U.S. patent application number 11/301120 was filed with the patent office on 2006-07-13 for intragastric device for treating obesity.
Invention is credited to Kiyoshi Hashiba, Vihar C. Surti.
Application Number | 20060155311 11/301120 |
Document ID | / |
Family ID | 26966969 |
Filed Date | 2006-07-13 |
United States Patent
Application |
20060155311 |
Kind Code |
A1 |
Hashiba; Kiyoshi ; et
al. |
July 13, 2006 |
Intragastric device for treating obesity
Abstract
An apparatus and method comprising at least one intragastric
member or artificial bezoar made of a digestive-resistant or
substantially indigestible material that is introduced into a
gastric lumen of a mammal for the treatment of obesity. The
intragastric member or artificial bezoar is typically at inserted
into the gastric lumen in a partially compacted configuration,
whereby it is then manipulated into, or allowed to assume, a second
expanded configuration sufficiently large to remain within the
reservoir of the stomach during normal activities and not be passed
through the pylorus into the intestines. In animals, the present
invention has been found to be effective in achieving weight loss
over a several month period, while being easy to place and
retrieve.
Inventors: |
Hashiba; Kiyoshi; (Sao
Paulo, BR) ; Surti; Vihar C.; (Winston-Salem,
NC) |
Correspondence
Address: |
BRINKS HOFER GILSON & LIONE
P.O. BOX 10395
CHICAGO
IL
60610
US
|
Family ID: |
26966969 |
Appl. No.: |
11/301120 |
Filed: |
December 12, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10151720 |
May 17, 2002 |
|
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|
11301120 |
Dec 12, 2005 |
|
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60291790 |
May 17, 2001 |
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60360353 |
Feb 27, 2002 |
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Current U.S.
Class: |
606/153 |
Current CPC
Class: |
A61F 5/0036 20130101;
A61F 5/0003 20130101 |
Class at
Publication: |
606/153 |
International
Class: |
A61B 17/08 20060101
A61B017/08 |
Claims
1. An intragastric device for the treatment of obesity, the
intragastric device comprising a digestive-resistant material that
is expandable from a first configuration to a second configuration,
the first configuration being sufficiently small to permit
introduction of said intragastric device into a gastric lumen of a
mammal, the second configuration being sufficiently large to
prevent said intragastric device from passing through the mammal's
pylorus, wherein said intragastric device is configured to function
as an artificial bezoar, and further wherein said
digestive-resistant material has been one of folded, gathered,
bundled, tied, collected, manipulated and organized to form a
volume displacing mass in the second configuration.
2. The intragastric device according to claim 1 wherein said
digestive-resistive material comprises one or more elements
selected from the group consisting of plastic, nylon, polyesters,
polyurethanes, polyethylenes, polyamides, silicone and
biocompatible polymers to which food will generally not adhere.
3. The intragastric device according to claim 1 wherein said
digestive-resistive material comprises one or more elements
selected from the group consisting of high-density polyethylene,
low-density polyethylene, fluorinated ethylene propylene and
ethylene vinyl acetate copolymer.
4. The intragastric device according to claim 1 wherein the
digestive-resistant material has a resilience which is biased
towards the second configuration.
5. The intragastric device according to claim 1 wherein said
digestive-resistant material comprises a continuous strip of
material that has been folded to form a plurality of loops, said
plurality of loops being connected together in the second
configuration to form the volume displacing mass, the mass having a
shape suggestive of a butterfly or bow-tie.
6. The intragastric device according to claim 5 wherein the
continuous strip of material is folded to form a plurality of
bundles in the first configuration, each of said bundles comprising
a plurality of loops connected together to form a shape suggestive
of a butterfly or bow-tie, and wherein said plurality of bundles
are connected together in the second configuration to form the
volume displacing mass.
7. The intragastric device according to claim 6 wherein each of the
bundles is introduced into the gastric lumen of the mammal
separately.
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. The intragastric device according to claim 1 wherein said
digestive-resistant material comprises a plurality of strips of
material that have been connected together in the second
configuration to form the volume displacing mass, the mass having a
shape suggestive of a butterfly or bow-tie.
13. The intragastric device according to claim 12 wherein the
plurality of strips of material have been connected together to
form a plurality of bundles in the first configuration, each of
said bundles comprising a plurality of strips of material connected
together to form a shape suggestive of a butterfly or bow-tie, and
wherein said plurality of bundles are connected together in the
second configuration to form the volume displacing mass.
14. The intragastric device according to claim 13 wherein each of
the bundles is introduced into the gastric lumen of the mammal
separately.
15. (canceled)
16. (canceled)
17. (canceled)
18. (canceled)
19. The intragastric device according to claim 1 wherein said
digestive-resistant material comprises a sheet of material that has
been folded or pleated in the second configuration to form the
volume displacing mass, the mass having a shape suggestive of a
butterfly or bow-tie.
20. (canceled)
21. The intragastric device according to claim 1 wherein said
digestive-resistant material comprises a continuous thread of nylon
that has tied in the second configuration to form a ball-like
volume displacing mass.
22. The intragastric device according to claim 21 wherein the
continuous thread of nylon is tied to form a plurality of ball-like
masses in the first configuration, and wherein said plurality of
ball-like masses are connected together in the second configuration
to form the volume displacing mass.
23. The intragastric device according to claim 22 wherein each of
said bundles is introduced into the gastric lumen separately.
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
30. (canceled)
31. (canceled)
32. The intragastric device according to claim 1 wherein the
digestive-resistant material is distributed throughout the mass in
the second configuration.
33. The intragastric device according to claim 32 wherein void
spaces are distributed throughout the mass in the second
configuration, the void spaces allowing the passage of gastric
fluid into or through the intragastric device.
34. The intragastric device according to claim 32 wherein the mass
comprises a substantially homogeneous cross-section.
