U.S. patent application number 11/215430 was filed with the patent office on 2006-01-26 for gastric retaining devices and methods.
This patent application is currently assigned to Polymorfix, Inc.. Invention is credited to Daniel R. Burnett, David A. Gallup, Greg Hall.
Application Number | 20060020278 11/215430 |
Document ID | / |
Family ID | 37809481 |
Filed Date | 2006-01-26 |
United States Patent
Application |
20060020278 |
Kind Code |
A1 |
Burnett; Daniel R. ; et
al. |
January 26, 2006 |
Gastric retaining devices and methods
Abstract
Methods, devices and systems facilitate gastric retention of a
variety of therapeutic devices. devices generally include a support
portion for preventing the device from passing through the pyloric
valve or esophagus wherein a retaining member may optionally be
included on the distal end of the positioning member for further
maintaining a position of the device in the stomach. Some
embodiments are deliverable into the stomach through the esophagus,
either by swallowing or through a delivery tube or catheter. Some
embodiments are fully reversible. Some embodiments self-expand
within the stomach, while others are inflated or otherwise
expanded.
Inventors: |
Burnett; Daniel R.; (San
Francisco, CA) ; Hall; Greg; (Redwood City, CA)
; Gallup; David A.; (Alameda, CA) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP
TWO EMBARCADERO CENTER
EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
Polymorfix, Inc.
Hayward
CA
|
Family ID: |
37809481 |
Appl. No.: |
11/215430 |
Filed: |
August 29, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10833950 |
Apr 27, 2004 |
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11215430 |
Aug 29, 2005 |
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10671191 |
Sep 24, 2003 |
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11215430 |
Aug 29, 2005 |
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60525105 |
Nov 26, 2003 |
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60490421 |
Jul 28, 2003 |
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Current U.S.
Class: |
606/153 |
Current CPC
Class: |
A61B 2017/12086
20130101; A61B 17/12022 20130101; A61B 17/12172 20130101; A61B
17/12099 20130101; A61F 5/003 20130101; A61F 5/0036 20130101; A61B
17/12177 20130101; A61B 2017/00867 20130101; A61B 2017/00893
20130101; A61B 2017/00818 20130101; A61B 5/14539 20130101; A61B
5/036 20130101; A61B 2017/1205 20130101; A61B 17/12136 20130101;
A61F 5/0079 20130101; A61B 17/1219 20130101; A61B 5/073 20130101;
A61B 2017/12054 20130101 |
Class at
Publication: |
606/153 |
International
Class: |
A61B 17/08 20060101
A61B017/08 |
Claims
1-113. (canceled)
114. A device for retaining a therapeutic component in the stomach
of a patient, said device comprising: a shape-memory component that
is convertible from an expanded configuration in which said
shape-memory component is sufficiently expanded to prevent passage
of said shape-memory component through said pylorus, to a
reduced-diameter configuration allowing insertion and removal of
said shape-memory component through the esophagus of said patient;
a therapeutic component of small enough size to be contained within
said shape-memory component both in said expanded configuration and
said reduced-diameter configuration; and means for manipulating
said shape-memory component between said expanded and
reduced-diameter configurations externally to said patient.
115. A device for retaining a therapeutic component in the stomach
of a patient, said device comprising: a noninflatable component
that is convertible from an expanded configuration sufficiently
large to be unable to pass through said pylorus, to an unexpanded
configuration allowing insertion and removal of said flow-through
component through the esophagus of said patient; a therapeutic
component of small enough size to be contained within said
flow-through component both in said expanded configuration and said
unexpanded configuration; and means for manipulating said
flow-through component between said expanded and unexpanded
configurations while said flow-through component is inside said
stomach.
116. The device of claim 115, further comprising reversible
attachment means for reversibly attaching said flow-through
component to said therapeutic component and thereby fixing said
device in said expanded configuration.
117. The device of claim 115, further comprising a label detectable
through the body of said patient attached to said therapeutic
device.
118. The device of claim 114, further comprising one or more
therapeutic or diagnostic agents releasably coupled with the device
for release within the stomach.
119. The device of claim 114, further comprising a space occupying
member coupled with the obstructing device for occupying space in
the stomach to treat obesity.
120. The device of claim 114, further comprising at least one
electrode coupled with the device, wherein the electrode engages
the tissue of the stomach, pylorus or duodenum.
121. The device of claim 115, further comprising one or more
therapeutic or diagnostic agents releasably coupled with the device
for release within the stomach.
122. The device of claim 115, further comprising at least one
electrode coupled with the device, wherein the electrode engages
the tissue of the stomach, pylorus or duodenum.
123. A device for reducing effective gastric volume, said device
comprising: a flow-through component that is convertible from an
unexpanded configuration in which said flow-through component is
sufficiently small in cross section to be inserted into the stomach
of a patient through the esophagus of said patient, to an expanded
configuration in which said flow-through components is too large in
cross section to pass through said pylorus once inserted in said
stomach; and means for converting said flow-through component from
said unexpanded configuration to said expanded configuration while
said flow-through component is in said stomach, wherein conversion
from unexpanded to said expanded configuration is accomplished
through shape-memory materials or endoscopic locking in an expanded
configuration, wherein reversal of said expanded configuration to
the unexpanded configuration for removal requires endoscopic
manipulation of the device.
124. The device of claim 123, wherein the expandable support
portion comprises at least one self-expanding material.
125. The device of claim 124, wherein the at least one
self-expanding material is selected from the group consisting of
Nitinol, spring stainless steel and other shape-memory,
super-elastic and spring-loaded materials.
126. The device of claim 124, wherein the self-expanding material
comprises at least one support member for preventing collapse of
the support portion, the support member selected from the group
consisting of rings, coils, cages, struts, scaffolding, baskets,
spokes and umbrellas.
127. The device of claim 126, wherein the support portion comprises
the at least one support member coupled with at least one of
GORE-TEX.RTM., silicone, polyurethane and polyethylene.
128. The device of claim 124, wherein the self-expanding material
comprises a self-expanding foam disposed within at least one of the
expandable support portion and the tissue engagement portion.
129. The device of claim 128, wherein the foam comprises at least
one of polyethylene foam, polyurethane foam and silicone foam.
130. The device of claim 124, wherein the self-expanding material
expands upon contacting one or more substances present in the
stomach.
131. The device of claim 123, wherein a tissue engagement portion
is adapted to temporarily form a seal with the pyloric valve upon
contacting the tissue adjacent the valve, and wherein the tissue
engagement portion is sufficiently compliant to avoid causing
damage to the tissue on contacting it.
132. The device of claim 123, wherein the support portion in the
second configuration has a widest cross-sectional diameter of
between 2.5 cm and 15 cm.
133. The device of claim 123, wherein the combined volume is
between 200 cc and 2000 cc.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of co-pending
U.S. patent application Ser. No. 10/833,950, filed on Apr. 27,
2004, which was a continuation-in-part of U.S. patent application
Ser. No. 10/671,191, filed Sep. 24, 2003, which claims priority to
U.S. Provisional Patent Application Ser. No. 60/490,421, filed Jul.
28, 2003. This application also claims priority to U.S. Provisional
Patent Application Ser. No. 60/525,105, filed Nov. 26, 2003. The
full disclosures of all applications cited in this paragraph are
hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The present invention relates generally to medical devices
and methods. More specifically, the invention relates to devices
and methods for partially and/or intermittently obstructing a
pyloric valve to decrease gastric emptying, such as for treating
obesity.
[0004] Obesity has become a medical problem of epidemic proportions
in the United States. Recent governmental studies estimate that as
many as 40% of Americans are obese (defined as a Body Mass Index
over 30), and of those, almost 20% are morbidly obese.
Unfortunately, there is no indication that these percentages will
decrease and every indication that they will increase in the coming
years. Studies have linked obesity to countless health risks, a
small sampling of which includes cardiovascular disease, cancer,
diabetes, orthopedic injuries and complaints, obstructive sleep
apnea, chronic fatigue and depression. Despite billions of dollars
spent searching for obesity cures, conducting research into
nutrition and exercise, and educating the public about obesity,
efforts to date have been largely ineffective.
[0005] Many Americans have tried combating obesity with diet,
exercise and even medications, to no avail. Most people who lose
weight through diet and exercise gain it back again in a short
period of time. Available medications can have serious side
effects, as was evidenced by the recent scare with the Fen-Phen
dietary medication. Faced with the difficultly of diet and
exercise, nutritional information that seems to change radically
and rapidly, and diet medications and supplements that typically do
not work and may cause serious side effects, many obese people
become frustrated and either decide to remain obese or choose to
pursue a more drastic treatment option.
[0006] The more drastic options typically involve surgical
procedures, such as stomach stapling, other gastric reduction
surgical techniques, placement of a constrictive band around the
outside of the stomach, and gastic bypass. The most well known
procedure, in part due to well-publicized experierices of
celebrities like Al Roker and Carney Wilson, is the gastric bypass
operation, known technically as a Roux-En-Y gastric bypass. In this
procedure, the stomach is actually bypassed, and a very small
stomach-like pouch remains, making a patient feel full after
ingesting a small amount of food. Although gastric bypass can be
highly effective, it is acknowledged to be a very high-risk
operation, with a 1-2% mortality rate, a number of possible
complications such as digestive problems, and a recovery period of
up to 6 months. The other surgical alternatives are also associated
with either high risk, low rate of effectiveness, or both.
[0007] Stemming from the high risks of gastric surgical procedures
and the ineffectiveness of diet and exercise for many obese people,
a number of medical devices have been developed to address weight
loss and obesity, but these too have numerous drawbacks. Some
devices, for example, try to bypass a portion of the stomach or
small intestine by essentially creating a tube or chute through
which food passes without any nutrients or calories being absorbed.
Such devices are described, for example, in U.S. Pat. No. 5,820,584
and U.S. Patent Application Publication Nos. 2003/0040804 and
2003/0109931. Unfortunately, these are designed to cause absorption
problems in a patient, which may reduce intake of calories into the
body but which also typically leads to "dumping" of food too
rapidly through the digestive tract, leading to numerous
gastrointestinal symptoms.
