SATIATION DEVICES AND METHODS
A device for inducing weight loss in a patient includes a tubular prosthesis positionable at the gastro-esophageal junction region, preferably below the z-line. In a method for inducing weight loss, the prosthesis is placed such that an opening at its proximal end receives masticated food from the esophagus, and such that the masticated food passes through the pouch and into the stomach via an opening in its distal end.
This application is a continuation of U.S. patent application Ser. No. 10/751,751, filed Jan. 5, 2004, which claims the benefit of U.S. patent application Ser. No. 10/118,289, filed Apr. 8, 2002, which is a continuation-in-part of U.S. patent application Ser. No. 09/940,110, filed Aug. 27, 2001. claims the benefit of U.S. application Ser. No. 09/940,110, filed Aug. 27, 2001.
FIELD OF THE INVENTIONThe present invention relates generally to the field of devices and methods for achieving weight loss in humans, and specifically to the use of devices implantable within the human stomach for controlling feelings of hunger.
BACKGROUND OF THE INVENTIONVarious medical approaches are used for controlling obesity. These approaches include diet, medication, and surgical procedures. One of the more successful surgical procedures is the vertical banded gastroplexy or the proximal gastric pouch with a Roux-en-Y anastomosis that shunts food from the proximal region of the stomach into the intestine, thereby minimizing absorption of food into the bloodstream. However, known complications are present with each of these procedures and more successful options are desired.
Other alternatives include implantation of gastric balloons that prevent overeating by occupying volume within the stomach. Unfortunately, gastric balloons can migrate down the GI tract, causing obstruction and thus necessitating removal.
It is therefore desirable to provide a successful and minimally-invasive alternative to existing approaches for controlling obesity.
SUMMARY OF THE INVENTIONA satiation device utilizing principles of the present invention includes a tubular pouch positionable at the gastro-esophageal junction. The pouch has a proximal opening for receiving ingested food from the esophagus, and a distal opening for releasing food from the pouch into the stomach. The pouch is proportioned such that release of food from the pouch in to the stomach occurs relatively slowly, causing food to accumulate within the pouch so as to give the patient the sensation of fullness.
An anatomical view of a human stomach S and associated features is shown in
Various embodiments of satiation devices are described herein. Many of these devices include a pouch or funnel positioned at the gastro-esophageal junction region so as to form a small reservoir which collects masticated food from the esophagus—thereby limiting the amount of food that can be consumed at one time. Over time the food within this reservoir descends into the stomach through a distal opening in the pouch. The pouch may optionally include a tubular extension positionable within the esophagus to facilitate flow of food from the esophagus into the pouch.
Materials that may be used for the pouch include flexible materials that will prevent passage of food through the sides of the pouch. Examples of such materials include, but are not limited to polyesters (e.g., Dacron® polyester), ePTFE fabric (e.g., GoreTex® fabric or others), a polyurethane such as ChronoFlex® polyurethane, nylon fabrics, silicone, other polymeric materials, and bio-absorbable materials (e.g., PLLA, PGA, PCL, poly-amhydride, etc). The pouch 12 may be formed of a composite of compliant, semi-compliant and/or non-compliant materials which give different regions of the pouch different degrees of compliance so as to allow/limit expansion of the pouch in various locations. For example, it may be desirable to provide the pouch with a fairly elastic exit port to as to prevent occlusion in the event a large piece of food is ingested, whereas the proximal end of the pouch may be stiffer to prevent bulging. Varying degrees of compliance may also be built into the pouch by varying the cross-sectional thickness of the pouch in different regions of the pouch. The pouch material may be coated with a lubricious, bio-compatible, chemically inert material, such as paraleyne, to reduce friction on the base.
The flexible pouch material may be carried by a supporting structure, such as a soft mesh, coil, a cage structure, ribs, rings etc. The supporting structure may be formed of stainless steel, polymer, shape memory materials (such as nitinol, shape memory alloys, or shape memory polymers), bio-absorbable materials or, in the case of a silicone pouch, thickened regions of silicone. The supporting structure may be located at the interior or exterior of the flexible pouch material. It may be molded into or sewn to the pouch material, or it may be attached using a suitable adhesive. If a tightly woven mesh or tightly wound coil is provided, the flexible pouch material may be eliminated. Alternatively, a mesh may be provided having a polymeric material embedded in the interstices of the mesh, in which case a separate internal or external covering of pouch material may be eliminated.
The pouch is preferably constructed so as to be self-expanding, such that the pouch springs radially open into an expanded condition upon ejection from a deployment device or catheter as more fully described below.
In many of the embodiments, the pouch is formed to have a funnel shape. However, a variety of alternative shapes may be used for the pouch. For example, the pouch may have a much shorter proximal-to-distal dimension and thus take the shape of a shallow saucer with a small hole on its bottom surface. Other examples include, but are not limited to, egg shapes, other tapered shapes such as the shape of a “spinning top”, cylindrical shapes, and other symmetrical or asymmetrical shapes.