35. The intragastric device according to claim 1 wherein the
digestive-resistant material comprises a surface having a first
contact point and a second contact point, the first contact point
being spaced apart from the second contact point in the first
configuration, the first contact point being in contact with the
second contact point in the second configuration.
36. The intragastric device according to claim 1 wherein the
digestive-resistant material comprises a substantially planar
material.
37. The intragastric device according to claim 1 wherein the
digestive-resistant material comprises an elongate material having
a length that is substantially longer than its width or
thickness.
38. The intragastric device according to claim 1 wherein the volume
displacing mass comprises a flexible or dynamic shape that conforms
to the gastric lumen of the mammal.
39. The intragastric device according to claim 1 wherein the volume
displacing mass is free-floating within the gastric lumen of the
mammal.
40. The intragastric device according to claim 1 wherein the
digestive-resistant material is substantially non-elastic.
41. The intragastric device according to claim 1 wherein the
digestive-resistant material is substantially non-expandable.
42. The intragastric device according to claim 1 wherein the
digestive-resistant material is substantially non-inflatable.
43. The intragastric device according to claim 1 wherein a coupling
mechanism is provided to one of fold, gather, bundle, tie and
organize the digestive-resistant material to form the volume
displacing mass in the second configuration.
44. The intragastric device according to claim 43 wherein the
coupling mechanism comprises a suture, the suture binding the
digestive-resistant material together to form the volume displacing
mass in the second configuration.
45. The intragastric device according to claim 1 wherein the
digestive-resistant material is reconfigurable from the second
configuration to a third configuration while in the gastric lumen
of the mammal, the third configuration having a size and shape
permitting removal of digestive-resistant material from the gastric
lumen of the mammal.
46. The intragastric device according to claim 45 wherein a
coupling mechanism is provided to one of fold, gather, bundle, tie
and organize the digestive-resistant material to form the volume
displacing mass in the second configuration, and further wherein
the coupling mechanism is adapted to facilitate reconfiguration of
the digestive-resistant material from the second configuration to
the third configuration.
47. The intragastric device according to claim 46 wherein the
coupling mechanism comprises a suture, the suture binding the
digestive-resistant material together to form the volume displacing
mass in the second configuration, the suture being severable to
facilitate reconfiguration of the digestive-resistant material from
the second configuration to the third configuration.
48. An intragastric device for the treatment of obesity, the
intragastric device comprising a digestive-resistant non-fluid
material that is manipulated from a first configuration to a second
configuration, the first configuration being sufficiently small to
permit introduction of said intragastric device into a gastric
lumen of a mammal, the second configuration being sufficiently
large to prevent said intragastric device from passing through the
mammal's pylorus, wherein said digestive-resistant material is
manipulated to form a three-dimensional volume in the second
configuration, further wherein the digestive-resistant material is
substantially distributed throughout the three-dimensional volume
in the second configuration.
49. An intragastric device for the treatment of obesity, the
intragastric device being manipulated from a first configuration to
a second configuration, the first configuration permitting
introduction of said intragastric device into a gastric lumen of a
mammal, the second configuration preventing said intragastric
device from passing through the mammal's pylorus, wherein said
intragastric device is configured to function as an artificial
bezoar when in the second configuration, further wherein the
intragastric device comprises a digestive-resistant material that
is manipulated from the first configuration to the second
configuration, the digestive-resistant material being distributed
to form a volume-displacing substantially homogeneous mass in the
second configuration.
50. An intragastric device for the treatment of obesity, the
intragastric device being manipulated from a first configuration to
a second configuration, the first configuration comprising a first
shape that is sufficient to permit introduction of said
intragastric device into a gastric lumen of a mammal, the second
configuration comprising a second shape that is sufficient to
prevent said intragastric device from passing through the mammal's
pylorus, wherein said intragastric device is configured to function
as an artificial bezoar when in the second configuration, further
wherein the intragastric device comprises a digestive-resistant
non-fluid material that is gathered upon itself in the second
configuration to form a volume-displacing mass, the mass comprising
a distribution of said digestive-resistant non-fluid material.
51. An intragastric device for the treatment of obesity, the
intragastric device comprising one or more intragastric members
comprising a digestive-resistant material and being deployable in a
first configuration sized for introduction into the stomach of a
mammal, wherein said one or more intragastric members are
organizable upon deployment within said stomach to form a mass of
said digestive-resistant material having a second configuration
defining a volume effective to substantially reduce the available
reservoir within said stomach, said mass of digestive-resistant
material being further configured to prevent passage through the
pylorus of said mammal.
52. The intragastric device according to claim 51 wherein said mass
of digestive-resistant material includes adaptations for
facilitating a third configuration of said mass while within said
stomach, said third configuration having a size and shape
permitting removal of digestive-resistant material from said
stomach.
53. The intragastric device according to claim 52 wherein said
adaptations comprises a suture that binds said mass of
digestive-resistant material in the second configuration, further
wherein said suture is severed to facilitate the third
configuration of said mass.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of c-pending U.S. patent
application Ser. No. 10/151,720, filed May 17, 2002, which claims
the benefit of U.S. Provisional Application No. 60/291,790, filed
May 17, 2001, and U.S. Provisional Application No. 60/360,353,
filed Feb. 27, 2002, each of which are entitled "Intragastric
Device For Treating Obesity".
TECHNICAL FIELD
[0002] This invention relates to medical devices, and more
particularly to obesity treatment devices that can be placed in the
stomach of a patient to reduce the size of the stomach
reservoir.
BACKGROUND OF THE INVENTION
[0003] It is well known that obesity is a very difficult condition
to treat. Methods of treatment are varied, and include drugs,
behavior therapy, and physical exercise, or often a combinational
approach involving two or more of these methods. Unfortunately,
results are seldom long term, with many patients eventually
returning to their original weight over time. For that reason,
obesity, particularly morbid obesity, is often considered an
incurable condition. More invasive approaches have been available
which have yielded good results in many patients. These include
surgical options such as bypass operations or gastroplasty.