[0008] Another approach, as described for example in U.S. Patent
Application Publication No. 2003/0093117, involves performing a
minimally invasive surgical procedure on a stomach, typically to
reduce its volume. The drawbacks with such approaches are that they
are still relatively invasive and they are typically difficult or
impossible to reverse.
[0009] Other techniques involve placing space-occupying balloons
and other devices within the stomach to make the patient feel full
after eating small amounts of food. One such a device, for example,
is described in U.S. Patent Application Publication No.
2003/0109935. Space occupying devices by themselves, however, may
not be as effective as other treatments, and many currently
available devices have an unacceptably serious risk of collapsing,
passing through the stomach, and lodging somewhere in the
intestines, thus causing a serious and potentially fatal intestinal
blockage.
[0010] Yet another technique that has been attempted for treating
obesity involves slowing down the rate at which food passes from
the stomach, through the pyloric valve at the distal end of the
stomach, and into the duodenum--i.e., the first part of the small
intestine. Some researchers have found, for example, that
stimulation of the gastric vagus nerve may result in reduced
gastric motility leading to a loss of over 20% of excess weight in
a nine month period. In another approach, severing the gastric
vagus nerve may also be effective in treating obesity. These
therapies, however, require invasive, sometimes irreversible,
surgical procedures, and may have adverse effects on the ability of
the vagus nerve to perform other important functions.
[0011] Others have tried slowing gastric emptying by placing
implants or injecting bulking agents into tissue at or immediately
adjacent the pyloric valve. Such techniques are described, for
example, in U.S. Pat. No. 6,540,789 and U.S. Patent Application
Publication Nos. 2003/0153806 and 2003/0158601. In general, such
methods have not been found to be effective and, again, are often
irreversible.
[0012] Therefore, because obesity is such an endemic and serious
health problem, and because currently available treatment options
are often ineffective, extremely risky or both, a need exists for
effective, relatively non-invasive treatments for obesity. Ideally,
such treatments would be relatively easy to use and deploy in a
patient and would help treat obesity without a high risk of side
effects or severe complications. Such treatments would also ideally
be reversible. At least some of these objectives will be met by the
present invention.
SUMMARY OF THE INVENTION
[0013] The present invention provides devices, methods and systems
for obstructing or occluding a pyloric valve to provide weight loss
and in some cases treat or ameliorate obesity. Devices are
generally delivered into the stomach where they expand or are
expanded to partially and/or intermittently obstruct or occlude the
pyloric valve. By partially or intermittently obstructing or
occluding the pyloric valve, contents of the stomach (i.e., food)
are retained longer in the stomach, thus causing a patient to feel
full sooner and longer, and thus leading to reduced food intake and
to weight loss.
[0014] A device is generally configured such that, upon placement
in the stomach, it moves naturally to the pyloric valve and
contacts tissue adjacent the valve to obstruct the valve opening. A
portion of the device is configured to assure that the device
cannot pass through the pyloric valve and into the intestine, while
another portion of the device is configured to contact stomach
tissue adjacent the pyloric valve without damaging the tissue.
During digestion and the natural contractions of the stomach, the
device moves in and out of contact with the valve such that gastric
contents are allowed to pass through to the small intestine, but
the rate of passage is slowed. In a number of embodiments, a device
may be introduced into the stomach either through a catheter device
extending through the esophagus or by a patient swallowing the
device. In some embodiments, the device may be retrieved and
removed through the esophagus, often using the same device that was
used for delivery. In other embodiments the obstructing device may
dissolve over time and pass harmlessly through the digestive tract.
In still further embodiments, the device is constructed as a
retaining rather than an obstructing device, retaining a functional
component such as gastric volume displacement component, a drug
delivery component, or a gastric stimulator in the stomach while
still allowing fluid to pass through the stomach and the
pylorus.
[0015] In one aspect of the present invention, a device for
obstructing a pyloric valve of a stomach includes an expandable
support portion adapted to expand in the stomach from a first
configuration to a larger second configuration, and a compliant
tissue engagement portion coupled with the expandable support
portion and adapted to engage stomach tissue adjacent the pyloric
valve to at least intermittently obstruct the pyloric valve. In the
second configuration, the support portion prevents passage of the
device through the pyloric valve. In general, the support portion
and the tissue engagement portion may have any of a number of
different configurations. In one embodiment, the two portions are
part of one, unitary extrusion, with the support portion having a
greater wall thickness than the tissue engagement portion and/or
containing one or more support members, such as support rings,
lattices, frames or the like. In other embodiments, the two
portions may be separate pieces coupled together. The compliant
tissue engagement portion generally is sufficiently compliant so as
to prevent or avoid injury (such as erosion) of stomach tissue with
which the device comes in contact.
[0016] In some embodiments, though not in all, the expandable
support portion is self-expanding, thus including at least one
self-expanding material. For example, the self-expanding material
may include but is not limited to Nitinol, spring stainless steel
or other shape-memory, super-elastic or spring-loaded materials. In
some embodiments, the self-expanding material includes at least one
support member, such as but not limited to one or more rings,
coils, cages, struts, scaffolding, baskets, spokes or umbrellas.
Such support members may be configured such that, once expanded,
they prevent the device from collapsing and passing into the
intestine. In some embodiments, the support portion includes one or
more support members coupled with at least one material, such as of
GORE-TEX.RTM., silicone, polyurethane or polyethylene. The tissue
engagement portion, in turn, may extend from the support portion
and be made of the same or different material, such as those just
listed.
[0017] In alternative embodiments, the self-expanding material may
include a self-expanding foam disposed within the expandable
support portion and possibly the tissue engagement portion as well.
For example, the foam may comprise polyethylene foam, polyurethane
foam, silicone foam or the like. Like the support members just
described, the expandable foam helps prevent passage of the device
through the pyloric valve. Optionally, in some embodiments, the
self-expanding material expands upon contacting one or more
substances naturally present in the stomach.
[0018] In some embodiments, the support portion and the tissue
engagement portion comprise at least one of GORE-TEX.RTM.,
silicone, polyurethane and polyethylene, with the wall thickness of
the support portion being greater than the wall thickness of the
tissue engagement portion. In such a device the support portion may
also include one or more support members, such as Nitinol rings or
the like. In some embodiments, the tissue engagement portion is
adapted to temporarily form a seal with the pyloric valve upon
contacting the tissue adjacent the valve, and the tissue engagement
portion is sufficiently compliant to avoid causing damage to the
tissue on contacting it.
[0019] In various embodiments, the obstruction device may have any
suitable dimensions, configurations or the like. In one embodiment,
for example, the support portion in the second configuration has a
widest cross-sectional diameter of between 2.5 cm and 15 cm. The
support portion and tissue engagement portion, in one embodiment,
have a combined volume in the second configuration greater than 200
cc. This combined volume, in some embodiments, is sufficient to
allow the device to act as a space occupying device (as well as a
pyloric valve obstructing device) for treating obesity. In addition
to its dimensions, the specific gravity or buoyancy of the device
may enhance its ability to contact and obstruct the pyloric valve.
In one embodiment, for example, the device has a specific gravity
of between 0.25 and 4.0. Some embodiments may include one or more
chambers for introducing a gas or fluid to adjust the buoyancy of
the device, or other mechanisms for adjusting buoyancy.
[0020] As mentioned, the support portion and tissue engagement
portion may have any suitable shape in various embodiments. In some
embodiments, for example, the device may have an overall
cross-sectional shape of a circle, ellipse, triangle, diamond,
rectangle, square, star, combinations thereof or the like. In one
embodiment, for example, the device may have an oblong or tubular
shape. In some embodiments, the device is hollow, with one or more
openings to allow passage of stomach contents in and out of the
hollow portion. In another embodiment, the device is cone-shaped,
with the tissue engagement portion disposed toward an apex of the
cone and the support portion disposed toward a base of the cone.
Another embodiment may be shaped like a cup. As will be described
further below, a number of suitable alternatives are possible in
various embodiments.
[0021] Some embodiments of the device also include a positioning
member extending from the tissue engagement portion and having a
shape adapted to pass at least partially through the pyloric valve
to position the device over the pyloric valve. In one embodiment,
the device further includes an inner plug and a compliant outer
shell. The shell is movable from a first configuration in which it
overlaps at least part of the positioning member to a second
configuration in which it overlaps at least part of the plug. In
this embodiment, the plug and a first portion of the shell in the
second configuration act as the support portion, and a second
portion of the shell in the second configuration acts as the tissue
engagement portion. In one embodiment, the shell in the second
configuration is generally cone-shaped. The outer shell may be made
of any suitable material(s), but in one embodiment it comprises a
material such as GORE-TEX.RTM., silicone, polyurethane or
polyethylene, with the wall thickness of the first portion being
greater than the wall thickness of the second portion. The thicker
first portion provides some of the support function, while the
thinner second portion provides the tissue engagement function. In
some embodiments, the outer shell is movable from the first
configuration to the second configuration by applying force to the
shell with a distal end of an elongate catheter device. Also in
some embodiments, the inner plug may be solid and may have a
largest cross-sectional diameter of at least 10 mm.
[0022] Some of the embodiments including a positioning member may
further include a retaining member coupled with a distal end of the
positioning member for maintaining the device in intermittent
contact with the pyloric valve. In some embodiments, the retaining
member self-expands from a first configuration to a second
configuration. Such a self-expanding retaining member may expand
within the stomach or within the duodenum, in various embodiments.
In some embodiments, the retaining member and the obstructing
member are in fluid communication through the positioning member. A
cross-sectional diameter of the retaining member may be either
smaller or larger than a cross-sectional diameter of the support
portion in the second configuration, according to various
embodiments.
[0023] In various embodiments, the retaining member may include any
of a number of different features. For example, in one embodiment
the retaining member includes at least one hole, ring, loop or
other surface feature for attaching a removal device, for removing
the obstructing device from the stomach. In one embodiment, the
retaining member includes at least one radiopaque marker or
material for facilitating visualization of the device. In some
embodiments, the retaining member is adapted to deliver at least
one therapeutic or diagnostic agent to an intestine distal to the
pyloric valve. For example, the retaining member may include a
degradable material carrying the therapeutic or diagnostic agent.