The device may be modular in that where multiple components are to be implanted, the various components may be provided separately from one another. In such a modular system, the separately implanted components may be attached to one another within the body during implantation, or certain ones of them may remain unattached to one another even after implantation. Alternatively, the physician may assemble the components to one another just prior to implantation. Modular components are desirable in that they permit the physician to select sizes for each component that are appropriate for the patient.
One embodiment of a satiation device is illustrated in
Because of its small volume (which may be on the order of approximately 2 cc-300 cc in volume, but is preferably in the range of 10-30 cc), the pouch functions to limit the amount of food that can be consumed at one time.
Pouch 12 may be formed of a flexible material that will prevent passage of food through the sides of the pouch, such as Dacron® polyester, silicone, or other polymeric material. The pouch 12 may be formed of a composite of compliant, semi-compliant and/or non-compliant materials which give different regions of the pouch different degrees of compliance. Such a composite would allow/limit expansion of the pouch in various locations, so as to help control the passage rate of food material through the pouch and/or the exit pressure of the food from the pouch. If silicone is used, varying degrees of compliance may be built into the pouch by varying the cross-sectional thickness of the pouch in different regions of the pouch. The pouch material may be coated with a lubricious, bio-compatible, chemically inert material, such as paraleyne, to reduce friction on the base material's surface which will help prevent sticking and food build up on the device.
During implantation the pouch 12 is secured at the gastro-esophageal junction region G using sutures, clips, adhesives or other suitable means. Although the pouch may be secured to the esophageal tissue, it is more preferable to apply sutures/clips below the Z-line to allow for attachment to the thicker tissue of the stomach wall. Suture attachment points, which may take the form of holes, eyelets or grommets 20 in the pouch may be used to provide reinforced regions for anchoring the sutures. Although as few or as many of such suture/clip attachment points as needed may be used, at least four such points are desirable, such as at 90° intervals around the pouch, so as to enable the pouch to be secured around the full circumference of the tissue. The suture attachment points may be made of a suitably dense radio-opaque material, such as titanium or gold, to add in visualization of the device during or after the procedure. Each suture attachment point may also be marked using a different color to facilitate identification and orientation of sutures. If the pouch is formed of silicone, the proximal portion of the pouch (in which the eyelets 20 are located) may be formed of more durable material such as a woven material, Dacron® polyester or ePTFE fabric in lieu of silicone so as to provide a more durable sewing region. Although grommets, eyelets or reinforced regions may be advantageous, the pouch may alternatively be provided without suture attachment points formed of special materials (with or without identifying markings)—in which case the sutures are passed directly through the pouch material.
The flexible pouch material may be carried by supporting members, such as a soft mesh, a cage structure, ribs, rings etc. The supporting members may be formed of stainless steel, polymer, shape memory materials such as nitinol, shape memory alloys, or shape memory polymers, or thickened regions of pouch material. The pouch is preferably constructed so as to be self-expanding, such that the pouch springs radially open into an expanded condition upon ejection from a deployment device or catheter as more fully described below.
Pusher tube 26 is an elongate tube extending through the sheath 24 and extending slightly from the proximal end of the sheath 24. A handle 30 may be formed at the proximal end of the pusher tube 26 to facilitate movement of the pusher tube relative to the sheath 24. Pusher tube 26 includes a central lumen 32 for receiving devices that may be needed at the implantation site. Such devices may include, for example, an endoscope 34 to provide visualization of the implant procedure, or other devices if needed to ensure proper placement of the implant. A plurality of circumferential lumen 36 (
Referring to
The distal end of sheath 24 is passed through the esophagus and into the stomach. The free distal ends of the suture strands 40 are sewn through the tissue surrounding the esophageal opening, preferably just below the Z line. The sutures may be attached under endoscopic guidance if desired, using conventional suturing techniques. See
Once the sutures have been secured to the tissue, the pusher tube 26 is advanced in a distal direction using handle 30. Pusher tube 26 drives the pouch 12 out the distal opening of the sheath 24. The sheath 24 is positioned with the eyelets 20 at the suture location as shown in
Once implanted, the pouch limits passage of food from the patient's esophagus into the stomach. It is believed that as food collects and backs up in the reservoir of the pouch, baroreceptors in the fundus of the stomach and in the gastro-esophageal junction region will trigger a feeling of satiation. Gravity and columnar force will propel food through the reservoir's restricted orifice and into the stomach where normal digestion will occur.
