U.S. patent application number 13/666919 was filed with the patent office on 2013-05-02 for duodenal gastrointestinal devices and related treatment methods.
The applicant listed for this patent is Kenneth F. BINMOELLER, John P. LUNSFORD, James T. MCKINLEY, Nam Q. NGUYEN, Hoang G. M. PHAN, Fiona M. SANDER, Christopher THORNE. Invention is credited to Kenneth F. BINMOELLER, John P. LUNSFORD, James T. MCKINLEY, Nam Q. NGUYEN, Hoang G. M. PHAN, Fiona M. SANDER, Christopher THORNE.
Application Number | 20130109912 13/666919 |
Document ID | / |
Family ID | 48173073 |
Filed Date | 2013-05-02 |
United States Patent
Application |
20130109912 |
Kind Code |
A1 |
BINMOELLER; Kenneth F. ; et
al. |
May 2, 2013 |
DUODENAL GASTROINTESTINAL DEVICES AND RELATED TREATMENT METHODS
Abstract
An intragastric device includes an elongated member having a
proximal end and a distal end and an anchor connected to the
elongated member. The anchor includes a stem, a first arch and a
second arch, and a curvilinear element. The stem includes a
proximal end and a distal end. The distal end of the stem is
attached to the proximal end of the elongated member. Each arch has
first and second ends and a proximal peak therebetween. The first
end of each arch is attached to the proximal end of the stem, and
the second end of each arch extends radially away from the stem.
The curvilinear element connects the second end of the first arch
to the second end of the second arch.
Inventors: |
BINMOELLER; Kenneth F.;
(Rancho Santa Fe, CA) ; MCKINLEY; James T.;
(Redwood City, CA) ; SANDER; Fiona M.; (Los Altos
Hills, CA) ; LUNSFORD; John P.; (San Carlos, CA)
; PHAN; Hoang G. M.; (Fremont, CA) ; THORNE;
Christopher; (Columbus, OH) ; NGUYEN; Nam Q.;
(Adelaide, AU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BINMOELLER; Kenneth F.
MCKINLEY; James T.
SANDER; Fiona M.
LUNSFORD; John P.
PHAN; Hoang G. M.
THORNE; Christopher
NGUYEN; Nam Q. |
Rancho Santa Fe
Redwood City
Los Altos Hills
San Carlos
Fremont
Columbus
Adelaide |
CA
CA
CA
CA
CA
OH |
US
US
US
US
US
US
AU |
|
|
Family ID: |
48173073 |
Appl. No.: |
13/666919 |
Filed: |
November 1, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61554429 |
Nov 1, 2011 |
|
|
|
61647396 |
May 15, 2012 |
|
|
|
61699172 |
Sep 10, 2012 |
|
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Current U.S.
Class: |
600/37 |
Current CPC
Class: |
A61F 5/0079 20130101;
A61F 5/0076 20130101 |
Class at
Publication: |
600/37 |
International
Class: |
A61F 2/02 20060101
A61F002/02 |
Claims
1. An intragastric device comprising: an elongated member having a
proximal end and a distal end; and an anchor connected to the
elongated member, the anchor comprising: a stem having a proximal
end and a distal end, the distal end of the stem attached to the
proximal end of the elongated member; a first arch and a second
arch, each arch having first and second ends and a proximal peak
therebetween, the first end of each arch attached to the proximal
end of the stem, and the second end of each arch extending radially
away from the stem; and a curvilinear element connecting the second
end of the first arch to the second end of the second arch.
2. The intragastric device of claim 1, wherein the stem, the first
arch, the second arch, and the curvilinear element are formed from
a single piece of wire.
3. The intragastric device of claim 2, wherein the elongated member
is formed from the same single piece of wire.
4. The intragastric device of claim 1, wherein the curvilinear
element includes at least one coil that loops around and
substantially perpendicular to the stem.
5. The intragastric device of claim 4, wherein the coil forms at
least one complete loop around the stem.
6. The intragastric device of claim 4, wherein a distance between
the second end of the first arch and the second end of the second
arch is greater than a diameter of the coil.
7. The intragastric device of claim 1, wherein the second end of
the first arch curves in the same clockwise or counterclockwise
direction as the second end of the second arch.
8. The intragastric device of claim 1, wherein the first arch and
second arch extend in substantially opposite radial directions.
9. The intragastric device of claim 1, wherein the curvilinear
element includes a pull loop extending proximal to the proximal end
of the stem and between the first and second arches.
10. The intragastric device of claim 9, wherein the pull loop is
configured such that, when the pull loop is moved proximally away
from the stem, the curvatures of the first arch and the second arch
are reduced.
11. The intragastric device of claim 1, wherein the curvilinear
element includes at least one counterarch, the at least one
counterarch having a distal peak.
12. The intragastric device of claim 1, wherein, in use within the
gastrointestinal tract, the diameter of the anchor is larger than
an opening through which the elongated member passes.
13. The intragastric device of claim 12, wherein the opening is a
pylorus.
14. The intragastric device of claim 1, wherein the arches and
curvilinear element are configured to be unwound to form a
straightened anchor for delivery or removal of the anchor from the
gastrointestinal tract.
15. The intragastric device of claim 14, wherein the straightened
anchor comprises two substantially parallel and straight wires for
delivery or removal.
16. The intragastric device of claim 1, further comprising a
fastening element configured to fasten at least one portion of the
anchor to another portion of the anchor to hold the shape of the
anchor during use in the gastrointestinal tract.
17. A method of anchoring a treatment device within the stomach,
the method comprising: advancing the treatment device through the
pylorus and into position within the gastrointestinal tract;
positioning an anchor connected to the device in the stomach in a
stowed configuration; and expanding the anchor from the stowed
configuration into a deployed configuration, the deployed
configuration having a stem with a first arch and a second arch
radially extending therefrom, the anchor in the deployed
configuration having a diameter that is larger than the diameter of
the pylorus.
18. The method of claim 17, wherein, in the stowed configuration,
the anchor comprises two substantially parallel and straight wires,
the substantially parallel and straight wires forming the first and
second arches in the deployed configuration.
19. The method of claim 17, further comprising pulling proximally
on a portion of the anchor in the deployed configuration to
collapse the anchor back to the stowed configuration.
20. The method of claim 17, wherein the portion of the anchor is a
pull loop connected to the arches.
21. The method of claim 20, wherein the anchor further comprises a
curvilinear element connecting the first and second arches
together.
22. The method of claim 21, wherein pulling proximally on the pull
loop causes the curvilinear element to move proximally past the
first and second arches and pull the first and second arches
substantially straight.
23. The method of claim 17, further comprising locking the anchor
in the deployed configuration with a fastening mechanism.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to the following
applications: U.S. Provisional Patent Application No. 61/554,429,
filed Nov. 1, 2011 of Binmoeller et al., entitled "DUODENAL
GASTROINTESTINAL DEVICES AND RELATED TREATMENT METHODS;" U.S.
Provisional Patent Application No. 61/647,396, filed May 15, 2012
of Binmoeller et al., entitled "DUODENAL GASTROINTESTINAL DEVICES
AND RELATED TREATMENT METHODS;" and U.S. Provisional Patent
Application No. 61/699,172, filed Sep. 10, 2012 of Binmoeller et
al., entitled "DUODENAL GASTROINTESTINAL DEVICES AND RELATED
TREATMENT METHODS."
INCORPORATION BY REFERENCE
[0002] All publications, patents and patent applications mentioned
in this specification are herein incorporated by reference to the
same extent as if each individual publication, patent or patent
application was specifically and individually indicated to be
incorporated by reference.
FIELD
[0003] The invention is in the field of medical devices that reside
within a lumen of the gastrointestinal tract and provide a platform
for medical applications. More particularly, embodiments of the
invention stabilize at a luminal residence site by virtue of their
physical conformation.
BACKGROUND
[0004] Obesity, defined as a body mass index (BMI) of greater than
30, is a major health concern in the United States and other
countries; it has been estimated that one in three Americans and
more than 300 million people world-wide are obese. Complications of
obesity include many serious and life-threatening diseases
including hypertension, diabetes, coronary artery disease, stroke,
congestive heart failure, pulmonary insufficiency, multiple
orthopedic problems, various cancers and a markedly decreased life
expectancy. Intentional weight loss, however, can improve many of
these medical complications associated with obesity.
[0005] While weight loss can improve many of the medical
complications associated with obesity, its management as a health
concern has proven troublesome. A variety of approaches including
dietary methods, psychotherapy, behavior modification, and
pharmacotherapy have each met with some success but as a whole
failed to effectively control the rapid growth in the incidence and
severity of obesity seen in the United States. The severity of
problems associated with obesity also has led to the development of
several drastic surgical procedures. One such procedure physically
reduces the size of the stomach so that a person cannot consume as
much food as was previously possible. These stomach reduction
surgeries had limited early success, but now it is known that the
stomach can stretch back to a larger volume over time, limiting the
achievement of sustained weight loss in many individuals. Another
drastic surgical procedure induces the malabsorption of food by
reducing the absorptive surface of the gastrointestinal (GI) tract,
generally via by-passing portions of the small intestine. This
gastric by-pass procedure further has been combined with stomach
reduction surgery. While these described surgical procedures can be
effective to induce a reduction in food intake and/or overall
weight loss in some, the surgical procedures are highly invasive
and cause undue pain and discomfort. Further, the described
procedures may result in numerous life-threatening postoperative
complications. These surgical procedures are also expensive,
difficult to reverse, and place a large burden on the national
health care system.
[0006] Non-surgical approaches for the treatment of obesity also
have been developed. For example, one non-surgical endoscopic
approach to treating obesity includes the placement of a gastric
balloon within the stomach. The gastric balloon fills a portion of
the stomach, providing the patient with a feeling of fullness,
thereby reducing food intake. This approach has yet to be
convincingly shown to be successful, and a number of problems are
associated with the gastric balloon device, however, including poor
patient tolerance and complications due to rupture and/or migration
of the balloon. Other non-surgical devices designed to induce
weight loss limit the absorption of nutrients in the small
intestine by funneling food from the stomach into a tube found
within the small intestine so that the food is not fully digested
or absorbed within the small intestine. While this type of device
may be somewhat effective at limiting the absorption of consumed
food, there is still room for a variety of improvements in
non-surgical devices designed to induce weight loss and/or a
reduction in food intake.
[0007] An understanding of biological events that contribute to the
creation of satiety signals provides an opportunity to develop
"smart" nonsurgical devices that can trigger such events. The
amount of food that individuals consume is largely dependent on
biological signals between the gut and the brain. Specifically,
hormonal signals from the gut to the brain are correlated with both
the onset and cessation of food intake. While increased levels of
hormones such as ghrelin, motilin and agouti-related peptide are
involved in the promotion of appetite and the onset of food intake,
increased levels of a number of other hormones are involved in the
cessation of food intake.
[0008] Various biologic events contribute to the physiologic
cessation of food intake. Generally, as a meal is consumed, the
ingested food and by-products of digestion interact with an array
of receptors along the GI tract to create satiety signals. Satiety
signals communicate to the brain that an adequate amount of food
has been consumed and that an organism should stop eating.
Specifically, GI tract chemoreceptors respond to products of
digestion (such as sugars, fatty acids, amino acids and peptides)
while stretch receptors in the stomach and proximal small intestine
respond to the physical presence of consumed foods. Chemoreceptors
respond to the products of digestion by causing the release of
hormones or other molecular signals. These released hormones and/or
other molecular signals can stimulate nerve fibers to send satiety
signals to the brain. The arrival of these signals in the brain can
trigger a variety of neural pathways that can reduce food intake.
The released hormones and/or other molecular signals can also
travel to the brain themselves to help create signals of satiety.
Mechanoreceptors generally send satiety signals to the brain
through stimulation of nerve fibers in the periphery that signal
the brain. The present invention provides methods and devices that
help to reduce food intake by providing non-surgical devices and
methods that trigger the aforementioned biological events that
contribute to the creation of satiety signals.
SUMMARY OF THE DISCLOSURE
[0009] Described herein are intragastric devices.
[0010] In general, in one embodiment, an intragastric device
includes an elongated member having a proximal end and a distal end
and an anchor connected to the elongated member. The anchor
includes a stem, a first arch and a second arch, and a curvilinear
element. The stem includes a proximal end and a distal end. The
distal end of the stem is attached to the proximal end of the
elongated member. Each arch has first and second ends and a
proximal peak therebetween. The first end of each arch is attached
to the proximal end of the stem, and the second end of each arch
extends radially away from the stem. The curvilinear element
connects the second end of the first arch to the second end of the
second arch.
[0011] This and other embodiments can include one or more of the
following features. The stem, the first arch, the second arch, and
the curvilinear element can be formed from a single piece of wire.
The elongated member can be formed from the same single piece of
wire. The curvilinear element can include at least one coil that
loops around and substantially perpendicular to the stem. The coil
can form at least one complete loop around the stem. The distance
between the second end of the first arch and the second end of the
second arch can be greater than the diameter of the coil. The
second end of the first arch can curve in the same clockwise or
counterclockwise direction as the second end of the second arch.
The first arch and second arch can extend in substantially opposite
radial directions. The curvilinear element can include a pull loop
extending proximal to the proximal end of the stem between the
first and second arches. The pull loop can be configured such that,
when the pull loop is moved proximally away from the stem, the
curvature of the first arch and the second arch are reduced. The
curvilinear element can include at least one counterarch, and the
counterarch can have a distal peak. In use within the
gastrointestinal tract, the diameter of the anchor can be larger
than an opening through which the elongated member passes. The
opening can be a pylorus. The arches and curvilinear element can be
configured to be unwound to form a straightened anchor for delivery
or removal of the anchor from the gastrointestinal tract. The
straightened anchor can include two substantially parallel and
straight wires for delivery or removal. The device can further
include a fastening element configured to fasten at least one
portion of the anchor to another portion of the anchor to hold the
shape of the anchor during use in the gastrointestinal tract.
[0012] In general, in one embodiment, a method of anchoring a
treatment device in the stomach includes: advancing the treatment
device through the pylorus and into position within the
gastrointestinal tract; positioning an anchor connected to the
device in the stomach in a stowed configuration; and expanding the
anchor from the stowed configuration into a deployed configuration.
The deployed configuration has a stem with a first arch and a
second arch radially extending therefrom. The anchor in the
deployed configuration has a diameter that is larger than the
diameter of the pylorus.
[0013] This and other embodiments can include one or more of the
following features. In the stowed configuration, then anchor can
include two substantially parallel and straight wires, and the
substantially parallel and straight wires can form the first and
second arches in the deployed configuration. The method can further
include pulling proximally on a portion of the anchor in the
deployed configuration to collapse the anchor back to the stowed
configuration. The portion of the anchor can be a pull loop
connected to the arches. The anchor can further include a
curvilinear element connecting the first and second arches
together. Pulling proximally on the pull loop can cause the
curvilinear element to move proximally past the first and second
arches and pull the first and second arches substantially straight.
The method can further include locking the anchor in the deployed
configuration with a fastening element.
[0014] In an alternative to the embodiments described above, an
anchor may include a single arch. In another alternative
embodiment, the anchor may include single or multiple coils or
loops of wire without any arches.
[0015] Any of the embodiments described above can include one or
more of the following features.
[0016] The device can include a conformationally-stabilized spine.
Flow reduction elements can surround the elongated member. The flow
reduction elements can be formed of an expandable sleeve. The flow
reduction elements and/or the elongated member can include
bioactive materials therein. The distal end of the elongated member
can terminate near the duodenojejunal junction. The anchors can
include a fastener to lock two portions of the anchor together,
such as a cinching mechanism, a ball and spring fastener, and
eyelet and double barbed fastener, a ball and doubled-lumen eyelet
fastener, a helical and multi-ball fastener, an eyelet and post/tab
fastener, a sleeve fastener, or a multi-tabbed and eyelet fastener.
The elongated member can be a floppy cord or tube. The anchor or
elongated member can have shape lock features. The ends of the
device can be bulbous or coiled. The stem can be formed of two
wires that are joined together. The joint between the two wires can
be a sleeve welded to each wire without welding between the two
wires. The joint can include welding between the two wires. The
anchor can be asymmetric with respect to the stem. The anchor can
have a FIG. 8 shape. The anchor can be formed of a single wire
having a break therein. The break can be closed with a fastener.
The device can include a secondary anchor for use in the duodenal
bulb. The device can include a pusher thereon configured to provide
a location for contact during delivery or removal of the
device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a general drawing of the stomach and duodenum of
the small intestine.
[0018] FIG. 2 depicts several exemplary mechanisms through which
satiety signals may be generated.
[0019] FIG. 3 is a perspective view of one embodiment of a
duodenal/small intestinal insert in accordance with the present
invention positioned inside the stomach and small intestine.
[0020] FIG. 4 is a partial section view of a central tube
illustrating attached flow reduction elements and a central
lumen.
[0021] FIG. 5 is a partial section view of a central tube
illustrating eccentrically attached flow reduction elements and a
central lumen.
[0022] FIG. 6 is a perspective view of an alternative embodiment
showing an elongated member and illustrating attached flow
reduction elements.
[0023] FIG. 7 is a perspective section view of a central tube and
an anchoring member.
[0024] FIG. 8 is a perspective view of an alternative embodiment of
a central tube and an anchoring member.
[0025] FIG. 9 illustrates a central tube attached to an expandable
sleeve, the expandable sleeve allowing expansion of particular
segments of the central tube to form flow reduction elements.
[0026] FIG. 10 illustrates an expandable sleeve in a collapsed
configuration for insertion into the small intestine.
[0027] FIG. 11 illustrates one mechanism for keeping flow reduction
elements formed with an expandable sleeve in a desired expanded
configuration.
[0028] FIG. 12 is a flow diagram depicting the intestinal insert's
role in contributing to the generation of one or more signals of
satiety.
[0029] FIG. 13 is perspective view of the duodenum.
[0030] FIG. 14 depicts a side view of the duodenum, showing the
folds of rugae that form the periphery of the inner space within
which embodiments of the insert device are positioned.
[0031] FIG. 15 shows an embodiment of a device that has flow
reduction elements formed from a sleeve and that has proximal
portion that terminates in the gastric antrum; and the distal
portion terminates near the duodenojejunal junction.
[0032] FIGS. 16A and 16B show two devices with a varying amount of
end-end crossover: FIG. 16A depicts a device with a relatively long
separation between ends and a relatively large end-end cross over
dimension. FIG. 16B depicts a device with a relatively short
separation between ends and a relatively small end-end cross over
dimension.
[0033] FIG. 17 shows the device depicted in FIG. 15 in a
gastrointestinal residence site, with the proximal portion
terminating in the gastric antrum, and the distal portion
terminating near the duodenojejunal junction.
[0034] FIG. 18 shows an alternative embodiment of a device similar
to that shown in FIG. 15, with a large single flow reduction
element.
[0035] FIG. 19 shows a section view of the stomach with a device
implanted into the duodenum having an proximal portion extended
beyond the active portion of the stomach;
[0036] FIG. 20 shows a section view of the stomach with another
device implanted into the duodenum having an alternative proximal
portion extended beyond the active portion of the stomach;
[0037] FIG. 21 shows a section view of the stomach with another
device implanted into the duodenum having an proximal portion
extended beyond the active portion of the stomach;
[0038] FIG. 22 shows a section view of the stomach with a device
implanted into the duodenum having an distal portion extending into
the jejunum;
[0039] FIG. 23 shows a section view of the stomach with a device
implanted into the duodenum having an distal portion extending into
the jejunum;
[0040] FIG. 24 shows a section view of the stomach with a device
implanted into the duodenum having an proximal ring shaped
anchor;
[0041] FIG. 25 shows a section view of the stomach with a device
implanted into the duodenum having an enlarged proximal coil;
[0042] FIG. 26A shows a section view of the stomach with a device
implanted into the duodenum having an enlarged proximal coil and a
retaining ring on the coil (seen best in the enlarged view of FIG.
26B);
[0043] FIG. 26C is an alternative fastener and clip for retaining a
coil;
[0044] FIGS. 27A-27D show a device having a shaped proximal portion
and a floppy distal portion including flow reduction elements along
the distal portion (FIG. 27A) having various lengths to place a
terminal end in different locations within the duodenum such as the
duodenojejunal flexure (FIG. 27B), within the jejunum (FIG. 27C) or
within the horizontal or vertical duodenum (FIG. 27D);
[0045] FIGS. 28A-28B show a portion of a device with shape lock
features (FIG. 28A) and with engaged shape lock features confirming
to the shape of the duodenum (FIG. 28B);
[0046] FIG. 29 shows a device within the duodenum having shape lock
features with variable sized links and joints in the shape lock
portions;
[0047] FIGS. 30A-30B illustrate a device with a proximal anchor
formed from a multiple strand ball in a deployed and stowed
configuration, respectively;
[0048] FIGS. 31A-31B illustrate a device with a proximal anchor
formed from a multiple strand ball with a membrane coating in a
deployed and stowed configuration, respectively;
[0049] FIGS. 32A, 32B and 32C are various views of a proximal
anchor embodiment having a stem, a single arch, a coil and
terminating in a curved or coiled section;
[0050] FIG. 33 is a cross section view of the stomach with a device
having a stem, arch and coils similar to FIGS. 32A-32C with the
substitution of a bulbous terminal end instead of or in addition to
the small coiled end of FIGS. 32A-32C; and
[0051] FIGS. 34A, 34B and 34C are various views of a proximal
anchor embodiment having a dual shaft stem and a pair of arches
leading to counter wound coils.