Alternatively, the retaining member may include one or more
housings for releasably containing the therapeutic or diagnostic
agent. In other embodiments, the therapeutic or diagnostic agent
comprises a coating over at least part of the retaining member. In
some embodiments, the retaining member includes an imaging device
for imaging an intestine distal to the pyloric valve. The retaining
member may also include a chemical measuring device for measuring
levels in an intestine of at least one of lipids, sugars, alcohols,
drugs, pH levels, pancreatic secretions, biliary secretions and/or
other dietary or physiological chemicals.
[0024] A retaining member and/or a positioning member having
certain dimensions may be advantageous in various embodiments. For
example, in one embodiment a retaining member has a cross-sectional
diameter of between 0.5 cm and 3.0 cm. In some embodiments, the
positioning member has a length of at least 3.0 cm. In some
embodiments, the positioning member has a cross-sectional diameter
of 2 cm or less. The positioning member may have a general shape
adapted to permit the device to intermittently move into and out of
contact with the pyloric valve, such as a cylindrical shape or the
like. In some embodiments, the positioning member is adapted to
self-expand from a first diameter to a larger second diameter
within the pyloric valve. In some embodiments, a distal end of the
positioning member is weighted.
[0025] In a number of embodiments, the device is deliverable into
the stomach through an esophagus with the support portion in the
first configuration. In some embodiments, for example, a
biodegradable covering is disposed over at least the support
portion, the covering being adapted to constrain the support
portion in the first configuration for delivery into the stomach
and to degrade in the stomach to release the support portion from
constraint. Whether including such a cover or not, in some
embodiments the device is adapted to be swallowed by a patient with
the support portion in the first configuration. Such a swallowed
device may further include a retaining cord removably coupled with
the device and adapted to extend from the device through the
patient's esophagus to the patient's mouth. The cord may retain the
device in the stomach until it expands from a first configuration
to a second configuration, and then may be removed to allow the
obstructing device to contact the pylorus. Optionally, the cord may
provide for removal of the device if it does not properly deploy in
the stomach. In some cases, the cord may be swallowed and may
dissolve in the patient's stomach.
[0026] In other embodiments, the device may removably couplable
with an endoscope, an orogastric tube or any other suitable
elongate delivery device for delivery of the device to the stomach
through the esophagus. In some embodiments, the device is adapted
to be delivered through a lumen of a tube extending from the mouth
through the esophagus into the stomach. Optionally, the support
portion may be collapsible from the second configuration to the
first configuration for removal of the device through the
esophagus. Alternatively, the device may comprise one or more
biodegradable materials so as to degrade over time and pass through
the pyloric valve and the rest of a digestive system. Such
biodegradable materials may include but are not limited to
cellulose, polyethylene glycol, collagen, polylactic acid and/or
other polymers.
[0027] The device as a whole may include any of a number of various
features in various embodiments. For example, in one embodiment the
support portion and/or the tissue engagement portion may include
one or more radiopaque materials, dyes and/or markers. One
embodiment may further include one or more therapeutic or
diagnostic agents releasably coupled with the device for release
within the stomach. Optionally, some embodiments include an imaging
device coupled with the obstructing device for imaging the stomach,
the pyloric valve, and/or the intestine distal to the pyloric
valve. Some embodiments may include a chemical measuring device
coupled with the obstructing device for measuring levels in the
stomach of lipids, sugars, alcohols and/or the like. Some
embodiments may include a space occupying member coupled with the
obstructing device for occupying space in the stomach to treat
obesity. Some embodiments may include one or more electrodes
coupled with the device and removably attachable to stomach tissue.
In such embodiments, a power source for applying energy to the
electrodes, as well as other features, may be housed within the
device. Electrodes may be coupled with the device via one or more
cords or tethers.
[0028] In another aspect of the invention, a device for obstructing
a pyloric valve of a stomach comprises an obstructing member
adapted to expand in the stomach from a first configuration to a
larger second configuration and a positioning member extending from
the obstructing member. As described above, the positioning member
has a shape adapted to pass at least partially through the pyloric
valve to position the obstructing member over the pyloric valve. In
some embodiments, the obstructing member self-expands from the
first configuration to the second configuration.
[0029] In some embodiments, the obstructing member comprises an
inner plug and a compliant outer shell. The shell is movable from a
first configuration in which it overlaps at least part of the
positioning member to a second configuration in which it overlaps
at least part of the plug. The plug and a first portion of the
shell in the second configuration act as the support portion, and a
second portion of the shell in the second configuration acts as the
tissue engagement portion. The inner plug and outer shell may have
any of the features already described. The device as a whole may
also have any of the features described above, in various
embodiments. For example, some embodiments further include a
retaining member as previously described.
[0030] In another aspect of the invention, a system for obstructing
a pyloric valve of a stomach includes a pyloric valve obstructing
device and a delivery device for delivering the pyloric valve
obstructing device to the stomach through the esophagus. The
pyloric valve obstructing device includes an expandable support
portion adapted to expand in the stomach from a first configuration
to a larger second configuration and a compliant tissue engagement
portion coupled with the expandable support portion and adapted to
engage stomach tissue adjacent the pyloric valve such that the
device at least intermittently obstructs the pyloric valve. This
obstruction device may optionally be self-expanding and may include
any of the other features described above in various
embodiments.
[0031] In some embodiments, the delivery device comprises an
elongate flexible catheter. For example the flexible catheter may
comprise an endoscope, an orogastric tube or the like in various
embodiments. In some embodiments, the flexible catheter defines a
lumen in which the obstructing device is housed during delivery.
Such a flexible catheter may optionally further include a coupling
mechanism for releasably holding the obstructing device within the
lumen during delivery. The delivery device may also be adapted to
remove the obstructing device from the stomach through the
esophagus, in some embodiments. In an alternative embodiment, the
device may be delivery in a collapsed state alongside an
endoscope.
[0032] In alternative embodiments, the delivery device comprises a
biodegradable caplet for containing the obstructing device to allow
it to be swallowed by a patient, the biodegradable caplet
dissolving within the stomach. In these or other embodiments, the
obstructing device may comprise one or more biodegradable materials
so as to degrade over time and pass through the pyloric valve and
the rest of a digestive system. Such biodegradable materials may
include but are not limited to cellulose, polyethylene glycol,
collagen, polylactic acid and/or other polymers.
[0033] In some embodiments, the system further includes a space
occupying member coupled with the obstructing device for occupying
space in the stomach to treat obesity.
[0034] In another aspect of the present invention, a method for
obstructing a pyloric valve of a stomach involves delivering a
pyloric valve obstructing device through an esophagus to the
stomach and releasing the obstructing device in the stomach to
allow it to expand from a first configuration to a larger second
configuration. As has been described above, the obstructing device
in the second configuration is adapted to at least intermittently
contact and obstruct the pyloric valve.
[0035] In some embodiments, releasing the obstructing device
involves releasing the device from constraint to allow it to
self-expand from the first configuration to the second
configuration. For example, the obstructing device may be delivered
to the stomach via an elongate flexible catheter, tube or scope
advanced through an esophagus. In other embodiments, releasing the
obstructing device involves allowing a patient to ingest the
obstructing device in its first configuration. In some embodiments,
for example, the device may be folded or compressed for swallowing,
with the device unfolding or expanding upon arrival in the stomach.
In another embodiment, delivering the device involves allowing the
patient to ingest a biodegradable capsule containing the
obstructing device in the first configuration, the biodegradable
capsule degrading in the stomach to allow expansion to the second
configuration.
[0036] Although some methods involve releasing a self-expanding
obstructing device, other embodiments may involve actuating the
expansion, using one or more delivery devices. For example, in some
embodiments the method further involves inflating the obstructing
device within the stomach before releasing it. Further details of
inflatable obstructing devices and methods for their use can be
found in U.S. patent application Ser. No. 10/671,191, of which the
present application is a continuation-in-part and which was
previously incorporated by reference. In alternative embodiments,
the method may further involve moving an expandable shell of the
obstructing device from a first position to a second position to
expand the obstructing device from its first configuration to its
second configuration. For example, in one embodiment the shell may
be invert from a position facilitating delivery of the device to a
position for obstructing the pyloric valve, using a distal end of a
catheter delivery device. In some methods, it may also be possible
to adjust buoyancy of the obstructing device before or after
releasing it to allow it to migrate naturally within the stomach to
contact and obstruct the pyloric valve. Adjusting the buoyancy, for
example, might involve introducing a fluid or a gas into one or
more chambers of the device.
[0037] In many, if not all, embodiments, delivery of an obstructing
device is reversible. Reversibility may be achieved by a number of
different techniques. In one embodiment, for example, the method
for obstructing the pyloric valve further involves collapsing the
obstructing device from the second configuration to the first
configuration and removing the obstructing device from the stomach
through the esophagus. An alternative embodiment involves cutting
the obstructing device into multiple pieces and removing the
obstructing device from the stomach through the esophagus. In
either of these embodiments, the delivering, releasing, collapsing
and removing steps may in some cases be achieved via one or more
elongate flexible catheters, tubes or scopes advanced through an
esophagus. In other embodiments, releasing the obstructing device
in the stomach causes the device to begin to degrade. In such
embodiments, reversibility is achieved by the device degrading over
time and passing harmlessly through the digestive tract.
[0038] In some embodiments, the method further includes maintaining
the obstructing or occluding device in at least intermittent
contact with the pyloric valve by providing the device with a
portion that extends at least partially through the pyloric valve.
In some embodiments, a first portion of the obstructing or
occluding member expands from the first configuration to the second
configuration in the stomach, and a second portion of the
obstructing or occluding member passes through the pyloric valve
into adjacent intestine before expanding from the first
configuration to the second larger configuration. Optionally, a
bridging portion may extend between the first and second portions,
through the pyloric valve, which may expand within the stomach or
the pyloric valve. The bridging portion will have a length that
allows it to pass through the gastric opening with the first and
second obstructing or occluding portions on opposite sides of the
opening and is slightly longer than the passage through the opening
itself to allow the bridging portion to move longitudinally and
intermittently for short distances within the passage and thereby
permit the obstructing or occluding members to intermittently
obstruct or occlude the passage.