However, these procedures carry high risks, and are therefore not
appropriate for most patients.
[0004] In the early 1980s, physicians began to experiment with the
placement of intragastric balloons to reduce the size of the
stomach reservoir, and consequently its capacity for food. Once
deployed in the stomach, the balloon helps to trigger a sensation
of fullness and a decreased feeling of hunger. These balloons are
typically cylindrical or pear-shaped, generally range in size from
200-500 ml or more, are made of an elastomer such as silicone,
polyurethane, or latex, and are filled with air, water, or saline.
While some studies demonstrated modest weight loss, the effects of
these balloons often diminished after three or four weeks, possibly
due to the gradual distension of the stomach or the fact that the
body adjusted to the presence of the balloon. Other balloons
include a tube exiting the nasal passage that allows the balloon to
be periodically deflated and re-insufflated to better simulate
normal food intake. However, the disadvantages of having a
inflation tube exiting the nose are obvious.
[0005] The experience with balloons as a method of treating obesity
has provided uncertain results, and has been frequently
disappointing. Some trials failed to show significant weight loss
over a placebo, or were ineffective unless the balloon placement
procedure was combined with a low-calorie diet. Complications have
also been observed, such as gastric ulcers, especially with use of
fluid-filled balloons, and small bowel obstructions caused by
deflated balloons. In addition, there have been documented
instances of the balloon blocking off or lodging in the opening to
the duodenum, wherein the balloon may act like a ball valve to
prevent the stomach contents from emptying into the intestines.
[0006] Unrelated to the above-discussed methods for treating
obesity, it has been observed that the ingestion of certain
indigestible matter, such as fibers, hair, fuzzy materials, etc.,
can collect in the stomach over time, and eventually form a mass
called a bezoar. In some patients, particularly children and the
mentally handicapped, bezoars often result from the ingestion of
plastic or synthetic materials. In many cases, bezoars can cause
indigestion, stomach upset, or vomiting, especially if allowed to
grow sufficiently large. It has also been documented that certain
individuals having bezoars are subject to weight loss, presumably
due to the decrease in the size of the stomach reservoir. Although
bezoars may be removed endoscopically, especially in conjunction
with a device known as a bezotome or bezotriptor, they,
particularly larger ones, often require surgery.
[0007] What is needed is a intragastric member that provides the
potential weight loss benefits of a bezoar or intragastric balloon
without the associated complications. Ideally, such a device should
be well-tolerated by the patient, effective over a long period of
time, sizable for individual anatomies, and easy to place and
retrieve.
SUMMARY OF THE INVENTION
[0008] The foregoing problems are solved and a technical advance is
achieved by an illustrative obesity treatment apparatus comprising
at least one intragastric member or artificial bezoar made of a
digestive-resistant or substantially indigestible material that is
introduced into a gastric lumen of a mammal in a first
configuration. The intragastric member or artificial bezoar is
typically inserted into the gastric lumen in a partially compacted
configuration, whereby it is then manipulated into, or allowed to
assume, a second expanded configuration sufficiently large to
remain within the reservoir of the stomach during normal activities
and not be passed through the pylorus and into the intestines. In
animals, the present invention has been found to be effective in
achieving weight loss over a several month period, while being easy
to place and retrieve. Another advance is that the present
invention can be effective at a smaller volume within the stomach
than existing intragastric members, such as balloons.
[0009] In one aspect of the invention, the obesity treatment
apparatus comprises a plurality of elongate plastic strips joined
in the middle by a retaining mechanism, such as a nylon thread, so
that the intragastric device has a shape suggestive of a butterfly
or bow-tie. Alternatively, the intragastric member can comprise a
folded or pleated sheet, elongated fibers or hairs, or other
materials that can assume the expanded configuration while not
causing trauma to the stomach wall of the patient.
[0010] In another aspect of the invention, the obesity treatment
apparatus comprises a plurality of intragastric members, such as
the embodiments described above, which are coupled together in a
set or grouping within the gastric lumen. The intragastric members
are introduced individually into the gastric lumen, and then
attached using a coupling mechanism, which may extend from the
intragastric members themselves, or they can be introduced as a
set, depending on the diameter and design used. A tether tied to
the device, such a nylon thread (e.g., fishing line), can be used
to assist in coupling the plurality of intragastric members
together. Additional components may also be used with the coupling
mechanism to facilitate placement of the set and/or separation of
the individual intragastric members. For example, specially
configured plastic or metal pieces can be attached to the line
bundling the set of intragastric members together to enhance
visibility of the line for cutting with a endoscopic scissor or
scalpel, or to provide a hard surface against which the cutting
instrument can be applied to more easily sever the line.
Irrespective of whether the obesity treatment device includes a
single intragastric member, or a coupling of intragastric members,
the principal requirement is that, once in the stomach, it attains
a shape and size that cannot pass through or lodge in the pyloric
sphincter.
[0011] In another aspect of the invention, the obesity treatment
device includes a delivery system, such as one or more catheters,
to place the intragastric members within the gastric lumen. In one
embodiment, one or more intragastric members are mounted on a
catheter or overtube and secured with cotton threads extending
through the passageway of the delivery catheter via oppositely
placed apertures. A metal wire or loop is then withdrawn, severing
the threads and releasing the intragastric member(s) into the
gastric lumen. The individual intragastric members are then coupled
together by drawing them together via the attached tethering
threads, then secured with a device such as a rubber patch pushed
by an introduced metal tube or similar device.
[0012] Other delivery systems of the present invention involve
constraining the intragastric members, then releasing them in the
gastric lumen. These can include pushing the intragastric member(s)
from an outer delivery catheter, typically by use of pusher member
within the delivery catheter passageway. Other methods include
constraining the intragastric member(s) with a splittable or
dissolvable film or sheath that allows that device to be deployed
in a compact configuration, then allowed to expand when the outer
wrapping or sheath is split by the operator, or is allowed to
dissolve away over time in the stomach. In the latter example, a
delivery catheter may not be necessary.