[0052] FIGS. 35A-35D are views of a proximal anchor embodiment
having a pair of arches leading to counter wound coils and a pull
loop extending between the arches for anchor removal.
[0053] FIGS. 36A and 36B are views of a portion of a proximal
anchor where distal ends of the arches of the proximal anchor have
been flattened at the joint between the two arches. FIGS. 36C-36E
are views of a portion of a proximal anchor where the distal end of
an arch has been angled to smooth the transition between the stem
and the arches.
[0054] FIGS. 37A and 37B show an embodiment of a fastener for
locking a proximal anchor.
[0055] FIGS. 38A, 38B, and 38C show another embodiment of a
fastener for locking a proximal anchor.
[0056] FIGS. 39A and 39B show another embodiment of a fastener for
locking a proximal anchor.
[0057] FIGS. 40A and 40B show another embodiment of a fastener for
locking a proximal anchor.
[0058] FIGS. 41A and 41B show another embodiment of a fastener for
locking a proximal anchor.
[0059] FIGS. 42A and 42B show another embodiment of a fastener for
locking a proximal anchor.
[0060] FIGS. 43A and 43B show another embodiment of a fastener for
locking a proximal anchor.
[0061] FIGS. 44A and 44B show another embodiment of a fastener for
locking a proximal anchor.
[0062] FIG. 45 shows an exemplary looped proximal anchor in place
in the gastrointestinal tract.
[0063] FIGS. 46A and 46B show an exemplary asymmetric looped
proximal anchor.
[0064] FIGS. 47A, 47B, 47C and 47D show another exemplary
asymmetric looped proximal anchor.
[0065] FIGS. 48A, 48B, 48C, 48D and 48E show an exemplary "FIG. 8"
looped proximal anchor.
[0066] FIGS. 49A, 49B and 49C show an exemplary proximal anchor
having a break therein and fastener configured to close the
break.
[0067] FIGS. 50A and 50B show an exemplary "FIG. 8" looped proximal
anchor having a fastener to help hold the shape.
[0068] FIG. 51 shows the stem portion of an exemplary proximal
anchor.
[0069] FIGS. 52A, 52B and 52C show an exemplary single wire for use
in forming a proximal anchor, such as the proximal anchor of FIG.
35.
[0070] FIGS. 53A, 53B and 53C show an exemplary sleeve and welding
configuration for a stem of a proximal anchor.
[0071] FIG. 54 shows a gastrointestinal device having an exemplary
secondary bulb anchor.
[0072] FIG. 55 shows a gastrointestinal device having another
exemplary secondary bulb anchor.
[0073] FIGS. 56A-56B show an exemplary shape-locked proximal
anchor.
[0074] FIGS. 57A-D show an exemplary pusher for use in delivering a
collapsible anchor.
[0075] FIGS. 58A-E show another exemplary pusher for use in
delivering a collapsible anchor.
DETAILED DESCRIPTION
Embodiments of the Device In Situ
[0076] FIG. 1 provides a view of the human gastrointestinal tract,
including the stomach 4 and duodenum of the small intestine 10.
Important features are the esophagus 2, stomach 4, antrum 7,
pylorus 8, pyloric valve 11, duodenum 10, jejunum 12 and ampulla of
Vater (or hepatopancreatic ampulla) 13, which is formed by the
union of the pancreatic duct and the common bile duct.
Functionally, the esophagus 2 begins at the nose or mouth at its
superior end and ends at the stomach 4 at its inferior end. The
stomach 4 encloses a chamber which is characterized, in part, by
the esophageal-gastric juncture 6 (an opening for the esophagus 2)
and the antrum-pyloric juncture 5 (a passageway between the antrum
7 through the pylorus 8 to the duodenum 10 of the small intestine).
The pylorus 8 controls the discharge of contents of the stomach 4
through a sphincter muscle, the pyloric valve 11, which allows the
pylorus 8 to open wide enough to pass sufficiently-digested stomach
contents (i.e., objects of about one cubic centimeter or less).
These gastric contents, after passing into the duodenum 10,
continue into the jejunum 12 and on into the ileum (not shown). The
duodenum 10, jejunum 12 and ileum make up what is known as the
small intestine. However these individual portions of the
alimentary canal are sometimes individually referred to as the
small intestine. In the context of this invention the small
intestine can refer to all or part of the duodenum, jejunum and/or
ileum. The ampulla of Vater 13, which provides bile and pancreatic
fluids that aid in digestion, is shown as a small protrusion on the
medial wall of the duodenum 10.
[0077] Embodiments of the inventive device include various forms
that provide stability in a residence site in the gastrointestinal
tract, particularly the duodenum. Some embodiments of the device,
which may be synonymously referred to as an intestinal insert, are
stabilized in the intestine by way of an anchoring member that
resides in the stomach and is too large to be swept through the
pylorus. In other embodiments, stabilizing features in the
intestine may include expanded portions of the device in the
duodenal bulb, which is larger than the more distal portion of the
duodenum, and which thereby effectively prevents distal movement
(as in FIGS. 89-90, for example).
[0078] Some embodiments of the device and associated methods of
using the device are directed toward reducing the rate of food
transit through the intestine by physical mechanisms of intervening
in the rate of food transit. In other aspects, embodiments of the
invention act by eliciting satiety signals by way of physiological
mechanisms, or, alternatively, by directly providing satiety
signals through bioactive materials or agents, or by neuronal
stimulation, thereby reducing food intake behaviorally. Some
embodiments of the device are directed toward medical purposes
broader than satiety and digestive physiology alone, although the
satiety and food consumption functionalities of embodiments of the
device and method will be described herein in greater detail. As an
example of non-obesity or satiety-inducing medical use, some
embodiments of the devise may be used as an eluting source for
bioactive agents, and as such any medically appropriate drug could
be delivered by such a device. In some aspects, embodiments of the
device may contribute to slowing food transit and/or reducing food
intake by the satiety signals generated by the intestine in direct
response to the mere physical presence of the device. Such signals
could, for example, be mediated by stretch-responsive neurons or
mechanoreceptors in the intestinal wall. In other embodiments,
satiety signals could be mediated by hormones that are responsive
to physical presence of material in the intestine, or which are
secondarily responsive to mechano-receptors. In other embodiments,
the slowing of food or the increased residency time, and the
consequent change in the chemical environment of the intestine, may
elicit responses from chemoreceptors residing in the intestine to
signal either neurally or hormonally in such a way that has a net
effect of signaling satiety.
[0079] In still other embodiments of the invention, the device may
convey bioactive material or agents that are released over time
within the intestine, the bioactive agents conveying a net signal
of satiety. In some embodiments, the bioactive agents with a net
satiety signaling effect are passively released from sites such as
coatings, depots, or reservoirs within the device. Bioactive
materials or agents have been described in detail above, but
briefly and in broad aspect may include any of hormones, drugs, or
cells. In some embodiments, bioactive agents may be held in osmotic
pumps and released by osmotic drive. Release mechanisms such as
osmotic pumps provide a level of control and predictability to
bioactive agent release, but the mechanism remains relatively
passive and without means of intervention. Other embodiments of the
invention, however, may include more active mechanisms for
bioactive agents release or delivery, as could be provided by
electrically driven pumps, or by piezoelectric elements that allow
or promote the release stored bioactive agents in response to
applied current. Such devices may include power storage elements,
or may be provided power by external sources by wired or wireless
approaches.
[0080] In still other embodiments of the invention, the device may
include electrodes or conductive elements that provide electrical
stimulation to nerves in the intestine, such resulting neural
activity contributing to a net effect of signaling satiety to the
brain. In some embodiments, satiety-related neuronal activity may
further be mediated by endocrine mechanisms. As in embodiments of
the invention with powered mechanisms for bioactive agent release,
embodiments with electrical capability may include power storage
devices, or be enabled to receive energy conveyed from external
sources.
[0081] In other aspects of the invention, embodiments of the
inserted device, with or without an anchor, may provide a platform
for bioactive agent delivery, neural stimulus delivery, or
radiation therapy delivery, for medical purposes more broad than
inducing satiety, or intervening in food transit. For the delivery
of some bioactive agents, there may be considerable advantage
associated with local delivery of an agent to an intestinal site.
Such advantages may include localization of dosing, lack of
exposure to stomach acid as occurs in oral delivery or diminished
exposure to the metabolic machinery of the liver and kidney that
i.v. drug delivery, or any form of systemic delivery faces.
Further, embodiments of the device may accommodate multiple drugs;
in some embodiments the release of such multiple drugs may be
independently controlled.
Digestive System Context of Invention
[0082] The description now addresses the digestive system, the
digestive process, and aspects of the endocrinology and
neurophysiology of satiety as they relate to embodiments of the
invention. The adult duodenum is about 20-25 cm long and is the
shortest, widest, and most predictably placed part of the small
intestine. The duodenum forms an elongated C-shaped configuration
that lies between the level of the first and third lumbar vertebrae
in the supine position. Susan Standring (ed.), Gray's Anatomy,
39.sup.th Ed., 1163-64 (2005), provides a standard reference.
Returning to FIG. 1 for reference and further detail of aspects of
the digestive system, the first part of the duodenum, often
referred to as the duodenal bulb 10a, is about 5 cm long and starts
as a continuation of the duodenal end of the pylorus 8. This first
part of the duodenum passes superiorly, posteriorly and laterally
for 5 cm before curving sharply inferiorly into the superior
duodenal flexure 465, which marks the end of the first part of the
duodenum. The second part of the duodenum, often called the
vertical duodenum 10b, is about 8-10 cm long. It starts at the
superior duodenal flexure 465 and runs inferiorly in a gentle curve
towards the third lumbar vertebral body. Here, it turns sharply
medially into the inferior duodenal flexure 475 which marks its
junction with the third part of the duodenum. The third part of the
duodenum, often called the horizontal duodenum 10c, starts at the
inferior duodenal flexure and is about 10 cm long. It runs from the
right side of the lower border of the third lumbar vertebra, angled
slightly superiorly, across to the left and ends in continuity with
the fourth part of the duodenum in front of the abdominal aorta.
The fourth part of the duodenum is about 2.5 cm in length; it
starts just to the left of the aorta and runs superiorly and
laterally to the level of the upper border of the second lumbar
vertebra. It then turns antero-inferiorly at the duodenojejunal
flexure and is continuous with the jejunum. Some embodiments of the
present invention take advantage of this predictable configuration
of the small intestine to provide duodenal/small intestinal
implants that do not require anchoring within the pylorus or
stomach, as described more fully below.
[0083] The digestive process starts when consumed foods are mixed
with saliva and enzymes in the mouth. Once food is swallowed,
digestion continues in the esophagus and in the stomach, where the
food is combined with acids and additional enzymes to liquefy it.
The food resides in the stomach for a time and then passes into the
duodenum of the small intestine to be intermixed with bile and
pancreatic juice. Mixture of the consumed food with bile and
pancreatic juice makes the nutrients contained therein available
for absorption by the villi and microvilli of the small intestine
and by other absorptive organs of the body.
[0084] Robert C. Ritter, author of "Gastrointestinal mechanisms of
satiation for food", published by Physiology & Behavior 81
(2004) 249-273, summarizes our understanding of the various means
the gastrointestinal tract uses to control appetite. He states that
the role of the stomach in satiation is to sense the volume of
ingesta arriving from a meal and to produce a variety of signaling
substances that may be involved in satiation. It is, however, the
small intestine specifically that receives these signals. Further,
it is the intestine that responds to the energy density of ingesta,
limiting further gastric emptying and signally satiety when
adequate calories have passed. Through analysis of the location of
afferent nerves (p.255), Ritter shows that vagal nerve afferents
are most concentrated in the duodenum and least concentrated more
distally in the ileum. This early concentration of afferents will
moderate appetite early in the eating process. The timeliness of
the response to nutrient intake has been further demonstrated by
others in a variety of mammals including monkeys, rats and humans.
It is clear that the reduction in food intake begins within minutes
of the start of intake and that this reduction is not therefore a
response to postabsorptive or systematic metabolic effects. These
passages of Ritter are specifically incorporated herein by
reference as relates to the positioning of the devices described
herein or for the placement and size of flow reduction elements of
embodiments of the present invention.
[0085] The presence of partially digested food within the stomach
and small intestine initiates a cascade of biological signals that
create satiety signals principally emanating from the proximal
small intestine that contribute to the cessation of food intake.
One such satiety signal is initiated by the release of
cholecystokinin (CCK). Cells of the small intestine release CCK in
response to the presence of digested foods, and in particular, in
response to dietary fat, fatty acids, small peptides, and amino
acids. Elevated levels of CCK reduce meal size and duration and may
do so through a number of different mechanisms. For example, CCK
may act on CCK-A receptors in the liver and within the central
nervous system to induce satiety signals. CCK stimulates vagal
afferent fibers in both the liver and the pylorus that project to
the nucleus tractus solitarius, an area of the brain that
communicates with the hypothalamus to centrally regulate food
intake and feeding behavior. CCK also stimulates the release of
enzymes from the pancreas and gall bladder and inhibits gastric
emptying. Because CCK is a potent inhibitor of gastric emptying,
some of its effects on limiting food intake may be mediated by the
retention of food in the stomach.
[0086] Cells of the small intestine (particularly L cells) also
release glucagon-like peptide 1 (GLP-1) and oxyntomodulin (OXM) in
response to nutrient signals of digestion. Elevated levels of GLP-1
and OXM are associated with satiety signals and the cessation of
food intake. These hormones may signal satiety by activating
receptors on afferent vagal nerves in the liver and/or the GI tract
and/or by inhibiting gastric emptying.
[0087] Pancreatic peptide (PP) is released in proportion to the
number of calories ingested, and in response to gastric distension.
Elevated levels of PP have been shown to reduce food intake and
body weight. PP may exert some of its anorectic effects via vagal
afferent pathways to the brainstem, as well as through more local
effects, such as by suppression of gastric ghrelin production.
[0088] Peptide YY.sub.3-36 (PYY.sub.3-36) is another biological
signal whose peripheral release may be correlated with reduced food
intake and/or the cessation of eating. Specifically, low levels of
PYY.sub.3-36 have been correlated with obesity while its
administration decreases caloric intake and subjective hunger
scores. Intravenous administration of PYY.sub.3-36 may reduce food
intake through its effects of suppressing ghrelin expression,
delaying gastric emptying, delaying various secretion from the
pancreas and stomach and increasing the absorption of fluids and
electrolytes from the ileum after a meal.
[0089] Insulin and leptin are two additional biological signals
that regulate satiety and eating behavior. Through parasympathetic
innervation, beta cells of the endocrine pancreas release insulin
in response to circulating nutrients such as glucose and amino
acids, and in response to the presence of GLP-1 and gastric
inhibitory peptide (GIP). Insulin stimulates leptin production from
adipose tissue via increased glucose metabolism. Increased insulin
levels in the brain leads to a reduction in food intake. Elevated
leptin levels also decrease food intake and induce weight loss.
Insulin and leptin have also been implicated in the regulation of
energy expenditure since their administration induces greater
weight loss than can be explained by reduction in food intake
alone. Both insulin and leptin act within the central nervous
system to inhibit food intake and to increase energy expenditure,
most likely by activating the sympathetic nervous system. Insulin's
effects to decrease food intake also involve interactions with
several hypothalamic neuropeptides that are also involved in the
regulation of feeding behavior such as, by way of example, NPY and
melanocortin ligands.
[0090] Other hormones or biological signals that are involved in
the suppression or inhibition of food intake include, by way of
example, GIP (secreted from intestinal endocrine K cells after
glucose administration or ingestion of high carbohydrate meals;
enterostatin (produced in response to dietary fat; amylin
(co-secreted with insulin from pancreatic beta cells); glucagon,
gastrin-releasing peptide (GRP), somatostatin, neurotensin,
bombesin, calcitonin, calcitonin gene-related peptide, neuromedin U
(NMU), and ketones.
[0091] In relation to embodiments of the present invention, when
the passage of partially digested food or chyme is partially
impeded within the duodenum of the small intestine and the flow
rate through this area is reduced (or to express the same
phenomenon in another way, as residency time is increased), the
emptying of the stomach and the duodenum will occur more slowly.
This slowing, by itself, may create extended feelings of satiety
and thus lead to a decrease in food intake (due to the longer
retention time of food in the stomach). The slowing of the passage
of food also provides more time for the partially digested food to
interact with chemoreceptors, stretch receptors, and
mechanoreceptors along the GI tract so that stimulation of satiety
signals may be increased and/or prolonged, which may, in turn, lead
to a reduction in food intake during an eating period and/or longer
periods between food intake.
[0092] In addition to keeping partially-digested food within the
small intestine for an extended period of time, the methods and
devices of the present invention may also enhance and/or prolong
the release of satiety signals by releasing signals into the small
intestine themselves. For example, in some embodiments, the methods
and devices of the present invention may release nutrient products
of digestion to stimulate chemoreceptors to cause the release of
hormones and/or other molecular signals that contribute to the
creation of satiety signals. In another embodiment, the methods and
devices of the present invention may exert a small amount of
pressure on the walls of the GI tract to stimulate stretch
(mechanoreceptors) to generate and send satiety signals to the
brain. In another embodiment, the methods and devices of the
present invention may release signals, such as, by way of example,
nutrient by-products of digestion of food, to stimulate
chemoreceptors as described above and may exert a small amount of
pressure on the walls of the small intestine as described above to
contribute to the generation of satiety signals.
Device with Flow Reduction Elements
[0093] FIG. 2 depicts several exemplary non-limiting mechanisms
through which satiety signals may be generated. As shown FIG. 2, a
by-product of digestion, such as a fatty acid or other protein,
stimulates an L-cell of the small intestine to release CCK locally
and into the circulation. CCK released locally may stimulate vagal
afferent nerve fibers in the area to generate satiety signals to
the central nervous system (CNS). CCK that enters the circulation
may travel to the liver to stimulate vagal afferent nerve fibers in
the liver to generate satiety signals to the CNS. CCK in the
circulation may travel to the gall bladder and pancreas to
upregulate the digestion-related activities of these organs. CCK in
the circulation also may travel to the CNS itself to contribute to
the creation of a satiety signal. Once satiety signals are received
and integrated within the CNS, the CNS may trigger physiological
effects that serve to contribute to a feeling of fullness and/or
the cessation, slowing or reduction of food intake.
[0094] Turning now to embodiments of the invention, FIG. 3 shows an
exemplary small intestinal insert 20 made in accordance with the
present invention that may contribute to the creation of satiety
signals. The insert 20 is positioned in the stomach 4 and small
intestine 10. The insert 20 has a proximal portion 30 and a distal
portion 40, and a central tube 50 that extends from the proximal
portion 30 to the distal portion 40. One or more flow reduction
elements 200 that are sized to fit within the small intestine 10
may be attached to the central tube 50. While not required, the
portion of the central tube 50 near the ampulla of Vater 13
generally will not include a flow reduction element 200 so that the
introduction of bile and pancreatic fluid into the small intestine
is not impeded.
[0095] In some embodiments, the central tube or spine 50 has an
anchoring member 100 near its proximal end 52, with the anchoring
member 100 securing the proximal end 52 of the central tube 50 in
the stomach. The anchoring member 100 is sized so that it will not
pass through the pylorus 8. In this way, embodiments of the present
invention including an anchoring member anchor the flow reduction
elements 200 within the small intestine. In some embodiments, the
anchoring member may be established by one or more inflatable
balloons 102 that when inflated are larger than the pylorus 8. The
inflatable balloons 102 may be deflated for delivery into the
stomach and then inflated inside the stomach. The inflatable
balloons 102 may also be deflated for later removal using
endoscopic techniques.
[0096] As will be described in further detail below, embodiments of
flow reduction elements 200 may assume many configurations, and may
vary further with regard to physical features such as composition,
nature of the surface, and porosity of the bulk material. Some
further exemplary embodiments of flow reduction elements 200 are
depicted in FIGS. 16-25. In some embodiments, as depicted in FIGS.
16, the central tube or member, also referred to as an elongated
member, may, itself, be configured into a form that reduces chyme
flow in the duodenum. A functional property that embodiments of
flow reduction elements have in common is that they slow the
transit of digesting food without blocking it, and within
clinically appropriate guidelines. The process of slowing the
transit rate may also have effects on the composition of the
digesting food material, such as varying its biochemical profile
with regard to the nutritional compounds being metabolized.
Chemical receptors and nerves of the duodenum are sensitive to the
biochemical profile of metabolites within the chyme, and
participate in the coordination of physiology of digestion and
satiety and hunger, accordingly. As such, by altering the flow rate
and hence, the biochemical profile of chyme, embodiments of the
inventive small intestinal insert contribute to the generation of
signals associated with satiety. Flow reduction elements may
further effect the composition of the digesting food material by
the mixing action the flow reduction elements may provide.