A third pouch 54 is shown in
As shown in
To facilitate suturing of a pouch such as those described herein, it may be desirable to form pleats in the tissue at the gastro-esophageal junction region using sutures—in a manner similar to the pleating or “cinching” procedure performed as a treatment for gastro-intestinal reflux disease. Such tissue pleats are preferably formed in the stomach tissue below the z-line, and extend radially inwardly from the stomach walls by a small amount. These folds are more easily accessed by a suture needle or clips during attachment of the pouch and thus facilitate implantation of a pouch.
Two alternative mechanisms for forming plications in the stomach tissue are shown in
To plicate tissue at the gastro-esophageal junction region using the device of
Another plication device is shown in
Referring to
The distal end of pouch 90 tapers into a chute 96. Chute 96 may be formed of a material similar to that of the pouch, or it may be formed of an elastic polymer, such as a low durometer polyethylene, silicone, elastic polyurethane materials etc. that permits radial expansion of the chute. Such expansion in response to a buildup of food material bearing against the chute may be desirable so as to prevent blockages in the chute. The chute 96 may be collapsible and thereby function as a check valve—preventing reflux of material from the stomach back into the pouch.
An annular sewing region 98 is positioned at the proximal end of the pouch. During implantation, sutures are connected to the sewing region and secured to adjacent tissue. To facilitate suturing of the pouch in place, it may be desirable to form tissue pleats at the gastro-esophageal junction region using sutures—in a manner similar to the pleating or “cinching” procedure performed as a treatment for gastro-intestinal reflux disease. Such tissue pleats extend radially inwardly from the stomach walls by a small amount, and thus can be easily accessed by a suture needle or clips during attachment of the pouch.
Pouch 90 may be provided with a delivery system that includes an elongate mandrel 100 extending through the pouch 90. A nose cone 102 is attached to the distal end of the mandrel, and includes a guidewire 104. Nose cone 102 is preferably flexible and free of sharp or blunt edges so as to prevent tissue trauma during implantation.
As shown in
When the pouch is to be implanted, the sheath 106 (with the pouch inside) is introduced into the esophagus, with the guidewire 104 passing first through the esophagus and into the stomach. Once the sewing region 98 has reached the gastro-esophageal junction region, sheath 106 is withdrawn, causing the pouch to spring to the expanded position shown in
Referring to
As with the other pouches described herein, pouches 108, 120 of
A stomach pouch may alternatively be one portion of a larger satiation device. For example, referring to
Additionally, the pouch 125 (as used with or without cage 126) may also be attached at its proximal end to an alignment extension 128. Referring to
Yet another embodiment of a pouch device is shown in
Supporting members such as circumferential rings 132 and/or longitudinal ribs 134 (
A neck 136 is positioned at the proximal end of the pouch 130 and is positionable within the gastro-esophageal junction region. During implantation the neck 136 is secured to the surrounding esophageal tissue and/or stomach tissue using sutures or clips. Suture holes, eyelets or grommets 138 in the neck 136 may be used to provide reinforced regions for anchoring the sutures. In addition, the reinforced locations and materials may be made of a suitably dense radio-opaque material, such as titanium or gold, to add in visualization of the device during or after the procedure. The reinforced locations and material may be of different colors to add in identification and orientation of sutures also. If desired, all or portion of the neck 340 may be formed of a woven material in lieu of silicone so as to provide a more durable sewing region.
A chute 140 is formed at the distal end of the pouch 130. Chute 140 may include supporting members such as ribs 134 (or rings such as rings 132) to provide rigidity to the chute. Alternatively, a collapsible chute such as chute 140a shown in
Fixation of the funnel device at the gastro-esophageal junction region may also be achieved by using bio-compatible adhesives, thermal fusion, or radio-frequency activated fixation.
The pouch 130, and each of the pouches described herein, may be delivered to the gastro-esophageal junction region using a delivery system such as the one described in connection with
During use, the delivery device 142 is caused to engage the edge of the pouch (such as pouch 130) at the proximal or distal or end of the pouch. As the claws 144 are closed, they fold the end of the pouch with which they are engaged and draw the pouch towards (or, optionally, into) the sleeve 146. If the claws are used to engage the distal end of the pouch as shown in
Stomach pouches may alternatively be used as standalone devices without sutures—and may instead be held in place by the radial expansion forces of struts, mesh or coils forming part of the pouch structure. An example of such a pouch 150 is shown in
A funnel portion 158 is provided at the distal end of the pouch. As with previous embodiments, when the pouch is implanted the neck 152 is disposed within the gastro-esophageal junction region (e.g., in the distal esophagus as shown) and the funnel portion 158 extends into the stomach.
