US20090012554A1 - Devices and methods for treatment of obesity - Google Patents

Abstract

Methods, devices, tools and assemblies for treating a patient to effect weight loss. One method embodiment involves passing a device including an expandable member in a collapsed configuration and a buoyancy member through an opening in the skin of a patient and into the abdominal cavity of the patient, and anchoring at least a portion of the expandable member, relative to at least one structure in the abdominal cavity. Devices including at least one expandable member and at least one buoyancy member are provided.

Description

CROSS-REFERENCE
• This application is a continuation-in-part application of co-pending application Ser. No. 11/407,701, filed Apr. 19, 2006, which is hereby incorporated herein by reference thereto, in its entirety, and to which application we claim priority under 35 USC §120.
• This application claims the benefit of U.S. Provisional Application No. 60/833,284, filed Jul. 24, 2006, and U.S. Provisional Application No. 60/877,595, filed Dec. 28, 2006, both of which applications are hereby incorporated herein, in their entireties, by reference thereto.
• This application also hereby incorporates herein by reference thereto, in its entirety, co-pending application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2) filed on even date herewith, and titled “Devices and Methods for Treatment of Obesity”.
FIELD OF THE INVENTION
• The present invention relates to treatment of obesity, more particularly to implantable devices and methods of implanting the devices in the abdominal cavity to treat an obese patient.
BACKGROUND OF THE INVENTION
• Obesity has become a major health concern, both nationally and internationally. The National Center for Health Statistics (NCHS) estimates that over 120 million Americans are overweight, including about 56% of the adult population. Of these, about 52 million are considered obese, as measured by a body mass index (BMI) of 30 or greater. In Europe, an estimated 77 million people are obese, as measured by the same standard. This problem is not limited to western nations, as many developing countries are reported to have obesity rates over 75% of the adult population.
• Co-morbidities that are associated with obesity include, but are not limited to type II Diabetes, high blood pressure, sleep apnea, stroke and arthritis, the symptoms of which often tend to be lessened or alleviated upon loss of weight by a person so affected.
• In the U.S., options for treatment of obesity are currently quite limited. Current treatment methodologies typically rely upon surgically introducing a “malabsorptive” environment in the gastro-intestinal tract, a restrictive environment, or a combination of these. One available treatment method is gastric bypass surgery and another is referred to as gastric banding (one of these techniques is referred to as the LAPBAND™ procedure). These procedures are limited to only those patients with a BMI over 40 (or over 35, with co-morbidities present).
• Gastric bypass procedures incur a great deal of morbidity and create a malabsorptive state in the patient by bypassing a large portion of the intestines. Serious side effects, such as liver failure have been associated with this procedure, as well as chronic diarrhea. Another surgical procedure that has a high degree of morbidity associated with it is known as the “Gastric Bypass Roux-en-Y” procedure. This procedure reduces the capacity of the stomach by creating a smaller stomach pouch. The small space holds only about one ounce of fluid. A tiny stomach outlet is also surgically created to slow the speed at which food leaves the stomach. Staples are used to create a small (15 to 20 cc) stomach pouch, with the rest of the stomach being stapled completely shut and divided from the stomach pouch. The small intestine is divided just beyond the duodenum, brought up, and connected to the newly formed stomach pouch. In addition to the considerable morbidity associated with this procedure, other disadvantages include “dumping syndrome”, where stomach contents are literally “dumped” rapidly into the small intestine which may lead to nausea, weakness, sweating, faintness, and diarrhea; hernias resulting from the surgery; gallstones; leakage of the connection between the pouch and the intestine; stretching of the pouch that was formed; nutritional deficiencies; and possible dehiscence of the staples.
• The LAPBAND™ is a band that, when placed, encircles the fundus-cardia junction and is inflatable to constrict the same. It does not reduce the volume of the stomach, but rather restricts passage of food into the stomach, the theory being that the patient will feel satiety with a much smaller volume of food than previously. Although the LAPBAND™ procedure is less invasive than a gastric bypass procedure, it also typically achieves less weight loss. Further, it is not a simple procedure and requires a substantial amount of training by a surgeon to become proficient in performing the procedure. Also, a substantial amount of dissecting and suturing is required because the pathway by which the band is introduced is not an existing pathway, and must be established by dissection. Great care is required to avoid blood vessels and nerves that may be in the intended pathway to be created by the dissection. After placing the band around the fundus-cardia junction, the ends of the band must be connected together and then it must be cinched down into place. Additionally, complications such as erosion at the fundus-cardia junction, slippage of the band from its intended location, nausea/vomiting, gastroesophageal reflux, dysphagia and lack of effectiveness in causing weight loss have been reported.
• Intragastric balloons have also been placed, in an attempt to fill a portion of the volume in the stomach, with the theory being that it will then require less food than previously, to give the patient a sensation of fullness or satiety. This procedure involves delivery of a balloon (typically, transorally) to the interior of the stomach and inflation of the balloon to take up a portion of the volume inside the stomach. However, intragastric balloons may also lead to complications such as obstruction, vomiting and/or mucosal erosion of the inner lining of the stomach. The balloon can break down over extended exposure to the stomach's acids, and in some cases, after breaking down, the balloon translated through the intestines and caused a bowel obstruction.
• Gastrointestinal sleeves have been implanted to line the stomach and/or a portion of the small intestines to reduce the absorptive capabilities of the small intestine and/or to reduce the volume in the stomach, by reducing the available volume to the tubular structure of the graft running therethrough. Although weight loss may be effective while these types of devices are properly functioning, there are complications with anchoring the device within the stomach/GI tract, as the stomach and GI tract function to break down things that enter into them and to move/transport them through. Accordingly, the integrity of the anchoring of the device, as well as the device itself may be compromised over time by the acids and actions of the stomach and GI tract.
• A sleeve gastrectomy is an operation in which the left side of the stomach is surgically removed. This results in a much reduced stomach which is substantially tubular and may take on the shape of a banana. This procedure is associated with a high degree of morbidity, as a large portion of the stomach is surgically removed. Additionally, there are risks of complications such as dehiscence of the staple line where the staples are installed to close the surgical incisions where the portion of the stomach was removed. Further, the procedure is not reversible.
• In the laparoscopic duodenal switch, the size of the stomach is reduced in similar manner to that performed in a sleeve gastrectomy. Additionally, approximately half of the small intestine is bypassed and the stomach is reconnected to the shortened small intestine. This procedure suffers from the same complications as the sleeve gastrectomy, and even greater morbidity is associated with this procedure due to the additional intestinal bypass that needs to be performed. Still further, complications associated with malabsorption may also present themselves.
• An inflatable gastric device is disclosed in U.S. Pat. No. 4,246,893, in which a balloon is inserted anteriorly of the stomach and posteriorly of the left lobe of the liver. The balloon is then inflated to compress the stomach so that it fills with less food that would ordinarily be possible. Not only does this device compress the stomach, but it also compresses the liver, as seen inFIG. 5 of the patent, which may cause complications with the liver function. Additionally, the balloon is simply placed into this location, and there is no assurance that it will not migrate and lose its effectiveness in compressing the stomach to the degree intended. Still further, the balloon is of a simple spherical design, and, as such, extends pressure outwardly in all directions, 360 degrees, in all planes. Accordingly, the liver is compressed just as much as the stomach is. Also, the compression forces against the stomach are not ideal, as the spherical balloon conformation does not match the conformation of the expanding stomach. The stomach is not spherical when expanded, or concave with a constant radius of curvature, but expands into a designated space that allows the fundus to expand preferentially more than other parts of the stomach.
• Brazzini et al. in WO2005/18417 discloses at least two or more expandable devices used to treat obesity, in which the devices are inserted through the abdominal wall and anchored against the external surface of the stomach wall by an anchoring mechanism that extends through the stomach wall and fixes to the internal surface of the stomach wall.
• U.S. Patent Publication No. 2005/0261712 to Balbierz et al. describes capturing a device against the outer surface of the stomach wall to form a restriction that appears to function similarly to the restriction imposed by the LAPBAND™. The anchoring of the devices disclosed relies upon placement of features against the internal wall of the stomach to form an interlock with the device which is placed against the external wall of the stomach. U.S. Patent Publication Nos. 2005/0267533 and 2006/0212053 to Gertner disclose devices for treatment of obesity that use one or more anchoring mechanisms that are passed through the wall of the stomach to establish an anchor.
• U.S. Pat. No. 6,981,978 to Gannoe discloses devices for reducing the internal cavity of the stomach to a much smaller volume, which may be used to carry out a bypass procedure. Stapling is employed to isolate the smaller volume in the stomach, and thus the same potential disadvantages are present as with other stapling procedures described herein.
• U.S. Pat. No. 6,186,149 to Pacella et al. describes an occluder device that can be used as a dietary control device (seeFIG. 8C). The occluder device is placed against the wall of the stomach and inflated to press inwardly on the stomach wall. A frame is wrapped around the stomach wall and is inflated to press against the stomach wall. However, there is no disclosure of how the frame might be adjusted to maintain a position relative to the stomach wall as the size of the stomach varies.
• Gastric reduction techniques have been attempted, such as by inserting instruments trans-orally and reducing the volume of the stomach by stapling portions of it together. However, this technique is prone to failure due to the staples pulling through the tissues that they are meant to bind.
• Techniques referred to as gastric pacing endeavor to use electrical stimulation to simulate the normal feedback mechanisms of a patient that signal the brain that the patient is full, or satiated. While these techniques are less invasive than some of the other existing treatments, statistics to date have shown that the amount of weight lost by using such techniques is less than satisfactory.
• Currently marketed drugs for weight loss, such as XENICAL®, MERIDIA® and Phen fen have largely failed, due to unacceptable side effects and complications, and sometimes to an ineffective amount of weight loss. Other drugs that are on the horizon include ACCOMPLIA® and SYMLIN®, but these are, as yet, unproven.
• The risk and invasiveness factors of currently available surgeries are often too great for a patient to accept to undergo surgical treatment for his/her obesity. Accordingly, there is a need for less invasive, yet effective surgical treatment procedures for morbidly obese patients (patients having a BMI of 35 or greater). Also, since the current surgical procedures are currently indicated only for those patients having a BMI of 40 or greater, or35 or greater when co-morbidities are present, it would be desirable to provide a surgical procedure that would be available for slightly less obese patients, e.g., patients having a BMI of 30 to 35 who are not indicated for the currently available surgical procedures. It would further be desirable to provide a surgical procedure that would be indicated for obese patients having a BMI in the range of 30-35, as well as for more obese patients.
SUMMARY OF THE INVENTION
• The present invention provides methods, devices, tools and assemblies for treating a patient to assist with weight loss. One method embodiment involves passing a device including an expandable member in a collapsed configuration and a buoyancy member into the abdominal cavity of the patient, and anchoring at least a portion of the expandable member, relative to at least one structure in the abdominal cavity.
• A method of treating a patient is provided that includes the steps of: passing a device into the abdominal cavity of the patient, wherein the device includes at least one attachment member extending from a main body portion thereof; positioning an inferior portion of the device in the abdominal cavity; and anchoring that at least one attachment member to an inner surface of the abdominal wall.
• A method of treating a patient is provided that includes steps of: passing a guide rail into the abdominal cavity of the patient; passing an anchoring frame, guided by the guide rail, into the abdominal cavity; anchoring the anchoring frame to at least one structure in the abdominal cavity; passing a device, guided by the guide rail, into the abdominal cavity; and attaching the device to the anchoring frame.
• A method of treating a patient is provided that includes steps of: passing a guide rail into the abdominal cavity of the patient, wherein the guide rail is selected from one of: at least one guidewire; at least one flexible wire facilitating viewing out of a distal end portion thereof from a proximal end portion thereof; at least one rod; or a flexible steerable catheter; passing an anchoring frame, guided by the guide rail, into the abdominal cavity; anchoring the anchoring frame to at least one structure in the abdominal cavity; passing a device, guided by the guide rail, into the abdominal cavity; and attaching the device to the anchoring frame.
• A method of treating a patient is provided, including steps of: passing an anchoring frame into the abdominal cavity of the patient; delivering anchoring members, attached to the anchoring frame, through at least one structure in the abdominal cavity that the anchoring frame is to be anchored to, through the skin and out of the patient; fixing the anchoring members externally of the abdominal cavity to anchor the anchoring frame to the at least one structure in the abdominal cavity; passing a device, into the abdominal cavity; and attaching the device to the anchoring frame.
• A method of treating a patient is provided, including steps of: passing a buoyancy member into the abdominal cavity of the patient; anchoring the buoyancy member to at least one structure in the abdominal cavity; passing a device into the abdominal cavity; and attaching the device to the buoyancy member.
• A method of treating a patient is provided, including steps of: passing a device including an expandable member having at least one trans-abdominally detectable marker; advancing the device into the abdominal cavity of the patient while tracking and guiding the advancing by trans-abdominally detecting the location of the at least one marker, relative to the patient's anatomy, as the device is advanced; and anchoring at least a portion of the expandable member, relative to at least one structure in the abdominal cavity.
• A method of monitoring functionality of a device implanted in the abdominal cavity of a patient to enhance weight loss is provided, including: providing a handheld monitoring device outside of the patient; and wirelessly communicating with at least one sensor on the device located in the abdominal cavity.
• A method of treating a patient is provided, including: providing a device implanted in the abdominal cavity of the patient, wherein the device occupies a space in the abdominal cavity to perform at least one of: prevention of expansion of the stomach of the patient into the space and compression of a portion of the stomach; wherein the device includes at least one electrode on a surface thereof in contact with the stomach of the patient, said at least one electrode being electrically connected to a stimulation signal controller; and delivering a stimulation signal from the controller to the at least one electrode to stimulate at least one contraction of at least one muscle in the stomach.
• A method of treating a patient is provided, including: passing a device into the abdominal cavity of the patient; anchoring at least a portion of the device, relative to at least one structure in the abdominal cavity; and occupying a space in the abdominal cavity with the device to substantially restrict expansion of the fundus of the stomach, and restraining the stomach to a shape resembling a tube, but wherein at least a portion of the antrum is left unrestrained.
• A method of treating a patient is provided, including: passing a device into the abdominal cavity of the patient; anchoring at least a portion of the device, relative to at least one structure in the abdominal cavity; and occupying a space in the abdominal cavity with the device to substantially restrict expansion of the fundus of the stomach, and restraining the stomach to a shape resembling a tube, but wherein a small pouch is left unrestrained at a superior end portion of the stomach.
• An implantable device for treatment of a patient to assist weight loss is provided, wherein the device includes: an expandable member configured to be positioned in an abdominal cavity of the patient, the expandable member configured to be expanded from a contracted configuration to an expanded configuration after placement of the device in the abdominal cavity, and to substantially maintain a size and shape of the expanded configuration. The expandable member, in the expanded configuration, has a buoyancy characteristic relative to its surrounding when implanted in the abdominal cavity. The device further includes a buoyancy member having a buoyancy characteristic different from the buoyancy characteristic of the expandable member, to alter a combined buoyancy characteristic of the device.
• A method of making an implantable device for treatment of a patient to assist weight loss is provided, wherein the device includes an expandable member configured to be positioned in an abdominal cavity of the patient, the expandable member configured to be expanded from a contracted configuration to an expanded configuration after placement of the device in the abdominal cavity, and to substantially maintain a size and shape of the expanded configuration, and a buoyancy member fixed to the expandable member and contained within an internal cavity of the expandable member. The method of making includes: providing a mold having a shape of the buoyancy member integral with a shape of the expandable member; molding a wall of polymeric material over the mold; removing the molded wall of material from the mold; inverting a molded buoyancy member portion of the wall into an internal cavity defined by a molded expandable member portion of the wall; and sealing a slit remaining from the inverting.
• An anchoring frame deployment tool is provided that includes: a recess or cavity formed in a distal portion shaped and dimensioned to receive an anchoring frame therein; needles and a driving mechanism for driving the needles through the distal portion and the anchoring frame; wherein the needles have sufficient length to extend through an abdominal wall of a patient and out through the skin of the patient when the anchoring frame is contacted to an inner wall surface of the abdominal wall.
• An anchoring frame for anchoring a device to an internal structure in a patient's body is provided, including: a plurality of beams linked to be compressed into a narrow configuration and expanded to an expanded configuration; and a mechanical linking feature on each of at least two of the beams, the mechanical linking features configured to mechanically engage with mating features on the device.
• An assembly of mating engagement members for engaging an intra-abdominal, extra-gastric implant device with an anchoring frame is provided, wherein the assembly includes: a rail having a series of transversely placed openings along a length thereof; a channel configured to receive the rail and having at least one detent configured to pass through a wall of the rail through one of the openings; and an actuator for preventing the at least one detent from passing through the wall when in a first configuration; and allowing passage of the at least one detent through the wall when in a second configuration.
• These and other features of the invention will become apparent to those persons skilled in the art upon reading the details of the methods, devices, tools and assemblies as more fully described below.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 illustrates the anatomy of the abdominal cavity and its contents, and surrounding features.
• FIG. 2A is an illustration of a diaphragm in an isolated view, illustrating the conformation of the diaphragm as it exists in the body.
• FIG. 2B illustrates the diaphragm in position relative to the rib cage.
• FIGS. 3A and 3B show views of a main body of a device with a shape and size approximating the shape and size of a full (post-prandial) stomach.
• FIG. 4 illustrates (by arrows) potential locations on the stomach wall that can be displaced or compressed by one or more expandable devices as described herein.
• FIG. 5A shows an embodiment of a device having a buoyancy member contained in an internal chamber of an expandable member.
• FIGS. 5B-5C schematically illustrate alternative embodiments of buoyancy members.
• FIGS. 6A-6C illustrate a nested chamber configuration of a buoyancy member.
• FIG. 7 illustrates an embodiment of a device that includes a buoyancy member within an expandable member, where the buoyancy member is formed in the shape of an elongated spine.
• FIG. 8 illustrates an arrangement in which a self-expanding buoyancy member is provided within an expandable member of the device.
• FIG. 9 illustrates another arrangement of a device including a self-expanding buoyancy member.
• FIG. 10 shows a device having a buoyancy member that has inner and outer chambers.
• FIGS. 11A-11B illustrate devices that include a substantially rigid buoyancy member.
• FIG. 11C shows a buoyancy member having a substantially cylindrical shape.
• FIG. 11D illustrates a plurality of the shapes shown inFIG. 11C, joined by links to form a buoyancy member.