[0097] FIG. 4 shows an embodiment of the invention with a central
tube 50 that includes an outer wall 54 and an inner wall 56 that
define an interior space 58. The interior space 58 forms an inner
lumen 59 that may be continuous from the proximal end 52 of the
central tube 50 to just short of the distal end 53 of the central
tube 50. The distal end 53 of the central tube 50 is sealed at a
point 55 so that fluid introduced into the central tube 50 does not
leak out distally into the small intestine. In some embodiments a
valve 90 may be located substantially at the proximal end of the
inner lumen 59. The valve 90 may be a self-sealing valve that has a
septum 92 that may be accessed by a needle or blunt tip tube for
introduction of fluid into the inner lumen 59. The valve 90 also
may be accessed so that the fluid inside the inner lumen 59 of the
central tube 50 may be aspirated for removal. It is to be
understood that the valve type is not limited to a septum type
valve only, and that other types of mechanical valves may also be
used in place of the septum valve described. Particular embodiments
of the present invention are adapted to accept fluids in this
manner so that the devices of the present invention may be
implanted in a deflated configuration and later expanded into an
inflated configuration.
[0098] As shown in FIG. 4 and as mentioned above, one or more flow
reduction elements 200 may be attached to the central tube 50. In
some embodiments the diameter of each flow reduction element 200
may be concentric with the axis of the central tube 50. In the
embodiment depicted in FIG. 4, each flow reduction element 200 has
an outer wall 210, an inner wall 212, and an inner space 214. At or
near its proximally-oriented surface 220 and also at or near its
distally-oriented surface 222, each flow reduction element 200 may
be attached to the central tube 50 with the inner space 214 of the
flow reduction element 200 in fluid communication with the lumen 59
of the central tube 50, such that the inner space 214 surrounds the
outer wall 54 of the central tube 50. Each flow reduction element
200 may be attached to the central tube 50 by, for example,
adhesives, heat bonding, mechanical restraint or other suitable
methods.
[0099] As also depicted in FIG. 4, the central tube 50 may be
formed with plural inlet/exit ports 216 that are located inside
respective flow reduction elements 200. More specifically, each
port 216 is formed completely through the central tube wall 51 to
establish a pathway for fluid communication between the inner lumen
59 of the central tube 50 and the inner space 214 of the respective
flow reduction elements 200. Consequently, the inner lumen 59 of
the central tube 50 may be used to introduce fluid into the inner
spaces 214 of the flow reduction elements 200 and to inflate the
flow reduction elements 200 from a collapsed configuration, in
which insertion and removal of the flow reduction elements 200 is
facilitated, to an inflated configuration shown in FIG. 4, in which
resistance to food passage is increased to induce satiety. Thus, as
suggested earlier, the flow reduction element or elements 200 in
this embodiment act as balloons that may be deflated and collapsed
around the central tube 50 for introduction into the small
intestine and then inflated to the desired diameter once in
position.
[0100] Embodiments of the flow reduction elements may assume other
forms, such as coils, ribs, fans, baffles, either
peripherally-mounted or centrally-mounted, as well as sleeves, mesh
cages or baskets. Embodiments such as these are described further,
below, in the section entitled "Further exemplary embodiments of
the invention", which also includes description of embodiments with
biodegradable components, active biomaterial release mechanisms,
and nerve stimulation features, and as depicted in FIGS. 15-31.
[0101] In some embodiments, individual flow reduction elements 200
of the present invention may be elastic balloons or inelastic
balloons. When an elastic balloon material is used to establish a
flow reduction element 200, the flow reduction element 200 inflates
to a diameter that is dependent on the volume of fluid introduced
into the inner space of the flow reduction element. This embodiment
permits adjustment of the balloon size as determined by the
physician. If the balloon is too small, for instance, additional
fluid could be introduced to enlarge the balloon diameter.
Alternatively, if the balloon is too large, additional fluid could
be removed to shrink the balloon diameter. It is understood that an
alternate embodiment consisting of an inelastic balloon that
inflates to a diameter that is independent of a volume of fluid
introduced into its inner space is also included within the present
invention. The diameter of this type of balloon is fixed when
manufactured and does not permit in situ adjustment of the balloon
size. However, this type of balloon prevents possible over
inflation and rupture if too much fluid is introduced into the
balloon.
[0102] The flow reduction elements 200 shown in FIG. 4 have the
shape of a round sphere. However, other shapes are contemplated and
any shape that effectively functions to inhibit the passage of
partially digested food in the small intestine is acceptable in
accordance with the present invention. It is understood that the
ability of the small intestinal insert to remain within the small
intestine may be affected by the shape, orientation and tautness of
the flow reduction elements 200. For example alternate shapes such
as ovoid, elliptical, elongated ellipse and even irregular
non-geometrical shapes could be used in accordance with the present
invention.
[0103] FIG. 5 illustrates an alternative embodiment of the present
invention in which one or more flow reduction elements 300 are
eccentrically attached to a central tube 350. In this embodiment
the axis or diameter of the flow reduction element or elements 300
is not concentric with the axis of the central tube. The outer wall
302 of the flow reduction element is attached to the side of an
outer wall 354 of the central tube 350. An inner space 314 of each
flow reduction element 300 is eccentric relative to the axis of the
central tube 350 and is in fluid communication with an inner lumen
359 of the central tube 350 through a respective opening 316. As
was the case with the embodiment shown in FIG. 4, in the embodiment
shown in FIG. 5 the inner lumen 359 may be used to introduce and
remove fluid into the inner space 314 of the flow reduction element
300 to move the flow reduction element 300 between inflated and
deflated configurations.
[0104] In some embodiments of the present invention, the flow
reduction elements 300 may be inflated with a fluid, including a
liquid and/or a gas. In some embodiments, the gas may be, for
example, air, nitrogen or carbon dioxide. In another embodiment a
liquid may be, for example, water or water mixed with other
solutions. Any appropriate inflation medium may be modified to
deliver bioactive materials or other solutions that may diffuse
from the insert of the present invention into the small intestine
to trigger biological signals of satiety. When bioactive materials
are delivered through an inflation medium, the design of or the
materials selected for all or a portion of the spine or central
tube and/or flow reduction elements should be permeable to the
bioactive materials. Porosity may be adjusted to control the
diffusion rate of the bioactive materials.
[0105] In one alternative aspect, one or more reservoirs may be
provided to store and/or control the release of one or more
bioactive materials. In an alternative configuration of FIG. 7, one
or more of the inflatable balloons 102 contain a bioactive material
for delivery via the lumen 59 and ports to one or more elements on
the spine or via the spine itself. The balloons may be filled
before or after a device has been placed in a body or refilled
while the device remains in the body. Filling may be performed
using a valve, a port, a septum or a self-sealing mechanism
provided for that purpose and accessible to a health care provider
using endoscopic techniques. In still further aspects, the
bioactive material within the balloons 102 may be used in
conjunction with a fluid delivery system as described elsewhere in
this application whereby the balloons 102 are the reservoir for the
fluid being delivered based on the desired therapeutic outcome or
therapy being performed
[0106] When inflating the flow reduction elements of the present
invention, it may be important for the physician to monitor the
flow reduction element 300 location in the small intestine and the
diameter of the flow reduction element relative to the diameter of
the small intestine. For this purpose, the flow reduction element
may be inflated with a radio opaque fluid that is visible on X-ray.
When the flow reduction element contains radio opaque fluid, a
physician may non-invasively visualize the size and placement of
the flow reduction element(s) from outside the patient's body. This
knowledge enables the physician to adjust the size and/or placement
of the flow reduction element(s). Likewise radio opaque marker
bands 218 as shown in FIG. 5 may be placed around the central tube
to facilitate visualization of the central tube's location in the
small intestine. The radio opaque marker bands 218 may be placed at
predetermined intervals so that the distance inside the small
intestine may be used as depth markers and may be measured from
outside of the body.
[0107] The central tube and flow reduction elements of the present
invention may be flexible. In some embodiments, they may be
constructed of a polymeric material that may be easily formed or
extruded and delivered with the aid of an endoscope by known
techniques. A central tube 50 that is soft and flexible will
contour to the anatomy of the gastrointestinal tract and provide
less irritation of the stomach and intestinal lining.
[0108] FIG. 6 shows an alternative embodiment of the invention with
flow reduction elements that are generally self-expanding, and do
not necessarily include a central lumen. These embodiments include
a central shaft 450 around which flow reduction elements are
concentrically attached 400 and/or are eccentrically attached 410.
The elements 400 and 410 may be attached to the central shaft 450
by, for example, heat fusing, adhesives or other suitable methods
as known in the art. These flow reduction elements 400 may be made
from material that may be folded or collapsed to a first volume
suitable for insertion with the aid of an endoscope and then may
self-expand to a second volume suitable for restricting the flow of
partially digested food according to the present invention. These
flow reduction elements may be made from materials, or materials
may be configured so as to take the form of such as, by way of
example, a sponge, a foam, a hydrogel, or springs that may be
compacted into a small volume and then self-expand to a
pre-determined shape and volume when unrestricted. Gel- or
sponge-based embodiments may include open cell or closed cell
forms. In addition to having features that allow such gel- or
sponge-based embodiments to be collapsible and expandable for
deployment, such embodiments typically have a high surface area
which is beneficial in embodiments that may include bioactive
agents, and may further be conducive for purposes of
biodegradability. Another foam-related embodiment is described
below in the section entitled "Further embodiments of the
invention", and depicted in FIG. 21. Because the flow reduction
elements self-expand, the need for an inflation system is
eliminated and this embodiment represents a simple mechanical
design. These flow reduction elements may also be impregnated with
bioactive materials or other signals that may trigger biological
signals of satiety.
[0109] The central shaft 450 of an embodiment such as that depicted
in FIG. 6 may be solid and without an inner lumen or inner space.
In another embodiment the central shaft 450 may include a
passageway for consumed food so that the food may pass through the
small intestine without being fully absorbed.
Deployment of Inserts and Flow Reduction Elements
[0110] The description now turns to considerations related to
deployment of the inventive insert, some embodiments of which
include flow reduction elements. Flow reduction elements are
referenced in a generic sense with the label 200, but some
exemplary embodiments make use of different label numbers, for
their particular features. FIG. 9 illustrates an embodiment of the
present invention where flow reduction elements may be created
through the expansion of portions of an expandable sleeve; this
embodiment will be used in the context of describing an example of
how to deploy a device with flow reduction elements. In the
embodiment depicted in FIG. 9, a central tube 50 is attached to an
expandable sleeve 508 at the expandable sleeve's distal end 510
near the distal portion of a duodenal/small intestinal insert of
the present invention. In a delivery configuration of the depicted
embodiment, the opposite proximal end of the central tube 50 is
attached to a detachable extension tube 520 that may lock onto a
proximal portion of the central tube 50 when the flow reduction
elements 530 are expanded (post-delivery). One non-limiting method
of detachable attachment is the use of one or more screws 504,
whereby the extension tube 520 screws into the central tube 50. The
central tube 50 may be pre-formed to have a configuration that
conforms to the anatomy of the duodenum 10 shown in FIG. 1. A
central tube 50 so described would force the expandable sleeve 508
to assume the configuration of the central tube 50. The central
tube 50 may be constructed, merely by way of example, of wire,
spring, superelastic or shape memory alloys, hollow steel tubing or
plastic polymers. In some embodiments a stiffening rod or guide
wire 110 may also be inserted through the lumen of central tube
50.
[0111] The expandable sleeve 508 herein described is designed to
expand at predefined segments to allow the formation of flow
reduction elements 530. In some embodiments, the non-expanded
segments 532 of expandable sleeve 508 may be coated with a polymer
to prevent their expansion. In another embodiment, the flow
reduction elements 530 may be covered with a flexible polymer to
prevent partially digested food from entering the flow reduction
elements 530. In another embodiment, a stiffening rod or guide wire
110 may be inserted through the lumen of central tube 50 to
straighten the central tube 50 when the device is delivered into
the duodenum.
[0112] The expandable sleeve 508 may, merely by way of example be
configured as any one or more of a knit, a weave, a mesh or a braid
that may be formed, merely by way of example from any one or more
of a metal, a wire, a ribbon, a plastic polymer or a biodegradable
material.
[0113] FIG. 10 illustrates the expandable sleeve 508 consisting of
flow reduction elements 530 in a collapsed configuration for
insertion into the small intestine. In this configuration a force A
is applied to the expandable sleeve 508 to collapse the flow
reduction elements 530. The collapsed form may be restrained by a
constraining mechanism such as, merely by way of example, a sheath
or a tightly wound string, or by applying sustained traction on the
proximal end of the expandable sleeve 508. FIG. 10 also shows
portions of the central tube that will remain unexpanded 532, a
detachable extension tube 520 and a guidewire 110.
[0114] The expansion of the flow reduction elements 530 in the
embodiments depicted in FIGS. 9 and 10 may occur passively or
actively. One example of passive expansion may be the removal of a
constraining mechanism to allow the flow reduction elements 530 to
expand to an original expanded state. Another non-limiting
mechanism can be to release traction on the proximal end of an
expandable sleeve 508 to allow the flow reduction elements 530 to
expand to an original expanded state.
[0115] The flow reduction elements 530 of the embodiments depicted
in FIGS. 10 and 11 can expand in a distal to proximal fashion, a
proximal to distal fashion or in a central fashion depending on
their relative position in relation to, in some embodiments, motion
of the expandable sleeve 508 and the central tube 50 to one
another. For example, if the proximal end of the flow reduction
element lumen is held in the duodenal bulb and the central tube 50
is pulled back, the distal end of the flow reduction element lumen
may expand first. Expansion in this direction may be advantageous
because the position of the proximal end of the flow reduction
element lumen remains in the duodenal bulb.
[0116] FIG. 11 illustrates some embodiments of the present
invention that may lock the proximal end of the expandable sleeve
508 to the central tube 50 at a position to keep the flow reduction
elements in a desired expanded configuration. Traction on the
extension tube 520 retracts central tube 50 until wedge 52 engages
the proximal end of the expandable sleeve 508. The central tube 50
may have multiple ratchet-like wedges that may lock the expandable
sleeve 508 at different degrees of expansion. The extension tube
may be unscrewed from the central tube 50 after deployment of the
device and expansion of the expandable sleeve 508.
Use of the Device
[0117] FIG. 12 is a schematic flow diagram of various embodiments
of a method by which embodiments of the device engage the
physiology of the host subject, and intervene in ways to generate a
sense of satiety that ultimately reduces food intake. Embodiments
of the inventive device intervene in the physiology of digestion
and satiation by two broad approaches, each of which mimic or
exploit the natural mechanisms of satiety. Embodiments may engage
the physiology of the host subject by (1) their mere physical
presence having effects, and/or (2) they may intervene more
directly or actively by the direct provision of bioactive agents or
direct neural stimulation. FIG. 12 and this associated description
are provided as a simplified theoretical framework for
understanding the invention; it is not intended to be complete in
all detail; various interactions, dotted lines, and blurring of
distinctions are omitted for sake of simplicity.
[0118] First, the mere physical presence of a device has two main
effects, it has distensional effects and, if it has distinct flow
reduction elements, it impedes the flow of chyme. Each of these two
broad effects is dependent on the dimensions of the device and its
flow reduction system, if the latter is present. First, then, the
presence of the device distends the duodenum, and such distension
may be neurally-sensed or detected, as for example, by
stretch-sensitive neurons in the duodenum. Accordingly, any
physical dimension, aspect, or feature, such as, by way of example,
any of length, width, total volume, overall conformation or
topography, density, weight, or surface properties may affect
distension, or may be neurally detected in some way. Secondly, with
regard to physically impeding the flow of chyme, this impeding
process may alter the biochemical profile of digesting chyme, and
chemoreceptors in the duodenum sense that profile as being more
fully digested. It may also be that there is neural recognition
more specifically of longer chyme residency time, as information
separate from the altered biochemical profile per se; an effect
such as that also then may be related to neural detection of
distension. Neuronal pathways are indeed stimulated by distension,
and neuroelectric signals and/or neuropeptides and
neurotransmitters may be released for local or more distant sites
of action. Joining neural feedback are chemical signals, both from
the metabolite profile per se, and by the secretion of hormones
such as CCK. Neural and chemical responses emanate to the central
nervous system and other organs which, in sum, indicate that enough
has been eaten, and satiation is achieved. In further response, the
central nervous system supports a cessation of eating and digestive
processes slow.
[0119] Second, with further reference to FIG. 12, embodiments of
the device may intervene in a more active manner, beyond that which
is provoked by mere physical presence. Embodiments of the device
may assertively provide (1) bioactive agents and/or (2) provide
electrical stimulation of nerves which then engage the physiology
of satiety and digestion in the much the same manner, or through
the same physiological pathways described above. In sum, a variety
of effects of the presence of the device in the duodenum result in
biochemical effects or signals (such as hormonal responses, and/or
biochemical profile of metabolites both within the intestine and in
the blood stream) and neural activity involving electrical signals,
all of which converge physiologically to result in "satiety", with
its complement of sensed satiety, sensed or perceived appetite,
psychological correlates, and behavioral and habitual responses. As
such, the action of the device or the presence of the device could
be part of a method of providing therapy. The therapy may include
providing a bioactive agent from the device to a portion of the
gastrointestinal site. Moreover, this step of providing may produce
a sensation of satiety in the patient.
[0120] Embodiments of the invention, a small intestinal insert,
typically include an elongated member including at least one angled
portion and at least one flow reduction element, for slowing the
passage of chyme (or, stated in other terms, increasing the
residency time of chyme) in the duodenum, although some embodiments
of the device do not necessarily include a flow reduction element,
and in some embodiments, the central or elongated member itself may
be configured to reduce flow. These embodiments typically do have
one or two angled portions that correspond to angled target
portions of the duodenum. The configuration of the angled portions
of the insert, including the flow reduction elements, is such that
the device resides stably in the duodenum for a period of time.
Embodiments of the insert may include adaptations that contribute
to the generation of one or more physiological signals of satiety.
Embodiments of the insert may include other features, such as the
inclusion of biodegradable portions, a neurological stimulator, and
one or more releasable reservoirs of bioactive materials that can
be actively released by a bioactive material release mechanism.
[0121] Residency time of embodiments of the insert within the
targeted angled site within the duodenum will vary according to the
configuration of the embodiment and according to the particulars of
the biodegradable materials that comprise portions of the device.
Degradation of the device by biological processes is typically what
causes release or unseating, or disengagement of the device from
the target site, and elimination of the device through the
intestinal tract. It may be understood therefore, that the device
may be configured initially to sit or be seated in the targeted
angled portion of the small intestine, and then, following a period
of residency and through the effects of biodegradation, then
configured to be unseated from the target site, and eliminated from
the body by way of defecation. Biodegradability is feature of some
polymers, and may be included in polymeric portions of any
embodiment described herein.
[0122] Embodiments of the device elicit physiological signals of
satiety typically through hormonal or neurological pathways. In
some embodiments, the pathways are stimulated by the physical
presence of the device, including a portion of or the sum total of
a central member and flow reduction elements, whose collective or
individual dimensions, either length, width, or total volume, or
surface properties, are such that neuronal elements of the
intestine, such as mechanoreceptors or stretch receptors, sense the
presence of material which is interpreted as the presence of
partially digested food, and therefore stimulate neuronal messages
to the central nervous system that are interpreted as food
satiation. In some embodiments, the central member, elongated body
or spine may primarily provide the trigger for signaling. In some
other embodiments, one or more flow reduction elements may
primarily provide the trigger for signaling. In still other
embodiments, a combination of the flow reduction element or
elements and the elongated body provide the trigger for
signaling.
[0123] In other embodiments, the satiety signal may be hormonal.
Flow reduction elements slow the passage of chyme being processed
in the duodenum, the biochemical profile of the food breakdown
products is altered, and chemoreceptors in the duodenum respond to
the altered biochemical profile in a manner that conveys satiety to
the central nervous system and other portions of the digestive
system.
[0124] In still other embodiments, the device includes reservoirs
of bioactive materials that may be released, either by passive or
active mechanisms. In the embodiments, the satiety signals are
provided directly by the device, not by the endocrine pathways of
the insert's host. Embodiments of the device may include material
reservoirs of any type, including, for example, drug coatings that
elute passively, or in concert with degradation of a host coating
material, and some embodiments include reservoirs that are coupled
with pumps. Such pumps may be mechanical, harnessing for example,
biological energy conveyed by peristalsis, or electrical energy, or
mechanical energy. Some embodiments may include osmotic pumps,
which do not require input of electrical energy, but instead tap
into the stored energy of osmotic gradients. Embodiments that are
dependent on electrical energy for release by a pump typically
include an energy storage device, such as a battery or a capacitor.
Some of the powered embodiments include, as part of a larger
system, a remote stimulator that can control the action of the
pump. In some embodiments, the device may provide direct neural
stimulation, through electrodes that stimulate local nerves in the
duodenum, which convey a sensation of satiety to the central
nervous system. As with pumps, devices that include neural
stimulation features, may also include energy storage devices and
external on/off or variable power control devices that communicate
either by direct wired connection or wirelessly, as for example
through radiofrequency signals.