[0013] While a delivery catheter or other delivery system can be
used to deliver the intragastric members of the present invention,
it has been shown that the intragastric members can generally be
placed endoscopically or blindly by pulling them into the gastric
lumen using a pair of forceps or some other retrieval grasping or
device.
[0014] In yet another aspect of the invention, the intragastric
member can comprise a plurality of expandable members that are
constrained into a first configuration for introduction into the
gastric lumen, whereby the device is manipulated to allow it to
assume a second, expanded configuration for residing in the
stomach. One such example is an intragastric member having a
plurality of strips arranged concentrically and secured at each end
with a tether fixedly attached at the first end and extending
through an internal portion of the device. The second end
attachment is adapted to slide over the tether, and can be drawn or
urged toward the first end attachment to cause the expandable
members to bow outward so as to increase the overall volume of the
device.
[0015] In still yet another aspect of the invention, the
intragastric members can be pre-coupled together with a coupling
mechanism, such as a nylon fishing line, prior to introduction into
the gastric lumen. Because the volume of the grouping in the
stomach increases over time due to mucous accumulation or other
factors, a single device having the overall size of the grouping
(e.g., four devices grouped together) may not be readily removed.
However, by severing the line comprising the grouping mechanism,
the individual intragastric devices of the grouping can be removed
one at a time by using an endoscope and retrieval device.
[0016] In yet another aspect of the invention, the intragastric
member can comprise a single strip of material having a series of
apertures space along the length thereof, wherein the strip of
material is bundled into a series of folds by passing a nylon
thread through the apertures and cinching the strip of material
together. The intragastric member is inserted into the gastric
lumen by passing the apertures of the strip of material over a wire
guide, preferably in separate bundles, until the entire strip has
been accumulated and bundled together inside the gastric lumen with
a nylon thread. The nylon thread can be cut to allow the bundles to
separate, thereby facilitating its removal by grasping and pulling
one end of the strip.
[0017] It has also been contemplated that more than one grouping
may be used at a time. For example, two or more independent
groupings of intragastric devices floating freely in the stomach
may be utilized.
[0018] These and other advantages, as well as the invention itself,
will become apparent in the details of construction and operation
as more fully described below. Moreover, it should be appreciated
that several aspects of the invention can be used with other types
of intragastric devices or procedures used for the treatment of
obesity.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0019] Several embodiments of the present invention will now be
described by way of example with reference to the accompanying
drawings, in which:
[0020] FIG. 1 depicts a pictorial view of an intragastric member of
the present invention;
[0021] FIG. 2 depicts a pictorial view of the embodiment of FIG. 1
with a delivery system;
[0022] FIG. 3 depicts a sectional view of the delivery system of
FIG. 2;
[0023] FIGS. 4-5 depicts a pictorial view of a pair of intragastric
members of the present invention prior to, and after being coupled
together;
[0024] FIGS. 6-7 depict detail views of different embodiments of
indigestible members of intragastric members of the present
invention;
[0025] FIG. 8 depicts a partially sectioned side view of an
expandable intragastric member of the present invention;
[0026] FIG. 9 depicts a pictorial view of an intragastric member of
the present invention being delivered from an outer catheter;
[0027] FIG. 10 depicts a pictorial view of an intragastric member
of the present invention that includes a splittable outer
sheath;
[0028] FIG. 11 depicts a side view of an intragastric member of the
present invention encased in a dissolvable outer package;
[0029] FIG. 12 depicts a pictorial view of an intragastric member
of the present invention being manipulated by a endoscopic
device;
[0030] FIG. 13 depicts a set of intragastric members of the present
invention bundled together by a coupling mechanism;
[0031] FIG. 14 depicts a schematic cross-sectional view taken along
line 13-13 of FIG. 13;
[0032] FIG. 15 depicts a pictorial view of another embodiment of an
intragastric member of the present invention;
[0033] FIG. 16 depicts a pictorial view of the embodiment of FIG.
15 separated into separate bundles and ready for insertion into the
gastric lumen;
[0034] FIG. 17 depicts a portion of the strip material that is used
to form the embodiment of FIG. 15;
[0035] FIG. 18 depicts the insertion of the separate bundles of
FIG. 16 being inserted into the gastric lumen FIG. 19 depicts a
pictorial view of yet another embodiment of an intragastric member
of the present invention;
[0036] FIG. 20 depicts a pictorial view of the embodiment of FIG.
19 separated into separate bundles and ready for insertion into the
gastric lumen;
[0037] FIG. 21 depicts a portion of the strip material that is used
to form the embodiment of FIG. 19;
[0038] FIG. 22 depicts the insertion of the separate bundles of
FIG. 20 being nserted into the gastric lumen;
[0039] FIG. 23 depicts a pictorial view of yet another embodiment
of an intragastric member of the present invention; and
[0040] FIGS. 24 and 25 depict an alternative method of inserting of
an intragastric member of the present invention into the gastric
lumen.
DETAILED DESCRIPTION OF THE INVENTION
[0041] The obesity treatment apparatus 10 of the present invention
depicted in FIGS. 1-25 comprises one or more intragastric members
11, each comprising one or more digestive-resistant or indigestible
member 12 sized and configured such that the intragastric member 11
can be placed into the stomach of a mammalian patient and reside
therein, and being generally unable to pass through the pylorus. As
used herein, the terms digestive-resistant and indigestible are
intended to mean that the material used is not subject to the
degrative effects of stomach acid and enzymes, or the general
environment found within the gastric system over an extended period
of time, therefore allowing the device to remain intact for the
intended life of the device. This does not necessarily mean that
the material cannot be degraded over time; however, one skilled in
medical arts and gastrological devices would readily appreciate the
range of material that would be suitable for use as a long-term
intragastric member.