• FIGS. 12A-12B illustrate another example of a buoyancy member.
• FIG. 13 illustrates another arrangement of a buoyancy member within an expandable member of a device.
• FIG. 14 illustrates another arrangement of a buoyancy member within an expandable member of a device.
• FIG. 15 illustrates a device wherein a buoyancy member forms an internal spine in an expandable member.
• FIG. 16A illustrates an embodiment of a buoyancy member that is made of foam.
• FIG. 16B is a cross-sectional view of the buoyancy member ofFIG. 16A taken alongline16B-16B.
• FIG. 16C is a cross-sectional illustration of an alternative embodiment of a foam buoyancy member.
• FIG. 16D is a cross-sectional illustration of the buoyancy member ofFIG. 16C, after closing the internal chamber.
• FIG. 16E is a cross-sectional illustration of the buoyancy member ofFIG. 16b, after closing the internal chamber.
• FIG. 17 illustrates a mandrel that is shaped to conform to the opening in the buoyancy member shown inFIG. 16A.
• FIG. 18A-18K illustrate alternative configurations for forming structural type buoyancy members.
• FIGS. 19A-19B illustrate two different examples of molded buoyancy members that can be used as an internal spine.
• FIG. 20 illustrates a buoyancy member fixed to an inner surface of an expandable member.
• FIG. 21 shows an alternative embodiment of buoyancy member that is molded from foam.
• FIG. 22 illustrates an embodiment of a device having a buoyancy member attached to an inner wall surface of an expandable member to form an internal, buoyant spine.
• FIG. 23 illustrates a device having an elongated positioning loop attached thereto.
• FIG. 24 illustrates an exploded view of reinforcement tab and loop structures, demonstrating one method of bonding these structures to an expandable member.
• FIG. 25A illustrates a positioning tab bonded to a portion of an outer surface of an expandable member.
• FIG. 25B is a cross sectional view ofFIG. 25A taken alongline25B-25B.
• FIG. 25C shows a positioning tab that lies substantially flush with a surface of an expandable member.
• FIGS. 26A-26B illustrate an embodiment where tab(s) is/are extended to provide a shell-like rigidifying support of an expandable member.
• FIG. 26C illustrates a configuration where a reinforced frame structure or reinforcement backing layer extends superiorly of tabs.
• FIG. 27 shows an inferior portion of a device to illustrate an alternative arrangement for fixing or anchoring tab(s) to an internal abdominal structure.
• FIG. 28 schematically illustrates one suture having been tied down to anchor a portion of a tab to the inner surface of the abdominal wall.
• FIG. 29 shows a mold that is three dimensionally shaped to form an expandable member and a buoyancy member integrally as a single molded product.
• FIG. 30A illustrates the molded product after removing it from the mold shown inFIG. 29.
• FIG. 30B shows the molded product ofFIG. 30A pushing on the portion of the product that will form buoyancy member to invert it.
• FIG. 30C illustrates an open channel or slot after inverting the buoyancy member portion as shown inFIG. 30B.
• FIG. 31 illustrates an alternative mold in which a buoyancy portion is formed to extend superiorly of the superior portion of expandable member portion.
• FIGS. 32A-32E illustrate steps that may be carried out during a procedure for implanting an expandable extra-gastric device according to an embodiment of the present invention.
• FIG. 33F illustrates a sectional view of a patient (viewed from the feet of the patient) that shows the anchoring of an anchoring frame to the abdominal wall.
• FIG. 33G is a schematic illustration from a frontal view perspective, showing an anchoring frame anchored in place against the anterior abdominal wall.
• FIG. 33H illustrates advancement of a device, using a device deployment tool having already been preloaded with the device in a collapsed or compressed configuration over a guidewire.
• FIG. 33I shows a sectional illustration of a device having been locked into position on an anchoring frame.
• FIG. 33J shows trimming of conduit(s) to an appropriate length for connection with an adjustment member.
• FIG. 33K shows an adjustment member being anchored subcutaneously, to the external surface of the abdominal wall.
• FIG. 34 illustrates restriction of the stomach from expanding to its post-prandial, expanded configuration.
• FIGS. 35A-35D illustrate and instrument and method for anchoring an anchoring frame to an internal abdominal structure.
• FIG. 35E illustrates a patient's skin with needles protruding therethrough.
• FIG. 35F illustrates sutures extending from openings through the skin of the patient after removal of the needles shown inFIG. 35E.
• FIG. 35G illustrates one embodiment of a suture lock or clip installed over a suture.
• FIG. 35H illustrates a distal end portion or working end of a knot pusher tool being used to lock down a clip over a suture.
• FIG. 35I illustrates another embodiment of a knot pusher tool.
• FIG. 36A illustrates an alternative arrangement of needle and anchoring member that can be used for anchoring an anchoring frame.
• FIG. 36B illustrates an embodiment of a speed nut.
• FIG. 36C illustrates a plurality of ribbons having been anchored by fixing speed nuts against the external surface of the abdominal wall/fascia.
• FIGS. 36D-36E illustrate another embodiment of a speed nut that is configured to assume undeployed (or extended) and deployed (or compressed) configurations or states.
• FIGS. 36F-36G show side and perspective views of another embodiment of speed nut.
• FIG. 36H illustrates a ribbon having barbs, with barbs catching against the abdominal wall/fascia, thereby piercing into the abdominal walvfascia and flaring out radially somewhat.
• FIGS. 37A-37B illustrate an expandable anchoring frame.
• FIGS. 37C and 37D illustrate longitudinal sectional views of a portion of an arm or beam and ingrowth sheet, whereFIG. 37C shows a needle in a retracted configuration, andFIG. 37D shows the needle protruding through the arm or beam and ingrowth sheet.
• FIGS. 38A-38B illustrate mating engagement members that can be provided as part of any of the frames described herein and any of the expandable members described herein, respectively.
• FIG. 38C illustrates an expandable member in a compacted, low profile configuration for insertion into the abdominal cavity of a patient, with the central lumen of a rail having been threaded over a guidewire for sliding delivery and guidance of the device into the abdominal cavity.
• FIGS. 39A-39C illustrate another embodiment of mating engagement members.
• FIGS. 40A-40H illustrate various embodiments of buoyancy members that also function as anchoring frames.
• FIG. 41 shows examples of implant markers and sensors that may be included on a device.
• FIG. 42 illustrates a procedural step for anchoring an anchoring frame to an internal surface of an abdominal wall using ribbons.
• FIG. 43 illustrates a handheld device configured to communicate with one or more sensors located internally of a patient.
• FIG. 44 illustrates an example where a surface of an expandable member is provided with sensors comprising electrodes that can be used to deliver pacing signals to the stomach.
• FIG. 45 illustrates another embodiment of adevice10 configured to pace the stomach.
DETAILED DESCRIPTION OF THE INVENTION
• Before the present devices methods and instruments are described, it is to be understood that this invention is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.
• Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.
• Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.
• It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a conduit” includes a plurality of such conduits and reference to “the expandable member” includes reference to one or more expandable members and equivalents thereof known to those skilled in the art, and so forth.
• The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.
DEFINITIONS
• A “compliant” material refers to a material that is stretchable or expandable. This expansibility allows the material to increase in dimension substantially more than a noncompliant or semi-compliant material, prior to failure. For example, when formed as a balloon structure, a compliant material comprises an expansibility property of being able to increase its radius, beyond its formed radius, under pressure applied into the balloon, by 100 percent or more, without rupturing.
• A “noncompliant” material refers to a material that, when formed as a balloon structure, can increase its radius beyond its formed radius, under pressure applied into the balloon, only up to about 10 percent or less prior to rupturing.
• A “semi-compliant” material refers to a material that, when formed as a balloon structure, can increase its radius beyond its formed radius, under pressure applied into the balloon, by an amount between about 10 percent and about 100 percent, prior to rupturing.
• The “wall” of the stomach refers to all of the layers that make up the stomach wall, including the mucosa, submucosa, muscular layers and serosa. A “layer”, “layer of the stomach wall” or “stomach wall layer” refers to a mucosal layer, submucosal layer, muscular layer or serosal layer.
• A “proximal” end of an instrument is the end that is nearer the surgeon when the surgeon is using the instrument for its intended surgical application.
• A “distal” end of an instrument is the end that is further from the surgeon when the surgeon is using the instrument for its intended surgical application.
• An “internal body structure” when referred to as a structure to which a device is to be anchored, refers to a structure internal to the skin of a patient, and which can be within the abdominal cavity of the patient, or just outside of it, such as including the outer surface of a wall that partially defines the abdominal cavity. Structures to which a device can be anchored include, but are not limited to: one or more ribs, the intercostal muscles, the abdominal surface of the diaphragm, the stomach (but where the anchor does not pass through the wall of the stomach), the anterior abdominal wall, the posterior abdominal wall and the lateral abdominal wall, the esophagus, the angle of his in the stomach, the gastro-intestinal junction, the gastro-esophageal junction, the columnar ligaments of the diaphragm near the gastro-esophageal junction, the superior aspect of the omentum, peritoneum, liver, connective tissues, ligaments, and blood vessels.
• An “internal abdominal structure” refers to an internal body structure that is within the abdominal cavity of the patient, including the abdominal wall. For example, attachment to an inner wall surface of the abdominal wall is an attachment to an internal abdominal structure.
• The preferred embodiments of the present invention prevent the possible issue of erosion caused by an expandable member, by not requiring anchoring to the stomach, and further, by not requiring a substantial compression force to be applied when the stomach is not full of food. By allowing the stomach to move freely in the constrained spaced provided by the expandable member, the stomach's possible expansion size will be decreased, but there will be less opportunity for the formation of pressure necrosis since no one region will be subjected to concentrated forces. With the device in place, there is substantially no distensibility of the stomach as normal exists with an unconstrained stomach. With distensibility restricted and gastric volume reduced, as the patient ingests food, the intra-gastric pressure will rise to a level sufficient to produce satiety without distension or volume expansion of one or more regions of the stomach. The device occupies so much volume in the abdominal cavity that the stomach does not substantially depart from the shape set by the device even when filled with food. Another physiological benefit of the device is that the stomach's ability to relax in response to ingestion of food is reduced or eliminated, through producing earlier satiety. One additional physiological benefit of the expandable member may further be to substantially reduce the actual volume of the stomach itself, remodeling the organ as the muscle contracts into its new shape over the period of weeks or months (just as the heart remodels when constrained from over-expansion). Remodeling the stomach allows the expandable member to be implanted temporarily. The preferred embodiments also are positioned in a location to substantially fill the space normally occupied by the fundus, thus moving the stomach medially and wedging the stomach between the expandable member and the medial and anterior aspects of the liver, and the spine posteriorly. This position also ensures that the expandable member is almost entirely maintained underneath the diaphragmatic umbrella beneath the ribs on the left side, thus concealing the expandable member, and preventing it from producing an unsatisfactory cosmetic result. Further, the preferred embodiments can have elements for anchoring on one or more locations along the abdominal cavity wall to prevent migration. Further, the preferred embodiments are provided with an outer surface that is very atraumatic. Embodiments described may include at least one expandable member, preferably an inflatable member, made of a material or material composite that is impermeable to fluid, which may be substantially impermeable to gas and is at least impermeable to liquid, as well as embodiments having at least two expandable members, with one expandable member being inflated with a gas and another expandable member being inflated with a liquid. Other embodiments include an expandable member and a buoyancy member that may or may not be expandable, and which adds buoyancy to the device. For example, a buoyancy member may be included with a liquid-filled expandable member of a device, that by itself, has negative buoyancy, so that the buoyancy member provides positive buoyancy to bring the combined buoyancies of these components of the device nearer to a neutral buoyancy, when implanted into the abdominal cavity of a patient. It can be beneficial to make the combined buoyancy slightly positive in the abdominal cavity to help prevent the device from migrating down in the patient.
• The devices described herein can be provided as versatile devices. For example, the same device with an expandable member can be implanted and attached to either in a laparoscopic surgical procedure, an oral trans-gastric procedure, or a variation of percutaneous procedures in which non general anesthesia and little or no insufflation are used. The device can be implanted and anchored directly to at least one internal abdominal structure, or alternatively, can be implanted by fixing to an anchoring frame having been anchored to at least one internal abdominal structure.
Abdominal Cavity Anatomy
• FIG. 1 illustrates the anatomy of the abdominal cavity and its contents, and surrounding features. Theabdominal cavity100 is shown divided among four quadrants, the upperright quadrant102, upperleft quadrant104, lowerleft quadrant106 and lowerright quadrant108, as divided by themedian axis110 andtransverse axis112. The lower edge of the ribcage is illustrated by the dottedline114 and the diaphragm is shown at116. As seen inFIGS. 2A and 2B, thediaphragm116 is shaped like a parachute and sits within the ribs. Theesophagus118 passes through thediaphragm116 and joins with thestomach120. Theleft lobe122 of theliver121 lies anteriorly of theesophagus118 and the fundus-cardia junction119. In one aspect of the invention, an expandable device is implanted in an extra-gastric location (i.e., outside of the stomach) generally indicated at124, and then expanded to occupy a space that the fundus of the stomach would ordinarily expand into when the stomach is filled with food. The expanded device prevents this expansion by the fundus, thereby limiting the volume of the cavity in the stomach to a much smaller volume than if the fundus had been allowed to expand into the space. Alternatively, the device is expanded to apply pressure to the fundus of the stomach in a downward direction (e.g., in a direction toward thetransverse axis112 shown, with some transverse movement toward themedian axis110 shown), and optionally, additionally to the main body of the stomach, to reduce the volume inside the stomach to effect satiety in the patient with relatively less food ingested, relative to what the patient would require for satiety without the implant in place.
Devices
• At least some embodiments of devices described herein can be implanted percutaneously, with a relatively quick and simple procedure that requires no general anesthesia and wherein only a single, small opening in a patient is required to deliver the device, which typically has a single expandable member that is self anchoring or can be easily anchored to maintain the simplicity and minimal invasiveness of the procedure.
• In other embodiments, configurations of expandable members are provided, where a device can contain one or more expandable members and one or more steps of implantation and anchoring may be performed laparoscopically with remaining steps being performed percutaneously. Further alternatively, implantation and anchoring a device may be performed with most if not all steps being performed laparoscopically or orally through a trans-gastric procedure. Any of the devices described herein can, of course, be implanted using open surgical procedures. Devices that can be implanted percutaneously can alternatively be implanted using laparoscopic procedures.
• Devices described herein can be implanted permanently, but are also configured for reversibility, to facilitate relatively simple removal procedures, should it be desired to remove a device. Alternatively, devices according to the present invention can be implanted temporarily, such as over a period of months, and then removed or disabled when further treatment is no longer required, or to allow an alternative treatment to be applied.
Device Body Configurations
• FIGS. 3A and 3B show views of adevice10 having amain body10m,10emwith a shape and size approximating the shape and size of the full (post-prandial)stomach120. Althoughmain body10mneed not be expandable/collapsible to perform restriction of stomach expansion,main body10mis typically formed from one or moreexpandable members10emas will be described in further detail below, for better performance of intended functions and to allow less invasive procedures for implanting the same.
• Main body10m,10emincludes curved left andright sides101 and10r, respectively (FIG. 3A shows the posterior surface ofmain body10m,10em), wherein the left side10lis convex and theright side10ris concave such that themain body10m,10emtakes on the shape of a portion of the full stomach that expands from the shape of a substantially empty stomach. Thesuperior portion10sis substantially larger and more bulbous than theinferior portion10i, since the fundus portion of thestomach120 expands much more than the antrum upon receiving food. Thus, as seen in the right side view ofFIG. 3B, thesuperior portion10sis very bulbous and almost spherical, with a larger cross section than theinferior portion10i, while the inferior portion is more nearly hemispherical, with the center portion of the main body tapering from thesuperior portion10sto theinferior portion10i. Configured as such, themain body10m,10em, when implanted properly, will occupy the space that naturally exists from thestomach120 to expand into when expanding from a pre-prandial configuration to a post-prandial configuration. By severely limiting this expansion capability, the patient is thereby able to consume only a significantly smaller volume of food than possible if the implant were not present.
• Device10 sizes will likely vary depending on the size of the skeletal system of the patient into whichdevice10 is to be implanted, particularly the size of the rib cage. Further variations may be made to tweak or adjust the amount of restriction along any desired location of the stomach that interfaces withdevice10. One typical variation is in the length and/or size (diameter or expandability capacitance) of theinferior portion10i. In some embodiments, theinferior portion10iof theexpandable member10emmay be made longer than shown inFIGS. 3A-3B to extend further inferiorly and medially than the inferior portion of the expandable member shown inFIGS. 3A-3C.
• At least a portion ofmain body member10mmay be expandable. The entiremain body10mmay be made of anexpandable member10em. When in an expanded configuration,expandable member10emcan optionally only abut or lie adjacent to the pre-prandial stomach wall, without imparting any significant deformation forces thereto. However, when the patient eats and the stomach begins to fill,expandable member10emin this case prevents thestomach120 from expanding into the volume occupied byexpandable member10em. In such a case, thestomach120 becomes “deformed” as it attempts to expand and can only expand in a limited fashion, if at all, around a portion of the perimeter ofexpandable member10em. Thus, upon expanding thedevice10, thedevice10 expands in the space(s) normally occupied by thestomach120 as thestomach120 expands when receiving food. Thusdevice10 exerts pressure on, or at least prevents expansion of the fundus and optionally, the antrum. In embodiments where theexpandable device10 is not attached to the stomach, the stomach is free to perform its normal function of mixing food in the stomach for digesting and pushing food out of the stomach. During all of this movement the stomach may slip behind, beside or on top of the expandable device, but the internal volume of the stomach will be held to its smaller volume as theexpandable device10emis occupying the space into which the stomach would normally expand. Further details of methods for treatment of obesity, including procedures for implanting devices described herein are described below.
• As noted above, anexpandable device10 can be implanted adjacent a surface of the stomach wall, either in contact therewith or at a predetermined distance therefrom, to prevent expansion of thestomach120 into a volume occupied by theexpandable device10. Alternatively, some embodiments of the devices described herein can be configured and placed to exert an external compression on one or more locations of the stomach to deform the stomach wall, thereby decreasing the internal volume of the cavity within the stomach that accepts food and liquid intake.FIG. 4 illustrates (by arrows) potential locations on thestomach120 wall that can be compressed (or restricted from expanding) by one ormore devices10 as described herein.