[0125] FIG. 13 provides a perspective view of a portion of the
human gastrointestinal tract that focuses on the duodenum of the
small intestine 10, starting at the antrum-pyloric juncture 5, and
extending to the entrance of the jejunum 12. Shown are the ampulla
of Vater 13, the site of the entrance of the hepatopancreatic duct
15, which is Ruined by the union of the pancreatic duct (from the
pancreas 9) and the common bile duct from the liver. The pylorus 8
controls the discharge of contents of the stomach through a
sphincter muscle, the pyloric valve 11, which allows the pylorus 8
to open wide enough to pass sufficiently-digested stomach contents.
These gastric contents, after passing into the duodenum 10,
continue into the jejunum 12 and on into the ileum. The duodenum
10, jejunum 12 and ileum make up what is known as the small
intestine; however the individual portions of the alimentary canal
are also commonly referred to as the small intestine. In the
context of this invention the small intestine can refer to all or
part of the duodenum, jejunum and/or ileum. FIG. 14 provides a
flattened planar view of the duodenum 10, including the rugae 19,
or inner-folding lining portion of the duodenum that form the
periphery of the inner space within which embodiments of the insert
device are positioned. Also depicted are the pylorus 8, the pyloric
valve 11, the duodenal bulb 10A, the vertical duodenum 10B, and the
horizontal duodenum 10C, the ampulla of Vater 13, and the initial
portion of the jejunum 12. This figure provides a visual background
for many of the figures that follow, each of which depicts an
embodiment of the inventive inserted device seated within the
targeted site of the duodenum.
Conformationally-Stabilized Devices in a Residence Site: General
Considerations
[0126] Embodiments of the invention include devices or intestinal
inserts with an elongated member with a proximal end and a distal
end and an angled or curved portion between the proximal end and
the distal end. The curved portion typically corresponds to a
curved aspect of a residence site in a lumen of the body, for
example, a portion of the gastrointestinal tract, and more
particularly, the duodenum. The device is stabilized against distal
or proximal movement relative to the residence site by a
conformation that corresponds to the residence site, and more
particularly, such conformation does not correspond to a site
immediately distal and/or proximal to the residence site. Depending
on the particulars of device design and location of a residence
site, the device conformation may stabilize the device against
proximal device movement, distal device movement, rotational device
movement or a combination of any of these movements. Typically in
luminal sites within the gastrointestinal tract there is a greater
accumulation of forces that tend to move a device situated therein
in a distal direction than in a proximal direction, as the general
flow of contents, and the direction of peristalsis are both
distally-directed. Accordingly, it is of particular importance that
the device be stabilized against a distal-ward drift. Additionally,
devices described herein are also suited to resisting proximal
directed forces such as regurgitation. Accordingly, some
embodiments of devices described herein are configured to resist
gastrointestinal forces that may dislodge the device from a
residence site whether the forces are proximally directed or
distally directed.
[0127] Some embodiments of conformationally-stabilized devices, as
described herein, do not rely on a hard or specific attachment or
tethering anchor to stabilize at a target residence site, nor do
they rely on an anchoring mechanism that resists downward drift by
being blocked at a site of radial dimension limitation, such as the
pylorus. Instead, embodiments of the device stabilize at a
residence site by virtue of the conformation of the device in part
or as a whole fitting into the residence site. Moreover, the device
has sufficient structural integrity that it resists being moved
relative to the residence site because an immediately distal and/or
proximal location does not conformationally accommodate the device.
Other embodiments include a proximal anchor which, in conjunction
with conformation of the device, ensures that the device will stay
in place in the duodenum.
[0128] The conformation of a device that provides its stability in
a residence site refers to the physical totality of the device,
including the dimensions in units of measure such as length, width,
and volume, as well as shape, which relates to the distribution of
the dimensions in space. While not desiring to be bound by theory,
it is believed that a device self-stabilizes at a residence site
because that position within the residence site represents the
state of least free energy in a system that includes the device and
the residence site. In other aspects, ends proximal and distal to
the corresponding curved portion are in proximity to one another
for further stability.
[0129] Aspects of the device that are adapted to provide
conformational stabilization at a target site in a lumen of the
body include physical dimensions of length and width, as well as
angles or curvature assumed by the lumen. Conformationally
stabilized (or conformationally-stabilizable devices) may vary with
respect to the degree to which their physical aspects of size and
shape correspond to the size and shape of the intraluminal
residence site to which they are targeted; their characteristic
feature is that it is their conformation that stabilizes them
against movement from the target site, once situated therein. More
particularly, it is typical that such stabilization involves at
least one curved or angled portion of the device that is
accommodated by a corresponding at least one curved angled portion
of the residence site, and the angled portion of the device
characteristically provides a curvilinear retaining force within
that site.
[0130] Some conformationally stabilizable embodiments may further
stabilize in a residence site by providing radially outward force
that meets the surrounding wall of the lumen. Conformationally
stabilizing devices further may vary with regard to their stiffness
or compliance in response to forces exerted upon them by the
luminal residence site. A device with a high degree of stiffness
bends or changes its own shape relatively little in response to
forces exerted by the residence site, while a highly compliant
device offers little resistance and complies with forces exerted on
it by bending or changing shape. A conformationally stabilized
device thus must have a sufficient degree of stiffness and overall
structural integrity in order for its conformation to maintain its
stability.
[0131] Some embodiments of a conformationally stabilizing device
have a high degree of size and angular correspondence to their
target site, in which case the residence site substantially retains
its native configuration when occupied by the device. In some of
these embodiments with a high degree of correspondence to the
target site, the angles and the placement of angles along the
length of a device substantially match the shape and linear
dimensions of the residence site. In other embodiments, the device,
in spite of having a conformation that as a whole stabilizes it at
a residence site, the device, or more specifically, the preferred
or unconstrained conformation of the device may nevertheless vary
in terms of size and shape with respect to the target site. In some
embodiments, a device with a preferred configuration that varies
with respect to the residence site does not substantially change
the shape of the residence site, as the device may be more
compliant than the residence site. In some embodiments of devices
that vary in conformation from that of the residence site, the
device, if provided with sufficient stiffness and conformational
integrity, may impart a change of shape to the luminal residence
site. Typically, the configuration of devices that changes the
shape of residence site is a feature that contributes to the
stability of the device in that target site.
[0132] Some embodiments of the conformationally-stabilizing device
are configured such that the conformation of the structure as a
whole, including substantially the totality of physical features,
is substantially directed toward providing conformational
stability. With other embodiments, however, some aspects of the
conformation of various physical features may not be directed
specifically toward providing conformational stability, but rather
may be directed toward another functional or therapeutic end, such
as reducing the flow of chyme (as detailed in U.S. patent
applications Ser. No. 11/300,283 and 11/807,107), or toward other
therapeutic purposes or modalities, as described further herein
below. In other embodiments, physical features may not be designed
singularly to support conformational stability, but, rather such
features may be designed such that they serve one or more
functional purposes. A physical feature may, for example,
contribute both to providing conformational stability and toward
another functional or therapeutic purpose. In any of these
aforementioned embodiments that include physical features that are
not specifically-focused or singularly-focused on contributing to
the stability of the device within the residence site, these
embodiments nevertheless have a sufficient total level or amount of
conformational features that are directed toward supporting
conformational stability that the device is capable of stabilizing
in a residence site by virtue of such totality of conformation,
particularly in gastrointestinal luminal sites that include one or
more curvilinear or angled aspects.
[0133] Some embodiments are targeted to the duodenum and described
in detail, but other embodiments are targeted to residence sites
elsewhere in the gastrointestinal tract. Further, as mentioned
above, some devices are configured to align with a high degree of
correspondence with their designated residence site, while other
vary in correspondence, and by such variance may alter the shape of
the residence site. Further, some devices, though stabilized
substantially by the conformation of the device which precludes
movement that displaces it from the residence site, may further
derive site-stabilizing benefit from a balance of materials-based
and construction-based features such as structural integrity,
elasticity, stiffness, and ability to counter lumen-generated
radially-inward force with a radially-outward counterforce.
[0134] Conformation refers to the physical totality of the device,
including the dimensions in units of measure such as length, width,
and volume, as well as shape, which relates to the distribution of
the dimensions in space. While the claims to this invention are not
bound by theory, to understand the invention it can theorized that
a device self-stabilizes at a duodenal residence site because its
residence there represents the state of least free energy in a
system that includes the device within the gastrointestinal
tract.
[0135] Some embodiments of the duodenal device are configured to
reside within gastrointestinal tract residence sites completely
within the duodenum. The duodenum is anatomically situated distal
to the pylorus and stomach and proximal to the jejunum, as
illustrated in FIG. 13. Some other embodiments, however, may
include portions that extend proximally in a minimal manner, into
the pylorus, and some may extend further proximally into the antrum
of the stomach. Some embodiments may extend further distally, past
the site of the ligament of Treitz, and into the jejunum. However,
even these embodiments that include portions extending proximally
or distally from the duodenum still rely on conformational
stabilization within the duodenum to preclude dislodgment from the
residence site and consequent movement of the device as a whole. As
a result, such embodiments do not rely, for example, on being
constrained from distal or downstream movement by the radial
constraint of the pylorus.
[0136] The duodenal residence site of embodiments of the device
includes at least one angled portion, and the device, accordingly
has at least one angled portion that corresponds to that angled
portion within the residence site. Other embodiments of the device
may include two, three, four, or more angled portions between the
proximal and distal end of the device, these angles corresponding
to angles in a residence site. The duodenal residence site can also
be understood as a continuous curvilinear form, and accordingly,
some embodiments of the device are configured as a curvilinear
form, without particular angled regions.
Example of Duodenal Devices with a Proximal End Terminating in the
Gastric Antrum and a Distal End Terminating Near the Duodenojejunal
Junction
[0137] Turning now to illustrative examples of embodiments of
devices and various features, as described above, which have a
proximal end terminating in the gastric antrum, a distal end
terminating in the region of the duodenojejunal junction, and a
central curved portion configured to conform to a duodenal lumen
between its proximal and distal ends. The device described with
respect to FIG. 15 (or any of the devices described herein) can
further include a proximal anchor configured to anchor the device
in the duodenum.
[0138] FIG. 15 shows an embodiment of a device 20 including flow
reducing elements 200 along a spine 50 having a proximal portion
20P that terminates in the gastric antrum; and the distal portion
20D that terminates near the duodenojejunal junction. The spine 50
of central curved portion forms a loop, with the proximal 20P and
distal 20D ends coming to be in near apposition with each, and in
some cases crossing each other near their termini. The device in
FIG. 15 is depicted into its preferred configuration, i.e., the
configuration it assumes at rest. As described above, the devise
can be forced into a linear configuration for inclusion in the
working channel of an endoscope in preparation for deployment. Once
implanted in the residence site in the gastrointestinal tract, the
overall configuration of the device approaches the preferred
configuration, but is generally slightly constrained. For example,
the overall curvature may be made slightly more obtuse, by the
counterforce exerted by the gastrointestinal tract on the
device.
[0139] Also depicted in FIG. 15 is a flow reducing element 200
comprising braided filaments that form a plurality of
radially-expanded segments; the braided element is arranged in a
coaxial manner around the Nitinol body of the device. The figure
depicts five segments, but the number may vary, as described above.
The braided flow reduction element 200 is fixed to the device at
its distal end, but freely slideable on its proximal end within
limits. A proximal sliding movement limit is represented simply by
the length the braided element. The slack for sliding comes from
the trade-off between radial expansion of the expandable segments
and the absolute linear length of the braid as the expandable
segments are drawn in. The distal limit on the slideable range of
the braided element is provided by slide stopper feature 730. This
feature is fused to the Nitinol body and has a radial profile over
which the braided element 200, itself, can freely slide, but
sufficiently high that it blocks distal movement of an end ring 740
at the proximal terminus of the braided element 200. The purpose of
this stop feature 730 is to prevent an extreme distal movement or
collapse of the braided element as whole, which could defeat its
function (i.e., to reduce chyme flow, not to block it).
[0140] Also depicted in FIG. 15 is a pushable shoulder 720 on the
proximal portion of the device, the purpose of which is to provide
a surface against which a pushing element can eject the device (in
its linearized configuration) from the working channel of an
endoscope.
[0141] FIG. 17 shows the device 20 depicted in FIG. 15 in a
gastrointestinal residence site, with the proximal portion 20P of
the device terminating in the gastric antrum, and the distal
portion 20D terminating near the duodenojejunal junction or the
duodenojejunal flexure 14. It can be seen that the portion of
device 20 that transits through the pylorus 8 is a bare portion of
the device, without the flow reduction element 20. The dimension of
the spine 50 alone is sufficiently small that the pylorus does not
feel its presence, an advantageous feature as described above.
[0142] FIG. 18 shows an alternative embodiment of a device 20
similar to that shown in FIG. 15, with a large single flow
reduction element. Other features of the device are substantially
the same as those described above with reference to FIG. 15. This
embodiment may have therapeutic advantages for some particular
applications of the device.
[0143] In some embodiments of the inventive device, one or more
flow reduction elements may be positioned on the device so that
when implanted the flow reduction element is within a specific
portion of the anatomy or within a position where the flow element
with produce a desired result. Possible locations for one or more
flow reduction elements include: (a) within the duodenal bulb; (b)
within the proximal duodenum; (c) distal to the duodenal bulb; (d)
distal to the duodenal bulb and within the vertical duodenum; (e)
within 5 cm of the pylorus; (f) one or more positions within the
duodenum selected to increase the probability of rector activation
in the duodenum (for specific location examples see Ritter article
mentioned above and specifically incorporated by reference).
[0144] In one aspect of the present invention, the proximal and
distal ends of the device are in close proximity once the device is
implanted into a residence site. In one aspect, the proximal end is
within 1 cm to 7 cm the distal end. In another aspect, the proximal
end is within 1 cm to 3 cm of the distal end. In still another
aspect, the proximal end is within 1 cm to 5 cm of the distal end.
In still another aspect, the proximal and distal ends be separated
by 1 cm or less or may even urge the adjacent tissue into contact.
However, in these embodiments, the contact will urge tissue
movement and may produce contact between the stomach and the
duodenum but without providing sufficient pressure against the
involved tissue to form a pressure necrosis or cause erosion or
damage to the involved tissue.
Embodiments Having an Extended Proximal or Distal End
[0145] FIGS. 19-23 illustrate embodiments of the inventions
described herein in relation to the esophagus 2, the stomach 4, the
duodenum 10, and the jejunum 12. The duodenum 10 includes the
duodenal bulb 10A, the vertical or descending duodenum 10B, the
horizontal duodenum 10C, and ascending duodenum 10D as described
herein in. Other anatomic features shown in the various figures
include the esophagus 2, the esophageal sphincter 6, the stomach 4,
jejunum 12 and duodenojejunal flexure 14 region of the duodenum 10.
These embodiments also illustrate the various portions of the
stomach 4 including the greater curvature 4A, lesser curvature 4B
and fundus 4C.
[0146] In one aspect, the embodiments of FIGS. 19-21 provide
variations to the proximal end of a device. The proximal device end
is extended such that the terminal end is within the stomach
proximal to the pylorus. Still further, the proximal end, proximal
terminal end or a feature of the proximal end of the device is
positioned beyond (i.e., proximal to) the active region of the
stomach. In this embodiment, the active region of the stomach
refers to that portion of the distal stomach near or about the
pyloric valve 11, pylorus 8 and antrum 7. In the examples that
follow, the length, curvature or shape of the spine 50 is adjusted
to place the proximal portion of the device into stomach regions
beyond the active regions. Other details of the device spine,
functional features and distal end may vary according to the other
alternative aspects described herein. It is appreciated that the
lengthening aspects that follow may be applied to other embodiments
in order to vary the length of the device or to alter the relative
positions of the proximal and distal ends of an implanted device
from those positions shown and described above.
[0147] FIG. 19 provides a section view distal esophagus, stomach,
duodenum and proximal jujunem with an implanted device extending
from a proximal portion within the stomach and a distal portion
beyond the horizontal duodenum at or near the near the
duodenojejunal junction. In this embodiment, there is a spine 50
and ends 61 similar in the form to that of FIG. 15. The spine 50 of
the embodiment of FIG. 19 differs in that the its length produces a
residence site placement of the device with a proximal portion 20P
that terminates beyond the gastric antrum 7 and the distal portion
20D that terminates near the duodenojejunal junction. The length
may vary from that illustrated. For example, the length of the
spine 50 may be altered so as to place all or a portion of the
proximal portion 20P or the end feature 61 into contact with the
stomach wall opposite or adjacent to the pyloric region. The length
may be adjust to have the proximal portion 20P just in contact or
in varying degrees of firm apposition with the inner wall of the
stomach. As with the prior embodiments, the spine 50 of central
curved portion forms a loop at the terminal ends of the proximal
20P and distal 20D ends. Alternatively, the device may have end
portions or other atraumatic terminal ends. The device depicted in
FIG. 19 is within the anatomy in its preferred configuration, i.e.,
the configuration it assumes at rest and after deployment. As
described above, the device can be forced into a linear
configuration for inclusion in the working channel of an endoscope
in preparation for deployment. Once implanted in the residence site
in the gastrointestinal tract, the overall configuration of the
device approaches the preferred configuration, but is generally
slightly constrained. For example, the overall curvature may be
made slightly more obtuse, by the counterforce exerted by the
gastrointestinal tract on the device.
[0148] FIG. 20 provides a section view distal esophagus, stomach,
duodenum and proximal jujunem with an implanted device extending
from a proximal portion beyond the active portion of the stomach
and a distal portion beyond the horizontal duodenum at or near the
near the duodenojejunal junction. The spine 50 of the embodiment of
FIG. 20 differs from the embodiment of FIG. 19 in that the its
length produces a residence site placement of the device with a
proximal portion 20P that terminates beyond the gastric antrum 7
but along the lesser curvature 4C. Additionally, the curvature of
the spine 50 alters at an inflection point 55A. The inflection
point 55A represents the change in the overall curvature of the
spine 50 producing a proximal region 55C and a distal region 55B.
The curvature of the spine 50 may also vary in the region proximal
to the inflection point (region 55C) or distal to the inflection
point (region 55B). In the illustrated embodiment, the curvature of
the inflection point 55A along with the curvature of the proximal
region 55B cooperate that portion of the spine where the proximal
portion or end shifts in order to place all or a portion of the
proximal end along the lesser curvature. The inflection point 55A
may be viewed as a transitional radius of curvature between the
proximal portion shaped and configured to conform to the lesser
curvature and the central spine portion shaped and configured
generally to the curvature of the lower stomach and duodenum.
[0149] The length of the device may vary from that illustrated in
FIG. 20. For example, the length of the spine 50 may be altered so
as to place all or a portion of the proximal portion 20P or the end
feature 61 into contact with the stomach wall along the lesser
curvature 4 near the pylorus, near the lower esophageal sphincter 6
or at any place along the lesser curvature 4. The characteristics
of the proximal portion may be adjusted to have the proximal
portion 20P just in contact or in varying degrees of firm
apposition with the stomach wall of the lesser curvature.
Characteristics of the proximal portion such to modifications
include, for example, one or more of the angle of the spine at the
inflection point 50A, the cross section shape of the spine or the
size or shape of the terminal end.
[0150] As with the prior embodiments, the spine 50 of central
curved portion in FIG. 20 forms a loop 61 at the terminal ends of
the proximal 20P and distal 20D portions. Alternatively, the device
may have end portions or other atraumatic terminal ends. The device
depicted in FIG. 20 is within the anatomy in its preferred
configuration, i.e., the configuration it assumes at rest and after
deployment. As described above, the device can be forced into a
linear configuration for inclusion in the working channel of an
endoscope in preparation for deployment. Once implanted in the
residence site in the gastrointestinal tract, the overall
configuration of the device approaches the preferred configuration,
but is generally slightly constrained. For example, the overall
curvature may be made slightly more obtuse, by the counterforce
exerted by the gastrointestinal tract on the device.
[0151] FIG. 21 provides a section view distal esophagus, stomach,
duodenum and proximal jujunem with an implanted device extending
from a proximal portion beyond the active portion of the stomach
and a distal portion beyond the horizontal duodenum at or near the
near the duodenojejunal junction. The embodiment of FIG. 21
replaces vertical proximal anchor having a proximal end curved so
as to extend up into the upper stomach. Moreover, this type of
anchor may include one or more undulations in the central member to
aid in maintaining position and resisting peristaltic action. The
spine 50 of the embodiment of FIG. 21 differs from the embodiments
of FIGS. 19 and 20 in that the length produces a residence site
placement of the device with a proximal portion 20P that terminates
beyond the gastric antrum 7 but towards the upper stomach. In the
illustrative embodiment, the terminal end 61 is within the fundus
4C. As with the embodiment of FIG. 20, the curvature of the spine
50 alters at an inflection point 55A. The inflection point 55A
represents the change in the overall curvature of the spine 50
producing a proximal region 55C and a distal region 55B. The
curvature of the spine 50 may also vary in the region proximal to
the inflection point (region 55C) or distal to the inflection point
(region 55B). In the illustrated embodiment, the curvature of the
inflection point 55A along with the curvature of the proximal and
distal regions 55B, 55C cooperate so that the proximal portion or
end shifts in order to place all or a portion of the proximal end
along or within the upper stomach or fundus 4C. The inflection
point 55A may be viewed as a transitional radius of curvature
between the proximal portion shaped and configured to conform to
the lesser curvature and the central spine portion shaped and
configured generally to the curvature of the duodenum. Peristalsis
(indicated generally by arrows) produces a downward motion on the
proximal portion 20P thereby pressing the inflection point 55A into
the stomach wall rather than towards the pyloric region or towards
the pylorus.