[0039] The method may include additional features, such as
visualizing at least one radiopaque marker or material of the
obstructing device. In some embodiments, multiple radiopaque
markers may be used to visualize the orientation of the device. In
some case, the entire device is made of a radiopaque material. In
another embodiment, the method includes acquiring one or more
images of the stomach, the pyloric valve and/or the intestine,
using an imaging device coupled with the obstructing device. In
some embodiments, the obstructing member has a size in its second
configuration that is sufficiently large as to act as a
space-occupying device for further treating obesity. In other
embodiments, the method may further involve expanding a
space-occupying member coupled with the obstructing member within
the stomach to further treat obesity.
[0040] In yet another aspect of the present invention, a method for
obstructing a pyloric valve of a stomach involves passing a pyloric
valve obstructing device in a first configuration through a lumen
of an elongate catheter device extending through an esophagus to
the stomach, advancing the obstructing device at least partially
out of a distal end of the catheter device, and expanding the
obstructing device from the first configuration to a second larger
configuration using the catheter device. In one embodiment, for
example, expanding the obstructing device involves inverting a
compliant shell covering part of the device from a first, collapsed
configuration to a second, expanded configuration, using a distal
portion of the catheter device. Optionally, the method may further
involve releasing the obstructing device from the catheter
device.
[0041] These and other aspects and embodiments of the present
invention are described in further detail below, with reference to
the drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIGS. 1A to 1C show cross-sectional views of one variation
of a pyloric corking device designed to partially and/or
intermittently obstruct a gastric opening in an unexpanded,
partially unexpanded, and fully expanded configuration,
respectively.
[0043] FIGS. 2A to 2D show side views of variations of the device
utilizing occlusion members of different shapes.
[0044] FIGS. 3A to 3C show cross-sectional views of another
variation of the pyloric corking device.
[0045] FIG. 4A shows a side view of yet another variation of the
device having a tapered bridging member.
[0046] FIG. 4B shows a side view of yet another variation of the
device having conical occlusion members held at a distance from one
another.
[0047] FIGS. 5A and 5B show side views of yet another variation of
the device having a single occlusion member and alternative anchor
members.
[0048] FIGS. 6A to 6C show cross-sectional views of the stomach and
one variation for nasogastric (or endoscopic) placement of a
non-ingestible variation of the device.
[0049] FIGS. 7A to 7C show cross-sectional views of the stomach and
another variation for nasogastric (or endoscopic) placement of a
non-ingestible variation of the device.
[0050] FIGS. 8A to 8D show cross-sectional views of the stomach and
yet another variation for placement of a variation of the device
through ingestion.
[0051] FIGS. 9A to 9D show cross-sectional views of the stomach and
yet another variation for placement of another variation of the
device through ingestion.
[0052] FIGS. 10A to 10D show cross-sectional views of the stomach
and one variation for removal of the device.
[0053] FIGS. 11A and 11B show top and perspective views,
respectively, of an alternative variation of the device
incorporating multiple prongs designed to intermittently obstruct
the pyloric valve.
[0054] FIGS. 12A and 12B show side and top views, respectively, of
another variation of the device incorporating multiple prongs
designed to intermittently obstruct the pyloric valve.
[0055] FIGS. 13A to 13D show cross-sectional views of an
alternative use of the device for preventing gastroduodenal reflux
during tube feeding.
[0056] FIGS. 14A to 14D show cross-sectional views of an
alternative use of the device in combination with one or several
gastric fillers.
[0057] FIGS. 15A to 15D show cross-sectional views of a device
designed to partially displace intragastric volume and
intermittently obstruct a gastric opening, according to one
embodiment of the present invention.
[0058] FIG. 16 shows a cross-sectional view of a device as in FIGS.
15A to 15D with a rupture.
[0059] FIG. 17A shows a cross-sectional view of a device having a
positioning member and a retaining member, according to one
embodiment of the invention.
[0060] FIG. 17B shows a cross-sectional view of a device having a
positioning member with an inflation port, according to one
embodiment of the invention.
[0061] FIGS. 18A and 18B show cross-sectional views of two
different embodiments of a device for obstructing a pyloric valve,
according to two embodiments.
[0062] FIGS. 19A and 19B show side views of an device for
obstructing a pyloric valve, according to another embodiment.
[0063] FIGS. 20A to 20C illustrate a method for delivering and
deploying the device of FIGS. 19A and 19B.
[0064] FIGS. 21A and 21B are cross-sectional views of one variation
of the device. In FIG. 21A, the device is shown as it is being
introduced past the esophageal sphincter. In FIG. 21B, the device
is shown fully placed in the stomach.
[0065] FIGS. 22A and 22B are close-up views of the device, with
FIG. 22A showing the device close to but not obstructing the
pylorus and FIG. 22B showing the device obstructing the
pylorus.
[0066] FIG. 23 shows retention of the device after an accidental
rupture in vivo.
[0067] FIG. 24A is a cross sectional view of the device with an
anchoring intestinal bulb, and FIG. 24B is a cross-sectional view
of the device with anchoring intestinal tubing and a distal
inflation port.
[0068] FIG. 25A is a cross sectional view of the device with
supportive internal caging. FIG. 25B is a cross sectional view of
the device with a shape memory external shell.
[0069] FIGS. 26A, 26B, and 26C illustrate a device within the scope
of the invention, that supports and retains a functional component
such as a gastric volume reducer, a drug pump or a gastric
stimulator inside the stomach without obstructing the pylorus, and
can be inserted and removed at will by a physician. In FIG. 26A,
the device is shown fixed in a relaxed configuration that allows
for retention in the stomach. In FIG. 26B, the device is shown in
an intermediate configuration, and in FIG. 26C, the device is shown
in a deformed configuration for removal or insertion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0070] FIGS. 1A to 1C are cross-sectional views showing the
expansion, respectively, of one variation of a pyloric corking
device which is designed to partially and/or intermittently
obstruct a gastric opening, particularly the pyloric valve. In this
particular variation, FIG. 1A illustrates the device 4 in an
unexpanded or uninflated state and ready for delivery and/or
insertion into the pyloric valve. FIG. 11B shows the distal
occlusion member 14 in an expanded state. In use, once the device 4
has been placed, e.g., in the pyloric region or beyond, the distal
occlusion member 14 (or "retaining member") may be inflated through
the influx of any number of biocompatible fluids or gases, e.g.,
saline, water, air, nitrogen, etc., through the tubing 8 leading to
the inflation port 6, which may be self-sealing. Tubing 8 may
include any number of delivery tubes such as catheters, endoscopes,
etc.
[0071] The distal occlusion member 14 may be configured to inflate
before the inflation of proximal occlusion member 16 by fabricating
the inflatable member of distal occlusion member 14 with a material
which is more easily distensible relative to a material of the
proximal occlusion member 16. Materials which may be used in
fabricating the occlusion members 14, 16 may include any number of
materials such as silicone, silicone elastomers, latex,
polyurethane, PTFE, FEP, etc. Alternatively, self-expanding
materials, such as foam or hydrogels which typically expand upon
contact with fluids, may be utilized within the occlusion members
14, 16. If such self-expanding materials are utilized, they may be
disposed in the occlusion member 14, 16 and a fluid such as saline,
may be infused to expand the materials. Different self-expanding
materials may be incorporated in the distal occlusion member 14
than in the proximal occlusion member 16 to obtain differing radial
pressures exerted by the expanding materials.
[0072] In yet another alternative, an expanding scaffolding or
supporting structure of any kind may be utilized within each of the
occlusion members 14, 16. Such a scaffold or structure may be made
of a shape memory foam, a shape memory alloy or super-elastic
alloy, such as Nitinol, or shape memory polymers. The scaffold or
structure may be compressed into a delivery configuration and then
either allowed to expand into the desired occlusive shape by
self-expansion or by supplying an activation energy, e.g.,
electrical, heat, RF energy, etc. In either case, the distal
occlusive member 14 may be positioned distal of the pyloric valve
and then inflated or expanded into its larger configuration. It may
then be pulled proximally against the pyloric annulus, at which
point proximal occlusive member 16 may be inflated or expanded by
infusion through port 6, as shown in FIG. 1C. With both occlusion
members 14, 16 inflated or expanded, bridging member 10 connecting
the two may span the pylorus. Bridging member 10 may be of various
diameters, such as 1 mm and less, which does not significantly
obstruct the pyloric sphincter, up to 8-10 mm in diameter, which
does typically obstruct the pyloric sphincter, or any other
suitable diameter.
[0073] Bridging member 10 may be designed to have a flexible length
sufficient to allow the occlusion members 14, 16 to maintain its
position with respect to the pyloric valve yet still enable the
members 14, 16 to move. Proximal occlusion member 16 may move from
fully obstructing the pyloric valve to moving proximally of the
pyloric valve to the extent that distal occlusion member 14 allows
member 16 to move. This movement may be elicited by the natural
movements of the gastric lumen (stomach) and muscles surrounding
the pyloric valve. Thus, when proximal occlusion member 16 is moved
proximally, the pyloric valve is only partially obstructed and may
allow for the intermittent passage of food between the bridging
member 10 and the valve. Because any food within the stomach is
retained for longer periods of time, feelings of satiation may be
initiated sooner and prolonged so that the patient consumes less
food. Moreover, to allow for the relative movement of the occlusion
members 14, 16, bridging member 10 may be of a length which is
sufficient to allow for its placement through the pyloric valve (or
through another gastric opening) such that there is sufficient
tolerance for the occlusion members 14, 16 to move proximally and
distally relative to the pyloric valve. For instance, in the event
that a patient's pyloric valve extends about 2 cm in length, the
bridging member 10 is preferably longer than 2 cm, for example, up
to 8 cm in length. Moreover, while occlusion members 14, 16 are
inflatable or expandable, bridging member 10 itself may be
configured to inflate or expand in diameter.