• In one embodiment,expandable member10emshown inFIGS. 3A-3B is composed of aninflatable member10em. Inflatable members described herein can be inflated with gas or liquid or both. Examples of gases or liquids that can be used to inflate inflatable members/devices10 include, but are not limited to: carbon dioxide, helium, isotonic dextrose solution, iostonic saline solution, air.
• At least a portion of theexpandable member10emshown inFIGS. 3A-3B may be inflated with one or more gases, to provide a relatively lighter, less dense implanteddevice10, relative to an expandable member completely filled with liquid. The entireexpandable member10emmay be inflated with one or more gases. Alternatively, the entire expandable member103mmay be inflated with one or more liquids. Further alternatively,devices10 can be at least partially inflated with a porous gel that is porous or microporous to encapsulate air or other gas bubbles, thereby reducing the weight of the gel while still permitting it to apply volumetric pressure to expand an inflatable member. Such gels may be settable, such as ultra-violet (uv) curable or otherwise chemically curable, or, alternatively, can remain in the gel state, so that they can be readily removed or added to, to increase or decrease the amount of inflation/expansion of the expandable member. Gels can be made from a flowable viscoelastic substance made of a polymer mixture, such as silicone oil, boric acid, hyaluronic acid, polyacrylic acid or combinations thereof, for example. The gel, as delivered into theexpandable member10em(e.g., such as by injection or the like) can be aerated or infused with carbon dioxide or an inert gas to create a deformable or non-deformable cellular structure that encapsulates the gas in cells, and thus has relatively low mass but still has significant resistance to compression or deformation.
• When an expandable member is inflated solely with a pressurized gas, although this reduces the overall weight and density of thedevice10, it may tend to be overly buoyant when implanted in a patient. Because a patient is made up primarily of water, the air, carbon dioxide, or other pressurized gas in expandable member tends to be very buoyant relative to its surroundings in the abdominal cavity, which are primarily water. Depending upon the orientation of the patient's abdominal cavity at any particular time, the buoyancy of such adevice10 may establish a force that tends to drivedevice10 toward a location away from its intended, predefined location, and may cause thedevice10 to tend to migrate away from its intended location to a less desirable position. Also, in the case of adevice10 having multiple expandable members where one is gas filled and one is liquid filled, the buoyancy of the gas filled expandable member may cause it to pull away from a liquid filled expandable member, particularly if the liquid filled expandable member is anchored to an internal structure, and this may cause undesirable results such as unwanted separation of the expandable members and/or failure of one or more of the expandable members.
• Accordingly, it may be desirable to provide a device that has a density that is closely matched to the density of its surroundings when implanted in the abdominal cavity. Assuming that the abdominal cavity has a density of saline and is made entirely of saline, then anexpandable member10emfilled with saline would be substantially neutrally buoyant when implanted within the abdominal cavity and would not exert any positive or negative buoyancy forces when implanted therein. At the other end of the spectrum, if the abdominal cavity were completely filled with fat, then a device having anexpandable member10eminflated with an oil matching the density of the fat could be implanted so as not to create any negative or positive buoyancy forces when implanted in the abdominal cavity. In reality, a typical abdominal cavity of a patient will include both water(saline) and fat, with relative amounts (percentages) of fat varying from patient to patient. Accordingly,device10 can be designed to have a density somewhere in between the density of saline and that of fat, with the amount of buoyancy being relatively greater for those abdominal cavities having relatively more fat that those having relatively less fat.
• FIG. 5A shows an embodiment ofdevice10 having abuoyancy member10bmcontained in the internal chamber ofexpandable member10em. For example,buoyancy member10bmmay be formed of a substantially gas impermeable material and can be inflated with air, CO₂, or other inert gas to reduce the overall density ofdevice10 in the expanded configuration shown inFIG. 5A.Expandable member10emcan be filled with a liquid, such as saline, dextrose solution, or other biocompatible liquid, for example, and this liquid interfaces with the external surface ofbuoyancy member10bmin the expanded configuration shown.Buoyancy member10bmcan be shaped such that a superior portion thereof has a curvature that substantially matches the curvature of the superior end portion ofexpandable member10em, such as shown inFIG. 5A, to that when inflated and whendevice10 is implanted in the patient in the intended orientation and the patient is upright,buoyancy member10bmfloats to the superior end portion ofexpandable member10emand fits in the apex of the superior portion to helpsecure buoyancy member10bmat this location and minimize movement. The position ofbuoyancy member10bmwithinexpandable member10emorientsexpandable member10emsuch that the superior end ofexpandable member10emis against or near the undersurface of the umbrella-shapeddiaphragm116, due to the buoyant effect ofbuoyancy member10bmonexpandable member10em. Alternatively,buoyancy member10bmmay be fixed to the inner surface ofexpandable member10em, by adhesives, orbuoyancy member10bmcan be co-molded withexpandable member10em.Buoyancy member10bmcan be fixed in the position shown inFIG. 5A in at least one embodiment.
• Aconduit12₁can be provided in fluid communication withbuoyancy member10bmas shown inFIG. 5A, which has a length to allow a proximal end portion thereof to extend out of the body of the patient whendevice10 is implanted in the desired location and orientation in the abdominal cavity of a patient and expanded. Aconduit12₂can also be provided in fluid communication withexpandable member10em, and this conduit also has a length to allow a proximal end portion thereof to extend out of the body of the patient whendevice10 is implanted in the desired location and orientation in the abdominal cavity of a patient and expanded. As shown,conduits12₁and12₂are integrated into asingle tube12 having twolumens12₁and12₂until the location whereconduit12₂splits off to feed intoexpandable member10emasconduit12₁continues on to join in fluid communication withbuoyancy member10bmafter passing through the wall ofexpandable member10em. The wall ofconduit12₁is sealed withexpandable member10emto maintainexpandable member10emat least liquid impervious (and may optionally be substantially gas impervious). Likewise,conduit12₁is substantially gas impervious and joins in a sealed connection withbuoyancy member10bmto maintain it as a substantially gas impervious chamber.Conduit12₂is at least substantially liquid impervious joins in a sealed connection withexpandable member10emto maintain it as a substantially liquid impervious chamber, optionally as a substantially gas impervious chamber.Conduit12₁may run along the surface ofexpandable member10emas shown and may be free of the surface ofexpandable member10emexcept for where it inserts through the wall ofexpandable member10em. Alternatively,conduit12₁may be fixed at one or more locations along its length that is adjacent toexpandable member10em, or the entire adjacent length may be fixed to the surface ofexpandable member10em, such as by adhesive, taping, or other mechanical fixation.
• Further alternatively,conduit12₁may extend inside ofexpandable member10em, as illustrated in phantom lines inFIG. 5A. In this case, conduit12₁(as well as conduit12₂) may connect withexpandable member10emat an inferior location, such as one that is closest to an opening though whichdevice10 is inserted during implantation, for example. Further alternatively,conduits12₁and12₂may be provided as completely separate conduits along the full lengths thereof.
• In one particular embodiment,expandable member10emis formed of silicone andbuoyancy member10bmis formed of silicone. However, buoyancy member may include at least one layer, or may be coated with a material that reduces the permeability ofbuoyancy member10bmto gas whenbuoyancy member10bmis in the expanded configuration shown inFIG. 5A. For example, buoyancy member may include a metallic layer or coating, such as titanium, silver, or other relatively inert, biocompatible metal. Alternatively, asilicone buoyancy member10bmcan be coated with parylene to appreciably reduce gas permeability of thebuoyancy member10bm. As another alternative,buoyancy member10bmmay be formed by co-extrusion, e.g., co-extruding EVOH (ethylene-vinyl alcohol copolymer) and polyurethane to form thebuoyancy member10bm, with or without a metallic coating as described above. As another alternative embodiment,buoyancy member10bmmay be formed of a blend of silicone and polyurethane. Further alternatively, thebuoyancy member10bmcan be formed from or include one or more semi-compliant or non-compliant materials. Examples of useable semi-compliant materials include, but are not limited to: nylon, polyethylene, polyester, polyamide and polyurethane, see for example, U.S. Pat. No. 6,500,148, which is hereby incorporated herein, in its entirety, by reference thereto. Polyurethane, nylon, polyethylene and polyester can be compliant or semi-compliant materials, depending upon the specific formulation and hardness or durometer of the material as produced. Examples of noncompliant materials that can be used in the construction of inflatable members described herein include, but are not limited to: polyethylene terepthalate (PET) and urethane.Expandable member10emcan optionally be formed in any of the manners described above with regard tobuoyancy member10bm.
• FIGS. 5B-5C schematically illustrate alternative embodiments ofbuoyancy members10bm, wherein inFIG. 5B,buoyancy member10bmcomprises a ring of gas-filled beads, and inFIG. 5C,buoyancy member10bmcomprises a gas-filled coil.
• As shown inFIG. 5A, buoyancy member, although it may be variably expandable in volume in an expanded configuration, particularly when it is formed of a compliant material, is still somewhat predetermined as to its volume, within a given range, as it will typically be inflated to a predetermined pressure that has been calculated to not stretch the walls of the buoyancy member to a point where they are unacceptably porous to gas leakage. Optionally, abuoyancy member10bmmay be provided that is more adjustable in the volume that it can contain, giving the user the ability to adjust the buoyancy member over a larger range of volumes so as to adjust the overall buoyancy/density ofdevice10 in the expanded configuration.FIGS. 6A-6C illustrate one version of an adjustablevolume buoyancy member10bmthat is provided with a “nested chamber” configuration, in which chambers10c1-10c4 (although different numbers of chambers can be provided, which number may be two, three, or more than four) can be sequentially expanded, to vary the size of thebuoyancy member10bmand thus the volume of gas and amount of buoyancy added to theoverall device10 that buoyancy member forms a part of. Adjacent chambers can be separated by a baffle ormembrane36 that may be formed of the same material as the wall ofbuoyancy member10bm, for example, with each baffle ormembrane36 containing at least one one-way valve38 therein.Valves38 are configured to open at progressively greater pressures, so that the chambers can be opened sequentially and only to the extent desired, based on the amount of pressure applied throughconduit12.
• FIG. 7 illustrates an embodiment ofdevice10 that includes abuoyancy member10bmwithinexpandable member10emwherebuoyancy member10bmis formed in the shape of an elongated spine. In this particular embodiment,buoyancy member10bmis an elongated tubular member having a curvature that generally corresponds to the curvature ofexpandable member10emin the expanded configuration, to follow the contour thereof. Alternatively,buoyancy member10bmcould be formed as a straight tubular member. In either conformation, the length dimension of buoyancy member is such to extend over at least half the length ofexpandable member10emor at least two thirds of the length ofexpandable member10emor at least three quarters of the length ofexpandable member10em. In either the straight or the curve conformation, the length of buoyancy member distributes the buoyancy more equally over the volume of the expanded expandable member, compared to abuoyancy member10bmthat is allowed to float to one particular location of an expandable member. The embodiment having a curvature that somewhat conforms to the curvature of the expandedexpandable member10emhas been found to distribute the buoyant forces even better than a buoyancy member having a straight conformation. This distribution of the buoyancy forces helps to maintain the expandedexpandable member10emin the desired location, as well as orientation that it is implanted in, as it minimizes any torquing forces or other uneven forces that a less well distributed buoyancy member may place on the expanded expandable member. In this embodiment, like all other embodiments described herein,buoyancy member10bmcan be sized to provide an amount of buoyancy that, when combined withexpandable member10em, provides a substantially neutral buoyancy when implanted in the abdominal cavity of the patient. Neutral buoyancy refers todevice10 having a density about the same as the density of the surrounding environment in the abdominal cavity in which the device is implanted. Accordingly,device10 will thus not tend to either sink or float in the abdominal cavity, but have a tendency to remain substantially in the location implanted.
• Alternatively, this embodiment, or any other embodiment described herein, may be configured to have a slightly positive buoyancy. This slight (e.g., less than 0.2 pounds positive buoyancy when implanted, typically much less than 0.2 pounds but greater than zero pounds) buoyancy tends to right the device in a situation where the positive buoyancy is applied in a superior portion of the expandable member and the patient is in an upright sitting or standing position, for example. An alternative technique for adding buoyancy, such as to adjust a displaced device, or that can even be utilized at the original implantation of the device, is to input a small quantity of gas into the liquid filledexpandable member10em. This can be done at the time that theexpandable member10emis filled with liquid, or, for example, on a subsequent patient visit. When done subsequently, the physician may optionally withdraw a small amount of liquid to provide space to be occupied by the small gas volume.
• Accordingly, depending on the relative volumes and densities ofexpandable member10emandbuoyancy member10bm,device10 can: 1) reduce the overall density to reduce the relative “weight” of the implant within the abdomen (i.e., a neutrally buoyant implant will neither sink nor float but maintain a relatively stable position relative to the surroundings in the abdominal cavity); 2) achieve neutral buoyancy within the abdomen; or 3) achieve a slightly positive buoyancy that helps orient thedevice10 upwards into a desired position and orientation (e.g., located against the fundus and the diaphragm).
• In one particular embodiment, thebuoyancy member10bmofFIG. 7 is an inflatable tube that can be inflated with gas to provide buoyancy. In one particular embodiment, buoyancy member is a silicone tube that is inflatable with about five to about twenty cc volume of gas. In one specific embodiment,buoyancy member10bmwas inflated with ten cc air.Buoyancy member10bmmay be left free floating withinexpandable member10emor may be fixed to an inner wall ofexpandable member10em. Further alternatively,buoyancy member10bmmay be co-molded withexpandable member10em. Whenbuoyancy member10bmis not allowed to free float, but is fixed in some manner relative toexpandable member10em, this may reduce the risk of failure due to wear that might possibly be caused by repetitive contact betweenbuoyancy member10bmandexpandable member10emwhenbuoyancy member10bmis allowed to free float.Buoyancy member10bmmay be pre-inflated prior to insertion through the body of the patient, or even prior to assembly within the expandable member. Alternatively, a conduit12₁(shown in phantom lines inFIG. 7) may be provided in fluid communication withbuoyancy member10bmso that buoyancy member can be inflated afterdevice10 is inserted into the patient, either before or after inflation ofexpandable member10em.
• FIG. 8 illustrates an arrangement in which a self-expandingbuoyancy member10bmis provided withinexpandable member10emofdevice10. Self-expandingbuoyancy member10bmcan be formed of silicone, or other biocompatible elastomer, for example, and can be molded in the expanded configuration shown inFIG. 8, with an openinferior end10bmo. Sincebuoyancy member10bmhas an internal chamber or space, the buoyancy member can be compressed or flattened to a much reduced configuration, with a much smaller cross-sectional dimension to facilitate insertion though a small opening in the patient for percutaneous delivery.Buoyancy member10bmhas walls of sufficient thickness and elasticity that when compressive forces are withdrawn,buoyancy member10bmautomatically returns to the expanded configuration shown inFIG. 8 without the need to input pressurized gas or liquid into the chamber, as the walls elastically return to the expanded configuration that they were formed in. This elastic driving force also draws air (or any fluid medium that opening10bmois in fluid communication with at the time of the expansion of the walls) into the chamber ofbuoyancy member10bm.
• Accordingly, buoyancy member can be compressed to its compressed configuration andexpandable member10emcan be compressed aroundbuoyancy member10bmwhereexpandable member10emis also in a compressed, non-expanded configuration, so thatdevice10 is reduced significantly in cross-sectional dimension for insertion into a patient. For example,device10 in the compressed configuration may resemble a cylinder. After passingdevice10 through a small opening in the patient and into the abdominal cavity (such as through a sheath, for example, or by manually inserting thedevice10, while maintaining compression on the device as it is being stuffed through the small opening)conduit12 that is in fluid communication withexpandable member10emhas a proximal end portion that remains extending out of the patient. Also, a removable conduit12₁(shown in phantom lines inFIG. 8) is in fluid communication with, and seals off theopening10bmoofbuoyancy member10bm. A proximal end portion ofconduit12₁also remains outside of the patient whendevice10 has been inserted into the abdominal cavity and placed in a desired location and orientation for implantation. However, the proximal end ofconduit12₁need not be connected to a pressurized source of gas (although it can be), but can simply be open to the atmosphere (with or without a filter). Thus, when the compressive forces are removed fromdevice10,buoyancy member10bmself-expands, thereby drawing gas throughconduit12₁which fills the inner chamber ofbuoyancy member10bm.Conduit12₁can then be detached frombuoyancy member10bmand withdrawn fromexpandable member10emand from the body of the patient. A one-way valve10emvis provided in the wall ofexpandable member10emto seal off the opening through whichconduit12₁is removed. Optionally, a one-way valve10bmvmay be provided in the open end ofbuoyancy member10bmto prevent gas from migrating intoexpandable member10em. Further optionally, theopen end10bmoandvalve10emvcan be integrated at the wall ofexpandable member10em.Buoyancy member10bmmay be free floating or fixed according to any of the techniques described above. In one particular embodiment, buoyancy member is bulb-shaped, like the shape of a bulb on a turkey baster, with the bulb portion oriented toward the superior end portion ofexpandable member10em.
• FIG. 9 illustrates another arrangement of adevice10 including a self-expandingbuoyancy member10bm. In thisexample buoyancy member10bmis a spherical member that operates in any of the same manners described above with regard to the embodiment ofFIG. 8. Thedevice10 shown inFIG. 10 has abuoyancy member10bmthat has inner andouter chambers10bm1 and10bm2, respectively. After insertion ofdevice10 into the abdominal cavity,internal chamber10bm1 can be allowed to self-expand or, alternatively, pressurized gas may be inputted to expand the inner chamber. In either case, gas is inputted throughremovable conduit12₁. In either case,inner chamber10bm1 is provided with a one-way valve10bmvto close off opening10bmoafter removal ofconduit12₁to prevent loss of gas to theexternal chamber10bm2.Conduit12₂is used to deliver pressurized fluid (e.g., pressurized saline or the like) toexternal chamber10bm2 and thenconduit12₂can be removed. All openings indevice10 thatconduits12₁and12₂pass through are closed off by oneway valves10bmv,10emvwhenconduits12₁,12₂are removed. Alternatively, the conduits and valves can be maintained so that the gas pressure withinbuoyancy member10bmcan be adjusted at a later time. The pressurized liquid inexternal chamber10bm2 helps to maintain the gas withininternal chamber10bm1 and prevent it from migrating out into pressurizedchamber10bm2. This is achieved because the pressure withinbuoyancy member10bm2 creates a “structural shell” aroundbuoyancy member10bm1. As thisshell10bm2 is pressurized and takes form, the gas is inputted throughconduit12₁into the cavity (inner chamber) ofbuoyancy member10bm1 so that there is not a vacuum in the inner chamber, thereby helping preventshell10bm2 from collapsing. Cooperatively,buoyancy member10bm2, once pressurized, hold open the cavity/inner chamber ofbuoyancy member10bm1. Depending on the material properties ofbuoyancy member10bm2, gas may be able to permeate out of the cavity ofbuoyancy member10bm1. However, because of the structure ofbuoyancy member10bm2, the gas will not permeate out to an extent that would create a negative pressure, since energy would have to be expended to force the gas out and create a negative pressure.Expandable member10emcan be expanded by inputting pressurized liquid throughconduit12.