[0152] The length of the device may vary from that illustrated in
FIG. 21. For example, the length of the spine 50 may be altered so
as to place all or a portion of the inflection point 55A near the
pylorus or antrum while the proximal portion 20P or the end feature
61 is placed into contact with the stomach wall along the fundus 4C
or upper portion of the stomach or greater curvature 4A or at any
place along the greater curvature 4A. The characteristics of the
proximal portion may be adjusted to have the proximal portion 20P
just in contact or in varying degrees of firm apposition with the
stomach wall. Characteristics of the proximal portion such to
modifications include, for example, one or more of the angle of the
spine at the inflection point 55A, the curvature and/or length of
the proximal region 55C, the curvature and/or length of the distal
region 55B, the cross section shape of the spine or the size or
shape of the terminal end.
[0153] As with the prior embodiments, the spine 50 of central
curved portion in FIG. 21 forms a loop 61 at the terminal ends of
the proximal 20P and distal 20D portions. Alternatively, the device
may have end portions or other atraumatic terminal ends. The device
depicted in FIG. 21 is within the anatomy in its preferred
configuration, i.e., the configuration it assumes at rest and after
deployment. As described above, the device can be forced into a
linear configuration for inclusion in the working channel of an
endoscope in preparation for deployment. Once implanted in the
residence site in the gastrointestinal tract, the overall
configuration of the device approaches the preferred configuration,
but is generally slightly constrained. For example, the overall
curvature may be made slightly more obtuse, by the counterforce
exerted by the gastrointestinal tract on the device.
[0154] FIG. 22 provides a section view distal esophagus, stomach,
duodenum and proximal jujunem having a device with a distal portion
in residence at the site of the duodenojejunal flexure 14. The
device is curvilinear with an angle that conforms at least
partially to the flexure 14 and a distal end that extends beyond
the flexure 14 to an atraumatic distal end 61 disposed within the
jejunum 12. FIG. 22 illustrates a device having a proximal end
within the stomach and beyond the pylorus as in FIG. 76. The
illustrated embodiment has proximal and distal terminal ends each
having a coiled feature 61 as described above. The distal portion
of the device includes an inflection point 57A representing the
change in curvature of the spine 50 from the proximal region 57B to
the distal region 57C. In the illustrated embodiment, the
inflection point 57A and regions 57B, 57B form a radius of
curvature conforming to or approximating the curvature of the
gastrointestinal tract in the transition from the ascending
duodenum 10D to the jejunum 12 along the duodenojejunal flexure 14.
A plurality of flow reduction elements 200 are illustrated along
the spine 50. The flow reduction elements are shown along the
length of the device from portion within the duodenal bulb 10A to
the distal portion 20D within the jejunum 12. The flow reduction
elements 200 may vary from the illustrated embodiment. The flow
reduction elements 200 may take the shape, size, construction,
orientation or any attribute of the flow reduction elements
described herein.
[0155] FIG. 23 provides a section view distal esophagus, stomach,
duodenum and proximal jujunem having a device with an inflection
point mimicking the duodenojejunal flexure 14. The distal portion
of the device may conform in length or shape to the anatomy of the
duodenum at the D-J flexure 14. In another aspect, the device is
curvilinear with an angle that conforms at least partially to the
flexure 14 and a distal end that extends beyond the flexure 14 to
an atraumatic distal end 61 disposed within the jejunum 12. FIG. 23
illustrates a device having a proximal end within the stomach and
beyond the pylorus as in FIG. 76. The illustrated embodiment has
proximal and distal terminal ends each having a coiled feature 61
as described above. The distal portion of the device includes an
inflection point 57A representing the change in curvature of the
spine 50 from the proximal region 57B to the distal region 57C. In
the illustrated embodiment, the inflection point 57A and regions
57B, 57B form a radius of curvature conforming to or approximating
the curvature of the gastrointestinal tract in the transition from
the ascending duodenum 10D to the jejunum 12 along the
duodenojejunal flexure 14. The inflection point 57A in FIG. 23
represents a tighter radius than in FIG. 22. The inflection point
57A in FIG. 23 may vary from the illustrated embodiment to more
closely conform to the angle of the duodenojejunal flexure 14, be
smaller (i.e., tighter radius) or larger (i.e., larger radius) than
that of the natural duodenojejunal flexure 14.
Devices with Anchoring Member in Stomach
[0156] Anchoring members that reside in the stomach and are too
large to be swept through the pylorus can be used with any of the
devices described herein and/or with any device having a portion
that extends distal to the pylorus.
[0157] Basic Anchor Designs
[0158] FIG. 7 depicts one such anchoring mechanism. In FIG. 7, the
central tube 50 has an anchoring member 100 near its proximal end
52. The anchoring member 100 may be established by one or more
inflatable balloons 102 positioned in the proximal end 52 of the
device. These balloons 102 may be eccentrically attached to the
central tube at point 104 near the proximal end 52 of the central
tube 50. These balloons may be formed in many shapes and are not
limited to the spherical shape shown. The central tube may be
formed with an opening 116 for each respective balloon 102 so that
a pathway for fluid communication is established between the inner
lumen 59 of the central tube 50 and the inner space of each balloon
106. The inner lumen 59 is used to introduce fluid into the inner
space of the balloon 106 and inflate the balloon 102 from a first
volume in a collapsed state to a second volume or inflated state.
When the one or more balloons 102 of the anchoring member 100 are
fully inflated, they secure the proximal end of the central tube 52
such that it cannot pass through an adjacent orifice, such as the
pylorus 8. The one or more inflatable balloons 102 have a combined
cross sectional diameter greater than the diameter of the pyloric
valve to prevent migration across the pylorus. The inflatable
balloons 102 may be inflated and deflated by adding or removing
fluid from the central tube inner lumen 59. The inflatable balloons
102 may be connected to the same central tube inner lumen 59 as the
one or more flow reduction elements attached to the central tube
and may be inflated simultaneously with the flow reduction
elements. The central tube 50 may also have more than one inner
lumen so that the inflatable balloons 102 and individual one or
more flow reduction elements may be inflated and deflated
independently as well.
[0159] FIG. 8 illustrates another embodiment of the invention,
wherein an anchoring member 100 of the present invention is
deployed in the antrum 7. In this embodiment, a central tube 50 is
attached to an inverted umbrella skeleton 160. This skeleton 160
has a ring 162 that surrounds the central tube 50 and is supported
by struts. In the depicted embodiment the ring 162 is supported by
three struts 164, 165, and 166, however more or fewer struts may be
successfully employed. In the embodiment depicted in FIG. 8, the
struts are joined together at the central tube 50 at point 167 and
attached to the ring 162 at points 170, 171 and 172. The ring 162
of this anchor configuration may be made from, by way of example,
flexible plastic material or flexible wire and has a diameter
significantly larger than the diameter of the pyloric valve. This
umbrella skeleton 160 may be collapsed around the central tube 50
for insertion into the stomach with the aid of an endoscope. As the
device is released from the endoscope, the umbrella skeleton 160
may spring out and assume a configuration similar to that shown in
FIG. 8. The struts 164, 165 and 166 may be made from, by way of
example, plastic, metal or from plastic covered metal. The edge of
the ring which is in contact with the antrum walls 163, may be
constructed to assist in securing the umbrella ring 162 to the
walls of the antrum.
[0160] FIG. 24 provides a section view of the distal esophagus,
stomach, duodenum & proximal jujunem having a device that
illustrates another embodiment of the invention, wherein an
anchoring member 5905 of the present invention is deployed in the
antrum 7. The anchoring member 5905 includes a base 5910 with an
opening 5915 and one or more lines 5920. The one or more lines 5920
are used to attach the base 5910 to the spine 50 at or near its
proximal end via attachment point 5925. In one alternative, instead
of lines 5920, a cone or funnel is used to attach a base 5910 to
the spine 50. The cone or funnel could be made of a solid sheet of
material or a mesh. The remainder of the spine 50 and distal end
may take any of the different configurations described herein. The
base 5910 has a perimeter sized so as to remain within the antrum
and/or not pass through the pylorus with an open middle portion
5915 to allow food to pass. The base 5910 may be of any open shape
such as circular, oval, oblong, rectangular and the like. In the
illustrated embodiment, the base 5910 is a ring. In an additional
aspect, the anchoring member 5905 may include a valve to further
meter the flow of food therethrough. The anchoring member 5905 may
be made of a biocompatible polymer. The anchoring member 5905 may
be completely or at least partially hollow. The hollow portions of
the anchoring member 5905 may be filled with air or a fluid. A
hollow anchoring member 5905 may be advanced to the implant site in
a stowed or uninflated configuration and then filled into a
deployed configuration once placed in the implant site.
[0161] In an alternative configuration of FIG. 24, anchoring member
5905 may be formed of a ring made of a stiff material, such as
metal, to prevent collapse from peristalsis. In another aspect, the
anchoring member 5905 could be a frame or scaffold structure that
collapses for delivery and then springs into shape upon delivery.
In one aspect, the anchoring member 5905 may be shaped like an
inverted umbrella skeleton with a ring supported by struts as shown
and described above in FIG. 8. The components of the anchor member
5905 may be made from, by way of example, flexible plastic material
or flexible wire and has a diameter significantly larger than the
diameter of the pyloric valve. The anchoring member 5905 may be
collapsed around the spine 50 for insertion into the stomach and
duodenum with the aid of an endoscope. As the device is released
from the endoscope, the anchoring member 5905 may spring out and
assume a configuration similar to that shown in FIG. 24 or achieve
such configurations after suitable inflation. The one or more lines
or struts 5920 may be made from, by way of example, plastic, metal
or from plastic covered metal. In another aspect, the edge of the
ring 5910 which is in contact with the stomach walls, may be
constructed to assist in securing the anchoring member 5905 to the
stomach walls such as thorough the use of hooks, barbs, coils or
other piercing or penetrating devices.
[0162] Expandable Proximal Anchors
[0163] FIGS. 30-34 illustrate various alternative expandable
proximal anchor embodiments. These anchor embodiments are adapted
and configured to--once deployed into the stomach--provide a large
enough structure that will prevent passage of the anchor through
the pylorus. The spine and distal anchor in each of these
embodiments is illustrated in a minimal way so as to not distract
from the additional details being provided for the proximal anchor.
As such, it is to be appreciated that any of the above described
flow reduction elements, sleeves, features, characteristics,
qualities or capabilities of the duodenal based treatment devices
described herein may be used in conjunction with the proximal
anchors described herein. Additionally or alternatively, FIGS.
30-34 may be used with any of the above described duodenal
devices.
[0164] FIGS. 30A-30B show an embodiment of one proximal anchor
mechanism. The proximal anchor mechanism can include a ball 6512.
The ball 6512 can include a plurality of struts 6514 configured to
expand. For example, the struts 6514 can extend longitudinally from
the spine and approximately parallel to one another. The struts
6514 can then be configured to expand outwards to form the ball
6512, as shown in FIG. 30A. For example, the struts 6514 can be
formed of a shape-memory alloy, such as Nitinol, so that the struts
can expand into a preformed shape after delivery. The struts 6514
can thus be thin and/or flexible to allow collapse and expansion
without requiring too much force and/or without causing damage to
the struts 6614. Further, while the ball 6512 is shown as
substantially spherical, it could also take other shapes, such as
an oblong shape.
[0165] Referring still to FIGS. 30A and 30B, the struts 6514 can be
unfinished, polished or, alternatively covered by a thin membrane,
such as a thin fabric or polymer, e.g., ePTFE, silicone, or
polyurethane. The thin membrane can be sewed or otherwise secured
onto the struts themselves or dip-coated directly onto the struts
such that a ball 6512 is formed in its expanded state. As such, it
is to be appreciated that the covering can be applied so that each
individual strut may behave as described herein or that the ball
formed by a plurality of struts has the characteristics described
herein. By covering the struts 6514 with a thin membrane, the
struts alone or together forming the ball 6512 can provide an
enclosed hollow space, providing a reservoir for gases, such as air
or CO2, a fluid, such as water or saline, hydrogels, or
bio-absorbable drug compounds that could be advantageous upon
delivery. The thin membrane can be impenetrable, disallowing escape
of gases or liquids, or penetrable, allowing materials therein to
escape over time.
[0166] In one aspect, the inflatable structure (i.e., the strut, a
ball or a combination thereof) may be filled with a selected
material to bulk up the strut and/or ball in order to enhance the
anchoring characteristics of the device. Additionally or
alternatively, the filling material and membrane may be selected to
maintain a fill amount but also to leak out the filling material
over time. This time release aspect of the membrane and filler
material permits the anchor to act as a drug delivery device by
selecting therapeutically active ingredients as the filler
material. Moreover, the particular membrane may be selected to
permit passage of the filler material at a set rate of osmosis or
permissive leaking.
[0167] In one embodiment, the thin membrane is a self-sealing
substance that seals in situ over time. In one exemplary
embodiment, the self-sealing compound is a layer of silicone. The
silicone layer may general be thinner over the strut or ball but
then a thicker area is used for insertion of a needle or other
suitable filling device that pierces the silicone membrane and
permits refilling. The thickness of the silicone layer in this area
is selected so that upon withdrawal of the filling device tip, the
silicone layer closes up to maintain a suitable pressure tight
seal. If a self-sealing substance is used, periodic injections
could be used to fill or refill the ball with a material throughout
the in situ dwell period. In another aspect, the struts or ball may
have a valve or sealing area to permit periodic refilling. Various
hollow lumens and internal ports and other filling techniques
described above in FIGS. 3, 4 and 5 may also be applied to the
struts and/or ball.
[0168] FIGS. 31A-31B show a proximal anchor, similar to the
embodiment of FIGS. 30A-30B, having a ball 6612 formed of struts
6614 that expand from a collapsed configuration (FIG. 31B) to an
expanded configuration (FIG. 31A). The struts 6614 can be combined
in such a way that the ball 6612 expands both laterally and
radially upon deployment. Similar to the embodiment of FIGS.
30A-30B, the ball 6612 can include a membrane 6616 thereon to
provide an enclosure within the ball 6612.
[0169] Looped Wire Anchors
[0170] FIGS. 25, 32-35, and 45-50 show devices having proximal
anchors formed from looped wires. The looped wires of the devices
shown in FIGS. 25, 32-35, and 45-50 can straighten for delivery
through a standard delivery tube and can be configured to resume or
be forced into the looped shape once deployed in the stomach. The
devices of FIGS. 25, 32-35, and 45-50 can further be collapsed or
straightened once deployed for removal from the stomach through a
standard tube.
[0171] FIG. 25 provides a section view of a device having a looped
proximal anchor 6061 on the proximal end that is different than the
diameter and/or radius of curvature of the coil 61 (or other
terminus) on the distal end. As shown in FIG. 25, the coil can
extend in-plane with the spine 50. The coil can have a diameter
that is larger than the diameter of the pylorus 5. The large
diameter of the coil 6061 can advantageously help prevent the coil
from being pulled into the pylorus and can thus help anchor the
device in the GI tract. As shown in FIG. 25, the coil 6061 can be
formed as a spiral that extends from the spine 50 and curves
inwards. In some embodiments, the coil can be a continuous
extension of the spine 50.
[0172] The coil 6061 may be formed by a nearly complete coil (i.e.,
less than one complete loop), a complete loop or more than one
loop--having an overlapping portion of all or part of additional
turns of a coil. In some embodiments, the diameter of the proximal
coil 6061 may be sized to cover a span determined by the interior
dimensions of the stomach. In one embodiment, the diameter of the
coil is large enough to extend across a portion of the stomach on
the lesser curvature to a portion on the greater curvature. In
still another aspect, the coil is from different radius of
curvature or from turns with different diameters.
[0173] In other embodiments, the coil 6061 may form into spiral or
helical shapes or shapes that are out of plane with other turns of
the coil or with the device. Still further embodiments have the
proximal coil oriented in a vertical orientation within the
stomach, a horizontal orientation in the stomach or in combinations
thereof.
[0174] The characteristics, qualities and dimensions including the
cross section shape of the spine of FIG. 25 may be modified in
order to adapt the spine to the particular properties desired based
on the residence site for the coil 6061.
[0175] In one embodiment, referring to FIG. 45, a looped proximal
anchor 8061 includes a coil 8062. Similar to the anchor of the
embodiment of FIG. 25, the coil 8062 can extend in-plane with the
spine 50 and can have a diameter that is larger than the diameter
of the pylorus 5, which can advantageously help prevent the anchor
8061 from being pulled into the pylorus and can thus help anchor
the device in the gastrointestinal tract. In contrast to the
embodiment of FIG. 25, however, the anchor 8061 can include a stem
8065 that extends from the spine 50 and then curves around to form
the coil 8062. The coil 8062 can extend around the stem 8065 such
that the stem 8065 runs through, i.e., substantially in the center
of, the coil 8062. Having the stem 8065 advantageously provides a
centering and stabilizing mechanism for the anchor 8061 when pulled
distally by the pylorus. That is, as the spine 50 and thus the stem
8065 are pulled proximally, the coil 8062 will press up against the
stem 8065, making it difficult for the coil 8062 to unwind and pull
through the pylorus 5. Further, in some embodiments, a locking
mechanism 8017, similar to any of the locking mechanisms described
above, can be used to hold the shape of the coil 8062.
[0176] The coil 8062 can be formed by less than a complete loop, a
complete loop, or more than one loop with an overlapping portion.
In some embodiments, the coil 8062 is oriented in a vertical
orientation within the stomach, a horizontal orientation within the
stomach, or a combination thereof. Further, the spine 50 can be
modified to include any of the properties described above, such as
a sleeve, flow reduction elements, etc.
[0177] FIGS. 32A-33 shows an embodiment of a proximal anchoring
member 6701. The anchoring member 6701 can include a stem 6703
extending axially with the spine, an arch 6705 extending radially
away from the stem 6703, and a coil 6707 extending annularly or at
least partially around the stem 6703, i.e., perpendicular to the
stem 6703. As shown in FIGS. 32A-32B, the arch 6705 can connect the
coil 6707 with the stem 6703. The stem 6703, arch 6705, and coil
6705, can be formed of a single unitary elongate body, such as a
piece of wire.
[0178] The stem 6703 can have a diameter of less than 0.0050
inches, such as between 0.025 inches to 0.050 inches, such as
between 0.035 inches to 0.043 inches. Further, as shown in FIGS.
32A-32C, in some embodiments, the stem 6703 can have a diameter
that is the same as the diameter of the spine. In some embodiments,
the spine and stem 6703 along with the intervening coil and arch
can be formed of a continuous piece of wire. In some embodiments,
the diameter of the wire used for the stem, the arch, the coil or
coils and the spine is about the same. In an alternative
embodiment, the coils and the spine have the same wire diameter
that is smaller than the wire diameter of the arch and the stem. In
still another embodiment, the wire diameter of the stem is larger
than the wire diameter of the arch as well as the coils and the
spine. In still another aspect, the diameter of the wire formed
into the coils is different in each of the coils. In addition to
the representative wire diameters for the stem above,
representative wire diameters for the other portions of the device
include for example, the arch ranging from about 0.025 inches to
about 0.035 inches; the coil or coils ranging from about 0.035 to
about 0.040 inches and the spine ranging from about 0.035 to about
0.045 inches.
[0179] As shown in FIGS. 32A-33, the arch can extend both
longitudinally and radially away from the stem 6703. This arching
form can advantageously provide additional hoop strength in helping
to center the coil when it is pushed or compressed from the side.
The transition of the arch to the coil can further provide an
"interlock" if the coil 6707 moves proximally with respect to the
stem 6703 when in situ. This interlock would engage if the arch
transition is flared outside the coil diameter or if the coil
diameter is smaller than the arch transition. Further, having an
arched configuration can provide a smooth and seamless transition
when straightening the anchor 6701 for delivery. To defeat the
interlock feature, the arch needs to be slightly squeezed together
as the coil is pulled proximally over it in a straightening manner.
Finally, the arch 6705 form a simple retraction loop should the
device need to be removed from a patient after delivery. In an
alternative embodiment, the arch 6705 can be replaced with a
connecting portion that extends substantially perpendicularly from
the stem 6703 to the coil 6707. In this embodiment instead of an
arc pathway from the stem to the perimeter coil the wire extends
from the stem in a direct path to the coils while remaining
generally in a plane containing the coils.
[0180] The coil 6707 can be formed by nearly a complete loop, a
complete loop, or more than one loop, i.e., having an overlapping
portion of all or part of additional turns of a loop. Thus, the
coil 6707 can be formed of approximately 1 loop to 4 loops, such as
1 loop to 2 loops. For example, as shown in FIGS. 32A-32B, the coil
6707 can include approximately 1.5 loops. Having more than one loop
can advantageously provide increased cumulative hoop strength of
the coil 6707 without increasing the stiffness of the wire making
up the coil 6707. Keeping a low stiffness of the wire can
advantageously help with ease of straightening of the wire when
inserting the device into the endoscope handle, decreased force
during delivery and decrease damage to the tissue (tissue damage
may occur if a wire is too stiff).