[0074] A visible dye or marker, preferably being highly visible,
may optionally be infused into one or both of the occlusion members
14, 16 to function as a safety measure. Alternatively, one or both
of the occlusion members 14, 16 may optionally be fabricated from a
material which is highly visible and visually distinct from tissue
so that in the unlikely event of an occlusion member 14, 16
rupturing, the dye or pieces of the occlusion member 14, 16 may
become visible once passed from the body. This may indicate to the
patient or physician that a rupture of the device has occurred.
[0075] Another variation may incorporate slow-releasing drugs
infused into the materials covering the device or materials
incorporated into the device. These drugs, which may be any number
of drugs, may slowly infuse into the patient by drug release into
the intestinal tract or through contact with the patient.
Alternatively, the devices may incorporate electrical stimulation
technologies. For instance, electrical probes may extend from a
surface of the device for insertion into the surrounding tissue or
electrodes may be formed over a surface of the device instead.
[0076] In yet another alternative, the occlusion members 14, 16 may
be covered by an erodable or biodegradable covering over one or
both members 14, 16. Such a covering may be configured to constrain
one or both members 14, 16 and once the device has been ingested or
placed within the gastric lumen, contact with the surrounding
fluids may naturally erode the covering thus allowing the covered
occlusion member to expand or inflate. In another variation,
proximal and distal occlusion members may each be covered by
different materials each configured to erode at differing rates or
in different environments, as described in further detail
below.
[0077] In the variation shown in FIGS. 1A to 1C, the device 4 may
include an optional lumen 18 defined through the device 4. Optional
lumen 18 may allow for the passage of fluids and food through the
device 4 entering the lumen 18 through entry port 2 and exiting
through the exit port 20. The lumen 18 may be designed to allow for
the passage of a reduced volume of food through the device 4, in
which case the device 4 shown may be configured with a relatively
shortened bridging member 10 to inhibit the relative movement of
the device 4 relative to the pylorus. With this variation, the
lumen 18 has been configured so that it may be capable of actively
pumping or metering the contents of the gastric lumen 74 into the
intestine 76 through the device 4. In such a case, the need for the
device 4 to be able to move to un-occlude the pyloric valve is
removed. As shown in the figures, an optional pump or active
metering valve 12 may be incorporated into the device 4. Pump or
valve 12 may be configured to simply open and allow for the passage
of the stomach contents through lumen 18 and valve 12 upon sensing
the presence of foreign objects, such as food, in the stomach or
upon sensing a predetermined pressure from the contents. Other
sensing parameters may include temperature and pH levels.
Alternatively, the pump or valve 12 may be configured to actively
pump the stomach contents through the lumen 18 via a pumping
mechanism automatically activated by pump or valve 12 or externally
activated by the patient or physician through wireless
communication. In the case where the device is configured with a
valve 12, the valve may be configured as a unidirectional valve to
allow the flow of fluids and food only from the stomach to the
intestinal tract.
[0078] The device 4 could have any shape provided that the shape
and/or total volume of the proximal occlusion member 16 is
sufficient to prevent its passage through the pyloric valve and
into the intestines. FIGS. 2A to 2D show side views of different
shape variations which are possible for use as occlusion members.
For instance, FIG. 2A shows a side view of a device variation 22 in
which proximal and distal occlusion members 24, 26 have a
cross-sectional shape along a longitudinal axis defined by the
device 22 in the form of circles, to form spherical occlusion
members. Although proximal and distal occlusion members 24, 26 are
illustrated having equally sized diameters, the diameters may be
varied depending upon the desired shape and device configuration.
For instance, proximal occlusion member 24 may be configured to
have a diameter larger than distal occlusion member 26.
Alternatively, a device having the opposite configuration may also
be utilized, although this may be less preferable. Lumen 28 and
pump or valve 12 may be optionally included, again depending upon
the desired device configuration.
[0079] FIG. 2B shows another device variation in which proximal and
distal occlusion members 30, 32 may have a cross-sectional shape
along a longitudinal axis defined by the device in the form of
ellipses, to form ellipsoids. The major axes of the
elliptically-shaped occlusion members 30, 32 are preferably
oriented perpendicularly relative to the longitudinal axis of the
device in this variation, although various angles may be formed as
well. FIG. 2C shows the variation in which proximal and distal
occlusion members 34, 36 may be formed as triangles, to form
conically-shaped occlusion members. In this variation, bridging
member 38 may be minimal in length and may simply be formed by the
intersection of the occlusion members 34, 38 to form a waist
region. FIG. 2D shows yet another variation in which proximal and
distal occlusion members 40, 42 may be formed as diamond shapes, to
form a variation of conically-shaped occlusion members. This
variation may also form a waist region 44.
[0080] Although these variations show specific shapes, these are
merely intended to be illustrative of the various types of shapes
which may be utilized and is not intended to be limiting. For
instance, any shape, such as rectangles, squares, etc., which may
function to occlude a gastric opening and prevent the device from
falling therethrough may be utilized and are within the scope of
this disclosure. Moreover, various combinations of the different
shapes as occlusion members on a single device may also be
utilized, such as a device having a distal occlusion member in the
shape of a sphere and a proximal occlusion member in the shape of a
cone.
[0081] FIGS. 3A to 3C show cross-sectional views of another
variation of a pyloric corking device which is also designed to
intermittently obstruct a gastric opening. Similar to the device
shown in FIGS. 1A to 1C, this particular variation omits the use of
a lumen defined through the entire device 46. This device 46 may
also incorporate any of the features described above for expanding
the occlusion members. For instance, foam of varying expansion
pressures may be utilized to ensure that expansion occurs in the
distal occlusion member 50 prior to expansion in the proximal
occlusion member 48 upon the injection of a fluid, e.g., saline or
water, into the device 46. The device 46 is configured so that the
influx of fluids from the infusion tubing 8 through the entry port
6 is channeled through the lumen 52 of the central portion from the
proximal occlusion member 48 to the distal occlusion member 50. The
device 46 may also be placed in the same manner as a device as in
FIGS. 1A to 1C, as described in further detail below. This
variation may also incorporate an inflation port 6, which may be
metallic, so that removal of the device 46, if necessary, can be
accomplished through the simple placement of a magnetically tipped
suction catheter. The catheter, when appropriately placed, may
cause the device to deflate by applying a suction force to
facilitate the easy removal of the device 46 from the pyloric
valve. With a metallic ring placed around the inflation port of the
device, the magnetically tipped suction catheter can be advanced
into the patient, or placed using a nasogastric tube. A sensor can
then indicate that the magnet has engaged the metallic ring, a
vacuum can be activated, and the entire device deflated through
rupture of a pressure-sensitive barrier or through the simple
application of vacuum forces. The device 46 can thus be removed
through any endoscopic or percutaneous approach, e.g., an oro- or
nano-gastric approach. While this variation may have a lumen 52
connecting the proximal 48 and distal 50 occlusion members, this
lumen 52 may be closed to gastric space and instead be used to
communicate an inflation fluid to inflate the occlusion members 48,
50. The occlusion members of the device 46 may have any shape as
described above, for instance in FIGS. 1A to 2D.
[0082] Yet another variation of the device is shown in FIG. 4A. In
this variation, the device 54 may have a bridging member 60 which
is tapered. The bridging member 60 may be tapered to become wider
along its length from the distal occlusion member 58 to the
proximal occlusion member 56. The tapered bridging member 60 may be
utilized to facilitate movement of the device 54 to un-occlude the
pyloric valve. As the pyloric valve contracts about the bridging
member 60, the taper may aid in moving the device proximally. The
angle of the taper may be varied, depending upon the desired
results, as may the size and shapes of the occluding members 56,
58.
[0083] FIG. 4B shows another variation similar to that shown above.
In this variation, the device 55 may have occlusion members 57, 59
having conically-shaped members which are connected via a bridging
member 61. This bridging member 61 may have a length which holds
occlusion members 57, 59 at a distance from one another sufficient
to enable the device 55 to move relative to the pyloric valve. The
device 55 may inflate or expand the occlusion members 57, 59 using
any of the methods disclosed herein and the device 55 may also
optionally incorporate a central lumen and a passive or active
valve or pumping mechanism, if desired.
[0084] In another embodiment, the distal occlusion member may be
omitted entirely. FIG. 5A, for instance, shows a side view of an
alternative variation 62 in which the bridging member 66 (or
"positioning member") may extend at some length, e.g., 5 cm or
greater, from a proximal occlusion member 64. The bridging member
66 may be placed within the intestinal tract, e.g., the duodenum,
while held in place by the proximal occlusion member 64 abutting
the pyloric valve. The positioning of the proximal occlusion member
64 relative to the pyloric valve may be maintained by the
frictional forces generated by the bridging member 66 rubbing
against the walls the intestinal tract. The occlusion member 64 may
function in the same manner as described above in intermittently
un-occluding the pyloric valve during stomach contractions and
movement, but may be held in place by the length of the bridging
member 66. Although the distal end of the bridging member 68 may be
free-floating in the intestinal tract, it may optionally be
weighted by a weight 68 or by a number of hooks or barbs 72 for
attachment to the intestinal walls, as shown in the device 70 of
FIG. 5B.
[0085] It is furthermore within the scope of this disclosure that
certain features between the different device variations described
herein may be incorporated into various combinations. For instance,
a device having a proximal occlusion member having a spherical
shape and a distal occlusion member having a conical shape may be
utilized. As a further example, this device may also incorporate
various methods to inflate or expand the distal occlusion member in
a different manner as the proximal occlusion member. Moreover, this
device may also have a biodegradable covering over only one
occlusion member and may also incorporate the valve and/or pump
integrated within the device and may also optionally include a
lumen defined throughout the length of the device. These examples
are merely intended to be illustrative of the various combinations
which may be employed by combining various aspects from different
variations described herein and are intended to be within the scope
of this invention.