• In general, fordevices10 described herein, the pressure withinexpandable member10emwill vary depending upon the material used to form the wall of theexpandable member10em, as well as the geometry of theexpandable member10em, and whether gas or liquid is used to inflate theexpandable member10em. For example, anexpandable member10emmade of silicone that is inflated with saline typically has an internal pressure ranging from about 0.25 pounds per square inch (psi) to about 1.0 psi, depending upon the degree of inflation. Because saline is relatively incompressible,expandable member10emwill hold its volume under the pressures of the abdomen. Alternatively, ifexpandable member10emis filled with a gas, the pressure may be increased to ensure that the abdominal pressures do not compress the shape ofexpandable member10em, thereby deforming it. The means pressures in the abdomen typically range between about 0 psi to about 0.4 psi. If a person is jumping or coughing, abdominal pressures may spike as high as about 4.0 psi. Thebuoyancy member10bmneeds to be designed to that its shape can withstand the sum of the pressure ofexpandable member10emand the at least the mean abdominal pressure (or, preferably, peak abdominal pressure). This can be achieved by designingbuoyancy member10bmto have sufficient structural strength to withstand the sum of these pressures. One approach in such design is to providebuoyancy member10bmwith a hard plastic shell that is structurally strong enough to withstand about 5 psi compression forces. Another approach is to designbuoyancy member10bmas flexible membrane that self expands via a compressible foam. In this case, the foam, upon expanding the flexible membrane ofbuoyancy member10bm, draws air into a chamber defined by the flexible membrane as the foam expands into it. In this type of design, the structure ofbuoyancy member10bmneeds to withstand the means pressures (e.g., about 2 psi) and, during pressure spikes,buoyancy member10bmmay deform and rebound after expiration of the spike, due to the elastic properties of the foam. Further alternatively,buoyancy member10bmmay be inflated with a gas. In this arrangement, the gas withinbuoyancy member10bmneeds to be able to maintain a pressure to withstand the peak sums of pressures withinexpandable member10emand the abdomen, for example, about 5 psi.
• FIGS. 11A-11B illustratedevices10 that include a substantiallyrigid buoyancy member10bm. For example, inFIG. 11A,buoyancy member10bmis a hollow, substantially rigid sphere, somewhat like a ping pong ball. As long as the outside diameter ofbuoyancy member10bmis less than or possibly slightly greater than (since tissue is stretchable) a cross sectional dimension of an opening in the patient thatdevice10 is delivered through, then the buoyancy member does not need to be compressible. For example, the outside diameter of buoyancy member may be less than about 50 mm. For example,buoyancy member10bmmay be made from polyethylene, or other relatively low density, biocompatible polymer or even thin-walled biocompatible metal.Buoyancy member10bmmay be free floating withinexpandable member10emor fixed to an inner wall surface ofexpandable member10emaccording to any of the techniques described above. To increase the buoyancy effect, additional balls or other substantially rigid buoyancy structures may be added, since the overall size of thesingle buoyancy member10bmcannot be substantially increased in this case, for reasons noted above.FIG. 11B shows adevice10 that includes abuoyancy member10bmhaving four substantiallyrigid buoyancy members10bm1-10bm4, which are spherical in this case, although different shapes may be used, as noted. Thebuoyancy members10bm1-10bm4 are linked in the example shown inFIG. 11B by linkingmembers11, which may be polymeric or metallic strands, wires or threads, for example. The chain thus forming thebuoyancy member10bmmay be free floating as a chain, or fixed relative to theexpandable member10emin any of the ways described previously. Alternatively,buoyancy members10bm1-10bm4 may be left separate from one another and may be free floating, or these separate members may be individually fixed relative toexpandable member10emaccording to any of the previously described techniques.
• It is further noted that none of the alternative arrangements described with regard toFIGS. 11A-11B are limited to either use of either one or fourbuoyancy members10bm, as two, three or any number greater than four can be used to vary the relative buoyancy, up to a maximum number that would substantially completely fillexpandable member10emin the expanded configuration. Even with the completely filled arrangement, liquid can still be inputted intoexpandable member10emto fill the interstices betweenbuoyancy members10bm1-10bmN (where N equals the total number of buoyancy members used). In cases where the number ofbuoyancy members10bmused is greater than a maximum number that can be aligned in a single row so thatexpandable member10emcan be compressed therearound to form a substantially cylindrical shape for delivery through a percutaneous opening, the additional number of thebuoyancy members10bmover and above that maximum number (or alternatively, allbuoyancy members10bm) may need to be loaded into expandable member after inserting the expandable member (with or without a portion of the buoyancy members already loaded therein) into the abdominal cavity. In such case,expandable member10emcan be provided with a valve or otherwiseclosable opening10emohaving a sufficient diameter to allowbuoyancy members10bmto be inserted therethrough. After inserting buoyancy members through the incision in the patient (which may include insertion through a sheath or cannula) and intoexpandable member10em, expandable member can be sealed to provide a liquid impermeable chamber.
• It is further noted that the shape ofbuoyancy member10bmshown inFIG. 11A does not have to be spherical, but can be any other shape that includes a sealed off, gas-containing chamber therein and which has a maximum cross-sectional dimension that does not exceed a predetermined maximum dimension (examples of which were described above) that would prevent it from being inserted (withdevice10 compressed therearound) through a small opening in a patient for delivery into the abdominal cavity.FIG. 11C shows one alternative shape in which buoyancy member has a substantially cylindrical shape, with a central cavity that seals gas therein.FIG. 11D illustrates a plurality of the shapes shown inFIG. 11C (i.e.,10bm1,10bm2 and10bm3) joined bylinks11 to formbuoyancy member10bm. Alternatively, these buoyancy members do not have to be shells, but can be solid and made of a material with very low density, e.g., a foam, sponge or rigid plastic with many air pockets. Substantially rigid plastics can be altered to lower their densities by infusing them with air bubbles or pockets during their manufacture. Another technology uses micro-hollow glass spheres to reduce the density of a plastic when infused therein during manufacture. Another alternative provides a large number of small plastic hollow spheres encapsulated within a larger shape. For example, a thin walled silicone member can contain a larger number of small polyethylene hollow spheres, to provide abuoyancy member10bmhaving an overall shape of the silicone member, with thebuoyancy member10bmhaving a density substantially less than that of saline.
• FIGS. 12A-12B illustrate another example of abuoyancy member10bm. In this embodiment, atubular member10bmtis provided that has an annulus therethrough of inside diameter that permits substantiallyrigid buoyancy members10bm1,10bm2, . . . ,10bmN (where N=the total number of buoyancy members) to be loaded therein. For example,tubular member10bmtmay be flexible, and may even be expansible so as to stretch somewhat as it is deformed bybuoyancy members10bmbeing inserted therein, when buoyancy members have a slightly greater cross-sectional dimension that the inside diameter of the annulus oftubular member10bmt. Alternatively, buoyancy members may be freely slidable into the annulus without deformation oftubular member10bmt, and in this case, tubular member can be flexible or rigid. In one particular embodiment, tubular member is formed from silicone, either from a sheet, or extruded in the tubular shape. In another particular embodiment, tubular member includes layers of EVOH, low density polyethylene, and polyurethane to provide an even better gas impermeable barrier.Buoyancy members10bm1, etc. can be formed the same as described above with regard toFIGS. 11A-11B.
• Once the total number of buoyancy members desired have been loaded intotubular member10bmt, the ends oftubular member10bmtare sealed off, as illustrated in the completedbuoyancy member10bmshown inFIG. 12B. The spaces in the annulus between thebuoyancy members10bm1, . . . ,10bmN can also hold gas and add to the buoyancy forces generated bybuoyancy member10bm. Thebuoyancy member10bmshown inFIG. 12B can be manufactured intoexpandable member10em, or can be inserted through an opening such as opening10emo, either before or after insertion ofexpandable member10emthrough an opening in a patient and into the abdominal cavity.Buoyancy member10bmmay be left free floating in the fluid used to expandexpandable member10emor may be fixed toexpandable member10emaccording to any of the techniques described previously. When tubularmember10bmtis flexible, it can be bent to follow the contour of an inside wall surface ofexpandable member10emin the expanded configuration, and fixed to the inside wall surface in that bent configuration.
• FIG. 13 illustrates another arrangement of abuoyancy member10bmwithin anexpandable member10emofdevice10. In thisarrangement buoyancy member10bmincludes a substantiallyrigid portion10bmrand anexpandable portion10bme. Substantiallyrigid portion10bmrshould not have any cross-sectional dimension that is substantially greater than a corresponding cross-sectional dimension of a small opening (such as a small incision, percutaneous opening, or port, for example) thatdevice10 is to be delivered through during placement into the abdominal cavity. As noted, such dimension may be slightly greater, since the skin and tissues of the patient can be stretched somewhat. In the example shown inFIG. 13, substantially rigid portion is tubular in shape with open ends and may have an outside diameter of one of the specifications noted above with regard toFIGS. 11A-11B. Alternatively, the substantially rigid portion can have an outside diameter that, when in inserted in acompacted device10, allows it to be inserted through an incision no greater than about seven cm, or no greater than about five cm. For example, substantially rigid portion may have a diameter no greater than about 2.00″, or no greater than about 1.85″, or no greater than about 1.5″. In this way,expandable portion10bmeandexpandable member10emcan be compressed down around the substantiallyrigid portion10bmrfor delivery through a small opening in a patient. Alternatively, theportion10bmrcan be semi-compressible such that it can also be compacted during insertion. However, it can still have enough structural properties to spring open on its own and thereby provide supportive structure to open the surroundingportion10bme. This compressibility ofportion10bmrallows it to be designed larger that the embodiment employing arigid portion10bmr, or, alternatively, allows a smaller incision in the patient required to insert thebuoyancy member10bm/device10.
• Upon placement ofdevice10 in a desired location in the abdominal cavity,expandable portion10bmecan be expanded with a pressurized gas source viaconduit12₁. Alternatively, the conduit can simply allow air intoexpandable portion10bmeasportion10bmrsprings open and expandsportion10bme, such that a source of pressurized gas would not be required to inflate thebuoyancy member10bmin this embodiment. It is noted thatconduit12₁can be a permanently placed conduit or it may be configured to be removable after inflatingexpandable portion10bme, wherein it (andexpandable portion10bmeas well asexpandable member10em) can be configured in any of the manners described in previous embodiments having removable conduits.Expandable member10emcan be inflated with liquid, such as saline or the like, viaconduit12₂.
• This arrangement should not require periodic refills of gas intobuoyancy member10bmor should at least reduce the frequency with which gas refills are necessary, since substantiallyrigid portion10bmrmaintains the volume of its shape, thereby maintaining at least a predetermined minimum volume of gas within thebuoyancy member10bm. Accordingly, even if there is some gas leakage out ofexpandable portion10bme,expandable portion10bmewill never shrink down to a size less than the volume occupied by substantiallyrigid portion10bmr, since substantiallyrigid portion10bmris sufficiently rigid to withstand deformation forces that can be provided thereagainst byexpandable portion10bmeand/or the liquid pressure of the liquid withinexpandable member10em.Buoyancy member10bmmay be free-floating, as illustrated, or may be fixed at one or more locations toexpandable member10emaccording to any of the techniques described previously. Also, the shapes ofexpandable portion10bmeand substantiallyrigid portion10bmrare not limited to those shown, but may vary. As one non-limiting example,expandable portion10bmemay be substantially cylindrical to follow the contours of a tubular substantiallyrigid portion10bmr.
• FIG. 14 illustrates another arrangement of abuoyancy member10bmwithin anexpandable member10emofdevice10. In this embodiment,buoyancy member10bmis made of foam or other structural arrangement that encapsulates small gas pockets and therefore does not have to be inflated after placement ofdevice10 in the abdominal cavity. Although shown as a flexible cylindrical structure,buoyancy member10bmcan be any other shape that lends itself to being inserted through a small opening in a patient whenexpandable member10emis compressed around it. A tubular or cylindrical shape particularly well lends itself to this task, as thedevice10 takes on a somewhat cylindrical shape in the compressed state where a distal end portion can first be inserted through the opening of the patient with the rest of the cylindrical body being pushed through in a direction along the longitudinal axis of the cylindrical shape. Additionally, a tubular shape allows a central annulus to be closed off to capture and maintain air in the chamber formed by closing the tube off at both ends.
• The foam used to make buoyancy member may be a silicone foam, or made from polyethylene or other biocompatible polymer for example. In each case, the foam is a closed-cell foam having a skin, so that the cells of the foam are closed and encapsulate air or other biocompatible gas therein, to ensure that the buoyancy properties of the foam are maintained and thebuoyancy member10bmcan therefore hold open a volume of gas and displace the liquid inexpandable member10em. It should be noted that some manufacturers denote a “sponge” as a closed-cell material, and other denote a closed-cell material as a “foam”. Alternatively, an open-cell material may be used, when a layer of encapsulation is established around this open-cell sponge or foam. The encapsulation layer may be dip-molded onto the open-cell structure, or can be manufactured separately and then assembled around the open-cell structure. Such a configuration utilizes the open-cell foam or sponge to provide structural support to hold open the encapsulation layer. The encapsulation layer provides a barrier between the gas contained within the open-cell foam/sponge and the saline or other liquid contained in theexpandable member10emoutside of thebuoyancy member10bm. An encapsulation layer may be provided over a closed-cell foam/sponge using any of the same techniques described above. Various different structural arrangements and shapes of foam as well as sponge-like structural arrangements that can be used to makebuoyancy member10bmare discussed in more detail below.Buoyancy member10bmmay be free-floating, as illustrated inFIG. 14, or may be fixed toexpandable member10emat one or more locations according to any of the techniques described with regard to previous embodiments above.Buoyancy member10bmhas a maximum outside dimension (e.g., outside diameter, or other cross-sectional dimension) that permits it, together with device compressed down around it, to be inserted through a small incision in a patient. Examples of such maximum outside dimension are those described above with regard to the maximum outside diameter ofrigid portion10bmrinFIG. 13.
• In one particular embodiment, the foam is a silicone foam made from silicone typically made to make a silicone sheet, but with a foaming agent (sodium bicarbonate, about 1% to about 5% by weight, typically about 5%) mixed with the silicone to make a slurry. This slurry can be described as having a consistency like peanut butter and the slurry is packed into a mold and then heated at about 150° C. for about an eighty minute cycle. The foaming agent, during the heat cycle, converts to water vapor, carbon dioxide and ammonia, thereby ensuring the biocompatibility of the resulting foam product. The mold is then removed from the heat and allowed to cool. After cooling, the foam product is removed from the mold and finished by removing any flash that may have formed. The finished product is a closed-cell foam that includes a skin layer both inside and outside. In another embodiment, the foam is polyethylene, which is expanded via high pressure carbon dioxide. The infusion of the carbon dioxide creates air pockets that form the foam, leaving a material that remains polyethylene which is therefore biocompatible.
• FIG. 15 illustrates adevice10 whereinbuoyancy member10bmforms an internal spine inexpandable member10emand distributes the buoyancy forces by being shaped proportionally to the expanded shape ofexpandable member10em. For example, inFIG. 15, expandable member is substantially eggplant shaped when in the expanded configuration shown. Likewise,buoyancy member10bmis also substantially eggplant-shaped, and is fixed toexpandable member10emto generally follow the contours of theexpandable member10emin the expanded configuration. This arrangement substantially distributes the buoyancy forces in a weighted distribution pattern that matches the weight distribution of the liquid in theexpandable member10emwhen it is expanded. Accordingly, the buoyancy forces are distributed as stably as possible, to minimize any torquing or other uneven forces thatbuoyancy member10bmmight otherwise apply todevice10 when implanted.
• Buoyancy member10bmis typically fixed toexpandable member10emalong the entire length ofbuoyancy member10bm. In the example shown,buoyancy member10bmis fixed to an internal surface ofexpandable member10em.Buoyancy member10bmmay be made of any of the foams described above with regard toFIG. 14, and may have acentral space10bmithat runs along the length thereof such that, when joined toexpandable member10em, the inner wall surface ofexpandable member10emand the walls ofbuoyancy member10bmseal off the internal space to maintain a gas-filled chamber therein.Buoyancy member10bmhas a maximum outside dimension (e.g., outside diameter, or other cross-sectional dimension) that permits it, together with device compressed down around it, to be inserted through a small incision in a patient. Examples of such maximum outside dimension are those described above with regard to the maximum outside diameter ofrigid portion10bmrinFIG. 13. Alternatively, the foam shape ofbuoyancy member10bmmay be compressed such that substantially all of the air insidecavity10bmiis expelled. Thecompressed buoyancy member10bmthen allows theentire device10 to be compressed down further, overall. This allows for either a larger outside diameter (expanded)buoyancy member10bmto be used, or a smaller incision length. After insertion ofdevice10 into the abdominal cavity, the foam can then be allowed to spring open by allowing air or pressurized gas to flow intochamber10bmi, for example, via aconduit12. Theconduit12 may have a one-way entry and may be removable, in a manner as described previously.