[0042] Many well-known plastics have suitable properties, including
selected polyesters, polyurethanes, polyethylenes, polyamides,
silicone, or other possible materials. Mammalian hair has been
found to form natural bezoars, and thus, is also a possible
material. However, some materials, such as certain polyamides, have
been found to expand over time, which can be an undesirable
property. Most other natural materials are generally much less
resistant to acids and enzymes, and would therefore typically
require treatment or combination with resistant materials to
function long term, unless a shorter-term placement is intended or
desired.
[0043] In the preferred embodiments, the digestive-resistant or
indigestible member 12 comprises a low density polyethylene having
a thickness of about 40-50 microns. Fluorinated ethylene propylene,
ethylene vinyl acetate copolymer, nylon, or types of polymers that
are biocompatible and to which food will generally not adhere may
also be utilized.
[0044] FIG. 1 depicts a single intragastric member 11 in which the
digestive-resistant members 12 include a plurality of elongate
plastic strips 30 that are secured together in the middle by a
retaining element 34, such as a nylon thread. The thread can be
elongated to serve as a coupling mechanism 26, such as a tether 27.
The number of digestive-resistant members 12 or strips 30 used to
form the intragastric member 11 depends on the material used, their
length and width, and how many intragastric members 11 comprise a
set or grouping. The optimal length of the intragastric member 11
is determined by considering these same factors, as well by what is
determined through experimentation to work best.
[0045] Feasibility studies have been primarily limited to placement
in pigs with both 8 cm and 16 cm intragastric members being used,
both having a total volume of about 40 ml when placed in the
stomach of the animal. Although the experiments were designed to
establish the safety of the device, significant weight loss was
nevertheless observed in the test animals. Although no gastric
ulcers were found in animals with polyester intragastric members,
there was a 20% incidence of gastric ulcers in animals having
polyamide devices.
[0046] Results from human trials may lead to modifications in the
configuration being depicted in the figures of this application.
Nevertheless, it is already understood that the dimensions shape,
and construction of the intragastric member can be quite variable
and still produce the desired results. For example, FIGS. 6-7
depict an alternative digestive-resistant member 12. In the
embodiment shown in FIG. 6, the strips 30 of FIG. 1 are replaced by
digestive-resistant member 12 comprising a folded or pleated sheet
31 of plastic or other material. Either a single sheet 31 or
multiple sheets can be used to form the intragastric member 11 of
this embodiment. The embodiment shown in FIG. 7 depicts an
intragastric member 11 in which the digestive-resistant members 12
comprise a plurality of elongated fibers or hairs 32, typically
made of polymer or other synthetic material.
[0047] In the illustrative embodiments, the retaining element 34
(see FIG. 1) is located about the center of the device to hold the
digestive-resistant members 12 together. However, a skilled artisan
would appreciate that other designs utilizing differently placed
retaining elements 34, or eliminating them entirely, could also be
utilized. For example, FIG. 8 depicts an expandable device 33 that
comprises a retaining element 34 at one end to secure the
digestive-resistant members 12, which in this embodiment are
typically made of a material having a certain degree of stiffness.
The other end is secured by a second, slidable retaining element 41
that is disposed over a tether 27 attached to the first retaining
member 34. The intragastric member 11 is deployed in an elongated
configuration with the retaining elements 34, 41 located near their
maximum possible difference apart. After the device is placed in
the gastric lumen, the slidable retaining element 41 is urged along
the tether 27 and toward the first retaining element 34 by using a
tube, probe, or other device, until the digestive-resistant members
12 have bowed outward, thus increasing the overall dimensions and
volume of the device. The slidable retaining element 41 continues
to grip the tether 27 after the urging mechanism is removed,
retaining the increased dimensions of the intragastric member 11
until further manipulation is needed to reduce its diameter for
removal from the patient.
[0048] Deployment of intragastric member 11 can be accomplished in
a number of ways, depending on the size, number, and configuration
of the devices, or according to physician or patient preference.
FIGS. 2-4 depict one such delivery system 44 in which first and
second intragastric members 24, 25 are mounted over a plastic
overtube 18 and secured by a series of suture ties 43, such as
cotton thread. A wire guide 19 is typically used in the procedure,
and is placed through the passageway 52 of the overtube 18. As
shown in FIG. 3, the overtube 18 includes a plurality of apertures
21, a pair of which (e.g., apertures 22 and 23) are distributed
approximately every 2 cm along the distal portion of the overtube
18. To secure the intragastric members 24, 25, the suture tie is
pulled through the first aperture 22 using a device 42 such as a
loop, hook, snare, etc. It is fed through a releasing mechanism 20,
such as the illustrative wire loop, and then pulled through the
opposite aperture 23. The intragastric members 24, 25 are then
placed on the overtube 18, and the suture ties 43 are secured,
thereby constraining the intragastric members into a first
configuration 14 for delivery. Once the delivery system 44 has been
introduced into the gastric lumen, the releasing mechanism 20 is
pulled back through the overtube 18, thereby severing the suture
ties 43 one by one and releasing the intragastric members 11 into
the gastric lumen where they can assume a second configuration 15
(see FIG. 1) that is sufficiently voluminous such that they cannot
pass from the stomach.
[0049] In order to create an obesity treatment apparatus 10 that
will be retained in the stomach, it may be necessary that the
intragastric members 11 be coupled together to form a grouping or
set 45 of intragastric members. FIG. 4 shows the two deployed
intragastric members 24, 25 that each have a coupling mechanism 26
(tether 27) attached about them such that they can be drawn
together as depicted in FIG. 5. A push member 29, such as a
corrugated metal tube, is placed into gastric lumen by using an
endoscope, and is guided over the tethers 27 to urge a securing
element 28, such as a rubber patch, tightly against the two
intragastric members 24, 25. The tethers 27 can then be cut,
allowing the grouping 45 to float free within the stomach. This
method can also be used to join additional intragastric members 11
to form a larger grouping 45. Likewise, the illustrative delivery
system 44 of FIG. 2 can be used to deliver any practical number of
intragastric members 11, which can then be joined in the manner
described above, or they can be delivered singly or in pairs, and
then grouped together after all of the intragastric members 11 have
been placed.
