments can be
made via the rear port access. During the membrane adjustment
procedure, the syringe needle is directed into the device septum to
adjust the membrane with a flowable material. The needle is
provided with a sharp non-coring end to allow the introduction of
material into the membrane. A needle stop within the septum may
also be provided to facilitate correct positioning of the needle
and also reduce risk of piercing the needle completely through the
septum. All of the components are either bonded or molded to one
another prior to its implantation.
[0028] With the present invention, the membrane configuration is
optimized for its intended purpose and the design of the septum is
also optimized for post-operative adjustment of the membrane size.
In the prior art, if post-operative adjustment was attempted the
physician would have had to identify and locate the membrane deep
within the tissue, puncture the membrane with an elongated needle
and either remove or add fluid to decrease or increase urethral
resistance effects respectively. But for the present invention, it
is not necessary to puncture the membrane for size adjustment and
therefore membrane integrity is maintained. Furthermore, for the
present invention it is not necessary to visualize the expandable
element to make in vivo adjustments because of the remote port
located in close proximity to the patients skin in which adjustment
can be made easily. All of the aforementioned features of the
present invention contribute towards maintaining integrity of the
expandable membrane and affording easy access to and adjustment of
the expandable element in a post-operative manner.
BRIEF DESCRIPTION OF DRAWINGS
[0029] This invention will now be described further with reference
to the following drawings:
[0030] FIG. 1 is a perspective view of the implantable device and
its assembly with a syringe source for providing a flowable
material to a forward expandable element according to the present
invention;
[0031] FIG. 2 is a longitudinal cross-sectional view of the
implantable device shown in FIG. 1;
[0032] FIG. 3 is a cross-sectional view taken along line 3-3 of
FIG. 2;
[0033] FIG. 4 illustrates a guide probe member inserted into body
tissue to an implant location adjacent a body lumen of a patient
prior to insertion of the implantable device;
[0034] FIG. 5 shows the implantable device placed over the guide
probe member and partially advanced to the desired location with
the expandable element being deflated;
[0035] FIG. 6 shows the implanted device assembly after being
expanded at the desired location in the body tissue of the patient
so as to displace body tissue toward the body lumen for causing
adjustable restriction of the body lumen.
[0036] FIG. 7 is a cross-sectional view taken along line 7-7 of
FIG. 6; and
[0037] FIG. 8 shows the implantable device rear port portion after
being inserted near but below the skin of a patient.
DESCRIPTION OF INVENTION
[0038] According to the present invention as shown by FIG. 1, there
is provided an elongated implantable device 10, which includes a
forward expandable membrane element 12 shown in its full expanded
size, and is attached pressure-tightly to a central conduit element
14 having a rearward port portion 16 which communicates with the
expandable element 12 through an inner passageway 15 (see FIG. 2).
The conduit 14 has a pointed forward end 14a which extends slightly
beyond the expandable element 12. A syringe 20 including a hollow
needle 21 and a rear axially-movable plunger 22 is provided for
adjustably injecting a suitable flowable material into the device
10 through the rear port portion 16 to expand the membrane element
12.
[0039] As further shown in FIGS. 2 and 3, the central connecting
conduit 14 contains two elongated lumens or passageways. The first
lumen 15 provides an internal passage by which the flowable
material is directed from a cavity 16a in the rear port 16 to
expand the expandable element 12 such as a membrane or balloon. The
conduit 14 is attached integrally to the port element 16 at its
rearward end. The second lumen 17 extends from a front opening 17a
to a rearward opening 17b and serves to receive an elongated guide
probe (see FIG. 4) and effect delivery of the implantable device 10
to a desired location in the body tissue of a patient.
[0040] An important feature of the implantable device 10 having the
first lumen 15 includes a first opening port 15a located in cavity
16a of the port portion 16 between an elastic septum 18 and the
conduit 14 and is connected to the device first lumen 15, so that a
flowable material can be infused therethrough, and a second port
15b serves to direct the working fluid to the expandable membrane
element 12. During adjustment of the volume of the membrane fluid
provided from a hollow needle 21 of syringe 20, is infused through
the septum 18 and continues on through the conduit tubing 14
connected to the expandable membrane element 12. The port portion
16 preferably has a diameter greater than conduit 14 so as to
accommodate the cavity 16a and elastic septum 18, which is retained
securely by a clamp ring 19.
[0041] The entire implantable device 10 including the expandable
membrane element 12 is formed of a biocompatible material such as
silicone or polyurethane elastomer, and the device conduit 14 and
port 16 may be formed as a unitary construction. Optionally, the
membrane element 12, the rear port 16, and connecting conduit tube
14 can be molded as one piece. As shown in FIG. 2, the expandable
membrane 12 is adhered at 13 to conduit tube 14 at its forward end
by a suitable adhesive material.
[0042] The implantable device and assembly according to this
invention includes three main members. The first member provided is
an elongated guide in the form of a stiff solid elongated guide
probe 24 (see FIG. 4) adapted for delivery of the implantable
device 10 to the desired site in the body tissue of a patient as
generally shown by FIGS. 4 and 5. Alternatively, the elongated
guide member can be in the form of a flexible guidewire which has
been initially delivered into the body tissue through a separate
hollow stiff probe that has been inserted to the desired location
in the body tissue. The second member of the assembly is the
implantable device 10 which includes the expandable membrane
element 12 and conduit 14 containing the two lumens or passageways
15 and 17 and having the rear port portion 16. In use, the
implantable device 10 is guided to a pre-determined location
adjacent a body lumen in a patient's body after the elongated solid
guide probe 24 is first surgically inserted into the body tissue of
the patient to establish an initial pathway. The lumen forward end
opening 17a of device 10 is then disposed over the rear end of
probe 24 to guide the device 10 and deliver the expandable membrane
12 (in its contracted shape 12a) to the pre-determined location in
the body tissue adjacent to the lumen which is to be adjustably
restricted. The diameter of passageway 17 is made slightly larger
than that of the probe member 24 to permit the device 10 to slide
easily over the probe member.