• FIG. 16A illustrates an embodiment of abuoyancy member10bmthat is made of foam can be joined toexpandable member10emas an internal spine member in a manner as described above with regard toFIG. 15. Since the foam is less dense than the material making up the wall ofexpandable member10em, its walls can be made substantially thicker than theexpandable member10emwall, thereby providing some structural rigidity as an internal spine, and, at the same time, encapsulating more gas to improve the buoyancy function.Buoyancy member10bmcan be formed with a hollow core that is open, when molded, and will be closed whenbuoyancy member10bmis fixed toexpandable member10emto seal thespace10bmi. Accordingly, the surfaces or edges of thewall10bmwaround opening10bmiare substantially smooth and conforming to the surface ofexpandable member10emwhere they are to be joined.Buoyancy member10bmhas a maximum outside dimension (e.g., outside diameter, or other cross-sectional dimension) that permits it, together with device compressed down around it, to be inserted through a small incision in a patient. Examples of such maximum outside dimension are those described above with regard to the maximum outside diameter ofrigid portion10bmrinFIG. 13, although larger maximum outside dimensions may be alternatively used in embodiments wherebuoyancy member10bmis compressed for the insertion, as noted above.FIG. 16B is a cross-sectional view of thebuoyancy member10bmofFIG. 16A taken alongline16B-16B.
• FIG. 17 illustrates amandrel20 that is shaped to conform to theopening10bmiinbuoyancy member10bm. Accordingly, after molding thebuoyancy member10bmin the form shown inFIG. 16,buoyancy member10bmcan then be stretched overmandrel20 where is temporarily fixed thereon. Ashaft20scan be controlled to dip the buoyancy member (on mandrel20) into a vat of polymer to form a sealing layer or skin over the external surface ofbuoyancy member10bmto further reduce the gas permeability thereof. Multiple dips may be performed to form multiple coats of this skin layer if desired. For example, a vat of silicone may be provided to dip-mold a layer of silicone overbuoyancy member10bm. A typical thickness of the layer coated by dip-molding is about 0.005″ to about 0.030″. By completely submergingmandrel20 andbuoyancy member10bmin the molten polymer in the vat, askin layer10bmk(shown in phantom inFIG. 16B) can even be formed over the mandrel portion that fills theopening10bmi. Upon completion of the coating and curing of the coating layer, this skin layer can be slit to remove themandrel20 and theskin layer10bmkcan then be closed back over by patching with a layer of silicone plus room temperature vulcanizing silicone adhesive for example. Alternatively, a thin sheet of silicone can be bonded over the opening in the foam product, using room temperature vulcanizing silicone adhesive for example. This could optionally be further dipped in silicone to even further ensure sealing. Further alternatively, this portion ofbuoyancy member10bmcan be left open as it will be closed off by sealing buoyancy member against an inner wall surface ofexpandable member10em.
• Alternatively, a sealing layer or skin can be molded over the foam buoyancy member by liquid injection molding (LIM). Using this approach, after the foam molded product is removed from its mold, it is inserted into a second mold that is slightly larger than the mold used to mold the foam product, but the same overall shape. Liquid silicone is then injected into the second mold in the space that surrounds the mold to thereby mod a skin layer between the foam product and the walls of the second mold. This process may be advantageous in that it can provide greater control over the consistency of the thickness of the skin layer over the foam product, and a single molding step may be performed, rather than repeated dipping steps.
• Alternatively, an encapsulation layer may be fabricated separately, for example, by LIM or dip-molding. This layer can be assembled around the foam shape, and sealed off to provide complete encapsulation.
• Alternatively, thegap10bmabetween thewalls10bmwleading to opening10bmican be greatly reduced by molding in a shape illustrated in the cross-sectional view ofFIG. 16C, to provided a broadflat surface10bmbto increase the surface area to be adhered to the inner surface of a wall ofexpandable member10em.Gap10bmamay be made small enough so that it can be closed by simply compressing the components of10bmbtogether after placing RTV silicone adhesive therebetween. The gap can be about 0.01″ to about 0.50″, for example, or the gap can start completely closed, and then slit open to allow the internal mold to be released, and the slit can then be glued closed. In this case, the internal mold needs to be held in position during molding, and therefore there will likely be a portion of the internal mold that extends outwards and links to the outside mold. This link will result in a hold in the foam shape, therefore there may be more than a slit to close. For example, one or two patches may be required to form the complete closure. Alternatively, the process of bonding the foam buoyancy member to theexpandable member10emmay provide an opportunity to close off the molded openings and the slit.
• FIG. 16D illustrates thebuoyancy member10bmbhaving been closed by adheringgap10bmaclosed. Alternatively, or in addition thereto, a thin sheet of silicone can be bonded over thebacking surface10bmb, using room temperature vulcanizing silicone adhesive for example. This could optionally be further dipped in silicone to even further ensure sealing. Further alternatively, thegap10bmaofbuoyancy member10bmcan be left open as it will be closed off by sealingbuoyancy member10bmagainst an inner wall surface ofexpandable member10em.FIG. 16E illustrates a sectional view of the buoyancy member ofFIG. 16B in an embodiment where a thin layer ofsilicone10bsihas been bonded overskin layer10bmk, using room temperature vulcanizing silicone adhesive for example, thereby rigidifyingbuoyancy member10bmto fortify its function as an internal spine member, and also providing additional sealing in of thegas cavity10bmi. As noted above, this foam portion of the buoyancy member can alternatively be completely encapsulated in a separate encapsulating layer.
• FIGS. 18A-18J illustrate alternative configurations for forming structural type buoyancy members, i.e., that do not need to be inflated or expanded in use, but retain a volume of gas therein to provide buoyancy forces when implanted as part ofdevice10. Any of these structures can be used to make thebuoyancy members10bmshown inFIGS. 14 and 15 for example.FIG. 18A is a construction that includes atubular structure10bmwwhich may be a polymer such as silicone, polyurethane EVOH, or other polymers described herein, as well as layers of one or more of these materials. Other examples include polypropylene and silicone structure, with silicone foam; or high density polyethylene or low density polyethylene with silicone. One or more foam struts10bms(FIG. 18A shows two), are inserted in the open space formed by thetubular structure10bmwto increase the overall structural rigidity and resistance to collapse of the tubular structure, while still maintaining some gas within the foam struts. It should be noted here that this construction does not have to be formed as a tube, or tubular eggplant shape, as the outer wall could be formed as a disk or other structure, for example. The previous statement applies to all of the embodiments inFIGS. 18A-18J.
• InFIG. 18B,buoyancy member10bmis formed with a foam-like or sponge-like structural arrangement that encapsulates small gas pockets and therefore does not have to be inflated after placement ofdevice10 in the abdominal cavity. In this example, struts10bmsare formed integrally withwall10bmwfrom the same material, which is not a foam, but one or more of the polymers already referred to.Struts10bmsare separated bypockets10bmgin which gas is encapsulated, as the structure is completely closed off bywalls10bmw. Alternatively, the entire mass ofFIG. 18B may be “normal” silicone (i.e., not foam) with a design that has a built-in structure so that it can be compressed, but then springs open and holds its shape open after being inserted into the abdominal cavity. The air cavity within this structure provides sufficient buoyancy to offset the additional density of the “normal” silicone, as compared to foam.
• InFIG. 18C, thewalls10bmwof buoyancy member are supported bytubes10bmtthat may be made of foam, or alternatively may be made of polymer sheeting, which may be of the same formulation aswall10bmw. In one particular embodiment,walls10bmware silicone andtubes10bmtare formed of silicone. In another particular embodiment,walls10bmtare formed of silicone andtubes10bmtare formed of high density polyethylene or low density polyethylene. Stillfurther tubes10bmtmay be made of silicone foam, polyethylene foam or silicone that is not foam (“normal” silicone).Tubes10bmtprovide structural support to buoyancy member to keep it from collapsing under pressure imposed by the liquid inexpandable member10em. At the same time, the annuli intubes10bmtencapsulate gas. Additionally, gas is encapsulated in the walls of thetubes10bmtwhen they are formed of foam. Still further, gas is encapsulated in the gaps orinterstices10bmgbetween thetubes10bmt.
• The embodiment ofFIG. 18D may include any of the same material construction configurations described with regard toFIG. 18C. The embodiment ofFIG. 18D however has only a single row or column of tubes18bmtand this makes the structure less rigid and relatively easier to bend along the longitudinal axes of thetubes10bmt.
• The bending strength ofbuoyancy member10bmmay be modified and tailored by making one ormore tubes10bmtdiscontinuous and by altering the lengths of the discontinuous tube(s)10bmtas illustrated inFIG. 18E.
• FIG. 18F illustrates a buoyancy member structurally supported byribs10bmmmolded into the shaped thatbuoyancy member10bmis desired to maintain.Walls10bmw, which may be silicone, for example, completely encapsulate theribs10bmmthereby sealing the structure and encapsulating gas in thegaps10bmg.
• InFIG. 18G, acolumn structure10bmcis provided to join opposingwalls10bmwand thus provide column strength tobuoyancy member10bmto maintain it in the configuration shown, thereby maintaining a volume ofgas spaces10bmgin which gas is encapsulated. It is noted that various other structure support members may be molded intowalls10bmwor positioned against the inner surfaces ofwalls10bmw, or otherwise arranged to assist in holding theinner chamber10bmiopen to maintain a volume of gas to provide buoyancy. For example, any of the types of structural members described in provisional application No. 60/877,595 to assist in holdingexpandable member10emopen (for example, seeFIGS. 9A-15D,19A and21-26B) can be used to help maintain the inner chamber ofbuoyancy member10bmopen.
• InFIG. 18H, a honey-comb-like arrangement of structurally supportingtubes10bmtis provided.10bmg. This structure can be encapsulated in a layer of polymer such as silicone, polyurethane, polyethylene, EVOH, or the like, or combinations thereof, thereby sealing off the annular spaces of the tubular members aw s well as the interstices between the tubular members.
• FIG. 18I illustrates afoam sheet10bmhthat can be cut out in a two-dimensional shape that can then be shaped into a three-dimensional shape and bonded to an inner surface ofexpandable member10emto form abuoyancy member10bm. For example,sheet10bmh, could be manipulated to form an eggplant-shaped buoyancy member bonded toexpandable member10em, like shown inFIG. 15. Clearly,sheet10bmhcan be cut out to form many other varying shapes of three dimensional buoyancy member when bonded to theexpandable member10em. By rolling the edges of thesheet10bmhand bonding them to an inner surface ofexpandable member10em, aninner chamber10bmiis formed that encapsulates gas therein. The sheet can be encapsulated to provide an additional barrier between the gas within the foam and the saline outside the foam. The encapsulation layer can be assembled around the foam, or dipped onto it, or established by LIM. The encapsulation layer (as well as any other encapsulation layers or other coatings described herein) can be further coated on the outside with a layer of parylene to provide a better barrier to fluid permeability.
• FIG. 18J illustrates an embodiment formed like described with regard toFIG. 18A (only with onestrut10bms), but is shown to illustrate more generally, that any of the embodiments described above can be molded or otherwise formed with a predetermined curvature designed to conform to the contour of the inner wall of expandable member (in the expanded configuration) to which it is to be fixed. Although shown open ended, both ends of buoyancy member are sealed off in the final product to encapsulate the gas therein.
• FIG. 18K illustrates an embodiment whereinsheet10bmhis provided with one ormore struts10bmsortubes10bmt(which may be foam or any of the other materials discussed above) to provide structure support to maintain the three-dimensional shape ofsheet10bmhas it is sealed to the inner surface of a wall ofexpandable member10em, and to help maintain the gas in the chamber formed thereby.
• An alternative method of partially or completely foam filling a buoyancy member includes molding thebuoyancy member10bmin the desired shape, bonding all but an inferior portion of the wall edges10bmwto an inner surface ofexpandable member10em, and then inserting a foam insert, either shaped to completely fill the moldedbuoyancy member10bmor to provide structural supports (struts, tubes, or the like), after which the remaining inferior portion of thewall edge10bmwcan be sealed to the inner surface of theexpandable member10em.
• FIGS. 19A-19B illustrate two different examples of molded buoyancy members that can be used as an internal spine like described above with regard toFIGS. 15-16. InFIG. 19A, the foam body ofbuoyancy member10bmis molded to have a constantly transitioning increase in outside diameter/dimension from a small end111 through amiddle portion11mto a large end11s. The thickness ofwall10bmwalso gradually increases with a tapering increase of thickness from small end11ithroughmiddle portion11mto large portion11s. Likewise, the inside diameter ordimension10bmidthat defines thegas cavity10bmigradually transitions or tapers from a smallest dimension at the small end and constantly increases through themiddle portion11mto the large end portion11s(where it then necessarily rounds off to close the end of thebuoyancy member10bm). In one particular embodiment,buoyancy member10bmhas an outside diameter ordimension10bmodat the small end11iof about 0.85″ which constantly transitions to an outside diameter ordimension10bmodof about 1.85″ at the large end11s; a thickness ofwall10bmwof about 0.125″ at small end11iconstantly increasing to a thickness ofwall10bmwof about 0.225″ at large end11s; and an inside diameter ordimension10bmidof about 0.60″ at small end11iconstantly increasing to the largest diameter or dimension of about 1.40″ at the large end portion.
• InFIG. 19B, the foam body ofbuoyancy member10bmis molded to have a constantly transitioning increase in outside diameter/dimension from small end11itomiddle portion11m, and then remains substantially constant frommiddle portion11mto large end11s. The thickness ofwall10bmwalso gradually increases with a tapering increase of thickness from small end11itomiddle portion11mand then remains substantially constant throughmiddle portion11mand large portion11s. Likewise, the inside diameter ordimension10bmidgradually transitions or tapers from a smallest dimension at the small end11iand constantly increases tomiddle portion11mand then remains substantially constant throughmiddle portion11mand large end portion11s(where it then necessarily rounds off to close the end of thebuoyancy member10bm). In one particular embodiment,buoyancy member10bmhas an outside diameter ordimension10bmodat the small end11iof about 1.05″ which constantly transitions to an outside diameter ordimension10bmodof about 1.50″ at themiddle portion11mand this dimension remains about 1.50″ through to the large end portion11s; a thickness ofwall10bmwof about 0.175″ at small end11itapering up to a thickness ofwall10bmwof about 0.20″, which remains substantially constant through the middle andlarge end portions11mand11s, respectively; and inside diameter ordimension10bmidof about 0.70″ at small end11itapering up to a diameter ordimension10bmidof about 1.10″ at themiddle portion11mand the large end portion11s.
• Although appearing flat in the two dimensional illustrations ofFIGS. 19A and 19B,buoyancy member10bmmay be formed with a twist along its longitudinal axis, so that the exposedwall edge10bmwshown is not planar, but follows a curvature resulting from the twist that is determined to better follow the contour of the inner surface ofexpandable member10em.FIG. 16 attempts to illustrate this curvature resulting from the twist.FIG. 20 also illustrates this curvature, withbuoyancy member10bmfixed to the inner surface ofexpandable member10emat a portion that twists from the inferior attachment location moving toward the superior attachment location. It is further noted that the wall ofexpandable member10emcan be reinforced in the location where buoyancy member is attached thereto, as described in greater detail below. WhileFIG. 20 illustrates what appears to be a curvature in one dimension (in the plane of the paper), the curvature may additionally be in a second dimension (in and out of the paper). Such a complex curvature may best fit the complex curvature of the inner surface ofexpandable member10emwherebuoyancy member10bmis attached. Such a complex curvature allows the spine/buoyancy member10bmto start and end at the most desirable locations to structurally support theexpandable member10em. For example, in this embodiment, the start point is among the attachment tabs150 (e.g., seeFIG. 22). The structure of thespine10bmthen extends from the abdominal attachment location of theexpandable member10emto the furthest apex ofexpandable member10emand thus performs two functions: 1) spine/buoyancy member10bmprovides structure which helps to transfer the weight of the cantileveredexpandable member10em(when anchored to the abdominal wall) back to the abdominal attachment; and 2) spine/buoyancy member10bmprovides the most buoyancy at the apex portion/superior portion ofexpandable member10em, so as to minimize twisting forces and lifting on inferiorly located portions.
• FIG. 21 shows an alternative embodiment ofbuoyancy member10bmthat is molded from foam and has a twisted teardrop or eggplant shaped conformation. In this embodiment thewalls10bmware thinned down, relative to previous embodiments described, by scalloping to reduce the overall weight of the molded product.Ribs10bmriare molded in to extend from the inside surface of the wall in the locations of the scallops to provide additional rigidity for to hold open thespace10bmito maintain a desired volume of gas therein to provide buoyancy. In one particular embodiment,buoyancy member10bmis molded from silicone foam into this conformation. Alternatively, buoyancy member can be made from normal silicone, wherein the volume of air in the internal chamber ofbuoyancy member10bmprovides sufficient buoyancy to offset the weight of the normal silicone and still provide enough buoyancy to help offset the weight of the saline inexpandable member10em.
• FIG. 22 illustrates an embodiment ofdevice10 havingbuoyancy member10bmattached to an inner wall surface of expandable member to form an internal, buoyant spine in a manner as described above.Expandable member10emfurther includes areinforcement layer160 that extends over a majority of the length ofexpandable member10emand may extend over substantially the full length ofexpandable member10em. The portion of the wall ofexpandable member10emcovered byreinforcement layer160 typically includes at least the area opposite the area the buoyancy member is attached to, and may include a substantial margin beyond this area in any direction, up to and including all directions, such as is shown inFIG. 22, for example.Reinforcement layer160, provides structural support ofexpandable member10emto reduce chances of the expanded configuration kinking by bending along its longitudinal axis. Cyclic actions of such kinking can produce wear and even failure of the expandable member, so the addition ofreinforcement layer160 performs a useful stiffening function. Together withbuoyancy member10bmfunctioning as an internal spine, this arrangement ofreinforcement layer160 andbuoyancy member10bmprovides even more structural support to prevent kinking and otherwise maintainexpandable member10emin its desired orientation in the expanded configuration.
• Reinforcement layer160 may be made, for example, of silicone sheeting reinforced with a strengthening material such as woven polyester, polytetrafluoroethylene, or the like. A margin of unreinforced silicone can be maintained all around the edges of the sheet to facilitate bonding toexpandable member10emand to avoid stress concentration at the edges. Bonding can be performed, for example, using room temperature vulcanizing silicone adhesive, or vulcanizing a sheet or cut form of unvulcanized rubber, for example. Alternatively,reinforcement layer160 may be made from a different polymer, such as polyurethane, for example, and reinforced with polyester mesh, for bonding onto aexpandable member10emhaving a polyurethane outer wall surface.
