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Weight Loss Patent Abstract
Described herein is a system for inducing weight loss in a patient,
which comprises an extragastric space occupier positionable in contact
with an exterior surface of a stomach wall to form an inward protrusion
of wall into the stomach, and a retention device positionable in
contact with the wall to retain the inward protrusion and to thereby
capture the extragastric space occupier within the protrusion.
Weight Loss Patent Claims
What is claimed is:
1. A system for inducing weight loss in a patient, the system comprising:
an extragastric space occupier positionable in contact with an exterior
surface of a stomach wall to form an inward protrusion of wall into
the stomach; and a retention device positionable in contact with
the wall to retain the inward protrusion and to thereby capture
the extragastric space occupier within the protrusion.
2. The system according to claim 1, wherein the extragastric space
occupier is proportioned to cause the protrusion to fill a portion
of the stomach, thereby causing the patient to feel full.
3. The system according to claim 1, wherein the extragastric space
occupier has in expandable within the stomach to an expanded volume
in the range of 200-800 cc.
4. The system according to claim 1, wherein the extragastric space
occupier is proportioned to cause the protrusion to create a restriction
in the stomach that will slow the rate at which food can descend
from the esophagus into the stomach.
5. The system according to claim 1, wherein the retention device
comprises at least one suture.
6. The system according to claim 1, wherein the retention device
comprises at least one staple.
7. The system according to claim 1, wherein the retention device
comprises at least one band positionable around the protrusion within
the stomach.
8. The system according to claim 7, wherein the band is positionable
encircling the protrusion.
9. The system according to claim 7, wherein the band is inflatable.
10. The system according to claim 1, wherein the extragastric space
occupier is inflatable.
11. The system according to claim 1, wherein the extragastric space
occupier includes an inflation port, and wherein the system includes
an inflation needle extendable through the esophagus into the stomach,
the inflation needle engageable with the inflation port.
12. The system according to claim 11, wherein the inflation port
is extendable through an opening in the stomach wall.
13. The system according to claim 11, wherein the inflation port
includes a resealable portion of the extragastric space occupier,
and wherein the needle is extendable through the stomach wall into
engagement with the inflation port.
14. The system according to claim 1, further including instructions
setting forth a method for implanting the system, including the
steps of: positioning the extragastric space occupier into contact
with an exterior of a wall of the stomach, causing the wall to protrude
inwardly into the stomach; coupling a retention device to the stomach
so as to retain the inward protrusion and to thereby capture the
extragastric space occupier within the protrusion.
15. The system according to claim 14, wherein the instructions
set forth that the positioning step includes the step of passing
the extragastric space occupier through the esophagus into the stomach,
and then passing the extragastric space occupier through an opening
formed in the wall of the stomach and into contact with the exterior
of the wall.
16. The system according to claim 14, wherein the instructions
set forth that the positioning step includes the step of passing
the extragastric space occupier laparoscopically into an abdominal
cavity and into contact with the exterior of the wall.
17. A method of assisting weight loss in a patient, comprising
the steps of: positioning an extragastric space occupier into contact
with an exterior surface of a stomach wall to form an inward protrusion
of wall into the stomach; and placing a retention device in contact
with the wall to retain the inward protrusion and to thereby capture
the extragastric space occupier within the protrusion.
18. The method of claim 17, wherein the placing step places the
retention device into contact with an interior surface of the wall.
19. The method of claim 18, wherein the retention device comprises
a band and wherein the placing step includes encircling the protrusion
using the band.
20. The method of claim 17, wherein the placing step includes the
step of drawing portions of the wall into contact with one another
and attaching a retention device to the wall to retain the protrusion.
21. The method of claim 20, wherein the retention device comprises
at least one suture or staple.
22. The method of claim 17, wherein the extragastric space occupier
is expandable, and wherein the method includes the step of expanding
the space occupier to a volume sufficient to cause the protrusion
to fill a portion of the stomach, thereby causing the patient to
feel full.
23. The method of claim 22, wherein the expanding step includes
expanding the space occupier to a volume in the range of 200-800
cc.
24. The method of claim 17, wherein the space occupier is expandable,
and wherein the method includes the step of expanding the space
occupier to cause the protrusion to create a restriction in the
stomach that will slow the rate at which food can descend from the
esophagus into the stomach.