[0086] FIGS. 6A to 6C show cross-sectional views of the stomach and
one variation for nasogastric (or endoscopic) placement of a
non-ingestible, active variation of the device 4. As the device 4
is delivered through the esophagus 78, it may be in a compressed,
un-inflated, or un-expanded configuration, as shown in FIG. 6A,
while being positioned via the optional tubing 8. Once the device 4
has been positioned to span the pylorus with the occlusion members
in the stomach 74 and duodenum 76, respectively, the device 4 may
be inflated or expanded using any of the methods described above,
as shown in FIG. 6B. The tubing 8 may then be detached and the
device 4 left in place, as shown in FIG. 6C.
[0087] FIGS. 7A to 7C show cross-sectional views of the stomach and
another variation for nasogastric (or endoscopic) placement of a
non-ingestible, passive variation of the device 46. As above, the
device 46 may be advanced through the esophagus 78 while in a
compressed, un-inflated, or un-expanded configuration, as shown in
FIG. 7A. As shown in FIG. 7B, once the device 46 has been placed
spanning the pylorus with the occlusion members in the stomach 74
and duodenum 76, respectively, the device may be inflated or
expanded and the tubing 8 may be detached and the device 46 left in
place, as shown in FIG. 7C.
[0088] FIGS. 8A to 8D show cross-sectional views of the stomach and
yet another variation for placement of a passive (or
"self-expanding") embodiment of the device 80. As shown in FIG. 8A,
the device 80 may be simply ingested. As it enters the stomach 74,
gastric fluids may erode an acid sensitive coating over the
inflation port of the proximal occlusion member 82. Once the
coating has degraded, the proximal occlusion member 82 may be
configured to expand or inflate, as shown in FIG. 8B. Once the
expansion or inflation has occurred, the device 80 will remain in
the stomach 74 and eventually the distal occlusion member 84 may
pass into the duodenum 76 while still in its un-expanded or
un-inflated state due to the natural contractions of the stomach,
as shown in FIG. 8C. Once the distal occlusion member 84 has passed
into the duodenum 76, an alkaline sensitive coating over the distal
occlusion member 84 may be eroded and expansion or inflation of the
distal occlusion member 84 will occur with the device spanning the
pyloric valve, as shown in FIG. 8D. The covering over the distal
occlusion member 84 may be configured to erode only once it has
contacted the acidic environment specific to the duodenum 76, where
the pH level is approximately 6. In order to facilitate removal,
the two occlusion members 82, 84 may be connected by a central,
hollow lumen 86, as described above, with a barrier 88 designed to
rupture upon the application of a predetermined pressure level.
Thus, with application of a vacuum having the appropriate pressure
level, the barrier 88 may be configured to rupture and the entire
device 80 may be deflated.
[0089] FIGS. 9A to 9D show cross-sectional views of the stomach and
yet another variation for placement of a passive variation of the
device 90 through ingestion. In this alternative variation, the
device 90 can be ingested orally. As the device 90 enters the
stomach 74, shown in FIG. 9A, both the proximal and distal
occlusion members 82, 92, respectively, may be configured to
inflate upon erosion of acid-sensitive coatings over the inflation
port or device 90, as shown in FIGS. 9B and 9C. Once inflation or
expansion has been accomplished, the distal occlusion member 92
will eventually be passed due to its smaller size (approximately
the diameter of the dilated pyloric valve 5-15 mm) while the
proximal occlusion member 82 will remain in the stomach 74 due to
its larger size, e.g., 15 mm or greater in diameter and up to 60 mm
in diameter due to physiologic limitations in the pyloric region of
the stomach, as shown in FIG. 9D. Thus, one occlusion member 92 may
be designed to be small enough to be passed through the pyloric
valve while the proximal occlusion member 82 may be designed to be
retained in the stomach 74 with both occlusion members 82, 92
inflating in the stomach 74. One of the occlusion members can have
an inflation port covered with an acid-sensitive coating while the
other is acid-resistant bur erodes at the pH found in the intestine
(approximately 6.0). Thus, once the device is ingested, one of the
occlusion members will expand retaining the device in the gastric
space after which gastric motility will eventually move the
remaining uninflated occlusion member into the intestine. Once the
second occlusion member contacts the intestinal tract, the
inflation port may be eroded by the intestinal milieu and the
second portion may slowly inflate leaving the device spanning the
pyloric valve.
[0090] A number of different alternatives and variations may be
employed in self-expanding or "passive" pyloric valve obstructing
devices and methods such as those just described. In some
embodiments, a device may be folded, compressed or otherwise formed
into a smaller configuration for swallowing by a patient, without
using a biodegradable coating. Upon passing through the esophagus
into the stomach, the folded device may unfold due to one or more
shape-memory Nitinol support rings or other self-expanding support
members. In any swallowing embodiment, a device may also include a
tether that extends from the device, back through the esophagus to
the patient's mouth. Such a tether may be used for retaining the
obstructing device in the stomach until it expands, retrieving the
obstructing device if it does not deploy as desired in the
patient's stomach and/or the like. In some embodiments, the tether
may be swallowed to dissolve in the stomach. In other embodiments,
a swallowed device may contact the pyloric valve but not include a
bridging member for spanning the valve. Other variations are
contemplated within the scope of the invention, according to
various embodiments.
[0091] FIGS. 10A to 10D show cross-sectional views of the stomach
74 showing one variation for removal of the device 80 (passive
variation illustrated). The device 80 is shown in FIG. 10A between
the stomach 74 and the duodenum 76. As seen in FIG. 10B, a magnetic
tipped suction catheter or endoscope 94 is introduced and the
device 80 may be deflated and removed, as shown in FIGS. 10C and
10D. In contacting the inflatiori port 6 with the catheter 94, the
tip may be configured with an electrical contact as an aid in
determining whether the catheter 94 has properly contacted the
inflation port 6. Alternatively, the device 80 may be removed
through endoscopy or it may be designed to degrade over time and
eventually be passed through the intestines.
[0092] In other embodiments, an obstruction device may be removed
by deflating or collapsing the device and removing it through a
lumen of a catheter device. In one embodiment, the device may be
cut into small pieces and removed through a catheter lumen. in yet
another embodiment, the device may dissolve over time and pass
harmlessly through the pyloric valve and the digestive system. Any
number of suitable alternatives for removal or passage of the
device are possible in various embodiments.
[0093] FIGS. 11A and 11B show top and perspective views,
respectively, of an alternative variation for the device which may
reside solely in the stomach. This particular variation may
incorporate multiple prongs 100, 102, 104, 106, 108, 110 designed
to intermittently cork the pylorus. In this variation, an expansile
material 96 may be appropriately shaped in order to promote
occlusion of the pylorus. The device may be ejected from the
pylorus due to contractions, but may be re-inserted through one of
the various prongs. As a further measure, the device may define
multiple apertures 98 through each set of prongs to prevent
complete obstruction of the pyloric valve.
[0094] FIGS. 12A and 12B show side and top views, respectively, of
another variation of A device as in FIGS. 11A and 11B. In this
variation, a fewer number of multiple prongs 112, 114, 116, 118 may
be utilized and each prong may also define an aperture 120
therethrough. However, as shown in this variation, each of the
prongs may be flexible and tapered or rounded to prevent damage to
the surrounding tissue.
[0095] FIGS. 13A to 13D show cross-sectional views of an
alternative use of the devices described herein. In this variation,
the device may be utilized in the prevention of gastroduodenal
reflux during tube feeding. As shown, the device 124 is similar to
variations described above; however, in this variation, a lumen 132
defined through the device 124 for tube feed delivery may define an
outlet 134 designed to be positioned in the duodenum 76. The
proximal portion of the device 124 may also be attached to a
feeding tube 126 and an inflation tubing 130. Feeding tube 126 may
be used to deliver tube feeds through the lumen 132 directly to the
duodenum 140 while the inflation tubing 130 may be used to inflate
an inflatable pyloric spanner or bridging member 136 during tube
feeding to prevent reflux of delivered material 140. The device 124
can also incorporate a third tube 128 which may provide for
aspiration of the gastric contents 138 to prevent reflux of the
delivered material into the lungs and to decompress the stomach 74.
The proximal portion of the occlusive member can either maintain
its inflated or expanded state or it can be decompressed at times
to relieve pressure on the pyloric valve. In this variation, a
percutaneous approach is shown, but a nasogastric approach or
another approach is possible.
[0096] FIGS. 14A to 14D show cross-sectional views of yet another
alternative use of devices of the present invention. As shown in
FIGS. 14A to 14C, a device 90 may be placed to occlude the pyloric
valve. In this case, the device 90 is shown as having been
ingested, although placement of the device 90 may be affected via
any of the methods described above. As shown in FIG. 14D, the
addition of one or several gastric fillers 142, e.g., inflatable
gastric balloons, expandable scaffolding, or any other number of
space-occupying devices generally known in the art, may be
utilized. In this variation, the device 90 may be placed and then
the gastric fillers 142 may be introduced. The device 90 may be
utilized to ensure that the gastric fillers 142 are not passed
through the pyloric valve until they are sufficiently small,
thereby allowing for non-degradable substances to be utilized
without the concomitant risk of small bowel obstruction.
[0097] FIGS. 15A to 15 D are cross-sectional views demonstrating
the use of another embodiment of a device 150 for intermittently
obstructing a pyloric valve 156, and in this embodiment for
partially filling the gastric space. FIG. 15A illustrates the
device 150 in an unexpanded or uninflated state and ready for
delivery and/or insertion into the stomach via a catheter device
152, such as an endoscope, tubing or the like. The device, in this
embodiment, includes an expandable foam 154, which is expanded when
the device 150 is within the stomach, as shown in FIG. 15B. Any
suitable nontoxic liquids or gases may be introduced through an
inflation port 158, for expanding the device 150 and/or the foam
154.
[0098] Any suitable materials may be used to form the device 150.
In one embodiment, for example, the device 150 may comprise an
expandable balloon fabricated from silicone, silicone elastomers,
latex, polyurethane, PTFE, FEP, and/or the like. The
internalinflatable lumen of the balloon can be filled with an
expansile cohesive material such as a dehydrated and crosslinked
PEG, a dehydrated hydrogel, or other swellable mass, or buttressed
with a shape memory material such as a shape memory foam, shape
memory metals (such as Nitinol), or shape memory polymers. The
buttressing materials can be placed anywhere on the device,
including inside the flexible balloon material. Alternatively, the
wall of the balloon itself can be composed of a shape memory
material, obviating the need for any filling or buttressing. If
self-expanding materials are utilized, they may be disposed inside
the balloon, and the balloon may be infused with a fluid such as
saline to expand the materials.