[0043] During actual use, a physician will first make a small
incision in the skin 30 of the patient near the restrictable body
lumen 32, and then by visualization means such as fluoroscopy the
solid guide probe 24 is directed to the desired location, depending
upon the anatomy of the patient. Thereafter, the device second
lumen forward opening 17a of the conduit 14 with the expandable
membrane 12 in its initial deflated or contracted condition or
shape 12a, is slid over the rear end 24a of the delivery guide 24.
The delivery guide slides through the second lumen 17 of conduit 14
and exits at rearward opening 17b. As illustrated in FIG. 2,
opening 17b occurs between expandable element 12 and rear port
portion 16. However it might be advantageous to locate opening 17b
close to expandable element 12 or, alternatively, to have the lumen
17 extend through the rear port portion 16.
[0044] If desired, a detent or mark 33 may be provided on the solid
probe 24 which when aligned with a feature on the device 10 such as
rear port 16 will assure that the device 10 is appropriately placed
at the correct depth in the patient's body tissue 30. It may be
necessary to provide the device central conduit 14 in multiple
lengths to facilitate placement of the septum 18 near the patient's
skin. Alternatively, the conduit 14 effective length could be made
adjustable by it having a helical shape similar to that of a coiled
spring.
[0045] After implantable device 10 has been advanced over guide
probe 24 so that the contracted member 12a is in the desired
position adjacent to the body lumen 32, the body lumen 32 may be
restricted to a desired degree by piercing septum 18 with the
needle 21 of syringe 20 and injecting a flowable material through
passageway 15 into the expandable element 12. The physician may
determine the desired degree of restriction of body lumen 32 by
means such as infusing fluid through the body lumen past the
restriction and measuring the back pressure.
[0046] As illustrated by FIGS. 1 and 6, the source of flowable
material is usually a syringe 20 with a hollow needle used to
pierce the elastic septum 18, however alternate fluid containers
with means for making a reversible connection to device 10 could be
used. The flowable material may be, for example, a saline solution,
a flowable gel, or a slurry of particles in a liquid carrier. It
may be advantageous to make the flowable material radiopaque so
that the degree of membrane inflation may be viewed by x-ray.
[0047] An alternative method of delivery of the device 10 could be
to first withdraw solid probe 24 from the body tissue and then
inflate expandable member 12. A further alternative would be to
first place device 10 over the solid guide probe 24 outside the
body and then insert them both into the body tissue as a unit. To
facilitate this latter procedure, it may be desirable that there be
some friction between solid guide probe 24 and the second lumen 17
in conduit 14.
[0048] After the implantable device has been properly positioned
with the expandable member 12 located near the body lumen 32 and
the septum in rear port 16 located near the skin 30, the device is
injected with a flowable material from the syringe 20. Once filling
of the expandable member is complete, the solid probe 24 is
withdrawn from the device leaving the expanded membrane element in
the body tissue. Then the skin incision 31 is closed over the port
16 by means such as a suture 34 as shown in FIG. 8.
[0049] As described, an essential feature of this invention relates
to adjustability of the membrane expansion post-operatively. This
adjustability is effected because the septum 18 is located remote
from the expandable membrane element 12 but near and under the
patient's skin. The port and septum is located by, for instance,
manual palpation of the skin region and the needle of the syringe
is inserted through the skin and septum so as to add or remove
material from the expandable member, thus increasing or decreasing
the restriction of the body lumen.
[0050] To assure proper sealing of the septum element 18, it is
placed in compression within cavity 16a by providing a tight metal
ring 19 which surrounds the port 16 and is smaller in diameter than
the port. When the needle 21 of syringe 20 is withdrawn from the
septum 18 after expansion or adjustment of the expandable element
12, there is positive sealing around the perimeter of septum
18.
[0051] FIGS. 4-8 generally illustrate the method or procedure for
properly implanting the device 10 in the body tissue of a patient.
As shown by FIG. 4, a physician after locating the body lumen such
as a female urethra of a patient, first make a small incision 31
and inserts the guide probe 24 in the body tissue to a desired
location adjacent the body lumen 32. This procedure is usually
carried out under a local anesthetic with visual guidance, for
instance under fluoroscopy by the physician. Next, the physician
takes implantable device 10 and places it over the probe member 24,
through the second lumen 17 per FIGS. 1 and 2, the probe 24
entering at forward opening 17a and exiting at the rear opening
17b. The device 10, for which connecting conduit 14 is sufficiently
flexible, is advanced along the probe 24 into the body tissue
31.
[0052] After the desired location within the body tissue 30a has
been reached, a suitable flowable material is introduced into the
device 10 from a source such as the syringe 20 having hollow needle
21 inserted through septum 18 so as to at least partially expand
the membrane 12, as shown by FIG. 6. Next the probe 24 is removed
and the membrane 12 is expanded further to the desired enlarged
size for restriction of the body lumen 30. The syringe 20 is
removed from the device 10, after which the desired size of
expanded membrane 12 is maintained by the elastic septum 18. Next,
the patient's incision at 31 is surgically closed over the port 16
and septum 18 by sutures at 34.
[0053] Although this invention has been described broadly and in
terms of preferred embodiments, it will be understood that
modifications and variations can be made within the scopes as
defined by the following claims.
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