25. The method of claim 17, wherein the space occupier includes
an inflation port, and wherein the method includes the step of passing
an inflation needle extendable through the esophagus into the stomach,
engaging inflation port with the inflation needle, and inflating
the space occupier using the inflation needle.
26. The method of claim 25, wherein the positioning step includes
positioning the inflation port to extend an opening in the stomach
wall.
27. The method of claim 25, wherein the inflation port includes
a resealable portion of the space occupier, and engaging step includes
passing the needle through the stomach wall into engagement with
the inflation port.
28. The method of claim 17, wherein the positioning step includes
passing the extragastric space occupier through the esophagus into
the stomach, and then passing the extragastric space occupier through
an opening formed in the wall of the stomach and into contact with
the exterior of the wall.
29. The method of claim 17, wherein the positioning step includes
passing the extragastric space occupier laparoscopically into an
abdominal cavity and into contact with the exterior of the wall.
Weight Loss Patent Description
PRIORITY CLAIM
[0001] This application claims priority from prior provisional
application Ser. No. 60/565,378, filed Apr. 26, 2004, and which
is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of
implants for inducing weight loss in patients, and specifically
to devices and methods for reducing the effective volume of a patient's
stomach and or creating restrictions to slow passage of food into
the stomach.
BACKGROUND OF THE INVENTION
[0003] An anatomical view of a human stomach S and associated features
is shown in FIG. 1A. The esophagus E delivers food from the mouth
to the proximal portion of the stomach S. The z-line or gastro-esophageal
junction Z is the irregularly-shaped border between the thin tissue
of the esophagus and the thicker tissue of the stomach wall. The
gastro-esophageal junction region G is the region encompassing the
distal portion of the esophagus E, the z-line, and the proximal
portion of the stomach S.
[0004] Stomach S includes a fundus F at its proximal end and an
antrum A at its distal end. Antrum A feeds into the pylorus P which
attaches to the duodenum D, the proximal region of the small intestine.
Within the pylorus P is a sphincter that prevents backflow of food
from the duodenum D into the stomach. The middle region of the small
intestine, positioned distally of the duodenum D, is the jejunum
J.
[0005] FIG. 1B illustrates the tissue layers forming the stomach
wall. The outermost layer is the serosal layer or "serosa"
S and the innermost layer, lining the stomach interior, is the mucosal
layer or "mucosa" MUC. The submucosa SM and the multi-layer
muscularis M lie between the mucosa and the serosa.
[0006] Prior art treatments for obesity range from diet and medication
to highly invasive surgical procedures. Some of the more successful
surgical procedures are the vertical banded gastroplexy or the proximal
gastric pouch with a Roux-en-Y anastomosis. However, known complications
are present with each of these procedures. More successful and less
invasive options are desired.
[0007] A less invasive prior art treatment for obesity includes
implantation of a gastric balloon delivered into the stomach via
the esophagus. The balloon is an obstructive device--it prevents
overeating by occupying volume within the stomach. Although implantation
of a gastric balloon is less invasive than other surgical procedures,
gastric balloons can migrate down the GI tract, causing obstruction
and thus necessitating removal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1A is a schematic illustration of a human stomach and
a portion of the small intestine.
[0009] FIG. 1B is a cross-sectional perspective view of a portion
of a stomach wall, illustrating the layers of tissue forming the
wall.
[0010] FIG. 2 is a cross-section view of a stomach illustrating
positioning of an obstructive implant.
[0011] FIG. 3. is a cross-section view of a stomach illustrating
positioning of two obstructive implants.
[0012] FIG. 4 is a cross-section view of a stomach illustrating
positioning of an obstructive implant in the antral region of the
stomach.
[0013] FIG. 5 is a cross-section view of a stomach illustrating
positioning of an obstructive implant in the fundal region of the
stomach.
[0014] FIG. 6 is a cross-section view of a stomach illustrating
alternative positioning of two obstructive implants FIG. 7 is a
cross-section view of a stomach illustrating positioning of an irregularly-shaped
obstructive implant.
[0015] FIG. 8 is a cross-section view of a stomach illustrating
positioning of an elongate obstructive implant.