[0181] The coil 6707 can have a diameter such that, when placed in
the stomach 4 perpendicular to the pylorus 5 (see FIG. 33), it is
not able to pass through the pylorus 5. Thus, for example, the
diameter of the coil 6707 can be between 3 cm and 20 cm, such as
between 5 cm and 15 cm. The coil 6707 can end in an atraumatic end,
such as a smaller coil as shown in FIGS. 32A-32C. Additionally or
alternatively, the terminal end may have a slightly enlarged
bulbous end as shown in FIGS. 32A and 33, for example. A bulbous
end as shown may be formed by directing a high-power laser on the
end of the wire.
[0182] FIG. 32A also illustrates a shoulder or feature on one of
the coils. This feature is positioned on the wire to provide a
connection point for an insertion or device delivery. While shown
on the lower coil at about the 9 o'clock position, this location is
for purposes of example. The shoulder feature may be placed in a
wide variety of locations depending upon a number of factors such
as the insertion device used or the specific design parameters of
the anchor. The feature may be a short cylinder attached to the
wire at a suitable location.
[0183] The proximal anchor 6701 can be preshaped to take the
expanded configuration shown in FIGS. 32A-32C. For example, the
proximal anchor 6701 can be made of a shape-memory material such as
Nitinol. Accordingly, the proximal anchor 6701 can be straightened
for delivery, such as through an endoscope. The device can return
to its preformed shape as it is released from the endoscope and
then, as shown in FIG. 33, be fully released in the stomach 5. As
shown in FIG. 33, the coil 6707 can be placed substantially
perpendicular to the pylorus 8. The perpendicular placement of the
coil 6707 ensures that, even if the pylorus 8 stretches out to form
an oblong shape, it cannot stretch enough to allow passage of the
coil 6707. Further, the thin diameter of the stem 6703
advantageously ensures that the pylorus 8 is able to grab ahold of
as little of the device as possible. Finally, the sudden transition
from the thin stem 6703 to the large diameter coil 6707 can provide
a solid stop or shoulder that helps to further prevent the anchor
6701 from migrating through the pylorus 8, i.e., because the entire
diameter of the coil 6707 can work to spread out the forces from
the pylorus 8. Further, the coil 6707 of the anchor 6701 can be
configured to sit proximally away from the pylorus 8, such as
inside the antrum 5 or proximal to the antrum 5, to avoid
undesirable and constant contact with the pylorus 8, such as to
avoid irritation. In one aspect, the combination of stem length,
arch bending radius and overall diameter of the coils are such that
irritation of the pylorus may be reduced or minimized during use.
Variations in the relationship of these elements may be used to
alter the orientation of the device within the stomach as well as
in relation to the pylorus. The placement of the anchor 2701 can
also advantageously place the spine in the desired location for
effective treatment based upon the specific configuration of the
flow reduction element or devices arranged along the spine for
positioning within or along the duodenum as described herein.
[0184] FIGS. 31A-34C illustrate proximal anchor 6901 similar to the
proximal anchor 6701 of FIGS. 32A-32C. The proximal anchor 6901,
however, includes two arches 6905a, 6905b extending from the stem
6903. Each arch 6905a, 6905b includes a corresponding coil 6907a,
6907b. The resulting two coils 6907a, 6907b are substantially
aligned with one another to form a multi loop hoop structure
6917.
[0185] The arches 6905a, 6905b are configured to extend in
substantially opposite radial directions. Having the arches 6905a,
6905b extend in substantially opposite radial directions
advantageously provides a balancing force when stress is placed on
the coils from a sideways direction 1907a, 1907b. That is, if there
is only one arch, a lateral force may cause the arch to collapse
radially inward. However, if there are two arches 6905a, 6905b
extending in substantially opposite directions, then the two arches
6905a, 6905b can provide opposing inward forces on each other,
thereby helping to keep the arches 6905a, 6905b in an upright
position with the stem 6903 centered between the arches 6905a,
6905b.
[0186] The proximal anchor 6901 can include two portions 6912a,
6912b of wire extending parallel to one another into a single stem
6903. Each stem portion 6912a, 6912b can have a diameter of less
than 0.0050 inches such that the diameter of the stem 6903 is less
than 0.010 inches. The portions 6912a, 6912b can remain unattached
along a substantial portion or all of the length of the stem 6903
except a portion used for joining by welding, brazing, crimping or
other suitable process. A suitable length of weld may range from
about 2.5 to about 10.0 mm. Alternatively, a spot weld or a
plurality of spot welds may be used to join multiple wires (e.g.,
two or three wires) to form the central stem portion of the device.
Keeping the majority of the portions of the anchor 6912a, 6912b
unattached can advantageously provide flexibility for the anchor
6901 as various stresses are applied to the device during delivery
and use in situ. An attachment point 6914 can mark where the spine
transitions into the stem 6903, which can be distal of the coils
6907a, 6907b. By having the attachment point 6914 distal of the
coils 6907a, 6907b, the area of higher stress around the coils
6907a, 6907b can be avoided, thereby avoiding potential snapping at
the attachment point 6914.
[0187] As shown in FIGS. 34A-34C, the coils 6907a, 6907b of the
proximal anchor 6901 can both extend in the same direction, such as
counterclockwise. In another embodiment, the coils 6907a, 6907b
could extend in opposite directions. Each coil 6907a, 6907b can be
formed by nearly a complete loop, a complete loop, or more than one
loop, i.e., having an overlapping portion of all or part of
additional turns of a loop. Thus, each coil 6907a, 6907b can be
formed of approximately 1 loop to 4 loops, such as 1 loop to 2
loops. For example, as shown in FIGS. 32A-32B, each coil 6907a,
6907b can include approximately 1.5 loops. Further, the coils
6907a, 6907b can be configured to start and end such that a
thickness of the entire hoop structure 6917 is substantially
equivalent all the way around the diameter, e.g., there are
approximately 3 loops at each point along the diameter of the hoops
structure 6917.
[0188] In a still further alternative, there may be three separate
wires joined into a common, central stem with three arches spaces
equidistantly about 120 degrees part then into coils of suitable
number as described elsewhere. The winding of the three separate
coils may be all the same direction or alternating directions. For
example, the top and bottom coils may be wound in counter clockwise
fashion and the middle coil wound in clockwise fashion. Other
alternative winding orientations are possible. In other
embodiments, a proximal anchor can include more than three arches
and corresponding coils are possible, such as 4 or 5 arches, each
with its own corresponding coil.
[0189] The elongate body can be preshaped to take the expanded
configuration shown in FIGS. 34A-34C. For example, the elongate
body can be made of a shape-memory material such as Nitinol.
Accordingly, the proximal anchor 6901 can be configured to be
straightened for delivery, such as through an endoscope. In order
to effectively straighten the device, the two arches 6905a, 6905b
can be brought together, e.g., one of the arches 6905a, 6905b can
be pulled 180.degree. or both arches can be pulled approximately
90.degree. to meet in the middle. By aligning the arches 6905a,
6905b with one another, the coils 6907a, 6907b can be pulled around
and over the arches 6905a, 6905b, thereby unraveling the coils
6907a, 6907b and straightening the entire anchor 6901.
[0190] It is to be appreciated that there a plurality of recovery
modes for the anchors described herein. Any one or a combination of
these recovery modes or techniques can be used to collapse the
stem-arch-coil anchor structure to permit removal from the implant
location in the stomach. In one aspect, withdrawal of a component
of the device refers generally to a movement away from the pylorus.
One recovery mode is to grasp the arch and withdraw it away from
the coil. Additionally or alternatively, the withdrawal action may
be in a line generally parallel to the stem or, optionally, at a
non-zero angle relative to the stem. This movement will then
withdraw the coil and spine along with the stem. Another recovery
mode involves first grasping one of the coils and withdrawing it.
In a similar way, this action will unwind the remaining coils,
collapse the arch or arches and permit the now unwound anchor to be
withdrawn in unwound form along with the stem and spine. In still
another form of recovery, the terminal end of the coil (i.e., the
small ball tip or curved terminal end) is grasped and withdrawn
generally away from the pylorus. This action will result in the
coil being unwound and then the arch or arches following behind the
stem and the spine. The proximal anchor 6901 can thus be configured
to sit in or just proximal of the antrum similar to the proximal
anchor 1701 shown in FIG. 33. Selection of the length of stem and
arch allow for a wide variety of anchor placements. In addition,
the selection of the overall diameter of the anchor (i.e., the
diameter across the circumference formed by one or more of the
coils) may also be chosen to assist in anchoring the device while
also reducing or minimizing pyloric irritation by limiting contact
with the pylorus to the stem.
[0191] FIGS. 35A-35D show another embodiment of a proximal
anchoring member 7001. The anchoring member 7001 can include a stem
7003 extending axially from the spine, two arches 7005a,b extending
radially away from the stem 7003, coils 7007a,b extending annularly
or at least partially around and perpendicularly to the stem 7003,
and a pull loop 7077 connected through the two arches 7005a,b and
merging into the coils 7007a,b.
[0192] Each arch 7005a,b extends proximally from the stem 7003,
curves through a proximal peak, and extends distally to merge into
a respective coil 7007a,b. The arches 7005a,b can thus extend both
longitudinally and radially away from the stem 7003. This arching
form can advantageously provide hoop strength by helping to center
the coils 7007a,b when the anchor 7001 is pushed or compressed from
the side. In some embodiments, the arches 7005a,b extend further
radially then the coils 7007a,b. The transition of the arches
7005a,b to the coils 7007a,b can provide an "interlock" when the
stem 7003 moves distally in the pylorus relative to the coils
7007a,b, as the arches 7007a,b will be prevented from pulling
through the coils 7007a,b.
[0193] The arches 7005a,b can both extend counterclockwise (from
the proximal point of view) as they merge into the coils 7007a,b.
Further, the arches 7005a,b are configured to extend in
substantially opposite radial directions. Having the arches 7005a,b
extend in substantially opposite radial directions advantageously
enables the arches 7005a,b to behave as moment arms and assume
approximately half of the imparted load in a balanced manner. This
forces the load path to originate at the end of the virtual moment
arm at the coils 7007a,b and travel through the arches 7005a,b to
the central stem 7003 where they join. This equal and opposite load
path balances the imparted load. As a result, the coils 7007a,b
maintain an orthogonal orientation with respect to the stem 7003,
resulting in a large span from one coil 7007a,b to the opposite,
thereby creating a larger proximal anchor 7001. That is, the two
arches 7005a,b can support each other, thereby helping to keep the
arches 7005a,b in an upright (proximally-extending) position, the
coils 7007a,b orthogonal to the stem 7003, and the stem 7003
centered between the arches. Having a centered stem 7003
advantageously reduces the likelihood of damage to the pylorus
caused by the anchor 7001 being pushed off-center by muscular
contractions.
[0194] The pull loop 7077 can include a loop portion 7076 that
extends in between the arches 7005a,b as they meet at the stem
7003. Counterarch portions 7079a,b can extend from the loop portion
7076. A counterarch can extend substantially opposite to, or
counter to, an arch, and can have a radius of curvature that is
smaller than the radius of curvature formed by the coils and/or
formed by a circle extending perpendicular to the stem and around
the outermost portion of the arches. In this embodiment, each
counterarch portion 7079a,b can extend from the loop portion 7076
to a respective coil 7007a,b. The peak of the counterarch portions
7079a,b can extend distally until it is approximately within the
plane of the coils 7007a,b. The counterarch portions 7079a,b can
extend in substantially opposite radial directions from one
another. Further, the counterarch portions 7079a,b can have a peak
that is approximately 90 degrees away from the peak of each arch
7005a,b (using the stem as a central axis). This placement at 90
degrees provides for approximately four supports--at every 90
degrees around the circumference of the anchor 7001--to stabilize
the anchor 7001 and discourage proximal movement of the anchor
7001. The counterarch portions 7079a,b can both loop in a
counterclockwise direction to connect to the coils 7007a,b. Thus,
the counterarch portions 7079a,b can extend counterclockwise while
the arches 7005a,b extend clockwise. In other embodiments, the
arches 7005a,b can extend counterclockwise while the counterarches
7079 extend clockwise.
[0195] The arches 7005a,b can extend underneath (or distal to) the
counterarches 7079a,b as they transition to the coils 7007a,b. This
relative axial position of the arches 7005a,b and the counterarches
7079a,b provides additional interlocking and stability for the
anchor 7001. This placement also facilitates collapse of the anchor
7071 when the pull loop is pulled in a proximal direction, as
discussed further below.
[0196] In some embodiments, the stem 7003, arches 7005a,b, coils
7007a,b, spine and pull loop 7077 can be formed of a continuous
piece of wire that is joined at the stem. Alternatively, the stem
7003, arches 7005a,b, coils 7007a,b, and/or spine can each be
joined together using, for example, welding, crimping, gluing,
soldering, sleeving or a combination of these.
[0197] The wire used for the stem 7003, arches 7005a,b, coils
7007a,b and spine, and pull loop 7077 can have the same or
different diameters. The diameter of each can be between 0.01 to
0.06 inches, such as 0.016 to 0.050 inches, such as between about
0.018 to 0.044. In some embodiments, the diameters of the stem
7003, arches 7005a,b, coils 7007a,b and spine can be chosen to
"tune" the wire to hold its shape with relatively greater or less
force (by increasing or decreasing the wire's bending moment of
inertia). For instance, the wire for the stem 7003 can be of a
larger diameter than the coils 7007a,b and arches 7005a,b to resist
deflection while the wire for the coils 7007a,b can be of a smaller
diameter than the stem 7003 and arches 7005a,b to allow for flexing
of the coils 7007a,b (minimizing stomach irritation). Likewise, the
wire of the arches 7007a,b can have an even larger diameter than
the wire of the stem 7003 and coils 7007a,b to increase stiffness
and resist deformation and possible subsequent movement through the
pylorus. The pull loop 7077 can have a relatively small diameter
(see FIG. 35D), particularly near the loop portion 7076, to allow
the anchor 7071 to be pulled into an endoscope, e.g., to allow the
loop portion 7076 to collapse.
[0198] The interlock feature described above can be "unlocked" to
remove the anchor 7001. To do so, the pull loop 7077 can act as a
"handle" that can be pulled axially in a proximal direction with a
retraction tool, such as a grasper, directly into the esophagus,
into an endoscope working channel, into an overtube or into another
device configured for removal. As the pull loop 7077 is pulled in a
direction opposite the proximal anchor, anchoring member 7001
collapses radially inwards: the coils 7007a,b lift up and around
the arches 7005a,b, until the arches straighten and collapse as
well. The pull loop 7077 can be retracted into the endoscope
working channel to initiate device removal. The coils 7007a,b and
arches 7005a,b will then twist and collapse together in parallel
fashion as they enter into the distal endoscope working channel.
Collapse of the arches 7005a,b and coils 7007a,b is facilitated by
exerting an opposing tension on the stem 7003 of the anchoring
member 7001 as the pull loop 7077 is retracted into the
endoscope.
[0199] For delivery, the interlock feature can likewise be
"unlocked" by squeezing the arches 7005a,b together such that they
are side-by-side to facilitate collapse of the proximal anchor for
device collapse in the distal direction. This allows the coils
7007a,b to collapse and twist over the arches 7005a,b for entry
into the endoscope working channel. The coils 7007a,b and arches
7005a,b can then self-expand or pop back into position after
delivery.
[0200] The coils 7007a,b can take the form of a partial loop or
more than one loop, i.e., having an overlapping portion of all or
part of additional turns of a loop. Thus, each coil 7007a,b can be
formed of approximately 1/2 loop to 4 or more loops. Having more
than one loop can advantageously provide increased cumulative hoop
strength of the coils 7007a,b without needing to increasing the
diameter and therefore the stiffness of the wire making up the
coils 7007a,b. Keeping a low stiffness of the wire has several
advantages, including making it easier to straighten the wire for
insertion into the endoscope working channel, decreased force
during delivery, and decreased potential of damaging tissue (tissue
damage may occur if a wire is too stiff). The coils 7007a,b can
have a diameter such that, when placed in the stomach perpendicular
to the pylorus, the anchor 7001 is not able to pass through the
pylorus. Thus, for example, the diameter of the coils 7007a,b can
be between 3 cm and 20 cm, preferentially between 5 cm and 15
cm.
[0201] In one embodiment, the shape of the wire is symmetrically
mirrored in its path as followed up the stem 7003, through the arch
7005a,b, around the coil 7007a,b, up to the pull loop 7077, and
then back down in a symmetric and opposite fashion to the other end
of the wire at the junction with the stem 7003. By altering the
symmetry of the path as it returns to the stem 7003 from the pull
loop 7077, the wire can be made to take a more independent shape
which can be advantageous to minimize the potential for tangling of
equal and parallel features. For example, if the distal-most end of
the wire has a 1.25 in diameter coil, and the medial section of
wire has a 1.5 in diameter coil, the two coils will be less likely
to nest into one another and tangle during insertion, delivery and
removal with the pull loop. The amount of asymmetry can be low
enough as to avoid unbalancing or substantially interfering with
the performance of the anchor 7001.
[0202] The proximal anchoring member 7001 is adapted and configured
to--once delivered through an endoscope and deployed into the
stomach--expand to provide a large enough structure that will
prevent passage of the anchor through the pylorus. The spine and
distal anchor in FIGS. 35A-35D illustrated in a minimal way so as
to not distract from the additional details being provided for the
proximal anchor. As such, it is to be appreciated that any of the
above described flow reduction elements, sleeves, features,
characteristics, qualities or capabilities of the duodenal-based
treatment device described herein may be used in conjunction with
the proximal anchors described herein. Additionally or
alternatively, the anchoring member 7001 may be used with any of
the above described duodenal devices.
[0203] FIGS. 46A-46B show another embodiment of a proximal
anchoring member 8001. The anchoring member 8001 can include a stem
8003 extending axially away from the spine (not shown), two arches
8005a,b extending radially away from the stem 8003, a coil 8007
extending annularly or at least partially around and
perpendicularly to the stem 8003, a counterarch 8079, and a pull
loop 8077 connected between the two arches 8005a,b.
[0204] The proximal anchoring member 8001 is asymmetric about the
stem 8003 in that one arch 8005a extends proximally away from the
stem 8003, curves through a proximal peak, and extends distally to
merge into a single coil 8007. The coil 8007 then curves proximally
into the pull loop 8077, which extends over the center connection
point 8099 of the two arches 8005a,b. The pull loop 8077 then
merges into the counterarch 8079, which merges into the second coil
8005b, which then joins the stem 8083 at connection point 8099.
Thus, the two arches 8005a,b do not mirror one another as they
merge into the rest of the anchor 8001. Further, the coil 8007 does
not extend all the way around the circumference of the anchor 8001
(though in some cases, it can), and there is only one counterarch
8079. By having an asymmetric anchor, the various portions of the
anchor can take independent shapes during delivery and removal,
which can advantageously minimize the potential for tangling of
equal and parallel features. The asymmetric anchor also includes
less wire than, for example, a symmetric design where the coil
extends all the way around the stem, which reduces the bulk and
potential for tangling. In some cases, the asymmetric design can
also be used to preferentially augment anchoring depending on
orientation to the main curve distal to the proximal anchor.
[0205] The arches 8005a,b can thus extend both longitudinally and
radially away from the stem 8003. This arching form can
advantageously provide hoop strength to the anchor. Further, the
arches 8005a,b can extend in substantially opposite radial
directions. Having the arches 8005a,b extend in substantially
opposite radial directions advantageously enables the arches
8005a,b to behave as moment arms and assume approximately half of
the imparted load in an almost balanced manner. Likewise, having
two arms that extend in substantially opposite radial directions
can help keep the stem in the center of the pylorus, helping to
stabilize the anchor.
[0206] The counterarch 8079 can be located approximately 90 degrees
away from both arches 8005a,b. The counterarch 8079 can
advantageously transfer the load from the arches 8005a,b to the
coil 8007 through the pull loop 8077.
[0207] In some embodiments, the stem 8003, arches 8005a,b, coil
8007, spine, and pull loop 8077 can be formed of a continuous piece
of wire that is joined at the stem. Alternatively, at least some of
the stem 8003, arches 8005a,b, coil 8007, and/or spine can be
individually joined together using, for example, welding, crimping,
gluing, soldering, sleeving or a combination of these.
[0208] The pull loop 8077, which is connected one side to the
counterarch 8079 and on the other side to the coil 8077, can be
used to straighten the anchor 8001, such as for removal or
delivery. To do so, the pull loop 8077 can act as a "handle" that
can be pulled axially in a proximal direction with a retraction
tool, such as a grasper, directly into the esophagus, into an
endoscope working channel, into an overtube or into another device
configured for removal. As the pull loop 8077 is pulled in a
direction opposite the proximal anchor, anchoring member 8001
collapses radially inwards: the coil 8007 and the counterarch 7079
lift up and around the arches 8005a,b until the arches straighten
and collapse as well. The pull loop 7077 can be retracted into the
endoscope working channel to initiate device removal. The anchor
8001 will thus follow. Alternatively, the anchoring member 8001 can
include a reduced diameter portion at approximately the mid-point
of the anchor, such as at approximately point 8088. For delivery or
removal, the anchor can thus be unwound by pulling on the
reduced-diameter section to stretch and elongate the shape.