• Alternative formulations from whichexpandable member10emmay be made include, but are not limited to: polyurethane compositions including silicon-containing chain extenders, such as taught in U.S. Pat. Nos. 6,420,452 and 6,437,073, for example, or segmented block polyurethane copolymers, such as taught in U.S. Pat. No. 5,428,123, or other combined polymer compositions of polyurethane and silicone resulting in less permeability (to gas and/or liquid) than that of polyurethane used alone, or silicone used alone. Additionally, these improved barrier (resistance to permeation) properties can be achieved with a thinner wall thickness than would be required if using polyurethane alone, or silicone alone. Optionally,buoyancy member10bmmay also be made from any of these same materials. U.S. Pat. Nos. 6,420,452; 6,437,073; and 5,428,123 are hereby incorporated herein, in their entireties, by reference thereto.
• To facilitate anchoring ofdevice10,device10 may be provided with one ormore attachment tabs150. Attachment tab(s)150 fan out like wings from the surface of expandable member103mto provide a much broader attachment surface area compared to what would be provided by simply attaching the portion of theexpandable member10em, from which they extend, to a structure.FIG. 22 illustrates a singlecontinuous attachment tab150 that extends fromexpandable member10emabout a circumferentially extending portion of the surface of the inferior portion ofexpandable member10em.Attachment tab150 may be bonded to the surface of expandable10em, such as with silicone dip layer, for example, or using room temperature vulcanizing silicone adhesive, or using unvulcanized silicone sheeting between tab(s)150 andexpandable member10emand then vulcanizing by heat pressing. By bonding to a portion ofreinforcement layer160, stress forces generated by movements of the patient, for example, through attachment tab(s) which are anchored to the patient, can be distributed over thereinforcement layer160. Additionally, border portions of tab(s)150 can be sandwiched betweenexpandable member10emandreinforcement layer160, thereby further reinforcing the connection between attachment tab(s)150 andexpandable member10em. If the attachment tab(s) is/are made from polyurethane to be bonded to a polyurethaneexpandable member10emwall, a solvent bond can be performed using a slurry mixture of polyurethane. By extending the superior edge oftab150 continuously and integrally across the width ofexpandable member10em, this strengthens the bond and eliminates stress concentrations that could lead to delamination of tabs individually bonded to opposite side portions ofexpandable member10em.
• Alternatively,multiple attachment tabs150 can be placed at locations aroundexpandable member10emto extend from and substantially cover areas covered by the largersingle attachment tab150 shown inFIG. 22, although this may introduce locations of stress concentration at the bonded corners of the individual tabs150 (e.g., peel force attempting to peeltab150 away fromexpandable member10em), as noted. However, an advantage is provided by multipleindividual tabs150 in that the tabs are more easily able to conform to the structure that they are being attached to, particularly if there is some curvature or other surface shape other than planar in the structure. That is,tabs150 can be overlapped to reduce the overall coverage of the structure to be attached to and this increases the convexity of the attachment surfaces formed bytabs150, ortabs150 can be otherwise changed in relative position to better match a surface shape to be conformed to, or spread apart to increase the concavity of the attachment surfaces formed bytabs150, for example. The overlapping prevents folds or wrinkles that would otherwise occur with asingle tab150 such as like that inFIG. 22. The use of attachment tab(s)150 also gives the surgeon the option to not useconduit12 to perform an anchoring function. This allows an access member connecting to conduit outside of the abdominal wall to be placed further away from the ribs, potentially offering the patient less discomfort, and also allowsconduit12 to be placed so that it is not under tension to perform an anchoring function, thereby lessening the mechanical requirements forconduit12.Attachment tabs150, although typically located to extend from the inferior portion ofexpandable member10em, need not be so located, but can be placed to extend from any locations ondevice10 orexpandable member10em.
• Tab150 will typically be formed from a reinforced sheeting, such as polyester-reinforced silicone sheeting, polypropylene-reinforced silicone sheeting or polyethylene-reinforced polyurethane sheeting for example, or any other biocompatible fabric that can be sandwiched between two layers of biocompatible polymers or rubbers. One ormore patches152 of tissue ingrowth enhancing material, such as a expanded polytetrafluoroethylene, polytetrafluoroethylene, polyester, etc, in felt or velour configuration, or polypropylene mesh, for example, can be bonded onto the reinforced sheeting so that, when placed in contact with tissue, tissue is encouraged to grow into the patches. An additional tissueingrowth enhancing patch152, such as the circular one illustrated inFIG. 22 may be provided through which anelongated positioning loop170 may extend, as illustrated inFIG. 23. This tissueingrowth enhancing patch152 not only encourages tissue ingrowth from the tissue location to which it is drawn against by positioningloop170, but also reinforces the junction ofpositioning loop170 todevice10, strengthening the junction.
• FIG. 22 illustratesdevice10 including theoptional positioning loop170 connected toexpandable member10emthrough tissueingrowth enhancing patch152 and optionally toreinforcement layer160.Positioning loop170 is typically a long lightweight loop of polymer, such as a ribbon and may be formed from polypropylene mesh ribbon or the like. After insertingdevice10 through an opening in the patient and into the abdominal cavity (positioning loop170 is also inserted into the abdominal cavity), a surgeon can form an additional puncture through the patient at another location in the abdomen in line with a location on the abdominal wall where it is desired to anchor the inferior end portion ofdevice10 to the abdominal wall. This puncture can be very minimal and performed using a needle, needle that includes a hook, or other sharp, minimally invasive tool. Using the same tool or a different minimally invasive hook tool or graspers,loop170 is captured and drawn out through the additional puncture. By applying tension topositioning loop170, the inferior end portion ofdevice10 and particularlyingrowth patch152 can be drawn up against the internal surface of the abdominal wall for anchoring there. Anchoring of the tab(s)150 can be done prior to or after inflation ofexpandable member10em. In one typical example,expandable member10emcan be expanded with gas or liquid prior to anchoring to facilitate proper positioning ofdevice10 prior to anchoring tab(s)150. One practical approach is to inflateexpandable member10emwith gas to check for positioning, since inflation with gas is faster and easier than inflation with liquid. Once proper positioning is confirmed,expandable member10emcan then be quickly deflated, and anchoring of attachment tab(s) can then be performed. By performing anchoring of attachment tab(s) withexpandable member10em, this provides more working space and/or better visibility to accomplish the anchoring. After anchoring,expandable member10emcan then be inflated with liquid. The ribbon portions ofloop170 adjacent the exterior surface of the abdominal wall can be sutured or otherwise fixed to the abdominal wall, and the portions ofloop170 proximal of the fixation location can be severed and removed from the patient.
• FIG. 24 illustrates an exploded view of reinforcement tab and loop structures, demonstrating one method of bonding these structures toexpandable member10em. In this embodiment, dual reinforcement layers160aand160bare provided. Positioning loop extends through openings provided in the reinforcement/tissue ingrowth patch152,tab150 andreinforcement layer160b, and the ends of theribbon170 are bonded to theinner reinforcement layer160a.Tab150 is bonded toouter reinforcement layer160band reinforcement/tissue ingrowth patch152 is bonded totab150 or toouter reinforcement layer160b.Outer reinforcement layer160bis bonded toinner reinforcement layer160aaccording to any of the techniques described above forbonding reinforcement layer160 toexpandable member10em, thereby sandwiching and securely anchoring the free ends ofribbon170 therebetween. The resulting construct can be bonded toexpandable member10emaccording to any of the techniques described above forbonding reinforcement layer160 toexpandable member10em.
• FIGS. 25A-25C illustrate additional tab features that may be provided ondevice10, such as onexpandable member10emto assist in positioning/repositioning the device in the abdominal cavity.FIG. 25A illustrates a portion of the outer surface ofexpandable member10emto which is bondedpositioning tab154. This positioning tab has a base154bbonded to the surface of theexpandable member10emand a extending portion, such asfin154eor other tab extension that does not lie flush with theexpandable member10emsurface, but extends therefrom to allow a surgeon to grasp this portion using endoscopic graspers or other tool that can be inserted through a small opening in the patient to perform a grasping function. Once grasped, the tool can be pulled, pushed or otherwise manipulated to move the position of theexpandable member10em. The cross sectional view ofFIG. 25B more clearly shows the extendingfin portion154eofpositioning tab154.
• FIG. 25C shows apositioning tab154 that lies substantially flush with the surface ofexpandable member10em. However, only the central portion of tab154 (bondedportion154b) is bonded toexpandable member10emwith the borders154fleft unsecured. Accordingly, graspers or other instrument can grab a portion of the free perimeter154fat the border ofpositioning tab154 to apply forces therethrough to move the position or orientation ofexpandable member10. In either configuration, one or more positioning tabs can be bonded at any locations on theexpandable member10emthat a surgeon may find useful to apply leverage to position or orient the expandable member.
• FIGS. 26A-26B illustrate an embodiment where tab(s) is/are extended to provide a shell-like rigidifying support ofexpandable member10em.FIG. 26A shows the anterior surface oftab150 andexpandable member10emshowingtab150 extending over a majority of the length ofexpandable member10em. Thisextended tab150 can be bonded toexpandable member10emwith or without one ormore reinforcement layers160 therebetween, as well as with or withoutstress relief feature160F.FIG. 16B shows the posterior surfaces oftab150 andexpandable member10emshowing thattab150 wraps partially (or optionally, completely) around the posterior surface of expandable member, forming both inferior andsuperior bands150b.
• FIG. 26C illustrates a configuration where a reinforced frame structure orreinforcement backing layer160 extends superiorly oftabs150 and may be formed in sandwiched, laminated construction with a portion of tab(s)150 at an inferior portion of thereinforcement backing layer160. Astress relief feature160F may be provided at the reinforcement layer160-expandable member10em(optionally, as well as interface borders between tab(s) andexpandable member10em) to diffuse stress concentrations that would otherwise build up between thebacking layer160 andexpandable member10em, as there is a significant difference in compliance properties between the fabric reinforcedbacking layer160 and the non-reinforced polymer layer ofexpandable member10em. For example, when expandable member is made of silicone and backing layer is made of polymer fabric-reinforced silicone, stress-relief feature160F may be a bead of RTV silicone, or a cut sheet of unvulcanized silicone sheeting that is pressed and vulcanized to bond toexpandable member10emandbacking layer160.
• Tab(s)150 can be fixed to an internal abdominal structure (such as an internal surface of the abdominal wall for example) using staples or tacks in a manner as described in co-pending application Ser. No. (Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2), which was incorporated by reference above, or sutures, or Q-ring fixation members that are configured like the coil portion of key ring, that can be threaded into and through thetab150 and tissue for anchoring these together, or hooks, barbs, corkscrew type anchoring members, or other known anchoring arrangements.FIG. 27 shows an inferior portion ofdevice10 to illustrate an alternative arrangement for fixing or anchoring tab(s) to an internal abdominal structure, which may be an internal surface of the abdominal wall and/or other internal abdominal structure. In this embodiment, sutures180 are inserted through tab(s)150 at least one location (at least one location into and at least one location out of, respectively) to form a loop that can be drawn against by drawing on the free ends of the suture to draw the tab(s) up against an internal abdominal structure to be sutured thereto. In the embodiment shown, there aresingle sutures180 that pass into, through and out oftab150 and tissue ingrowth patch at one location in and one location out. Additionally shown are sutures180 (in pairs in this example, although this is not necessary) that pas into and out oftab150 at two different locations, one into and out of a firsttissue ingrowth patch152 and a second, into and out of an adjacent tissue ingrowth patch. It is noted that this arrangement is only exemplary, as other patterns ofsutures180 could be used to accomplish the method to be described hereafter. It is further noted, that in embodiments that employmultiple attachment tabs150,sutures180 that extend throughadjacent tabs150, when pulled on, can also be used to repositiontabs152 relative to one another prior to fixing them to the internal abdominal structure. For example, drawing opposite ends of asuture180 may drawadjacent tabs150 closer to one another and or cause them to partially overlap.Sutures180 may be provided with one or more knots orother enlargements182 that cannot pass through thetissue ingrowth patch152 ortab150, to preventsutures180 from sliding out of the tab(s)150.
• After insertion ofdevice10 through an incision in the patient and into the abdominal cavity, the inferior portion can be generally located against the internal abdominal structure that it is to be anchored to by forming a puncture aligned with that location and retractingloop170 therethrough to pull the inferior portion ofdevice10 into contact with the internal abdominal structure, as was described above. It is noted thatpositioning loop170 is not shown inFIG. 27 in order to clarify the illustration of thesutures180 shown and the routes into and out oftab150. Once positioning loop has been anchored extra-abdominally (such as to the external surface of the abdominal wall, as one example), additional punctures are performed through the skin of the patient to grasp and retrieve ends ofsutures180. Opposite ends of asuture180 are drawn through separate punctures that are generally aligned with the locations oftab150 where the particular suture end extends from. When both ends of anyparticular suture180 have been drawn through the respective puncture openings, the suture is then tied down by tying the two ends of the suture together and forming the tied knot as far down through the fat of the patient as possible, into contact with the fascia (or as close to the fascia as possible). This procedure is repeated for each pair of suture ends of eachsuture180.
• FIG. 28 schematically illustrates onesuture180 having been tied down to anchor a portion oftab150 to the inner surface ofabdominal wall127. After creating the puncture/small opening202 through the skin, subcutaneous tissues including fat,fascia127 andabdominal wall127 and retrievingpositioning loop170 therethrough, positioning loop is pulled to pull the inferior portion ofdevice10 including attachment tab(s)150 against the inner surface of the abdominal wall in a general location where it is desired to anchordevice10 thereto. To assist in this movement, the surgeon may optionally grasp one ormore positioning tabs154 that may be located superiorly of tab(s)150 onexpandable member10em, for example. Further orientation ofdevice10 may be performed after the inferior portion ofdevice10 is drawn against theabdominal wall127 viapositioning loop170, and this further orientation may also be facilitated by pushing, pulling or torquing on one ormore positioning tabs154.
• After fixing loop70 to the outer surface of theabdominal wall127 and/orfascia127fand removing the excess loop portion extending proximally of the fixation point, as described above, anadditional puncture204 is formed in a general location overlying a location from which one end ofsuture180exits tab150. The end is retrieved using graspers, or other minimally invasive retrieval instrument and pulled out of the patient's abdominal cavity and through the abdominal wall, optionally all the way out of the patient. Assuming there is at least oneknot182 formed in suture to prevent it from sliding out of tab(s)150, then the retraction of the first end of the suture can be done without concern for holding the other free end of the suture. In this case, once the first free end ofsuture180 has been drawn out of the abdominal cavity throughpuncture204, asecond puncture206 is formed in a location overlying a general location from which the other end ofsuture180exits tab150. the other one end ofsuture180. This second end of suture is then retracted out of the abdominal cavity throughpuncture206. Alternatively, first and second ends of thesuture180 can be retracted out of the abdominal cavity simultaneously throughpunctures204 and206, respectively. Either way, the two free ends ofsuture180 are then tied down together as close tofascia127fas possible. The knot formed between the two ends of thesuture180 is pushed down through the fat to be tied off at a location abutting, or as close to thefascia127fas possible. This procedure is repeated for eachsuture180, wherein additional pairs of punctures are created for retracting each additional pair of free ends of eachadditional suture180, respectively.
• In an alternative procedure, when pairs of sutures are provided, as in the arrangement shown inFIG. 27, for example, adjacent free ends of the pairs ofsutures180 can be tied down as close to the fascia as possible. For example, referring toFIG. 27, a first puncture can be made to drawnend180atherethrough and a second puncture can be made very close to the first puncture to drawend180btherethrough, and then ends180aand180bcan be tied down together, close to or abutting thefascia127f. Similarly, a third puncture can be made to drawnend180ctherethrough and a fourth puncture can be made very close to the third puncture to drawend180dtherethrough, and then ends180cand180dcan be tied down together, close to or abutting thefascia127f. An advantage to this technique is that because the ends to be tied together are so close to one another, the punctures to draw them out of the abdominal cavity can also be made very close to one another. This results in the tiedsuture loop180 surrounding much less fat and therefore there is a reduced chance of loosening of the tie due to fat loss before sufficient tissue ingrowth has occurred inpatches152. Another advantage is that since the punctures for the adjacent suture ends to be tied can be made so close to one another, they can both be made from the same incision or puncture in the skin of the patient, while moving the graspers or other puncturing or incising instrument only slightly to form a puncture next to one that has already been made.
• Alternatively, one or more ofsutures180 can be replaced byadditional positioning loops170 that are fixed to tab(s)150 in locations where the ends ofsutures180 would otherwise extend out of tab(s)150. Anchoring of the tab(s)150 can then be performed by pullingloops170 out of the abdominal cavity and tying them together in any of the manners described above with regard tosutures180.
• Further alternatively, it is noted thatdevice10 can be generally positioned for anchoring the inferior portion ofdevice10 without the use ofpositioning loop170, with or without assistance of positioning tab(s)154, and still anchor tab(s) usingsutures180 in any of the manners described above.
• Alternatively to separately manufacturing abuoyancy member10bmandexpandable member10emand then inserting (either with or without fixing to the expandable member)buoyancy member10bmintoexpandable member10em(either before or after insertion ofexpandable member10eminto the abdominal cavity),buoyancy member10bmmay be manufactured integrally withexpandable member10e.FIG. 29 shows amold15 that is three dimensionally shaped to formexpandable member10emandbuoyancy member10bmintegrally as a single molded product.Portion15emfrom the shape ofexpandable member10emandportion15bmextends fromportion15emto form the shape ofbuoyancy member10bm. After molding the polymeric material overmode15, a small slit can be made to peel the molded product off themold15.FIG. 30A illustrates the molded product after removing it frommold15 via slit10st, for example.Slit10stcan be closed by patching, such as bonding a sheet of silicone thereover using RTV silicone adhesive, for example, or by bonding with RTV silicone adhesive alone, or other equivalent sealing technique.
• By pushing on the portion of the product that will formbuoyancy member10bmin the direction of the arrows shown inFIG. 30A, this portion can be inverted inside the main body portion that formsexpandable member10em, as illustrated inFIG. 30B. This leaves an open channel orslot10sltin the wall ofexpandable member10emas illustrated in the right side view ofFIG. 30C. Thisslot10sltcan be closed by bonding a polymer layer (e.g., silicone sheet) over it, thereby closing off theinternal chamber10bmiand sealing gas therein. Alternatively, prior to sealing, a foam insert having a shape conforming to thebuoyancy member10bmcan be inserted therein to holdbuoyancy member10bmopen and, at the same time encapsulate gas therein. Further alternatively, a balloon or structural supporting elements of any of the types described above can be inserted into theinner chamber10bmiprior to sealing off theslot10slt.