[0050] FIGS. 9-11 depict intragastric members 11 that are delivered
into the gastric lumen within an outer member 35, such as a sheath,
tube, package, wrapping, etc., and subsequently released. For
example, FIG. 9 depicts a delivery system 44 in which the
intragastric member 11 (or multiple devices) is preloaded into an
outer tube or introducer, then deployed therefrom by being pushed
out by using a pusher member (not shown). The intragastric member
11 is shown twisted to aid in loading and deployment.
[0051] FIG. 10 depicts a delivery system 44 in which the
intragastric member is loaded over a tube 18 (as in FIG. 2), but is
secured by an outer member 35 comprising a splittable sheath 37 or
sleeve made of a thin plastic material. In the illustrative
embodiment, the releasing mechanism 20 comprises a nylon thread or
wire that is looped under and over the sheath 37, such that it can
be withdrawn to tear through the thin material of the sheath 37 to
release the intragastric member(s) 11 mounted on the tube 18. The
releasing mechanism of FIG. 10 feeds into an aperture 21 and
passageway 52 of the tube 18, where it extends to the proximal end
of the apparatus 10. Other types of splittable sheaths 37 can also
be used, such as the COOK.RTM. PEEL-AWAY Introducer Sheath.
[0052] FIG. 11 depicts an intragastric member 11 that includes an
outer member 35 comprising a dissolvable enclosure 38. The
material, such as cellulose, gelatin, or some other dissolvable or
rapidly degrading synthetic or biomaterial material, allows the
intragastric member 11 to be deployed in the first configuration 14
into the stomach, where it expands into the second configuration 15
(see, e.g., FIG. 1) once the outer enclosure 38 has dissolved or
degraded away. The embodiment of FIG. 11 can be delivered with or
without a catheter-based delivery system 44, or swallowed by the
patient, depending on the outer dimensions of the apparatus 10.
[0053] FIG. 12 also depicts a method of delivering the apparatus 10
of the present invention without a catheter or tube 18. It has been
found that the intragastric members 11 can be pulled into the
gastric lumen using an endoscope 39 and endoscopic instrument 40,
such as a forceps, basket, snare, etc. This technique can be
employed to pull groupings 45 (see, e.g., FIG. 4) of intragastric
members 11 into the gastric lumen, as long as the alimentary tract
is sufficiently wide to accommodate the grouping 45.
[0054] FIGS. 13-14 depict a grouping 45 of four intragastric
members 24, 25, 49, 50 that are pre-coupled to one another by a
coupling mechanism 26 prior to introduction into the gastric lumen.
Although such an arrangement or grouping 45 is sufficiently small
such that it can be introduced into the gastric lumen as a set, the
adherence of mucous and other changes that occur within the stomach
environment can, over time, significantly increase the volume of
the apparatus 10 from, for example, an original size of about 60 ml
up to a possible size of about 150 ml. The increased size can make
it very difficult to remove the grouping 45 from the stomach. To
address this problem, multiple intragastric members 45 are grouped
together for introduction, and then cut apart when it is time to
remove them from the patient. The coupling mechanism 26 comprises a
grouping mechanism 46, such as a nylon thread (e.g., standard nylon
fishing line), that is wrapped around the grouping 45 to pull them
into close contact with one another. The grouping is released by
severing the line comprising the grouping mechanism 46 and the
intragastric members 24, 25, 49, 50 are removed one at time using a
retrieval device such as that shown in FIG. 12.
[0055] To assist the operator in cutting the line 46 to release the
grouping 45, two different coupling components 47, 48 are included
in the illustrative embodiment. The first coupling component 47
comprises a curved polymer piece which is traversed by the line 46
in such a manner that the line 46 can be readily visualized under
the scope, thereby providing a place to grasp and/or cut the line
with an instrument extending from the endoscope. The second
coupling component 48 comprises a fishing line swivel, which being
metal, can be readily visualized, as well as providing a hard
surface against which a cutting instrument can be applied to sever
the line 46, especially if the line has proved difficult to cut
using other methods. It also provides an easily accessible point on
the apparatus 10 which can be grabbed with a forceps or other
device.
[0056] FIG. 15 depicts another embodiment of an intragastric member
100 of the present invention. In this embodiment, the intragastric
member 100 comprises a single strip of high-density polyethylene
102 that has been folded and bundled to form eighty-nine (89) loops
104 in the general shape of a butterfly. As best seen in FIG. 17,
the single strip of high-density polyethylene 102 of the embodiment
is formed from a tube of material having a wall thickness of 7.5
microns and a perimeter of 6 cm that has been sliced in half. Each
half of the material is then folded to form a strip 102 having two
walls 106, 108, wherein each wall 106, 108 has a width of 1.5 cm.
Of course, the strip 102 could comprise a different number of walls
106, 108, have a different width and thickness, or be formed from a
tube of material.
[0057] In the embodiment of the intragastric member 100 shown in
FIG. 15, each loop 104 is 40 cm in length. Accordingly, the
intragastric member 100 is formed from single strip 102 having a
total length of approximately 35.6 m.
[0058] The intragastric member 100 is bundled by passing a nylon
thread 110 through an aperture 112 in the strip 102 at the center
of the each loop 104. As best seen in FIG. 17, the apertures 112
are formed in each wall 106, 108 of the strip 102, and are spaced
so that loops 104 are formed 40 cm in length when adjacent
apertures 112 are pulled together to form the intragastric member
100 shown in FIG. 15. In other words, the apertures 112 are located
every 40 cm along the length of the strip 102.
[0059] The embodiment of the intragastric member 100 shown in FIG.