[0099] As shown in FIG. 151B, the device 150 in one embodiment
includes a proximal portion 153 and a distal portion 155. In some
embodiments, the proximal portion 153 has a supportive or
structural function, for assuring that the device 150 has a large
enough cross sectional diameter to prevent passage of the device
150 through the pyloric valve. Typically, the distal portion 155
functions to contact the pyloric valve 156 and/or tissue adjacent
the pyloric valve 156, to intermittently and/or partially block the
valve 156. In some embodiments, the distal portion 155 is made of
compliant material, so that when it contacts stomach tissue in,
around or adjacent the pyloric valve 156, it does not harm the
tissue. In some embodiments the proximal portion 153 and distal
portion 155 are made of the same material, with the proximal
portion 153 having a greater amount of material, greater wall
thickness or the like, relative to the distal portion 155.
[0100] Generally, the device 150 may have any of a number of
suitable shapes, such as an irregular oblong shape as shown, an
elongated spherical shape, a cone, a diamond or the like. In some
embodiments, the shape is selected such that the device 150
naturally migrates toward the pyloric valve 156, with the distal
portion 155 aligned to contact the valve 156. In these and other
embodiments, migration of the device 150 to the valve 156 may be
further enhanced by selecting a specific gravity or buoyancy of the
device to allow it to move through the stomach contents towards the
valve 156.
[0101] FIGS. 15C and 15D the distal portion 155 of the device 150
in interacting with the pyloric valve 156. As illustrated, the
shape of the distal portion 155 is configured to move out of (FIG.
15C) and into (FIG. 15D) contact with the valve 156. This typically
occurs during the natural contractions of the stomach, thus
providing for intermittent obstruction of the pyloric valve 156.
Intermittent obstruction of the pyloric valve 156 causes food in
the stomach to be retained longer, and thus, feelings of satiation
may be initiated sooner and may last longer, leading the patient to
consume less food. In the embodiment shown in FIGS. 15C and 15D,
the distal portion 155 fully obstructs the valve 156 when it is in
contact. In alternative embodiments, the distal portion 155 may not
fully obstruct the valve 156 and may have any of a number of
various configurations designed to allow partial flow even when
fully contacting the pyloric valve 156. For example, the distal
portion 155 may have a shape such as conical, ellipsoid, spherical,
pyramidal, tubular, disc-shaped with a protruding member (designed
to fit within the pylorus) or the like. In one embodiment, the
distal portion 155 and the proximal portion 153 have identical or
nearly identical shapes, so that either end may obstruct the
pyloric valve 156, regardless of the orientation of the device
150.
[0102] The device 150 may have any of a number of additional
features for enhancing its delivery into the stomach, it ability to
intermittently obstruct the pyloric valve 156, its removal from the
stomach and/or the like. In one embodiment, for example, the device
150 includes one or more radiopaque markers, dyes and/or materials
for facilitating visualization of the device 150. The device 150
may also include other markers, dyes or materials that enhance its
visibility to the naked eye, which may be advantageous in
embodiments where the device 150 dissolves and passes through the
body or as a safety feature in the unlikely event that the device
150 breaks or ruptures.
[0103] In some embodiments, the device 150 may include one or more
mechanisms for releasing one or more drugs into the stomach or
small intestine beyond the pyloric valve. For example,
slow-releasing drugs may be coupled with or infused into materials
covering the device 150 or materials used to construct the device
150. These drugs, which may be any of a number of therapeutic or
diagnostic agents, may slowly infuse into the patient by drug
release into the intestinal tract or through contact with the
patient. In other embodiments, the device 150 may incorporate
electrical stimulation technologies. For instance, electrical
probes may extend from a surface of the device 150 for insertion
into the surrounding tissue or electrodes may be formed over a
surface of the device 150.
[0104] In one embodiment, the device 150 may be covered by an
erodable or biodegradable covering for delivery into the stomach.
Such a covering may be configured to constrain the device 150, and
once the covering comes into contact with substances in the gastric
lumen, it may naturally break down and dissolve, thus releasing the
device 150 and allowing it to expand. In one embodiment, the device
150 may be covered by different materials each configured to erode
at differing rates or in different chemical environments within the
stomach.
[0105] FIG. 16 illustrates the device 150 of FIGS. 15A to 15D, in
which a rupture 157 has occurred. As demonstrated by this figure,
the overall shape of the device 150 is maintained due to expanded
foam 154 (or other framework material or the like within or on the
device 150 in other embodiments). Generally, the foam or framework
material will be acid-resistant in order to prevent its degradation
within the stomach and thus allow it to support the device 150 for
extended periods of time after rupture has occurred. In an
alternative embodiment, the foam 154 or other framework material
may degrade slowly after rupture while releasing a signaling
material that would alert the patient to the rupture upon
examination of feces. The patient would then know to consult his
physician to have the device 150 removed.
[0106] Referring now to FIGS. 17A and 17B, another embodiment of a
pyloric valve obstructing device 160 may include and inflation port
168, a proximal portion 163, a distal portion 165, a positioning
member 161 and a retaining member 162. Inflation port 168 is
optional, of course, since some embodiments require inflation while
others do not. Positioning member 161 generally helps position the
device 160 in a location for intermittently obstructing the pyloric
valve 156. Retaining member 162 helps maintain the location or
position of the device 160.
[0107] In one embodiment, the positioning member 161 may be hollow,
thus allowing for passage of fluids and/or gases through the device
to allow the proximal portion 163, distal portion 165 and retaining
member 162 to be inflated. In one embodiment, positioning member
161 may be relatively short, to inhibit movement of the distal
portion 165 relative to the pylorus 156. In other embodiments, the
positioning member 161 may be longer to allow for more movement of
the device 160.
[0108] Referring now to FIG. 17B, in another embodiment a device
170 having proximal 173 and distal 175 portions is coupled with a
positioning member 171 that includes an inflation port 172 at its
distal end. In this embodiment, the device 170 is passed to the
stomach in its uninflated state, the positioning member 171 and
port 172 are used to inflate the device 170, and the positioning
member is then swallowed and passes through the pyloric valve 156
to remain harmlessly in the first part of the small intestine. In
another embodiment, the device may be placed into the stomach while
attached to a removable tether that extends up the esophagus and
into the mouth. The tether can be used to remove the device if it
does not properly deploy, or alternatively it can be detached from
the device once it is in place in the stomach.
[0109] As illustrated in FIGS. 18A and 18B, and as mentioned
earlier, various embodiments of a device for obstructing a pyloric
valve may include any of a number of different expandable support
mechanisms. The embodiments just described included foam, but other
supportive structures and materials may be used, such as
self-expanding cages, coils, lattices, frameworks or the like. In
FIG. 18A, a device 180 having proximal 183 and distal 185 portions
as well as an inflation port 188 also includes an expanding
scaffolding 184, which may be coupled with the wall of the device
180 on its inner surface or outer surface, or which may be embedded
in the wall. Such an expanding scaffolding 184 may be composed of
shape memory or super-elastic materials, such as Nitinol. The
scaffold 184 may be compressed into a delivery configuration and
then either allowed to expand into the desired occlusive shape by
self-expansion or expanded by supplying an activation energy, such
as, electrical energy, heat, RF energy or the like. In another
embodiment, the scaffold may be deployed by pulling the scaffold
into an expanded configuration with a pulling device, and in such
embodiments the scaffold may have a catch mechanism to prevent it
from collapsing to its original shape.
[0110] In the embodiment shown in FIG. 18B, a device 190 includes a
proximal portion 193, a distal portion 195 and an inflation port
198. In this embodiment, a wall 194 of the device 190 is made of a
shape memory, super-elastic or otherwise self-expanding material,
which expands from a smaller configuration to a larger
configuration upon release from constraint. The material of the
wall 194 then retains its expanded shape, thus maintaining the
shape of the device 190 and preventing the device from
collapsing.
[0111] Referring to FIGS. 19A and 19B, another embodiment of a
pyloric valve obstructing device 200 includes a movable or
"inverted" outer shell 204, an inner core 202, a positioning member
208 and a distal retaining member 210 having a hole 212 or other
surface feature. The device 200 is shown in its expanded
configuration in FIG. 19A, for intermittently obstructing a pyloric
valve, and in its collapsed configuration in FIG. 19B, for delivery
into the stomach. The shell 204 includes a tissue
contacting/engaging portion 205 and a support portion 206.
Generally, the support portion 206 is more rigid/stiffer than the
tissue contact portion 205, so that the former helps maintain the
cross-sectional diameter of the device 200 so that it cannot pass
through the pylorus, while the latter is more compliant so that it
can contact stomach tissue without causing significant damage.
[0112] The various components of the device 200 may be constructed
of any suitable materials, such as those already described or any
other suitable materials now known or hereafter discovered. In one
embodiment, the inner core 202 is a solid material, such as
silicone, but in other embodiments the core 202 may be hollow. The
core 202 may have any suitable size, shape, cross-sectional
diameter or the like. In one embodiment, the core 202 has a
cross-sectional diameter of between about 5 mm and about 30 mm, and
preferably about 10 mm. The shell 204 may be made of the same or
different material as the core 202, and also may have any suitable
size, shape, cross-sectional diameter or the like. In one
embodiment, the support portion 206 of the shell 204 is thicker
that the tissue contact portion 205. In other embodiments, the
support portion 206 may be made of a different material than the
tissue contact portion 205.