[0209] The coils 8007 can have a diameter such that, when placed in
the stomach perpendicular to the pylorus, the anchor 8001 is not
able to pass through the pylorus. Thus, for example, the diameter
of the coil 8007 can be between 3 cm and 20 cm, preferentially
between 5 cm and 15 cm. The proximal anchoring member 8001 is
adapted and configured to--once delivered through an endoscope and
deployed into the stomach--expand to provide a large enough
structure that will prevent passage of the anchor through the
pylorus. It is to be appreciated that any of the above described
flow reduction elements, sleeves, features, characteristics,
qualities or capabilities of the duodenal-based treatment device
described herein may be used in conjunction with the proximal
anchor 8001. Additionally or alternatively, the anchoring member
8001 may be used with any of the above described duodenal
devices.
[0210] FIGS. 47A-47D show another embodiment of a proximal
anchoring member 8201. The anchoring member 8201 can include a stem
8203 extending axially away from the spine, two arches 8205a,b
extending radially away from the stem 8203, and a coil 8207
extending annularly or at least partially around and
perpendicularly to the stem 8203.
[0211] The proximal anchoring member 8201 is asymmetric about the
stem 8203 in that the two arches 8205a,b extend in opposite
directions (one counterclockwise and the other clockwise) to both
merge into the same coil 8207. The coil 8207 thus extends only part
way around the circumference of the anchor 8201 (though it can
extend more than one time around the circumference of the anchor
8201). By having an asymmetric anchor, the various portions of the
anchor will be less likely to twist on themselves during delivery
and removal, which can advantageously minimize the potential for
tangling of equal and parallel features. Likewise, the simple
design (having only arches and a single short coil) can help avoid
tangling during delivery or removal. This simple design also
requires a shorter wire, thereby reducing the length of wire that
separates the two arch forms, ultimately creating a stiffer form.
In some embodiments, this asymmetric design can preferentially
augment anchorage. Further, in some embodiments, the coils of the
anchoring member 8201 (or of any anchoring member described herein
having coils) can have the coil extended at an angle greater than
90 degrees relative to axis of the stem. For example, the coil
could be angled at 120 degrees relative to the top stem (could
extend below the plane perpendicular to the stem shown in FIG.
47A). Such an increased angle could advantageously help prevent the
coil from flipping over the arches during use.
[0212] The arches 8205a,b can extend both longitudinally and
radially away from the stem 8003. This arching form can
advantageously provide hoop strength for the anchor. Further, the
arches 8205a,b can extend in substantially opposite radial
directions. Having the arches 8205a,b extend in substantially
opposite radial directions advantageously enables the arches
8205a,b to behave as moment arms and assume approximately half of
the imparted load in a balanced manner. Further, having the arches
8205a,b extend in substantially opposite directions can help keep
the stem in the center of the anchor, thereby enhancing stability
of the anchor.
[0213] In some embodiments, the stem 8203, arches 8205a,b, coil
8207, and spine (not shown) can be formed of a continuous piece of
wire that is joined at the stem. Alternatively, at least some of
the stem 8203, arches 8205a,b, coil 8207, and/or spine can be
joined together using, for example, welding, crimping, gluing,
soldering, sleeving or a combination of these.
[0214] In some embodiments, the anchor 8201 can include a
reduced-diameter section 8291 along the wire at approximately the
mid-point of the wire forming the anchor. The reduced-diameter
section can allow the anchor to bend easier at that section than in
other areas of the wire, acting as a hinge for delivery and
removal. Thus, to collapse the anchor 8201, the user can pull on
the reduced-diameter section 8291 to cause the anchor to
collapse.
[0215] The coil 8207 can have a diameter such that, when placed in
the stomach perpendicular to the pylorus, the anchor 8201 is not
able to pass through the pylorus. Thus, for example, the diameter
of the coil 8207 can be between 3 cm and 20 cm, preferentially
between 5 cm and 15 cm. The proximal anchoring member 8201 is
adapted and configured to--once delivered through an endoscope and
deployed into the stomach--expand to provide a large enough
structure that will prevent passage of the anchor through the
pylorus. It is to be appreciated that any of the above described
flow reduction elements, sleeves, features, characteristics,
qualities or capabilities of the duodenal-based treatment device
described herein may be used in conjunction with the proximal
anchor 8201. Additionally or alternatively, the anchoring member
8001 may be used with any of the above described duodenal
devices.
[0216] FIGS. 48A-48E show another embodiment of a proximal
anchoring member 8301. The anchoring member 8301 can include a stem
8303 extending axially away from the spine, two arches 8305a,b
extending radially away from the stem 8303, two counterarches
8379a,b, and a pull loop 8377.
[0217] The proximal anchor 8301 can take approximately the shape of
a FIG. 8. Each arch 8305a,b extends proximally from the stem 8303,
curves through a proximal peak, and extends distally to merge into
a respective counterarch 8379a,b. The arches 8305a,b can extend
both longitudinally and radially away from the stem 8303. This
arching form can advantageously provide hoop strength by helping to
center the anchor 8301 when the anchor 8301 is pushed or compressed
from the side. The FIG. 8 shape of the anchor 8301 can
advantageously prevent tangling during delivery and removal because
the features and free length of the wire are minimized and because
there are no overlapping coils or other portions to get
tangled.
[0218] The counterarches in FIG. 48 are shown as peaking or lying
in a plane that is substantially perpendicular (90 degree angle) to
the axis of the stem. In some embodiments, the counterarches of the
anchor 8301 (or the counterarches of any anchor described herein)
can be angled at more than a 90 degree angle relative to the top of
the stem, such as 120 degrees (i.e. could extend below the plane
perpendicular to the stem shown in FIG. 48A). Such an increased
angle could advantageously help prevent the counterarches from
flipping up and over the arches in use.
[0219] The arches 8305a,b can both extend counterclockwise (from
the proximal point of view) as they merge into the counterarches
8379a,b. Further, the arches 8305a,b are configured to extend in
substantially opposite radial directions. Having the arches 8305a,b
extend in substantially opposite radial directions advantageously
enables the arches 8305a,b to behave as moment arms and assume
approximately half of the imparted load in a balanced manner.
[0220] The pull loop 8377 can extend in between the arches 8305a,b
as they meet at the stem 8303. Further, the pull loop 8377 can
merge on both sides into counterarch portions 8379a,b, which then
curve upwards into the arches 8305a,b. The peak of the counterarch
portions 8379a,b can extend distally and in substantially opposite
radial directions from one another. Further, the counterarch
portions 8379a,b can be located approximately 90 degrees away from
each arch 8305a,b. This placement at 90 degrees provides for
approximately four supports--at every 90 degrees around the
circumference of the anchor 8301--to stabilize the anchor 8301 and
discourage proximal movement of the anchor 8301. The counterarch
portions 8379a,b can both loop in the same
clockwise/counterclockwise direction from the pullwire 8377
(viewing the anchor from the proximal end) to connect to the arches
8005a,b).
[0221] In some embodiments, the stem 8303, arches 8305a,b,
counterarches 8379a,b, spine and pull loop 7077 can be formed of a
continuous piece of wire that is joined at the stem. The stem 8303,
arches 8305a,b, counterarches 8379a,b, spine and pull loop 7077 can
be joined together using, for example, welding, crimping, gluing,
soldering, sleeving or a combination of these.
[0222] The interlock feature described above can be "unlocked" to
remove the anchor 8301. To do so, the pull loop 8377 can act as a
"handle" that can be pulled axially in a proximal direction with a
retraction tool, such as a grasper, into an endoscope working
channel. As the pull loop 8377 is pulled in a direction opposite
the proximal anchor, anchoring member 8301 collapses radially
inwards: counterarches 8379a,b lift up and around the arches
8305a,b, until the arches straighten and collapse as well. The pull
loop 8377 can be retracted directly into the esophagus, into the
endoscope working channel, into an overtube or into another device
configured for removal to initiate device removal. In some
embodiments, rather than having a separate pull loop, the FIG. 8
can include a reduced diameter portion 8529 along the portions of
the wire forming the FIG. 8 (see FIGS. 50A-50B). The
reduced-diameter portion 8529 can be at approximately the mid-point
of the anchor. For delivery or removal, the anchor can thus be
unwound by pulling on the reduced-diameter section 8520 to stretch
and elongate the shape.
[0223] The anchor 8301 can have a diameter such that, when placed
in the stomach perpendicular to the pylorus, the anchor 8301 is not
able to pass through the pylorus. The proximal anchoring member
8301 is adapted and configured to--once delivered through an
endoscope and deployed into the stomach--expand to provide a large
enough structure that will prevent passage of the anchor through
the pylorus. It is to be appreciated that any of the above
described flow reduction elements, sleeves, features,
characteristics, qualities or capabilities of the duodenal-based
treatment device described herein may be used in conjunction with
the proximal anchor 8301. Additionally or alternatively, the
anchoring member 8301 may be used with any of the above described
duodenal devices.
[0224] The anchoring members described herein, such as the
anchoring members of FIGS. 7, 8, 24-26A, 30-35, 45-50, and 56 that
reside in the stomach, that are not attached to the tissues, that
are designed so as to not be swept through the pylorus, and that
can be deployed through the working channel of an endoscope can be
used with any of the devices described herein and/or with any
device having a portion that extends distal to the pylorus and
intended to stay in place.
[0225] As an aid to clarify the relationship between and
orientation of the various anchor components (e.g., stem, coil,
arch, and counterarch) and configurations of those components, an
exemplary central axis and reference planes have been shown in some
embodiments. FIGS. 32A, 34A, 35B, 46A, 47A, and 48A have been
illustrated with exemplary references planes 5903, 5905 (shown in
dotted lines) and an exemplary central axis 5901 (also shown in
dotted lines) extending through the stem. Each respective figure
includes one plane 5903 that is parallel with the stem and includes
one or more arch or a portion thereof. Plane 5905 is perpendicular
to the stem/central axis 5901. In many embodiments, the plane 5905
includes either a coil or a distal portion of an arch or counter
arch, or portion thereof. The references planes 5903, 5905 and axis
5901 have been included to provide a reference for the various
angles of the exemplary configurations. It is to be understood that
the stem, arches, coils, and/or counterarches may not extend
exactly within these planes in some embodiments. Even if the
component does not lie completely within a reference plane, the
reference planes and axis also provide a way of interpreting the
information in the figures. For example, an arch may be described
as curving away from the stem at an angle relative to the stem or
axis 5901 as shown in FIG. 32A or pair of arches in FIG. 34A. In
another example, an arch may be described as curving away from or
towards a reference plane 5903 at an angle. While many embodiment
illustrated have one or both arches remaining generally within a
reference plane 5903, the disclosure is not so limited. Portions of
an arch or aches may be curved away from or towards the reference
plane 5903. In another example, the angle formed by a counter arch
may be described relative to the plane 5905 as shown in FIGS. 35B
and 46A. In still another example, the arch-coil transition may be
described as an angle in relation to the reference plane 5903.
Similarly, the coil--arch transition or coil to counter arch
transition may be viewed as the angle formed from the coil lying
generally within the plane 5905 and then angling out of plane 5905
towards the arch or counter arch, depending upon embodiment. While
specifically illustrated in FIGS. 32A, 34A, 35B, 46A, 47A and 48A,
it is to be appreciated that the disclosure includes these
reference planes and central axis in each of the figures
illustrating an anchor embodiment.
[0226] Locks for Looped Anchors
[0227] Any of the above anchor embodiments can further include a
fastener to help hold the shape of the anchor (rather than to just
close a break). For example, as shown in FIGS. 50A-50B, an anchor
8501 similar to the anchor 8301 of FIGS. 48A-48D can include a
latching mechanism 8517 to hold the anchor in its shape. In this
example, the latch 8517 can connect a first loop of the "FIG. 8" to
a second loop of the "FIG. 8," thereby limiting the translation and
collapse of the wire and helping to maintain the anchor shape.
[0228] As another example, referring to FIGS. 26A and 26B, a
retainer 6105 can be used to lock a portion of the coil of the
anchor 6061 (of FIG. 25) together. The retainer 6105 is positioned
to further prevent the coil 6061 from losing structure and able to
be straightened out. The retainer 6105 is placed along the coil
6061 to fasten the coil to itself. The retainer 6105 may be
installed on the coil 6061 after the device is implanted in the
gastrointestinal tract and/or may be pre-installed and latched
together once the coil is implanted in the gastrointestinal tract.
The retainer 6105 may be adjustable or removable to facilitate
device removal (i.e., to permit the coil 6061 to be
straightened).
[0229] An illustrative, retainer embodiment is shown in the
enlarged view FIG. 26B. In this exemplary embodiment, the retainer
6105 has a body 6110 and a fastener 6115. The body 6110 is shaped
and sized to accommodate the number of coils or wires used (or
requiring attachment) in a particular configuration. The fastener
6115 is shown as a tab that attaches to the outer surface of the
body 6110. The retainer 6105 is formed from any of a wide variety
of durable biocompatible materials suited for use in the
environment of the stomach and compatible with the materials and
characteristics of the device and coil. Other configurations of the
retainer 6105 are possible. The specific shape and dimensions of
the retainer 6105 will vary depending upon the type of joining
technique used such as threaded connections, hook and loop
connections, spine joins or friction fits, as well as the delivery
method.
[0230] An alternative embodiment of a fastener for use with a
looped wire anchor is shown in FIG. 26C. The fastener 6617 can
include a split tube 6613 connected to the body of the coil 6061
and a ball 6619 and latch 6605 on a proximal end of the coil 6061.
The latch 6605 can include a distal-facing spring mechanism 6615
and a stopper 6623. To activate the fastener 6617, a grasper 6621
can be used to grab the ball 6619 and pull the distal end of the
coil 6061 in through the side of the split tube 6613. The ball 6613
can then be pulled proximally, compressing the spring arm 6615
until it slides through and proximal of the split tube and springs
back to an expanded state, catching the arm backside on the
shoulder of the split tube 6613. The split tube 6613 can thus be
caught between the spring mechanism 6615 and the stopper 6623,
thereby securing the coil 6061 to itself.
[0231] Alternative fastener designs are shown in FIGS. 37A-44B.
[0232] Referring to FIGS. 37A-37B, a fastener 7217 can include
extensions or teeth 7281 along a portion of the wire forming the
loop and a cinch mechanism 7283 configured to engage with the teeth
7281. The teeth 7281 can have proximally-facing sloped edges 7285
configured to allow the cinch mechanism 7283 to slide thereover and
edges 7287 that are more perpendicular to the wire that are
configured to hold the chinch mechanism 7283 in place. Accordingly,
as the proximal end 7289 of the anchor is pulled proximally, the
cinch mechanism 7283 will slide over the sloped edges 7283 to lock
the anchor in the desired diameter or configuration (as shown in
FIG. 37B, the further the proximal end is pulled, the smaller the
diameter loop can result). Thus, for example, a larger diameter can
be used to ensure that the loop is too large to pass through the
pylorus. The smaller diameter can be used for removal, for example
to make the loop small enough to be pulled through the esophagus.
Because the distal edges 7287 are approximately perpendicular to
the wire, distal pulling of the wire or anchor (such as by the
pylorus) will cause the cinching mechanism 7283 to hit the edges
7287 without sliding over, thereby locking loop or anchor in the
desired shaped. In some configurations, and as shown in FIGS.
37A-37B, the fastener 7217 can include a ball or other feature on
the proximal end 7289 to aid in grasping for locking while in the
stomach (for example, similar to the ball 6619 described with
reference to FIG. 26C).
[0233] Referring to FIGS. 38A-38C, a fastener 7317 can include a
spring 7381 attached at an attachment point 7383 along the loop
such that one end 7385 is unattached to the loop. The fastener 7317
can further include a ball 7319 on the free end of the loop. As
shown in FIG. 38B, as the loose end 7385 is pulled, the spring 7381
can open up or extend such that there is enough room between the
coils of the spring to fit the ball 7319 between two coils of the
spring. As pressure is released on the loosed end 7385 of the
spring 7381, the spring 7381 will spring back into shape, thereby
capturing the ball 7319 therein and locking the loop in place (as
shown in FIG. 38C). The fastener 7317 can be easily unlocked by
pulling on the loose end 7385 again, thereby opening the spring and
allowing the ball 7319 to be released.
[0234] Referring to FIGS. 39A-39B, a fastener 7417 can include an
eyelet 7481 on the loop and a barb 7483 on the free end of the
loop. The barb 7483 can include two pointed ends 7485 that cross
one another. After implantation in the gastrointestinal tract, the
center of the barb can be pushed into the eyelet 7481, causing the
pointed ends 7485 to splay apart and allow engagement with the
eyelet 7481. As the pointed ends 7585 pull back to cross over one
another, the barb 7483 will be caught in the eyelet 7481, thereby
locking the looped anchor in the desired configuration. To unlock
the fastener 7417, the free end can be pushed towards the eyelet
7481 such that the base of the hook slides up and over the top of
the eyelet 7481, allowing the hooks to fold inward and release the
lock.
[0235] Referring to FIGS. 40A-40B, another embodiment of a fastener
7517 includes a ball 7519 on the free end of the loop. The fastener
7517 further includes a locking mechanism 7583 on the loop. The
locking mechanism 7583 includes an extension 7585 having a slot
7587 therein. The slot can include one end having a larger diameter
than the ball 7519 and another end having a smaller diameter than
the ball 7519. The locking mechanism 7583 can be oriented such that
the smaller diameter portion is always closest to the ball (i.e.
such that the ball will want to fall into the small diameter
portion). The smaller diameter portion can be configured to snap
the ball 7519 therein to keep it from moving back and forth once in
place. To unlock the fastener 7517, the ball 7519 can be pulled or
pushed towards the larger diameter portion.
[0236] Referring to FIGS. 41A-41B, another embodiment of a fastener
7617 includes a spiral or helical curved portion 7681 on the free
end of the loop and a plurality of beads 7683 along a portion of
the loop. The helical portion 7681 can include the same number of
loops 7685 as the number of beads 7683. Further, the turn-to-turn
distance of the helix can match the gap between the beads 7683. The
loops 7685 can be configured to be captured between the beads 7683
to lock the looped anchor in place by twisting the free end with
the helix 7685 over the portion of the loop with the beads 7683.
The locking mechanism 7617 can be unlocked by twisting the free end
in the opposite direction. The fastener 7617 can further include a
ball 7619 configured to engage with a grasper to assist in locking
and unlocking the fastener 7617.
[0237] Referring to FIGS. 42A-42B, another embodiment of a fastener
7717 can include an eyelet 7781 on the free end of the loop 7783
and a post 7785 and tab feature (similar to Velcro) on the loop.
The eyelet 7781 can be extended over the tab 7783 (it will deflect
to allow the eyelet 7781 to extend thereover). Once over the tab
7783, the engagement of the tab 7783 with the top of the post 7785
will prevent the fastener 7717 from unlocking. To unlock the
fastener 7717, the eyelet 7781 can be pulled to deflect the post
7785, thereby releasing the eyelet 7781.
[0238] Referring to FIGS. 43A-43B, another embodiment of a fastener
7817 includes a hole 7883 extending through a free end of the loop.
The fastener further includes a post 7885 on the loop configured to
fit through the hole 7883. To lock the post 7885 into place inside
the hole 7883, a sleeve 7887 can extend over the engaged post 7885
and hole 7883. To unlock the fastener 7817, the sleeve can be slid
in the opposite direction.
[0239] Referring to FIGS. 44A-44B, another embodiment of a fastener
7917 includes an eyelet 7983 on a portion of the loop and a locking
mechanism 7981 on the free end of the loop. The locking mechanism
7981 includes a first bump 7935 having a diameter that is smaller
than the inner diameter of the eyelet 7983 (such that the first
bump 7935 can fit through the eyelet 7983 and a second bump 7933
having a diameter larger than the inner diameter of the eyelet 7983
(i.e. so that the second bump 7933 cannot fit through the eyelet
7983). The first bump 7935 can include a groove 7937 therein
configured to allow the free end of the wire to be directly
adjacent to the main wire, thereby allowing the first bump 7935 to
fit through the eyelet 7983. The first bump 7933 can have an outer
shape configured to match the inner circumference of the eyelet
7983 only in a specific orientation such that, once locked,
accidental unlocking of the fastener 7917 is unlikely. In some
embodiments, the eyelet 7983 can be malleable such that it can be
crushed after locking, thereby ensuring that the fastener will not
come unlocked during use.
[0240] Any of the locking mechanisms described herein with respect
to FIGS. 26A-26C and 37A-44B can be used in combination with any of
the anchoring systems described herein, but particularly with
respect to the anchors of FIGS. 25, 32-35, and 45-50.
[0241] Any of the above anchor embodiments can include one or more
"breaks" therein (such as breaks in the wire) configured to be
latched together once deployed in the gastrointestinal tract. Such
breaks in the anchor design can advantageously help avoid twisting
or tangling that can otherwise occur when the anchors are stretched
out for delivery or when the anchors are being removed. Such
twisting or tangling can due to: (1) portions of the anchor, such
as arches, turning in the same clockwise or counterclockwise
direction such that, when released, they want to preferentially
turn as well; and (2) releasing of the anchors in the opposite
direction of how they are loaded (device is pulled into a tube,
thereby causing it to rotate in one direction, and pushed out of
the tube, thereby rotating in the same direction again). Breaks in
the wire can help avoid this twisting. For example, referring to
FIGS. 49A-49C, an anchor 8401 can be designed similar to the anchor
7001 of FIG. 35. Rather than being a continuous anchor, however,
the anchor 8401 can include a break 8422 between one of the arches
8405a and the stem 8403. A latch 8417 (shown here as similar to the
fastener 6617 shown in FIG. 26C) can be used to close the break
8422 once the anchor 8401 is implanted. The latch 8417 can be any
of the latches described with respect to FIGS. 26A-26C and 37A-44B.