15 may be too large for delivery or insertion into the gastric
lumen while in its bundled, final configuration. Accordingly, the
intragastric member 100 is preferably inserted into the gastric
lumen is stages. For example, and as shown in FIG. 16, the
intragastric member 100 is separated into nine (9) separate bundles
114, each of which comprise approximately ten (10) loops 104 of the
strip 102. The loops 104 of each separate bundle 114 are
temporarily grouped or held together by a twist tie 116 or similar
device. Grouping the separate bundles 114 in this manner improves
the handling of the material and prevents the strip 102 from
becoming tangled or contaminated.
[0060] As shown in FIG. 18, the separate bundles 114 of the
intragastric member 100 are inserted into the gastric lumen one at
a time by using a wire guide 118 such as a Savary-Gilliard.TM. wire
guide, manufactured by Wilson-Cook Medical Inc., Winston-Salem,
N.C. The wire guide 118 comprises a central opening through which
the nylon thread 110 passes. The end of the nylon thread 110 is
connected to or tied around a small piece of nylon tubing 120 that
is sized so as to not pass through the apertures 112 in the strip
102. Prior to the insertion procedure, the nylon tubing 120 is
placed near the distal (forward or insertion) end of the wire guide
118 so as to prevent the strip 102 of the first bundle 114 from
sliding off the end of the wire guide 118.
[0061] Once the distal end of the wire guide 118 is positioned in
the gastric lumen, the first bundle 114 is threaded over the
proximal (rearward) end by passing the apertures 112 over the wire
guide 118. A plastic tube 122 is then positioned over the proximal
end of the wire guide 118, and slid towards the distal end of the
wire guide 118 so as to push the folds 104 of the first bundle
against the nylon tubing 120. This procedure is then repeated by
threading subsequent bundles 114 over the wire guide 118 and
pushing them against the previously inserted bundles 114 until all
of the bundles 114 have been inserted into the gastric lumen. The
bundles 114 are then secured together by pushing a small rubber
stopper or similar device 124 (see FIG. 15) along the wire guide
118 so as to press against the last bundle 114 to be inserted. The
wire guide 118 is then withdrawn so as to leave the nylon thread
110 extending through the apertures 112 of all of the bundles 114.
The nylon thread 110 is then tied or otherwise secured to the
stopper 124 so as to form a complete intragastric member 100 as
shown in FIG. 15.
[0062] To remove the intragastric member 100 from the gastric
lumen, the nylon thread 110 is typically cut so as to release the
folds 104. One end of the strip 102 is then grasped by an
endoscopic or similar device and pulled out of the patient.
[0063] FIG. 19 depicts yet another embodiment of an intragastric
member 200 of the present invention. In this embodiment, the
intragastric member 200 comprises a double strip of low-density
polyethylene 202 that has been folded and bundled to form
approximately forty-five (45) loops 204 in the general shape of a
butterfly. As best seen in FIG. 21, the double strip of low-density
polyethylene 202 of this embodiment comprises a pair of strips 202
each having two walls 206, 208, wherein each wall 206, 208 has a
width of 15 mm and thickness in the range of 40-50 microns.
[0064] In the embodiment of the intragastric member 200 shown in
FIG. 19, each loop 204 is 20 cm in length. Accordingly, the
intragastric member 200 is formed from a double strip 202 of
material having a total length of approximately 18 m (i.e., each
strip 202 has a total length of approximately 18 m). A double strip
202 having longer or shorter lengths may also be used depending on
the desired size and mass of the intragastric member 200.
[0065] The intragastric member 200 is bundled by passing a nylon
thread 210 through an aperture 212 in each strip 202 at the center
of the each loop 204. As best seen in FIG. 21, the apertures 212
are formed in each wall 206, 208 of each strip 202, and are spaced
so that loops 204 are formed 20 cm in length when adjacent
apertures 212 are pulled together to form the intragastric member
200 shown in FIG. 19. In other words, the apertures 212 are located
every 20 cm along the length of the strip 202. In the preferred
embodiment shown, apertures 212 have a diameter of approximately
3.5 mm.
[0066] The embodiment of the intragastric member 200 shown in FIG.
19 may be too large for delivery or insertion into the gastric
lumen while in its bundled, final configuration. Accordingly, the
intragastric member 200 is preferably inserted into the gastric
lumen is stages. For example, and as shown in FIG. 20, the
intragastric member 200 is separated into nine (9) separate bundles
214, each of which comprise approximately five (5) loops 204 of the
strip 202. The loops 204 of each separate bundle 214 are grouped or
held together by a breakable tie 216, made of cotton thread, or
similar device. As will be explained below, grouping the separate
bundles 214 in this manner improves the handling of the material
and prevents the strips 202 from becoming tangled or contaminated
during the insertion thereof.
[0067] As shown in FIG. 22, the separate bundles 214 of the
intragastric member 200 are inserted into the gastric lumen one at
a time by using a wire guide 218 such as a Savary-Gilliard.TM. wire
guide, manufactured by Wilson-Cook Medical Inc., Winston-Salem,
N.C. The wire guide 218 comprises a central opening through which
the nylon thread 210 passes. The end of the nylon thread 210 is
connected to or tied around a small nylon disc 220 that is sized so
as to not pass through the apertures 212 in the strips 202. Prior
to the insertion procedure, the nylon disc 220 is placed near the
distal (forward or insertion) end of the wire guide 218 so as to
prevent the strips 202 of the first bundle 214 from sliding off the
end of the wire guide 218.
[0068] Once the distal end of the wire guide 218 is positioned in
the gastric lumen, the first bundle 214 is threaded over the
proximal (rearward) end by passing the apertures 212 over the wire
guide 218. A pusher tube 222, which may be plastic, metal or some
other suitable material, is then positioned over the proximal end
of the wire guide 218, and slid towards the distal end of the wire
guide 218 so as to push the folds 204 of the first bundle 214,
which remain bundled by tie 216, against the nylon disc 220.