Prior to implantation, the pouch 150 is preferably packaged within a sheath (not shown) with all of the rings in the compressed position shown in
Two embodiments of trans-esophageal satiation devices are shown in
The proximal portion 170 of the pouch (which sits in a proximal position relative to the esophageal sphincter) may include a self-expanding cylindrical stent structure that is formed of shape memory material such as nitinol, shape-memory polymer, or shape-memory alloy and that exerts radial pressure against the surrounding walls so as to hold itself in place within the esophagus. The stent may include barbs in its exterior surface to ensure that the pouch 168 does not move out of place. Alternatively, the proximal portion 172 may instead be attached to the surrounding walls using sutures or barbs. According to this alternative, the pouch may include a stent structure or be provided without.
The embodiment of
Satiation pouches may be configured to allow the size of the pouch's distal opening to be increased or decreased. This enables a physician implanting such a device to set the distal opening to a size appropriate for a patient. In some cases, it will also allow the physician to make adjustments to the distal opening after it has been implanted. For example, if the patient is not losing weight at a desired rate, the physician might reduce the size of the distal opening—so that food will empty more slowly from the pouch into the stomach. The physician might alternatively increase the size of the distal opening if necessary if weight loss is occurring too rapidly.
Referring to
Referring to
Many techniques may be used to remove a satiation pouch from the stomach. One example is shown in
Next, a sheath 204 is passed through the esophagus to the gastro-esophageal junction region. A retrieval device 206 having expandable claws 208 (that may be similar to those of the device of
Referring to
Various embodiments of satiation device have been described herein. These embodiments are giving 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 may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, implantation locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the invention.
Any and all patents and applications referenced herein, including for purposes of priority, are hereby incorporated by reference.
Claims
1. A gastroesophageal implant system, comprising:
- an implant;
- a plicator endoscopically engageable with stomach wall tissue to form a tissue plication; and
- an anchor adapted to be coupled to a stomach wall plication formed using the plicator, and to be coupled to the implant to retain the implant within the stomach.
2. The implant system of claim 1, wherein at least one of the implant and the anchor is a ring.
3. The system of claim 1, further including an endoscope extendable through a mouth of the patient and into the stomach, the endoscope operable to provide visualization of the implant and connector during implantation of the implant and the anchor.
4. The system according to claim 2, wherein the implant is a ring and further comprises a mesh wall attached to the ring.
5. The implant system of claim 1, wherein the implant, when coupled to the stomach wall plication, defines a restricted flow path from a first stomach region proximal to the implant to a second stomach region distal to the implant.
6. The implant system of claim 1, wherein the anchor is a clip.
7. The implant system of claim 1, wherein the plicator is a vacuum plicator.
8. A method for inducing weight loss in a patient, comprising the steps of:
- endoscopically forming a tissue plication within a stomach;
- coupling a first implant to the tissue plication;
- retaining the first implant within the stomach such that a first section of the stomach is proximal to the implant and a second section of the stomach is distal to the implant;
- wherein food ingested by the patient flows from the first section to the second section.
9. The method of claim 6, wherein the first implant is a flow-restrictive implant, and wherein food ingested by the patient flows through the flow-restrictive device from the first section to the second section.
10. The method of claim 8, further including after coupling the first implant, coupling a second implant to the first implant.
11. A system for limiting food intake by a patient, the system comprising:
- a flow-restrictive implant implantable within the stomach such that a first section of the stomach is proximal to the implant and a second section of the stomach is distal to the implant, the implant defining a flow path such that ingested food flows from the first section, through the flow path, and into the second section; and
- a connector adapted to couple to tissue within the stomach, the connector engageable with the implant to retain the implant within the stomach;
- wherein a portion of the implant is selectively moveable to alter the cross-sectional area of the flow path.
12. The system according to claim 11, wherein implant is a tubular device defined by a wall, wherein the wall is band expandable to increase the cross-sectional area and retractable to decrease the cross-section area.
13. A method of implanting a stomach implant, comprising the steps of:
- endoscopically coupling at least one elongate element to a stomach interior;
- threading a proximal portion of the elongate element through a stomach implant; and
- advancing the stomach implant over the elongate element and into contact with the stomach interior.
14. The method according to claim 13, wherein coupling the elongate element includes coupling the elongate element to a plication formed in stomach wall tissue.
15. The method according to claim 13, wherein the method further includes endoscopically coupling a plurality of elongate elements to plications formed in stomach wall tissue, threading each elongate element through a corresponding anchor point in the stomach implant.
16. The method according to claim 13, wherein threading of the proximal portion of the elongate element is performed outside the body.
17. The method according to claim 13, wherein the elongate element is a suture.
Type: Application
Filed: Dec 18, 2007
Publication Date: Aug 28, 2008
Inventors: Richard S. STACK (Chapel Hill, NC), Richard A. GLENN (Chapel Hill, NC), William L. Athas (Durham, NC), Michael S. Williams (Santa Rosa, CA)
Application Number: 11/958,587
International Classification: A61F 2/04 (20060101);