[0016] FIG. 9. is a cross-section view of a stomach illustrating
positioning of an obstructive implant having an alternative shape.
[0017] FIGS. 10-12A are perspective views of alternative configurations
for obstructive implants. FIG. 12B illustrates the implant of FIG.
12A positioned in the stomach.
[0018] FIGS. 13A through 13F are a sequence of drawings illustrating
endoscopic implantation of an obstructive implant. FIG. 13G is an
implantation step that is an alternative to the step shown in FIG.
13F.
[0019] FIG. 14 is a cross-section view of a stomach illustrating
use of a force-distributing retention band with an obstructive implant.
[0020] FIG. 15 is a cross-section view of a stomach illustrating
use of an alternative force-distributing retention band with an
obstructive implant.
[0021] FIGS. 16 through 18 are cross-section views of a stomach
illustrating alternate retention methods for obstructive implants.
[0022] FIG. 19 illustrates an obstructive implant having a subcutaneous
inflation port.
[0023] FIGS. 20 and 21 illustrate use of obstructive implants to
facilitate retention of other obesity-controlling devices within
the stomach.
DETAILED DESCRIPTION OF THE DRAWINGS
[0024] Referring to FIG. 2, an obstructive implant 10 includes
a body positioned against the exterior of the stomach wall W. The
implant occupies stomach volume by causing a portion of the stomach
wall W to bulge into the interior volume of the stomach, thus reducing
the effective volume of the stomach interior and reducing stomach
capacity. Because the implant 10 is positioned outside the stomach,
it cannot migrate into the intestinal tract creating obstructions.
A retention band 12 is positioned within the stomach encircling
a portion of the wall W so as to retain the implant 10 within pocket
2 as shown. The retention band 12 may be a ring that is elastic
or inelastic, flexible or fairly rigid. The diameter of the retention
band 12 may be adjustable if desired. The retention band 12 is preferably
proportioned such that in the event the band becomes free within
the stomach, it can pass through the intestinal system without incident.
Thus, the retention device is preferably of a size that will not
on its own to occupy sufficient space within the stomach to create
feelings of satiety, but that relies on the extragastric implant
10 to reduce stomach capacity. Nonetheless, in alternate embodiments
the retention band 12 may also perform a space-occupying function,
and/or a restrictive and/or obstructive function.
[0025] Various positions for the implant are illustrated in the
drawings. Depending on the size and positioning of the implant,
it may function as an obstructive device, a restrictive device,
or both. In some embodiments, the implant may have an expanded volume
in the range of approximately 200-700 cc, sufficient to cause the
inwardly-protruding to fill a portion of the stomach, thereby causing
the patient to feel full and thus limiting food intake. In FIG.
2, the implant is positioned to function as an obstructive device
(i.e. to occupy space so as to reduce effective stomach volume),
but also to create a restriction 14 in the stomach. The restriction
14 is a narrowed region of the stomach, which slows the rate at
which food can descend from the esophagus into the stomach. Food
may accumulate in the region above the restriction, causing the
patient to experience feelings of satiety and thus limiting food
intake, and/or limiting the amount of food a patient can consume
at one time.
[0026] FIG. 3 shows a pair of implants 10 and a pair of retention
bands 12 positioned in the proximal stomach to create a restriction
14a. This restriction 14a may also minimize reflux and thus function
as treatment for patients suffering from gastro-intestinal reflux
disease (GERD).
[0027] FIG. 4 illustrates that the implant 10 may be positioned
in the antrum A. It may similarly be positioned at the pylorus P
(see FIG. 1A). Alternatively, the implant 10 may be positioned in
the fundus F as shown in FIG. 5 again creating an obstruction as
well as an (optional) restriction 14b in the proximal stomach. The
original position of the wall of the fundus F is illustrated in
dashed lines.
[0028] FIG. 6 illustrates that a pair of implants 10 may be positioned
against regions of stomach wall W1, W2 on opposite sides of the
stomach. These implants are retained in their respective pockets
2 using a single retention band 12 encircling both regions of wall
W1, W2 to create an obstruction within the stomach and which creates
restricted flow paths on opposite sides of the obstruction.