In some embodiments, twisting can also be avoided by releasing the
device in a proximal-to-distal manner.
[0242] In many of the illustrative embodiments of the device
described herein, the device is illustrated as having a latching
mechanism, retainer or fastener for attaching, joining or
releasably attaching one part of the device to another such as
shown in FIGS. 26A to 26C or in the various alternatives shown and
described in FIGS. 37-45 and 49A-49C, for example. It is to be
appreciated that the latching, fastening or attachment devices and
techniques may be modified for application to, for example,
reversibly join similar portions of a device. In this aspect, each
of the parts a particular fastening device embodiment is on the
same element or type of element. In one embodiment, any one or a
combination of the above described attachment devices or techniques
used to join a first portion of a coil to another portion of the
same coil or a different coil. In another embodiment, any one or a
combination of the above described attachment devices or techniques
used to join a first portion of an arch to another portion of the
same arch or a different arch. In still another embodiment, any one
or a combination of the above described attachment devices or
techniques used to join a first portion of a stem to another
portion of the same stem or a different stem. In still another
embodiment, any one or a combination of the above described
attachment devices or techniques used to join a first portion of a
counter arch to another portion of the same counter arch or a
different counter arch.
[0243] In still other embodiments, it is to be appreciated that the
attachment devices and techniques described such as shown in FIGS.
26A to 26C or in the various alternatives shown and described in
FIGS. 37-45 and 49A-49C, for example, may be modified for
application to reversibly join different portions of a device. In
this regard, it is to be appreciated that the latching, fastening
or attachment devices and techniques may be modified for
application to, for example, reversibly join different portions of
a device. In this aspect, each of the parts of a particular
fastening device embodiment are on a different element or type of
element. In one aspect, a portion of a coil may be attached to a
different coil, to a stem, to an arch, or to a counter arch. In
another aspect, a portion of a stem may be attached to another
stem, a coil, an arch or a counter arch. In still another aspect, a
portion of an arch may be attached to another arch, a stem, a coil,
or a counter arch. In still another alternative, a portion of a
counter arch may be attached to another counter arch, an arch, a
stem or a coil.
[0244] Single Wire Anchor Embodiments
[0245] As described above, the looped anchors of FIGS. 25, 32-35,
and 45-50 can be formed of a single continuous wire. Referring to
FIGS. 52A-52C, a wire for use in forming the anchor 7001 of FIG. 35
can include a thin portion 8791 at the distal end configured to
curl into a "pigtail"--like end, a stepped portion 8793 having a
stepped section of lower diameter configured to provide room to
fuse or bond the flow reduction sleeve thereto, a central portion
8799 configured to form the spine, and a stepped portion 8797
having a stepped section of lower diameter configured to provide a
bonding spot for a stopper (i.e. to stop the sleeve from extending
therepast). Further, the wire can include two sections 8792, 8794
that form the arches and coils as well as a necked down section
8796 that forms the pull wire of the anchor.
[0246] In some embodiments, such as FIGS. 32-35 and 46-50, the stem
of the proximal anchor can include two adjacent portions of wire.
As shown in FIG. 51, the stem 8703 can include a first section of
wire 8755, which can be continuous with the spine, adjacent to a
second section of wire 8757, which can be the end of the looped
portion of the anchor. The second section 8757 can end with a
sloped surface 8759 configured to create a smooth interface at the
junction between the two sections.
[0247] In some embodiments, as shown in FIG. 51, a sleeve 8795 can
be placed over a portion of the connection between the two sections
8755, 8757 to help bond the two sections together. In some
embodiments, the two sections 8755, 8757 can be welded together
while in other embodiments, the two sections 8755, 8757 can be
welded to the sleeve 8795.
[0248] In some embodiments, two wire sections of the stem can be
include flat surfaces that lay against one another to provide
stability at the junction. Referring to FIGS. 36A-36B, the two
sections 7181a,b of the stem 7103 each have a flat surface 7191a,b
that extends axially from the distal ends of the sections 7181a,b
to the start of the arches 7105a,b creating a `D` shaped
cross-section (see FIG. 36A). When the flat surfaces 7191a,b are
placed against one another, flat-against-flat, the total
circumference of the wires together can faun approximately an oval,
as shown in FIG. 36A. The two sections 7181a,b can be joined
securely with a tube 7195 that can have a length similar to the
length of the flat sections 7191a,b. The tube 7195 can assume an
oval shape so as to approximately assume the oval profile of the
flat sections 7191a,b. For example, the tube 7195 can be
elastically deformed to the proper shape. When the deforming force
is removed from the tube 7195, it will attempt to reassume its
unstressed round shape, thereby clamping the sections 7181a,b
together and preventing relative movement in both an axial and
radial manner.
[0249] As noted above with respect to FIG. 51B, the two wire
sections of the stem can be angled so that the transition from the
spine to the two arches is gradual, thereby providing a smooth
surface for the stomach tissue to reside against and a leading
device profile that is easier and less traumatic for the endoscope
working channel to deliver. Referring to FIGS. 36C-36D, the wire
section 7181a of an arch can have an angled surface, such as be
angled to a tip 7182a. The wire section 7181a can be positioned
such that the longer edge, i.e. the edge with the tip 7182a,
attaches to the adjoining distal end 7181b, thereby providing a
smooth transition along the outer edge of the distal end 7181a.
Further, the cut end can extend out fully out of the tube such that
there is space between the angle and the sleeve 7195 to provide
additional strength to the stem, i.e. to avoid having a weak point
right at the transition from the sleeve to a single wire forming
the stem 7103. Further, referring to FIG. 36E, the proximal ends
7181a,b can be attached together at an attachment point 7196 that
extends substantially all the way to the tip of the angled portion.
For example, the proximal ends (such as the free end and the main
wire from the spine) can be welded together. This attachment point
can be used with or without the tube 7195.
[0250] Referring to FIGS. 53A-53C, in some embodiments, the two
wire sections 8181a,b of the stem 8803 can be welded to an outer
sleeve rather than to one another. Each section can be welded to
the sleeve 8895 at positions 8802, 8804 substantially opposite the
junction of the two wires. This weld can help prevent the portions
of wire from twisting with respect to one another. Further, the
sleeve 8895 can be formed of a naturally cylindrical tube. As a
result, one placed around the sections, the tube will tend to want
to expand to its original shape, thereby placing an inward pressure
on the two sections 8181a,b to cause them to remain joined.
[0251] It is to be understood that the wire sections of the stem
can be joined in a variety of different ways. For example, the wire
sections can be twisted together, latched with any of the latching
mechanisms described herein, or bound together with a loose sleeve
that allows a wire end to slide along the main wire axially, but
remain in position radially.
[0252] Delivery of Looped Anchors
[0253] The looped anchors described herein, such as those described
with respect to FIGS. 25-26A, 32-35, and 45-50, can be delivered or
removed by straightening the anchor and pulling or pushing it with
a tool, directly into the esophagus, into a working channel of an
endoscope, or into an overtube or into another device configured
for removal.
[0254] In some configurations, the wire can include a pusher
against which a delivery tool can be pushed for delivery. For
example, referring to FIG. 32, the coil 6707 can include a pusher
3233, which can be an enlarged feature on the wire, configured to
provide support for pushing the collapsed anchor during delivery or
removal.
[0255] Referring to FIGS. 57A-D, one embodiment of a pusher 5733
can have a proximal barrel 5716, a distal annular shoulder 5714,
and a concentric lumen 5708 extending therethrough (such that the
lumen 5708 can surround the wire of the anchor). In use, the
delivery tool can be slid over the end of the wire forming the
anchor and over the proximal barrel 5716 of the pusher 5733 until
it bumps up against the shoulder 5714. The shoulder 5714 can thus
form a solid and larger surfaces area with which the delivery tool
can engage.
[0256] An alternate pusher embodiment is shown in FIGS. 58A-58E.
The pusher 5833 can include a proximal barrel 5816 and a distal
annular shoulder 5814. An off-center lumen 5808 extends
therethrough, and a notch or v-groove 5810 extends axially along
the side of the pusher 5833 opposite the lumen 5808. The pusher
5833 can be used, for example in double arch configurations where
two extend side-by side (the v-groove 5810 can provide space for
the additional wire). In use, the delivery tool can be slid over
the end of the wire forming the anchor and over the proximal barrel
5816 of the pusher 5833 until it bumps up against the shoulder
5814. The shoulder 5714 can thus form a solid and larger surfaces
area with which the delivery tool can engage.
[0257] Secondary Anchoring in the Bulb
[0258] In some embodiments, referring to FIGS. 54 and 55, a
secondary anchor can be configured to be placed in the duodenal
bulb. Referring to FIG. 54, the bulb anchor 8901 can have a
diameter of between 1 and 2 inches, such as approximately 1.2
inches. Bulb anchors can have a variety of shapes. For example, as
shown in FIG. 54, the anchor 8901 can have an extended diamond
shape. Alternatively, as shown in FIG. 55, the bulb anchor 9001 can
have an inverted umbrella shape. The inverted shape would
preferentially oppose distal device travel by resisting collapse.
The secondary anchor in the duodenal bulb can be used alone or in
conjunction with any of the proximal anchors described herein.
Additional Exemplary Embodiments
[0259] FIGS. 27A-27D illustrate device alternatives having a shaped
proximal portion and a floppy distal portion. The floppy distal
portion can provide for less peristalsis to grab onto. The proximal
device 20P remains similar in design and construction to those
described above in FIG. 15. There is a spine 6250 and coiled end
61. The proximal portion 20P has at its distal end a joint,
transition or attachment 6205, depending upon the particular
configuration of the device. The proximal portion may take on any
of the configurations described herein, such as FIGS. 19, 20, 21 or
others. The device portion distal to the transition 6205 is floppy
in that it will bend, curve and/or flex according to the bending,
curvature or flexure of the surrounding anatomy. The floppy portion
of the device includes a spine or central member 6255 extending
from the transition point 6205 and ending with terminal end 6261.
In some embodiments, the terminal end 6261 can be weighted to help
prevent retrograde migration, i.e. to help keep the device from
moving back into the stomach.
[0260] The device embodiments illustrated in FIGS. 27A-27D are
shown with a plurality of flow reduction elements 200. Other
configurations are possible including more or fewer flow reduction
elements or no flow reduction elements as well as the inclusion of
one or more of the capabilities described above for drug delivery,
data collection or delivery of other therapies. The length of the
floppy distal portion may vary.
[0261] FIG. 27B illustrates the device in place within the anatomy
where the length of the floppy distal position places the terminal
end 6261 adjacent or nearly so to the proximal end as described and
illustrated in FIG. 17. The terminal end 6161 is near the end of
the horizontal duodenum 10C or within the junction 14.
[0262] FIG. 27C is an alternative embodiment of the device having a
longer distal portion similar to that illustrated and described in
FIGS. 76, 22, and 23. In this embodiment, the terminal end 6261 is
beyond the flexure 14 and within the jejunum 12 of FIG. 27B with a
longer distal length.
[0263] FIG. 27D is an alternative embodiment of the device having a
shorted distal portion. In this embodiment, the length of the shaft
6255 places the terminal end 6261 within the descending duodenum
10B or horizontal duodenum 10C.
[0264] FIGS. 28A, 28B and 29 relate to alterative embodiments of
lockable segmented devices or devices configured to be actuated in
order to shift between flexible and fixed configurations. The
locking segment aspects of FIGS. 28A, 28B and 29 may be modified
according to the lockable element designs described in, for
example, U.S. Pat. No. 3,546,961 entitled "Variable Flexibility
Tether," incorporated herein by reference in its entirety.
[0265] FIG. 28A illustrates an unlocked segment of a device having
a plurality of links 6310 on either side of joints 6315. The
proximal and distal ends are removed for clarity in this view but
are illustrated in the full device view of FIG. 28B. Returning to
FIG. 28A, the opposing faces of an adjacent link 6310 and joint
6315 may be shafted for cooperative mating. A tensioning member or
control cable 6320 extends through the links 6310 and joints 6315.
When the cable 6320 is not under tension, adjacent links and joints
move freely. Whenever the tensioning cable 6320 is shortened,
adjacent links and joints are placed into compression and locked
into their orientation. As a result of locking the adjacent links
and joints, the overall shape of the device is fixed. In the
illustrative embodiments of FIGS. 28A and 28B, the links 6310 are
all of the same length and dimension. FIG. 28B illustrates a device
having the links and joints of FIG. 28A with proximal and distal
coils 61 attached to a spine or central portion 50. The central
portion 50 may run through each of the joints and links along with
the control cable or the spine 50 may be configured to function as
the control cable. Upon delivery in a slack state (i.e., FIG. 28A),
the device is permitted to enter into the desired portion of the
anatomy until it conforms as desired to the surrounding anatomy.
Thereafter, the control cable may be engaged to lock the links and
joints into place to hold the device in the desired position. FIG.
28B provides a section view of the distal esophagus, stomach,
duodenum & proximal jujunem that illustrates a device in the
locked position that conforms to the shape of the stomach and
duodenum.
[0266] FIG. 29 illustrates an embodiment of a shape locked device
of the invention in relation to the esophagus 2, the stomach 4, the
duodenum 10, and the jejunum 12. The relevant anatomy is described
elsewhere in FIGS. 1, 9 and 13, for example, and similar reference
numbers are used here. FIG. 29 is an alternative shape lock device
to the one illustrated in FIGS. 28A and 28B. In contrast the shape
lock device in FIG. 28A, 28B, the links 6310 in this embodiment may
include links of the same or different sizes. In this embodiment,
the size and shape of the locking elements need not be uniform. In
contrast, the elements may have different shapes or sizes to
accommodate the surrounding anatomy for implant. More of fewer
links may be used to approximate the shape of the anatomy in the
desired implant region. The length of the links 6310 may be
selected based upon approximate lengths or fractions thereof of the
various portions of the anatomy such as the duodenal bulb, the
descending duodenum, the horizontal duodenum, ascending duodenum or
the jejunum. In one aspect, the length, dimensions or
characteristics of one or more links 6310 in the device may be
adjusted or selected based upon the expected location of that link
within the anatomy. One or more links may be selected based upon
the desired property of the device in that area. In still another
alternative embodiment, the locking interaction between the links
and the joints may not be the same along the length of the device.
In this way, even when locked, some links and joints will remain
loose to permit accommodation of adjacent curved anatomy or to
relieve pressure points that may develop is the device is too
rigid.
[0267] One or more of the aspects of the features described in
FIGS. 28A, 28B or 29 such as a tensioning member 6320, link 6310 or
joint 6315 may be added to or included into modified version of the
segmented device embodiments described herein. In some embodiments,
the spine is segmented into substantially straight segments, that
may be adapted to form a basis of a link 6310 design. Some
embodiments include a spine with three segments such as, for
example, the embodiment illustrated in FIGS. 4 and 9. Still other
embodiments include a spine with more than three segments such as,
for example, FIG. 3. Still other embodiments include a segment or
segments that assume a more curvilinear faun such as, for example,
the devices shown in Figures, 44, 46, 47, 48, and 51.
[0268] Referring to FIGS. 56A and 56B, the shape-locked
configurations can be used to lock an anchor in a desired
configuration as well. Thus, for example, the anchor 5601 can begin
as a loose set of individuals segments 5621 connected, for example,
by a tension cord 5623. The segments 5621 can include angled edges
5625 specifically configured to interact with one another to
achieve the desired shape upon locking, as shown in FIG. 56B.
[0269] In these and other embodiments, additional alternative
configurations and embodiments are possible. In one aspect, one or
both of the proximal and distal ends of a device may include the
same or different terminating ends. For example, many embodiments
illustrate the proximal and distal ends each having a coiled end 61
as shown and described in FIG. 15. The ends may be terminated in a
different way however in other embodiments. Any one of the terminal
ends described above in, for example, in FIGS. 84A-88 may be used
or no terminal end may be provided, such as in FIG. 72, 74 or 76
and others.
[0270] In other aspects, the cross sectional shape of the spine or
central support may be circular, oval, oblong, rectangular,
polygonal, or other shape selected to adjust the ability of the
device to conform to the implant location or resist the forces
caused by peristaltic action. In still other aspects, the cross
section shape of the spine or central support is formed into
sections having different shapes comporting to different anatomical
implant locations. For example, a terminal end and proximal section
that resides in the stomach may have one cross section shape that
is different from the central portion and distal end of the same
device that resides within the duodenum. Similarly, the cross
section shape of the device may vary according to one or more of
the portions of the duodenum 10 such as the bulb, descending,
horizontal, ascending or even the jejunum or between one or more of
the transition areas between these portions.
[0271] In many of the illustrative embodiments of the device
described herein, the device is illustrated with or described as
including a spine 50. It is to be appreciated that the spine 50 may
be used with or without flow reduction elements or other
capabilities such as those described herein such as for drug
delivery, stimulation, flow obstruction, lipid retention or other
capabilities as described above. Likewise, in the illustrative
embodiments of the device having one or more flow reduction
elements, it is to be appreciated that the spine 50 may be used
with more or fewer flow reduction elements or without flow
reduction elements. Additionally or alternatively, a device may
include one or more of the other additional capabilities such as,
for example, drug delivery, application of stimulation or
modulation signals, flow obstruction through a portion of the
alimentary canal where the device is placed, lipid retention or
other capabilities described herein. Moreover, while the spine is
illustrated in some embodiments as a solid wire, alternative
embodiments are possible and within the scope of the invention. In
some embodiments, the spine may be a hollow, flexible tube such as
illustrated in, for example, FIGS. 3, 4, 5, 7, 9, 10, and 11. In
another embodiment, the spine can be a hollow, flexible tube in any
of a number of different sizes, shapes or diameters. For example,
the spine may be a flexible tube of a larger diameter, such as
those found in a duodenal sleeve. In one aspect, the diameter of
the spine is about the same size and the internal diameter of a
duodenum, a portion of a duodenum or a portion of the alimentary
canal where the spine is positioned. In still another embodiment,
the spine may be a hollow tube of a smaller diameter such as in a
configuration similar to a flexible cord, such as a string. Still
further spine alternatives the spine includes any structure
attached to an embodiment of an anchor that suspends itself or any
other device attached to it intended to remain and/or hang in the
duodenum, or portion of an intestine and/or a portion of the
alimentary canal. In still further configurations, the spine,
hollow tube, flexible cord or string is sized and shaped for
placement in the desired therapy location and is formed from any of
the materials described herein.
[0272] In many of the illustrative embodiments of the device
described herein, the device is illustrated having one or more flow
reduction elements or other structure to modify the passage of a
fluid around or through the device as shown, for example, in FIGS.
3, 4, 5, 6, 9, 10, 11, 15, 17, 18, 22, 27A-27D 35A, 54 and 55. In
some embodiments, a device may be illustrated and described with a
bare spine such as, for example, in FIGS. 19, 20, 21, 23, 24, 25,
26A, 30A-34C, 45, 47C, and 48B. It is to be appreciated that
various illustrative embodiments having a bare spine may be
modified to include one or more elements alone or in any
combination of the flow modifying elements shown and described in
any one or more of FIGS. 3, 4, 5, 6, 9, 10, 11, 15, 17, 18, 22,
27A-27D 35A, 54 and 55.
[0273] In many of the illustrative embodiments of the device
described herein, the device is illustrated having a particular
type of anchor on one end or both ends of the device. In some
illustrative embodiments, a portion of a device is shown without
any anchoring device. It is to be appreciated that the various
device embodiments described herein may be combined in a number of
different ways depending upon the requirements of a specific
application, therapy or anatomical site for delivery of therapy or
anchoring the device. As such, the embodiments shown and described
in, for example, FIGS. 3, 4, 5, 6, 7, 9, 10, 11 could be used with
one or more of the anchors shown and described in any of FIGS.
15-23, 25A, 25B, 27A-27D or as shown and described in FIGS.
32A-35D, and 45-50. In still other alternative configurations, the
proximal portion, anchor or section 20P may be removed, modified or
replaced by an anchor embodiment as shown and described, for
example, in one or more of FIGS. 32A-35D, and 45-50.
Terms and Conventions
[0274] Unless defined otherwise, all technical terms used herein
have the same meanings as commonly understood by one of ordinary
skill in the art of gastrointestinal interventional technologies.
Specific methods, devices, and materials are described in this
application, but any methods and materials similar or equivalent to
those described herein can be used in the practice of the present
invention. While embodiments of the invention have been described
in some detail and by way of exemplary illustrations, such
illustration is for purposes of clarity of understanding only, and
is not intended to be limiting. Still further, it should be
understood that the invention is not limited to the embodiments
that have been set forth for purposes of exemplification, but is to
be defined only by a fair reading of claims that are appended to
the patent application, including the full range of equivalency to
which each element thereof is entitled.
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