[0069] In the preferred embodiment shown, one or more of the
apertures 212 in each bundle 214 have an increased diameter that is
sufficient to allow one more folds 204 to slide over the outside of
the pusher tube 222. This permits the portion of the strips 202
connected between adjacent bundles 214 to be guided (extended)
along the wire guide 218 without interfering with the deployment of
each bundle 214. In the preferred embodiment shown, those apertures
212 having an increased diameter are approximately 9-10 mm in
diameter.
[0070] This procedure is then repeated by threading subsequent
bundles 214 over the wire guide 218 and pushing them against the
previously inserted bundles 214 until all of the bundles 214 have
been inserted into the gastric lumen. The bundles 214 are then
secured together by pushing a small rubber stopper or similar
device 224 (see FIG. 19) along the wire guide 218 so as to press
against the last bundle 214 to be inserted. The wire guide 218 is
then withdrawn so as to leave the nylon thread 210 extending
through the apertures 212 of all of the bundles 214. The nylon
thread 210 is then tied or otherwise secured to the stopper 224 so
as to form a complete intragastric member 200 as shown in FIG.
19.
[0071] To remove the intragastric member 200 from the gastric
lumen, the nylon thread 210 is typically cut so as to allow the
intragastric member 200 to separate in separate bundles (see FIG.
20). The separate bundles 214, which remain connected to each other
by strips 202, can then be removed one at a time. In the event that
the removal of the intragastric member 200 in separate bundles 214
becomes difficult or problematic, then breakable ties 216 may be
severed to release the folds 204 of one or more of the bundles
216.
[0072] As best seen in FIG. 21, visual markers 226, such as colored
tubing, are sutured to the side of the strips 202 of the first or
last fold 204 on either side of the aperture 212. These markers 226
assist the physician in locating the nylon thread 210, which may be
difficult to identify after the device has resided within the
gastric lumen for an extended period of time. Once the nylon thread
210 is cut, one end of the pair of strips 202, or one of the
bundles 216, is then grasped by an endoscopic or similar device and
pulled out of the patient.
[0073] FIG. 23 depicts yet another embodiment of an intragastric
member 400 of the present invention. In this embodiment, the
intragastric member 400 comprises nylon thread 402 that has been
tied into a series of nylon balls 404. The nylon balls 404 are
inserted into the gastric lumen separately and then connected
together to form a single, larger mass of nylon thread (not
shown).
[0074] The above-described embodiments, particularly the
embodiments of FIGS. 15 and 19, can be deployed using alternative
procedures. For example, and as shown in FIGS. 24 and 25, the
intragastric member 300 could be deployed by extending the strip
302 along a nylon thread 304 that has been formed into a loop 306.
Once the end 308 of the loop 306 has been inserted into the gastric
lumen, then a locking device 310, such as plastic cone (shown in
detail in FIG. 25), is pushed over both strands of the nylon thread
304 so as to close the loop 306. As the loop 306 is closed, the
strip 302 is compressed so as to form an intragastric member 300
having a configuration similar to that shown in FIGS. 15 and 19.
Knots 312 are included along the nylon thread 304 to provide a
ratcheting action with the locking device 310. After the
intragastric member 300 has been deployed inside the gastric lumen,
then the portion of the nylon thread 304 extending beyond the
locking device 310 can be severed with an endoscopic scissors and
removed.
[0075] Alternatively, the strip 302 can be compressed by sliding a
tube (not shown) along one or both halves of the loop 306. In
addition, the intragastric member 300 can be inserted in bundles
(see FIGS. 16 and 20), as opposed to the insertion of a single
strip 302 of material (as described above).
[0076] An anchor stent (not shown) could be utilized to temporarily
secure the end of the nylon thread 304 (or the end 308 of the loop
306) inside the gastric lumen during the insertion procedure. For
example, an anchor stent enclosing a portion of the nylon thread
304 would be inserted into the pylorus and lodged therein. One end
of the nylon thread 304 (or loop 306) enclosed within the anchor
stent is then removed therefrom and pulled out of the subject. The
other end of the nylon thread 304 (or loop 306) remains attached to
the anchor stent. The intragastric device 300 can then be inserted
into the gastric lumen by pushing or sliding the strip 302 (or
bundles) down the nylon thread 304 (or loop 306), the end of which
remains secured within the gastric lumen by the anchor stent. Once
the insertion procedure is removed, then the anchor stent and any
excess nylon thread 304 is removed.
[0077] Experimental testing of the present invention has been
conducted on mammals. In particular, an embodiment of an
intragastric member similar to the embodiment shown in FIGS. 19-21
was inserted into the gastric lumens of a group of ten (10) pigs
for a period of 49 days. No deaths or major complications were
observed in any of the test subjects. The initial weight for the
test subjects was measured to be in the range of 25.0 to 31.2 kg,
with an average weight of 27.8 kg. At the end of the 49 day testing
period, the weight of the test subjects was measured to be in the
range of 29.5 to 39.0 kg, with an average weight of 34.5 kg. The
anticipated weight for the test subjects at the end of the testing
period, in view of the normal and expected growth for these
animals, was 57 kg. Accordingly, the test subjects gained an
average weight that was significantly less than the weight gain
observed in similar animals without the intragastric member.
[0078] Any other undisclosed or incidental details of the
construction or composition of the various elements of the
disclosed embodiment of the present invention are not believed to
be critical to the achievement of the advantages of the present
invention, so long as the elements possess the attributes needed
for them to perform as disclosed. The selection of these and other
details of construction are believed to be well within the ability
of one of even rudimentary skills in this area, in view of the
present disclosure. Illustrative embodiments of the present
invention have been described in considerable detail for the
purpose of disclosing a practical, operative structure whereby the
invention may be practiced advantageously. The designs described
herein are intended to be exemplary only. The novel characteristics
of the invention may be incorporated in other structural forms
without departing from the spirit and scope of the invention.
* * * * *