[0029] The configuration illustrated in FIG. 6 is particularly
advantageous in that it relies in part on adhesion of the serosal
tissue lining the outer surface of the stomach. It has been found
that serosal tissue layers can adhere to form relatively strong
bonds when held in apposition to one another. Other embodiments
including, but not limited to, the FIG. 2-5, 7 and 8 embodiments
may be modified to allow the retention band to retain regions of
serosal tissue into contact with one another such that over time
the serosal tissue will adhere as a permanent means for retaining
the implant 10. For example, if such a modification was made to
the FIG. 2 embodiment, the regions R1, R2 of stomach wall would
be drawn into contact with one other, and retention band 12 would
retain that contact until the serosal layers adhered to one another.
At that time, the retention band (or other retention devices such
as sutures, staples, etc.) could be removed from the stomach, such
that no device remained in the stomach interior, and the implant
remained in the protrusion formed against the exterior stomach wall.
It may be further desirable in such embodiments to inflate the implant
during a later procedure performed after the serosal layers have
adhered to one another. In such embodiments, inflation may be carried
out using a needle introduced into the stomach, used to pierce the
stomach wall, and then passed into an inflation port (e.g. such
as port 26 of FIG. 2 or valve 48 of FIG. 13G). Alternatively, the
balloon may be self-sealing (similar to self-sealing tires), also
allowing inflation/deflation of the balloon using a needle that
pierces the stomach wall and the balloon.
[0030] A section of reinforcing and/or ingrowth-promoting material
15 (FIG. 6) may be optionally placed between serosal and/or mucosal
tissue layers that are positioned in contact with one another. The
material may be a synthetic or non-synthetic mesh, porous material,
slotted material, or any other material through which adhesions
will form or onto which tissue will grow. Examples include, but
are not limited to, polypropylene, materials sold under the trade
names Goretex or Dacron, or tissue graft material such as the Surgisis
material sold by Wilson Cook Medical, Inc. The material may be treated
with tissue-ingrowth promoting substances such as biologics. If
such material is used, the adhesions that form between the serosal
tissue layers will pass through and/or onto the interstices of the
material and serve to reinforce the bond between the tissue layers.
The material may further cause some mechanical abrasion of the adjacent
tissue, creating additional scar tissue that would further reinforce
the strength of the opposed tissue.
[0031] If adhesion of adjacent mucosal tissue surfaces is desired,
modification of the interior tissue surface may further be needed
in order to optimize adhesion of opposed regions of internal stomach
tissue. In particular, it is believed that better adhesion of the
interior wall surfaces may be achieved when a portion of the mucosal
layer of tissue lining the stomach interior is removed, such that
the tissue surfaces sutured in apposition to one another are serosal,
sub-mucosal or muscularis layers. It is believed that opposed layers
of mucosal tissue do not adhere together as well as opposed layers
of serosal, sub-mucosal, or muscularis tissue. Surface modification
methods for promoting such tissue adhesion include cutting, ablating
(using RF, laser, or chemical ablation) or abrading the mucosal
surface within the stomach as indicated by dashed lines. This modification
is ideally performed before the folds are placed in apposition.
Depending on the depth to which cutting, ablation or abrasion is
performed, the sub-mucosal, musclaris, or serosal layer beneath
the mucosal layer is exposed. This allows the exposed regions of
tissue to be placed in apposition and causes the opposed surfaces
to tightly adhere over time.
[0032] Although the implants shown in FIGS. 2-6 are illustrated
as being spherical, various other configurations may be used. For
example, an alternate implant 10a shown in FIG. 7 may include a
recess 16 along its surface such that the portion of the stomach
wall W following the contour of recess 16 creates a form of pouch
or reservoir 18 in the stomach within which food may accumulate.
An elongate implant 10b of the type shown in FIG. 8 may be used
to form an elongate restriction 20 while greatly reducing the effective
volume of the stomach. FIG. 9 shows an implant 10c having a modified
hourglass configuration including an obstructive portion 22 that
functions to bulge the stomach wall inwardly as described in connection
with earlier embodiments. A neck 24 extending from the obstructive
portion 22 connects with a base portion 26 that helps to distribute
forces imparted against the stomach W and prevents tissue erosion
and/or migration of the implant. As shown in the figure, the retention
band 12 preferably seats against the stomach tissue surrounding
the neck 24.