• This technique is not limited to formation of abuoyancy member10bmhaving a teardrop or eggplant-like shape, but can be applied to many other shapes of buoyancy members. Likewise, the shape ofexpandable member10emis not limited to the shape shown. Further, this method is not limited to the placement ofbuoyancy member10bmas an internal spine as shown.FIG. 31 illustrates analternative mold15 in whichbuoyancy portion15bmis formed to extend superiorly of the superior portion ofexpandable member portion15em, and is closer to spherical shape than eggplant shape. Alternatively, this method of assembling thebuoyancy member10bmonto the side area ofexpandable member10emdoes not have to utilize a shape inexpandable member10emthat is inverted. For example, inFIG. 30A, without the shape of10bm, the shape of10emwould be more like what is shown inFIG. 30B. Given this shape, a flat sheet of foam can be adhered to the outside of the mold forexpandable member10em, and a layer of silicone could be layered over the foam to form the expandable member there.
• FIGS. 32A-32E illustrate steps that may be carried out during a procedure for implanting an expandableextra-gastric device10 according to an embodiment of the present invention. Prior to making an incision, the local area (the area of the skin in and surrounding the location where the incision is to be made) may be prepared by disinfecting with alcohol and or betadine. Additionally, the patient may be given a mild sedative or may be on conscious sedation. (Although not practiced in this particular procedure, a similar procedure could be practiced with placing the patient under general anesthesia, in which case anesthetics would not need to be injected as described in the next step.) Next a powerful local anesthetic such as marcaine (bupivicaine) or other powerful anesthetic, optionally mixed with an epinephrine or other vasoconstrictor to reduce any bleeding that might result from mild trauma, is injected into the local area through theskin125 of thepatient1 down to the muscular layer and to infiltrate the fat layer and entire local area. Injection may be performed using asyringe219, as illustrated inFIG. 32A, or other injection tool. After allowing time for the injected anesthesia to take effect, a small incision223 (e.g., no greater than about seven cm or no greater than about five cm) is made in theskin125 of thepatient1, with ascalpel229 or other surgical cutting tool, in the local area over the surgical target area wheredevice10 is to be implanted. In the example shown, theincision223 is made slightly inferior to thelower rib line114. (FIG. 32A shows a frontal schematic view of the abdominal portion of the patient1).
• A delivery tract is then opened from opening223 through the subcutaneous tissues and abdominal wall to provide an access opening into the abdominal cavity. For example, the delivery tract may be formed by starting with asmall incision223,225 and then inserting a small port under visual guidance (for example, with VISIPORT™, or the like) to provide safe access into the abdominal cavity. Alternatively, the delivery tract can be made with a cannula and a veress-style needle within it which is subsequently exchanged, after access into the abdominal cavity, with a wire, such asguidewire502 or a viewing wire to allow exchange of the cannula and insertion of a larger bore access sheath over a dilator over the wire. Once the delivery tract has been established,device10 in a compact configuration is inserted throughopening223 and advanced along the tract, through the opening in the abdominal wall and placed in the abdominal cavity.FIG. 32B illustratesdevice10 having been compacted to a substantially cylindrical configuration and being fed through theopening223. This compact configuration can be pushed along the tract without any other delivery mechanism. Optionally, a sheath or cannula17 (shown in phantom lines inFIG. 32B) may be used for delivery ofdevice10 therethrough.
• When theexpandable member10emhas been completely inserted into the abdominal cavity (which can be verified by laparoscope or by other indirect visualization apparatus for a percutaneous step, or both), and optionally anybuoyancy member10bmor insert for abuoyancy member10bmhas been inserted into theexpandable member10em, (in those arrangements where abuoyancy member10bmor portion of abuoyancy member10bmis inserted after placement ofexpandable member10eminto the abdominal cavity) then cannula orsheath17, if used, is removed from the patient and a puncture or very small incision is made in theskin125 at a location that generally overlies a location of the abdominal wall that the surgeon wants to anchor an inferior portion ofexpandable member10emto. The opening through whichdevice10 is inserted may range from about 5 mm up to about 5 cm, or up to about 7 cm. The punctures are much smaller that the opening through which thedevice10 is passed.
• Graspers784 or other instrument are then inserted through incision or puncture225, as illustrated inFIG. 32C, to puncture through the subcutaneous tissues, fascia and abdominal wall. It is noted here that if the instrument that is inserted has a sharp distal end, then the instrument may be used to form thepuncture225 through theskin125 during the same procedural step of puncturing through the subcutaneous tissues, fascia and abdominal wall, thereby eliminating the need for a separate step to form opening225. When the distal end of the instrument enters the abdominal cavity, it is maneuvered to capture (e.g., grasp, hook, etc.)positioning loop170. The instrument is then retracted out of the body of thepatient1 at the sametime pulling loop170 out throughopening225 as illustrated inFIG. 32D.Positioning loop170 is pulled as described above to draw the inferior portion ofexpandable member10emup against the interior wall surface of the abdominal wall and to generally locate it where it is to be anchored.Loop170 is then anchored to the external surface of the abdominal wall and/or fascia and the portion of loop extending proximally from the anchoring location is cut off and removed, as described previously. One ormore positioning tabs154 may be grasped or otherwise used to help move and orientdevice10 along with positioning bypositioning loop170. For example, another set ofgraspers784 can be inserted throughopening223 to grasp apositioning tab154 to assist in movements of thedevice10. Also, the instrument inserted throughopening225 can first grasp or otherwise temporarily attach to one or more positioning tabs (sequentially) to perform movements ofdevice10 prior to engagingloop170 and pulling it out of the abdominal cavity.
• When positioningloop170 has been anchored externally of the abdominal cavity, additional punctures or small incisions are made in order to perform the procedural steps for tying off the sutures180 (oradditional loops170 if they are provided to substitute for sutures180).FIG. 32E illustrates eight additional incisions orpunctures225a-225hmade to carry out the anchoring procedures for thesutures180 and/oradditional loops170, for an arrangement ofsutures180 and/oradditional loops170 shown inFIG. 27. It is noted that punctures/incisions225c-225fin this arrangement are used as entry points for establishing two adjacent punctures each through the fascia and abdominal wall.
• After completing the tying off or otherwise securing of thesutures180 and/oradditional loops170 is completed and suture material and/or suture loop material extending proximally from the ties is removed, the incisions/punctures225 are closed, such as by suturing. Anaccess member80 can be installed according to any of the techniques and in any of the locations described in co-pending application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2), in provisional application Ser. No. 60/877,595, in application Ser. No. 11/407,701, or as described herein.Buoyancy member10bm, if inflatable can then be inflated with a gas, andexpandable member10emcan be inflated with a liquid.Opening223, as well as, optionally, any additional opening that may have been created for installation ofaccess member80 are then closed off, such as by suturing, to complete the procedure. Alternatively, thebuoyancy member10bmcan be integrated with/or double as ananchoring frame600, as described in more detail below, which may allow for a smaller incision to be made in the patient, while still providing a buoyancy feature.
• FIGS. 33A-33K illustrate steps that may be carried out during a procedure for implanting an expandableextra-gastric device10 according to an embodiment of the present invention, in which the implantation may be performed through a singlesmall opening227 in the patient. This opening may be sized to have a length or diameter in the range of about 5 mm to about 5 cm, for example, or may have a length or diameter up to about 7 cm, for example. Prior to making theopening227, the local area (the area of theskin125 in and surrounding the location where the incision is to be made) may be prepared by disinfecting with alcohol and or betadine. Additionally, the patient may be given a mild sedative or may be on conscious sedation. Though not preferred, the procedure can also be carried out under general anesthesia.
• Next a powerful local anesthetic such as marcaine (bupivicaine) or other powerful anesthetic, optionally mixed with an epinephrine or other vasoconstrictor to reduce any bleeding that might result from mild trauma can be injected into the local area through theskin125 of thepatient1 down to the muscular layer and to infiltrate the fat layer and entire local area (the anesthetic portion of the mixture may not be needed if the procedure is performed under general anesthesia). Injection may be performed using asyringe219, as illustrated inFIG. 33A, or other injection tool. After allowing time for the injected anesthesia to take effect, access to the abdominal cavity is gained by insertion of a needle501 (e.g., veress needle) through theskin125 of thepatient1, in the local area generally over the surgical target area wheredevice10 is to be implanted. A conventional veress needle does not have a lumen for a guidewire. By adding a small sheath outside the shaft of the veress needle apparatus, a modified veress needle is created such that aguidewire502 can be easily introduced through the sheath. Optionally, this step may be visualized directly via a scope, asneedle501 can be provided with a scope. For example, alaparoscope503 can be inserted into a trocar504 (shown in phantom inFIG. 33A) having a blunt end that can be inserted which has a blunt distal end that performs effective separation of tissues as thetrocar504 andlaparoscope503 are advanced toward and into the abdominal cavity. By inserting thelaparoscope503 though this blunt-ended port/trocar, the tissues can be visualized as entry is made into the abdomen. When the surgeon sees intra-abdominal fat, the surgeon knows to stop pushing on the endoscope, or other instrument, since it is known that the abdominal cavity has been entered. Alternatively, a procedure may be done with a cannula, veress-like needle and dilator/sheath as described above. Additionally, or alternatively whenscope503 is note used, this step can optionally be visualized under fluoroscopy or other indirect visualization mechanism.
• FIG. 33B is a view of the ribs andstomach120 with an indication of the location on the surface of theskin125 through which needle501 and guidewire502 can be inserted.FIG. 33B illustrates that the location of insertion can be well below the xiphoid, to the left of midline, near the palpated edge of the costal cartilages (whereasFIG. 33A indicates that the insertion can alternatively be performed slightly inferior to thelower rib line114, as shown in the frontal schematic view of the abdominal portion of the patient1).
• A dilator, such as an access sheath orcannula535 having a tapering distal end portion that gradually increases in outside diameter from a distal end in a proximal direction can optionally be inserted over aguidewire502, as illustrated inFIG. 33C, after gaining access to the abdominal cavity with a cannula and veress-like needle and exchanging needle withguidewire502, in a manner as described above.
• FIG. 33D illustrates the insertion ofguidewire502 to follow the contour of the caudal surface of the left hemisphere of the diaphragm as it is pushed up and around thestomach120, as far as the spleen. The distal end ofguidewire502 may be provided in a “J” shape or other bent shape to make it more atraumatic. Alternatively, a rod may be inserted instead ofguidewire502, such as a rod that is stiffer than a guidewire and/or that has regions of varying stiffness or flexibility and/or that has an outside diameter greater than a typical guidewire and which may optionally include one or more lumens for fluid injection, suctioning, visualization, etc. Further alternatively, a flexible, steerable endoscope may be inserted in place ofguidewire502 and used as a guide rail for delivery of device10 (as well as, optionally, other devices or instruments) thereover and into the abdominal cavity, as described in more detail in copending application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2) Still further alternatively, a flexible wire that is similar in construction to guidewire502 may be inserted in place ofguidewire502, wherein the flexible wire is only slightly larger in cross-sectional diameter, and includes one or more optical fibers extending the length thereof, as described in more detail in copending application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2) Still further alternatively, more than oneguidewire502 or rod or flexible wire may be inserted. For example, ifdevice10 is designed to ride over multiple tracks on anchoringframe600, thenmultiple guidewires502 may be inserted, one for each track to ride over. Once theguidewire502 has been placed as desired, needle501 (if averess needle501 is used) is pulled off ofguidewire502 and removed. Adilator535 can be inserted, or series of increasinglylarger dilators535 can be sequentially inserted at this point to enlarge the opening through the patient. Ifdilator535 was used during the insertion ofguidewire502, then increased dilation can be performed by sequential removal and replacement of one or morelarger dilators535. The lastused dilator535 is left in position to function as aport535.
• Ananchoring frame600 and an anchoringframe delivery tool630 on whichanchoring frame600 is mounted (in any of the manners described in application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2 or herein) are advanced overguidewire502 and through dilator/port535 (seeFIG. 33E) after which anchoringframe delivery tool630 is operated to deliver anchoringframe600 into the target position along the abdominal wall, where it is anchored there. Prior to anchoring, the surgeon will check to ensure that no bowel, omentum or other tissue is located between the anchoringframe600/tool630 and theabdominal wall127. Optionally,instrument630 may be provided with a scope, either flexible or rigid to facilitate direct visualization of delivery and anchoring of theanchoring frame600. Alternatively, indirect visualization, such as fluoroscopy, electromagnetic visualization mechanisms, or other indirect visualization systems can be used. Further alternatively, both direct and indirect visualization may be used. Anchoring may be performed by a variety of different attachment means, including, but not limited to sutures, staples, adhesives, tacks, needles, or combinations thereof.
• After anchoring theanchoring frame600 to theabdominal wall127, anchoring frame delivery tool is then removed from dilator/cannula535 and offguidewire502.FIG. 33F illustrates a sectional view of the patient1 (viewed from the feet of the patient) that shows the anchoring of anchoringframe600 to theabdominal wall127, with the anchoringframe delivery tool630 having been removed.FIG. 33G is a schematic illustration from a frontal view perspective, showing theanchoring frame600 anchored in place against the anteriorabdominal wall127, as also shown in the sectional view ofFIG. 33F.
• Once anchoring frame has been anchored to the target location, as illustrated inFIGS. 33F and 33G, adevice deployment tool660 having already been preloaded with adevice10 in a collapsed or compressed configuration, is next advanced over theguidewire502 and over anchoringframe600 in any of the manners described in application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2) or herein, and as illustrated inFIG. 33H. Positioning of thedevice10 can be monitored during this delivery using fluoroscopy, X-ray, CT or MRI visualization guidance, for example, or simply via direct visualization with an endoscope, such as a flexible endoscope inserted through sheath/cannula535, for example, or extended throughdeployment tool600, or optionally, though not preferred, through another opening provided through the patient's skin and into the abdominal cavity.Device10 is advanced to the end of anchoring frame where it automatically locks into position there. Insertion of any of theanchoring frame600 and anchoring frame delivery tool,device10 and device delivery tool, and/or any of the instruments and/or devices used to access the abdominal cavity are typically performed without insufflation, but may be assisted by what is referred to “mini-insufflation” where the entire abdominal cavity is not insufflated, as in the typical insufflation procedure, but small bursts of insufflation gas are intermittently inputted to facilitate separation of anatomical structures to help develop the insertion path. Thus, a small burst could be associated with a small advancement of an instrument or device, followed by another small burst to help advance the instrument or device incrementally, and so forth, until the target location has been reached. Alternatively, impulses of liquid (e.g., saline) can be sprayed to accomplish the same task (e.g., to clear and path and provide enhanced visibility). Further alternatively, although not preferred, traditional insufflation can be performed. This would typically only be done when the less preferred option of using general anesthesia is also performed.
• FIG. 33I shows a sectional illustration ofdevice10 having been locked into position on anchoringframe600, withdevice delivery tool660 having been removed. At this stage, when the surgeon is satisfied thatdevice10 has been properly positioned and locked to anchoringframe600, cannula/port535 and guidewire502 are both removed. At least oneconduit12 will remain extending will remain extending fromdevice10, proximally out through theopening227 for inflation ofexpandable member10emand, optionally one ormore buoyancy members10bmwhen one or more inflatable buoyancy members are provided. The one ormore conduits12 can then be used to inflate the one ormore buoyancy members10bmwith gas (whenbuoyancy member10bmis of an inflatable variety) and to inflateexpandable member10emwith liquid. Further alternatively, one or more conduits may extend through theopening227 to allow a wire, strut, tube or other structural support member to be inserted to support eitherbuoyancy member10bmorexpandable member10em, or to insert abuoyancy member10bmintoexpandable member10em.
• Optionally,expandable member10emmay be inflated at this stage to test the amount of displacement and positioning of thedevice10 when in an expanded configuration, which may help to determine whetherdevice10 will perform as intended. One method of testing in this manner is with the use of an intra-gastric sizing device310 (e.g. an intra-gastric balloon catheter) in a manner as described in application Ser. No. 11/407,701 and application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2). Additionally, or alternatively, testing may be performed by visually observing the effects of expansion, such as by inputting radiopaque fluid into thestomach120, and/or by observing the expansion of the device when it is provided with one or more radiopaque indicators. Visualization, in such instances may be performed fluoroscopically or with other X-ray visualization, for example.
• At this time, any extending conduit(s)12 can be either clamped off to maintain the pressures withinexpandable member10em(andoptionally buoyancy member10bm), or the pressures can be released, thereby allowingexpandable members10em(and optionally,buoyancy member10bm) to at least partially deflate. It is easier procedurally to release the pressures and so this is typically done. However, the surgeon may choose to clamp off the conduit(s) to maintain at least partial pressure in at least theexpandable member10emto help maintain it in the observed position/orientation. In any case, conduit(s)12 is/are next trimmed to an appropriate length for connection with anadjustment member80, as illustrated inFIG. 33J.
• Conduit(s)12 are connected to a mating connector onadjustment member80 or to adeployment tool370 configured to mateconduit12 withadjustment member80, and, after connection ofconduit12 toadjustment member80, adjustmentmember deployment tool370 is then used to anchoradjustment member80 to the patient.Adjustment member80 can be anchored using anchoring members that may be made as any of a number of different configurations, including, but not limited to: protruding pins, protruding staples, moly bolt, snap fit with portion placed against interior abdominal wall surface; extendable hooks actuated upon torquing a portion of theadjustment member80 relative to another portion, etc. By advancingdeployment tool370 into the patient, the portion of conduit that had extended from thepatient1 is pushed back into the patient, until the adjustment member is positioned in the target location where it is intended to be anchored. This positioning can be verified using any of the previously described visualization techniques, or can be performed blindly, with feedback from palpitation, for example. In the example shown inFIG. 33K,adjustment member80 is anchored subcutaneously, to the external surface of theabdominal wall127. As has been disclosed previously in applications relied upon for priority and incorporated herein,adjustment member80 can alternatively be anchored subcutaneously, to an inner layer of the skin for example, or otherwise in thefat layer131 without being anchored directly to theabdominal wall127.