[0113] The positioning member 208 may be an extension of inner core
202, shell 204 or both, or may instead be a separate piece coupled
with the inner core 202 and/or outer shell 204. Positioning member
208 may have any suitable length and diameter to allow it to pass
through the pyloric valve. In one embodiment its cross-sectional
diameter is about 1.0 cm or less and its length is about 3.0 cm or
greater. The retaining member 210 may also have any suitable size,
shape or configuration, with some embodiments being expandable,
some being self-expanding, and others configured to not expand at
all. In one embodiment, the retaining member 210 has a greatest
cross-sectional diameter of about 30 mm or smaller, and preferably
about 25 mm or smaller, and even more preferable about 21 mm or
smaller. The hole 212 or surface feature in the retaining member
210 may have any configuration for allowing coupling of an actuator
or other device with the retaining member for delivering, adjusting
and/or retrieving the device 200. Both the positioning member 208
and the retaining member 210 may be made of any suitable
material.
[0114] Although not drawn to scale, FIG. 19B illustrates the
collapsed or inverted state of the device 200. In this
configuration, the shell 204 may be compressed to a smaller
cross-sectional diameter for delivery, such as through a delivery
tube or catheter. After the device 200 is delivered to the stomach,
the shell 204 is inverted to its expanded state and the device 200
may then act to intermittently obstruct the pyloric valve.
[0115] FIGS. 20A to 20C illustrate a method for delivering and
deploying the device 200 of FIGS. 19A and 19B in a stomach. In FIG.
20A, the device 200 is housed within the lumen of a delivery tube
214 or catheter in its collapsed configuration. In FIG. 20B, the
device has been advanced partially out of the delivery tube,
allowing the shell 204 to at least partially expand. An actuator
216 hooked through the hole 212 on the retaining member 210 may
then be used to pull back on the device 200, such that the shell
204 overlaps the distal end of the delivery tube 214. The distal
end of the delivery tube 204 is then used to apply force to the
shell 204, causing it to invert into its expanded state, as shown
in FIG. 20C. As also shown in FIG. 20C, the actuator 216 may
include a hook 218 for coupling with the hole 212 in the retaining
member 210. Once the shell 204 is moved to its expanded
configuration, it is designed to stay in that configuration, thus
providing the pyloric valve contacting and device retention
functions described above. In one embodiment, the delivery tube 214
may include an expandable balloon (not shown) at or near its distal
end. The balloon maybe doughnut-shaped to inflate
circumferentially, or may be have an eccentric shape or any other
suitable shape. The balloon may be inflated and serve as a stop
against which the device 200 may be pulled. Alternatively, the
balloon may be inflated under or within the device 200 to invert
the device 200 as the balloon inflates.
[0116] In other embodiments, the device may be delivered and/or
deployed using any other suitable method. For example, in one
embodiment the shell 204 may "self-invert" from its
constrained/collapsed state to its expanded state without using an
actuator 216 or the distal end of a delivery device 214.
Self-inverting may be achieved by shape-memory or spring loaded
materials or the like, or by a shell geometry that creates a bias
in the stiffness of the device. In another embodiment, the device
200 may be swallowed, either in a folded or otherwise collapsed
state or housed within a dissolving caplet. A number of different
alternative embodiments are possible.
[0117] FIGS. 21A and 21B are show the introduction and expansion of
one variation of the device. In FIG. 21A, the balloon 251 is
introduced by endoscopy tubing 252 in an unexpanded or uninflated
state. Inside the balloon is a shape memory foam 253. In FIG. 21B,
the balloon 251 is fully inserted and the shape memory foam 253 is
expanded according to its shape memory. As noted above, the balloon
can be fabricated from silicon, silicon elastomers, latex,
polyurethane, PTFE, FEP, or other materials. The interior of the
balloon can be a self-expanding material such as a foam or hydrogel
that expands upon contact with fluids, such as saline.
Alternatively, the balloon can be expanded by being filled with any
nontoxic liquid or gas, through an inflation port 254. The distal
occlusive portion 255 of the balloon will occlude the pyloric valve
256.
[0118] In FIGS. 22A and 22B, the occlusion portion 255 is shown in
two successive positions moving into engagement with the pyloric
valve 256. A visible dye or marker, preferably one that is highly
visible, can be infused into the balloon 251 as a safety measure.
Alternatively, the balloon itself can be fabricated from a material
that is highly visible and visually distinct from tissue so that in
the unlikely event of a rupture of the balloon, the due or pieces
of the balloon will become visible as they pass from the body,
indicating to the patient or to a physician that a rupture has
occurred.
[0119] The balloon can also be covered by an erodible or
biodegradable covering that will constrain the balloon until the
balloon is ingested or placed within the gastric lumen where the
gastric fluids will erode the covering and thereby allow the
balloon to expand or inflate. The balloon can also be covered with
materials that are configured to erode at differing rates or in
different environments.
[0120] In FIG. 3, a rupture 261 has occurred in the balloon 253 and
yet the profiled of the balloon is maintained due to the shape
memory foam or expansile internal material retained inside the
balloon. The foam or material is preferably acid-resistant to
prevent degradation and allow it to support the balloon wall for
extended periods of time following rupture. Alternatively, the
balloon filling could degrade slowly after rupture with release of
a signaling material to alert the patient to its rupture upon
examination of feces.
[0121] In FIG. 24A, a pylorus-spanning tether 271 is attached to
the balloon, and a distal occluding member 272 is attached to the
opposite end of the tether 271. The tether 271 holds the distal end
273 of the balloon 274 near the pylorus to urge the balloon toward
the position in which it obstructs the pylorus. A relatively short
tether 271 will limit the range of movement of the occlusive
(distal) end 273 of the balloon relative to the pylorus.
[0122] In FIG. 24B, the balloon 281 has a tether 282 attached to
its distal end 283 and an inflation port 284 at the distal end of
the tether 282. To utilize this device, the balloon 281 is
swallowed without swallowing the inflation port 284, leaving the
inflation port inside the patient's mouth. Once the balloon has
been inflated through the inflation port, the patient can simply
ingest the tether 282 which will eventually migrate across the
pyloric valve 285 and help hold the distal end 283 of the balloon
in the region of the pyloric valve.
[0123] Further variations are shown in FIGS. 25A and 25B. In FIG.
25A, the balloon 291 contains internal expandable caging 292 to
establish its shape, while in FIG. 25B, the balloon 293 contains an
outer shell 294 made of a shape memory material.
[0124] A still further variation on the device and its use are
shown in FIGS. 26A, 26B, and 26C. The device in these figures is a
shape-memory component 301 such as a resilient lattice or cage,
with a functional component 302 held inside. In its relaxed
position, the shape-memory component 301 is large in volume, shown
here as a sphere (FIG. 26A), that cannot pass through the pylorus
and is therefore retained in the stomach but of open structure to
avoid any interference with the flow of digested matter from the
stomach through the pylorus into the intestine. The shape-memory
component 301 can also be elongated to a deformed position, as
shown in FIG. 26C, by applying and maintaining a longitudinal
extension force to the component. In this deformed position, the
device can be inserted into the stomach through the esophagus. The
functional component 302 fits inside the shape-memory component 301
in both the relaxed and elongated conformations of the shape-memory
component. The functional component 302 is either a drug pump, a
gastric stimulator, or any other delivery or otherwise therapeutic
device. Manipulation of the shape-memory component 301 is achieved
by an endoscopic tool 303 that contains an internal extension rod
304 that can be moved forward and back relative to the tool by
standard external means (not shown) that are common and known for
endoscopy tools. The distal ends of both the endoscopy tool 303 and
the extension rod 304 can be fitted with grasping components such
as forceps, a snare, or the like. To insert the device into the
stomach of a patient, a physician will mount the device to the
distal end of the endoscopy tool, with the distal end of the tool
attached to the proximal end of the shape memory device 301 and the
distal end of the internal rod attached to the proximal end of the
functional component 302. The physician will then extend the rod
304 to elongate the shape memory component 301 as in FIG. 26C,
thereby reducing its diameter so that the entire device can be
inserted into the stomach. Once inserted, the rod 304 is retracted
by the physician, through an intermediate configuration as in FIG.
26B to a relaxed configuration as in FIG. 26A. Removal of the
device from the stomach is achieved by the reverse procedure, i.e.,
the endoscopy tool 303 with retracted rod 304 is inserted into the
stomach (through the esophagus) and once inserted, its grasping
components are manipulated to engage the components of the device.
Once these components are engaged, the rod is extended, causing
elongation and deformation of the shape memory component and
thereby enabling removal of the entire device from the stomach.
[0125] In a further variation on the device pictured in FIGS. 26A,
26B, and 26C, the shape-memory component 301 is replaced with a
relatively flexible cage of the same configuration, either without
a shape memory or with a shape memory that is less than fully
realized after distortion. The distal end 305 of the cage is joined
to the distal end 306 of the functional component, while the
proximal ends 307, 308, respectively, are joinable but detachable,
i.e., reversibly joinable. When the proximal ends 307, 308 are
joined, as shown in FIG. 26A, the cage 301 is fixed in the
configuration shown and thereby retainable in the stomach due to
its large diameter. When the proximal ends are detached, the cage
301 and functional component 302 are removable, insertable, or
generally capable of manipulation. Engagement and disengagement of
the proximal ends can be achieved by endoscopy tools, such as
forceps, gasping elements for twisting, or cutting elements. In
certain embodiments, labels that are detectable and capable of
being monitored from outside the body are affixed to the proximal
end of the functional device 302, the cage 301, or both, to
facilitate the manipulations.
[0126] In still further embodiments, the shape memory component or
flexible cage 301 is useful by itself, i.e., without the presence
of an additional functional component 302, as a space-occupying
device to reduce the volume in the stomach. This serves as a means
of weight reduction by reducing the volume of food that can be
retained in the stomach and thereby the volume that can be absorbed
through the stomach walls.
[0127] Although the above is a complete and accurate description of
the invention, any of a number of variations, additions and the
like may be made to the embodiments described without departing
from the scope of the invention. For example, devices and methods
described above are not limited strictly to treatment of obesity,
but may also be used to treat other conditions. Furthermore, other
devices, such as imaging devices, chemical detection devices, space
occupying devices and/or the like may be incorporated into many of
the embodiments described above without departing from the scope of
the invention. Therefore, the foregoing description is provided
primarily for exemplary purposes and should not be interpreted to
limit the scope of the invention as it is defined in the following
claims.
* * * * *