[0033] Many other shapes beyond those shown in this application
may be used for the implant (such as for accommodating the shape
of the anatomy, or for creating a restriction or obstruction of
a particular size/shape), without departing from the scope of the
present invention.
[0034] There are likewise many suitable structures and materials
useful for the implant. Some structures and materials are shown
and described herein, although again many others may be used without
exceeding the scope of the present invention.
[0035] For example, the implant may be an elastic or inelastic
balloon that is implantable in a deflated state and then inflated
within the body using a gas or liquid. A balloon of this type may
include a port such as port 26 shown in FIG. 2. During use an inflation
needle may be introduced into the stomach, used to pierce the stomach
wall, and then passed into the port 26. The needle may be used to
introduce inflation medium into the balloon, or to deflate the balloon
if adjustments in balloon size are needed. Alternatively, the balloon
may be self-sealing (along the lines of puncture-proof or self-sealing
tires), also allowing inflation/deflation of the balloon using a
needle that pierces the stomach wall and the balloon. This latter
embodiment is advantageous in that it does not necessitate a particular
orientation for the balloon as would be needed to orient an inflation
port for receipt of an inflation needle.
[0036] Other configurations besides balloons are also suitable
for the implant. The implant 10d may have fluted walls 28 as shown
in FIG. 10, or it may be formed of a mesh 30 as shown in FIG. 11.
These implants 10d, 10e may be self-expanding or they may be provided
in a fully expanded form. The implant 10f of FIG. 12A includes a
pair of plates 32 separated by a neck 34. When positioned as shown
in FIG. 12B, a portion of the stomach wall W caves into the gap
36 between the plates 32, creating a flow path for food moving from
the esophagus E into the stomach. The amount of restriction provided
by the implant 10f may be selected by selecting a suitable length
or width for the neck 34.
[0037] The implant need not be a hollow structure, but could instead
be entirely solid.
[0038] The implant may be implanted endoscopically using tools
passed into the stomach via the esophagus. According to the endoscopic
approach, the implant is inserted into the stomach and then passed
through an opening formed in the stomach wall. Alternatively, a
laparoscopic method may be used to pass the implant into the abdominal
cavity through incisions or trocar punctures in the skin. The implant
may also be introduced using an open surgical approach. In both
the laparoscopic and surgical procedures, the retention band 12
is preferably introduced endoscopically into the stomach.
[0039] FIGS. 13A through 13F illustrate one method of positioning
an inflatable implant using an endoscopic approach. Referring to
FIG. 13A, retention band 12 is inserted down the esophagus into
the stomach using an endoscopic instrument 38. Next, the implant
10 is passed into the stomach and through the retention band 12
as shown in FIG. 13B. Implant 10 is preferably compressed within
a tubular instrument 40 having a tissue-piercing distal end. The
instrument 40 may be telescopically disposed within a tubular sheath
42 to prevent the instrument from inadvertently nicking surrounding
tissue. Although not shown, an inflation tube extends through the
instrument 40 and sheath 42 and is coupled to an inflation port
of the implant. An endoscope 44 is used to monitor the procedure.
[0040] Referring to FIG. 13C, the tissue-piercing instrument 40
is extended from its sheath and used to pierce through the stomach
wall W at a desired implant location. The implant 10 is released
from the instrument 40 and partially inflated by passing inflation
medium through the inflation tube. The tissue-piercing instrument
40 and its sheath 42 may be removed from the stomach, leaving the
inflation tube 46 (FIG. 13D) behind.
[0041] Next, tension is applied to the inflation tube 46 to pull
the implant 10 towards the stomach so as to create the pocket 2.
This step draws the implant 10 and the surrounding stomach wall
through the retention band 12 as shown in FIG. 13D. Once a sufficient
amount of tissue has been drawn through the retention band, the
implant is inflated to the desired size as shown in FIG. 13E. The
inflation tube 46 is detached from the implant 10 and the endoscopic
instrument 38 is detached from the retention band 12, leaving the
implant in place as shown in FIG. 13F. The hole formed in the stomach
wall may be closed using sutures or a sealable gel that solidifies
when placed into contact with the tissue.
[0042] Referring to FIG. 13G, it should be noted that the implant
may include an inflation valve 48 that is left extending through
the stomach wall. The valve 48 allows for post-implant size adjustments
by allowing inflation medium to be added to or removed from the
balloon using an inflation tube passed through the esophagus and
attached to the valve. If removal of the balloon is required, the
valve may be grasped using endoscopic instruments to draw the balloon
back into the stomach and out the esophagus. The valve may be surrounded
by a seal to prevent movement of stomach contents into the abdominal
space outside the stomach. A gel of a type that will solidify when
placed into contact with the stomach surface may be used for this
purpose.
[0043] The retention band 12 may take alternate forms or be replaced
altogether using other types of structures that help to capture
the implant 10 in the pocket 2 at the implant site. FIG. 14 illustrates
that the cross-sectional area of the restrictive band 12a may be
large relative to the size of the implant so as to diffuse the forces
imparted on the region of stomach wall captured between the band
12a and the implant 10 and to thereby prevent erosion of, or damage
to, the stomach tissue. FIG. 15 illustrates that a large surface-area
retention liner 12b may alternatively be used so as to distribute
forces over a broader surface. Referring to FIG. 16, the restriction
ring 12c and implant 10 may be coupled together by an inflation
tube 50 extending through the stomach wall. A valve 52 is fluidly
coupled to the tube 50 and allows for introduction/removal of inflation
medium using an inflation needed passed into the stomach. The valve
52 and tube 50 facilitate explantation of the implant using a grasping
instrument inserted through the esophagus and into the stomach.
[0044] The retention band itself may be inflatable. Referring to
FIG. 17B, the retention band may include separate inflatable chambers
54a, 54b each having an inflation port 56a, 56b. The chambers 54a,
54b are joined together to form an annular band. The upper chamber
54a may be shaped to form a channel 58 for passage of food, as shown
in FIG. 17B.
[0045] FIG. 18 illustrates that the retention band may be eliminated
entirely. As shown, after the implant 10 is pulled against the stomach
wall W, stomach tissue adjacent to the pocket 2 can be fastened
together using pledgets 60 (or sutures, staples, clips or other
means). Over time, a physiological response will cause the regions
of serosal tissue held in contact with one another to bond together,
thereby retaining the implant in the pocket 2.
[0046] Referring to FIG. 19, inflatable implant 10 may be tethered
to an inflation port 62 positioned within a subcutaneous pocket
in the body. If needed following implantation, an inflation needle
may be inserted through the patient's skin and into the inflation
port 62 to increase or decrease the amount of inflation medium within
the implant.
[0047] Referring to FIGS. 20 and 21, it should be noted that while
the implant 10 may itself provide restriction and/or obstruction,
the implant 10 may also be used to prevent migration of a restrictive
and/or obstructive device positioned inside the stomach. For example,
device 64 of FIG. 20 or device 66 of FIG. 21 may be positioned in
the proximal stomach and seat against the portion of the stomach
wall that protrudes inwardly as a result of implant 10.
[0048] Components of the type described herein may be supplied
individually or as systems which may include various combinations
of components such as implants (e.g. implant 10), retention devices
(e.g. band 12), implantation instruments, and/or instructions for
use. If included, instructions for use may include instructions
instructing a user to implant the implant using methods such as
any of those described above. For example, the instructions may
instruct the user to create an inward protrusion in the stomach
wall such as by positioning an instrument or the implant against
an exterior surface of the stomach wall. The instructions may further
instruct the user to position the retention device in a manner that
at least partially retains the protrusion in the wall and that thus
captures implant within the protrusion, externally of the stomach.
In some embodiments where a retention band is provided, the instructions
for use may instruct the user to encircle a portion of the protrusion
in the wall with the retention band. The instructions may instruct
the user as to laparoscopic, endoscopic, and/or open surgical approaches
such as those described above.
[0049] Various components and methods have been described herein.
These embodiments are given by way of example and are not intended
to limit the scope of the present invention. It should be appreciated,
moreover, that the various features of the embodiments that have
been described might be combined in various ways to produce numerous
additional embodiments |