• Onceadjustment member80 has been anchored in the desired location,deployment tool370 is withdrawn andexpandable member10emis inflated with liquid to expand it to the desired size or pressure, andbuoyancy member10bm, if it is an inflatable variation can be inflated with gas to a desired pressure. This can be a re-inflation step if theexpandable member10em(and optionally the buoyancy member10bhad been previously inflated for testing and then deflated, or partially deflated. In this way, the patient can begin to experience beneficial weight loss from the effects ofdevice10 on thestomach120 beginning immediately after completion of the procedure, unlike current procedures, which typically require around six weeks before a return visit to “complete” the procedure to make it effective in helping weight loss. The same type or types of monitoring can be used here, as described in application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2), to provide feedback as to when theexpandable member10emand/orbuoyancy member10bmhas been expanded by the desired amount or pressure. Alternatively, expandable member may be left in an unexpanded or partially expanded configuration, with the patient being allowed to heal and then return to have theexpandable members10emfully inflated. Further alternatively,device10 may be implanted in combination with a constricting band, such as the LAPBAND™ or similar implant to improve results from such constricting band, or to make weight loss efficacious where prior implantation of such a constricting band has not been efficacious. For example, a constricting band generally useful for restricting the amount of solid food ingested by thepatient1. However, apatient1 may “cheat” the effectiveness of a constricting band approach by drinking high caloric liquids, for example. For example, a patient could drink a thirty-two ounce milkshake and this would pass right through the constriction established by the constricting band. However, withdevice10 implanted and expanded as described, the stomach is preventing from expanding, even by high caloric liquids.
• Once the surgeon is satisfied that theexpandable member10emhas been expanded by the desired amount and, optionally, the buoyancy member has been inflated to the desired pressure, or, alternatively, if theexpandable member10emis to be left in a contracted (unexpanded or partially expanded) state, the patient is closed, including, suturing theskin125 at the site of theopening227.
• Any of the variations of the procedural steps described above may be executed under indirect visualization, such as fluoroscopic visualization, 3-dimensional navigation or other CT/MRI guidance, or three dimensional RF or electromagnetic visualization (e.g., using pre-existing or real-time data sets from MRI, cat scan, three-dimensional ultrasound or other three-dimensional data set). Further alternatively or additionally, any of these procedural steps may be directly visualized using a scope such as a laparoscope or other flexible or rigid endoscope. A scope may also be integrated into a tool used to perform one or more of these steps.
• All tools referenced in the above procedure may include lumens to permit insertion of other tools and/or devices therethrough, including, but not limited to: endoscopes, wires, etc. and/or to allow delivery of suction, irrigation, and/or other substances. Alternatively to mounting theadjustment member80 toconduit12 in any of the manners described above, adjustment member may be pre-attached or integral withconduit12.
• No tissues around the stomach area are required to be dissected when performing the procedures described above with regard toFIGS. 33A-33K. This also applies to procedures described with regard toFIGS. 32A-32E. This is a major factor in why general anesthesia is not required to perform the procedures, why insufflation is not required, and consequently why these procedures can be performed in a physician's exam room and are not required to be performed in an operating room Further, with regard to the procedures described with regard toFIGS. 33A-33K, no tissue dissection is required other than that to perform the single entry location through the skin and abdominal wall. The single access port procedures make this a very minimally invasive procedure. Also, in all procedures described, no stapling or attachment to the stomach is required. That is, thestomach120 is not attached todevice10 in any way and is free to move relative todevice10 and to the other contents of the abdominal cavity, except for the constraints provided by the space occupied bydevice10. This greatly minimizes, if not eliminates problems of erosion experienced by prior art solutions that do attach to the stomach or pierce through the stomach wall, as force concentrations, such as shear force concentration are not built up betweendevice10 and thestomach120.
• FIG. 34 illustrates restriction of thestomach120 from expanding to its post-prandial, expanded configuration by implantation ofdevice10. As can be seen the fundus is substantially restricted from where it would otherwise normally expand and the stomach is restrained to a shape resembling a tube, not dissimilar to a shape resulting from a sleeve gastrectomy, but, of course achieved in a very minimally invasive manner. At least a portion of theantrum120ais left unrestrained to allow it to perform its normal functions, such as contractions to move food into the small intestines by ejecting it from thestomach120 with muscular contractions. Additionally, asmall pouch120pmay be left at the superior end portion of thestomach120 that provides a small capacitance or chamber for receiving food and then signaling the patient that it is full when this small chamber is filled, similar to a functionality provided by a banding procedure, such as the LAPBAND™ procedure, for example. Under conditions where the stomach is empty (e.g., has substantially no food in it),device10 may not exert any additional pressure (or only minimal additional pressure) to thestomach120. That is thestomach120 will experience substantially only “normal” abdominal pressures (i.e., close to the pressures that it would experience if there were no implant in the abdominal cavity). Thus, significant forces are only generated betweendevice10 and thestomach120 when the patient eats.
• With regard to procedural embodiments involving the anchoring of anchoringframe600 to an internal abdominal structure,FIGS. 35A-35D illustrate an alternative instrument and method to that described in application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2), e.g., seeFIG. 18B and the description thereof in application Ser. No. (application Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2).FIG. 35B illustrates a partial view of an anchoringframe deployment tool630, showing a distal portion ofshaft634 with anchoringframe600 mounted todistal end portion634d.
• Shaft634 articulates, via one or more articulatingjoints644 to movedistal end portion634dangularly relative to a portion ofshaft634 proximal ofdistal end portion634d. An articulation actuator646 (seeFIG. 35B) is provided on ornear handle632 oftool600 for operation by a user to control the articulation ofdistal portion634dofshaft634. In the example shown,articulation actuator646 is a rotatable wheel that is rotatable in a first direction to articulatedistal portion634din a first angular direction about joint644, while rotation ofactuator646 in the opposite direction articulatesdistal portion634din the opposite direction.Articulation actuator646 and/or articulation joint644 provide frictional resistance, so that whenactuator646 is not being rotated,distal portion634dis maintained in its orientation relative toproximal portion634p. Alternatively, the straight shaft portion6349 and articulation feature may be replaced by a curved shaft having no articulatingfeature644.
• Distal portion634dincludes a recess, cavity or slot650 configured to receive anchoringframe600 therein. Thus, recess, cavity orslot650 is shaped and dimensioned to receive anchoringframe600 therein and to confine anchoringframe600 from movements axially with respect to the longitudinal axis ofdistal portion634d.Frame600 may be received in recess, cavity or slot650 by friction fit and/or areleasable clamping mechanism651 maybe optionally provided on opposite sides of slot, recess orcavity650 for releasably clampingframe600 wherein it is received therein, with clamping and releasing motions being controlled by clamp actuator653.
• In use, after insertion and placement ofguidewire502, such as in a procedure as described above,deployment tool630 is passed overguidewire502, with the proximal end of guidewire first being inserted into the distal end ofshaft634, throughshaft634 and handle632 and proximally out ofhandle632, as illustrated inFIG. 35B. By insertion oftool630 into the abdominal cavity, the abdominal wall (e.g., the anterior abdominal wall can be accessed. This portion of the procedure, as well as other steps described below may be indirectly visualized using fluoroscopy and/or any of the other indirect visualization methods described above. Additionally, or alternatively,tool630 may be configured to receive an endoscope537 (shown in phantom inFIG. 35B) that can be used for direct viewing of the procedure. Thus,endoscope537 can be used to directly view the placement of anchoringframe600. Avideo camera538 may be provided onendoscope537 so as to monitor the visualization on a screen, or, optionally, viewing may be performed directly through an ocular.
• A window oropening648 may be provided proximally of articulating joint644 to enable viewing through the distal end ofendoscope537 that is positioned inshaft634 at the location of opening/window648 whenendoscope537 is inserted intotool630. Window/opening648 may be an opening (e.g., cutout), or may be a window, e.g., a cutout that is sealed over with a transparent material.
• Visualization, whether indirect, direct, or indirect and direct, is performed to ensure that there is no tissue located between the anchoring site (e.g., anterior abdominal wall127) and anchoring frame600 (seeFIG. 35A) prior to anchoring theframe600 to the anchoring site. Once it has been visually confirmed that there is no tissue intervening betweenframe600 and the anchoring site,actuator646 is manipulated to rotatedistal portion634dup against the anchoring site, thereby contacting surface a contact surface offrame600 to the anchoring site. Anchors610 in the form of elongatedflexible needles610nhaving sutures59 connected thereto and extending therefrom are next deployed through openings in theanchoring frame600, through the internal abdominal structure to be anchored to (e.g., the anteriorabdominal wall127 in this case) through thesubcutaneous fat layer131 and theskin125 and therefore out of thepatient1, as illustrated inFIG. 35C. This deployment may be actuated by anactuator647. For example,actuator647 may be connected to one ormore push rods631 that abut against ends ofneedles610nto provide a driving force to pushneedles610nthrough the internal abdominal anchoring site and other tissues noted above. Push rod(s)631 may be flexible, but have sufficient column strength so that it/they do not buckle under the compression put on them byactuator647 during deployment, but rather transfer the compression forces toneedles610nto move them out of the tool630 (distal end portion634d).Actuator647 may be connected aboutshaft634 for relative sliding with respect thereto viaslot647s.Needles610ncan be very thin, e.g., like acupuncture needles, and also have sufficient column strength to pass through the structures described without buckling.
• Needles610nare then disengaged from the needle delivery mechanism (e.g., push rods631). Needles601ncan be directly attached to sutures that reside within the channels of the delivery device (not shown). The back end of the sutures can be looped and held on a hook attached to a handle on the device to allow retraction of the needles into the device if initial deployment was not satisfactory. This hook mechanism can be actuated to release the sutures via a button on the handle when the needle locations are determined to be acceptable, allowing the suture/needle units to be pulled by the operation outward until they engage the anchoring platform. There are many other alternative mechanisms, widely known in the art, to grasp and release a thread like a suture, including mechanisms that cut the sutures from a fixed location, mechanisms that open up a clamp that was holding the sutures in a fixed location, mechanisms for releasing a lock on a spool where sutures are wrapped and initially retained within the deployment device, etc.
• Next, the surgeon, pulls theneedles610nthe rest of the way out of thepatient1, and continues this retraction until knots or other anchors (e.g., T-bars, or the like) at the ends ofsutures59 are stopped against anchoringframe600 Alternatively, sutures59 may be looped59kthrough anchoringframe600, so that adjacent pairs ofneedles610nare connected to opposite ends of a loopedsuture59. Theneedles610nare removed from thesutures59, leaving organized sutures precisely delivered through anchoring frame and the internal anchoring structure, precisely deliver through key strategic locations through anchoringframe600 designed to optimally secure theanchoring frame600 to the internal abdominal structure. Alternative embodiments may replace the sutures with other flexible members. For example, polypropylene mesh ribbons may be substituted. Further alternatively, a combination of sutures and mesh ribbons may be used, where theflexible member59 begins as a suture where it connects with the needle, and transitions into a ribbon. An advantage of a combination such as this is that the sutures are more easily delivered out through the abdominal wall, while the ribbons provide potentially better fixation to the abdominal wall.
• Sutures59 may be fixed externally of the abdominal cavity by tying them down, according to a procedure similar to that described above with regard toFIGS. 27-28 (e.g., by tying two suture ends together to form a loop), or aknot pusher tool669 can be used to slide a self-lockingclip667 that can be advanced distally oversuture59 toward theabdominal wall127, but which is configured to prevent backsliding in a proximal direction, oversuture59 and against the fascia or abdominal wall, or as close thereto as possible as there may be a small amount offat131 clamped betweenclip667 and the fascia/abdominal wall127, thereby securing a portion of anchoringframe600 to the internal abdominal structure (in this case, the inner surface of the anterior abdominal wall127) by the tension generated insuture59. The distal end ofknot pusher tool669 may have a sharp edge portion that can be used to cut off the portion ofsuture59 that extends proximally from the location ofclip667 in its fully advanced position. This cut off portion of the suture and theknot pusher tool669 are then removed from the patient. Each remainingsuture59 is thereafter sequentially tied/clipped down to securely anchor the entire anchoring frame, thereby forming an array of distributed anchoring forces distributed over the anchoringframe600.
• FIG. 35E is an illustration of the patient'sskin125 withneedles610nprotruding throughopenings228 formed by piercing theneedles610ntherethrough during performance of the step described with regard toFIG. 26C above. Anchoringframe600, which has been contacted against the anterior internal abdominal wall surface, is shown in phantom.FIG. 35F illustrates sutures509 extending fromopenings228 through the skin after removal ofneedles610n.
• FIG. 35G illustrates one embodiment of a suture lock orclip667 installed over asuture59.Clip667 can be freely advanced oversuture59 in the direction indicated by the arrow, but prevents sliding in the opposite direction, as teeth or cammed surfaces667tbite into thesuture59 if clip is attempted to be slid in the opposite direction, thereby preventing backsliding ofclip667.FIG. 35H illustrates a distal end portion or working end ofknot pusher tool669 being used to lock down aclip667 in a manner as described above.Tool669 includes adistal end pusher669pconfigured to interface with a proximal surface ofclip667 so as to form a secure engagement therewith as force is applied therethrough to pushclip667 alongsuture59.Tool669 further includes acutter portion669cproximal ofpusher669pand through which suture is threaded.Cutter portion669cincludes a sharp edge orblade669bthat can be actuated from a proximal end portion oftool669 once clip has been advanced oversuture59 as far as it is going to be advance to engage the fascia, abdominal wall, or fat near the fascia/abdominal wall. Actuation ofcutter edge669bcuts through thesuture59 leaving a short proximal tail that extends fromclip667 by a length about equal to the distance betweenpusher669pand cuttingedge669b.
• FIG. 35I illustrates another embodiment of aknot pusher tool669 wherein thecutter portion669cis axially aligned withpusher669p. Thus suture59 extend straight through the opening inpusher669pand the opening incuter portion669cout though the central lumen oftool669. Cutter portion includes a V-shaped sharpenededge669bthat may be beveled on the underside, so thatsuture59 freely passes over theedge669bastool669 is being advanced distally over thesuture59. However, as soon astool669 is retracted proximally with respect tosuture59, the beveled side of sharpenededge669bbegins to bite intosuture59 and forces it into the wedge-shape toward the apex of the V-shaped edge, thereby cutting the suture and leaving a tail having a length about equal to the distance betweenpusher669pand the apex of the V-shapedcutting edge669b.
• FIG. 36A illustrates an alternative arrangement ofneedle610nand anchoringmember59 that can be used for anchoring ananchoring frame600 in a manner like that described above with regard toFIGS. 35A-35I with variations described hereafter. In order to deploy needles to extend out through the abdomen of apatient1, needles610nmay need to be long enough to extend through the abdominal wall of an obese patient, e.g., on the order of about five inches to about eight inches, typically about seven inches. Accordingly as already noted, needles610ntypically require the ability to be bent without plastically deforming as they are redirected from extending in a direction along a length of a deployment instrument, to a direction substantially perpendicular thereto, to deliverneedles610nthrough theanchoring frame600, theabdominal wall127 and out of thepatient1.FIG. 36A shows only a portion ofdistal end portion634dthat contains a radiused portion of channel634chaving a controlled radius to redirectneedle610nthrough the anchoring frame600 (not shown inFIG. 36A, for simplicity), without plastically deforming theneedle610n. For example,needle610nmay be formed of superelastic material, such as nickel-titanium alloy.Needle610nmay optionally include derailing feature610pat or near the end opposite the sharp, leading end, that connects to the anchoring member and that, when contacting the radiused portion, does not enter the radiused portion, but “kicks out” sideways so that the anchoringportion59 does not need to be drawn through the radiused portion. Alternatively, the anchoringportion59 can be drawn through the radiused portion, following theneedle610n. The device that deploys the needles may have a mechanism for pushing the needles from a proximally locating starting position, where the starting positions of the needle tips are near the locations where they exit the device, and the needles, being quite long extend proximally along (within) the shaft of the device such that the proximal end of the needles having a starting location with the device shaft that is outside of the abdominal cavity. The mechanism pushes the needles along the device shaft to extend the needles outward to pierce through the abdominal wall. The needles have sufficient length so that they are still being pushed by the mechanism as the needle tips exit the skin of the patient. Once the needles are fully advanced, they are disengaged from the mechanical pushing mechanism. The user can then continue to draw the needles out of the patient and thereby draw the trailing suture./ribbon out through the abdominal wall. The mechanism for pushing the needles can be mechanical or pneumatic in nature, powered by energy inputted by the user, or by stored in energy in the mechanism, such as springs or compressed gas.
• Needle610nmay be alternatively connected to amesh ribbon59r, as shown inFIG. 36A, rather than asuture59.Mesh ribbon59rmay be made from polypropylene mesh, or the like, and may be made to be more durable than asuture59, both during assembly of the deployment device, as well as during deployment of theneedles610nandribbons59r. Alsoribbon59rhas lots of surface area, compared to asuture59, any portion of which can be easily engaged by barbs. In at least one embodiment,ribbon59rincludesdirectional barbs59bthat point away from the end of theribbon59rbeing pulled through the skin of thepatient1. Whenribbon59rhas been pulled sufficiently through the abdominal wall to draw anchoringframe600 against the inner surface of the abdominal wall, release of tension onribbon59rcausesbarbs59boutside of theabdominal wall127 and nearest to the outer surface of theabdominal wall127/fascia to catch against theabdominal wall127/fascia, thereby piercing into theabdominal wall127/fascia and flaring out radially somewhat, as illustrated inFIG. 36H. This securely anchorsribbon59r, preventing it from backsliding through the abdominal wall, and maintaining tension on anchoringframe600 to hold it against the abdominal wall. The barbs on the ribbons can be large features, or so small as to be a microscopic texture that achieves the same effect. The barbs can be utilized to engage into the tissue, or, alternatively, the large barbs can be used to lock into an externally loaded, washer-like implant that ratchets down the barbs and locks in place about the fascia, thereby preventing the ribbon and implant form moving away from the fascia. When deploying needles610nhaving mesh ribbons610rconnected thereto through the internal abdominal structure to be anchored to (e.g., the anteriorabdominal wall127 in this case) through the fascia andsubcutaneous fat layer131 and theskin125 and therefore out of thepatient1, after removingneedles610nfrom themesh ribbon59rportions extending out of the abdomen, mesh ribbons can be anchored externally of the abdominal cavity by tying them down, according to a procedure similar to that described above with regard toFIGS. 27-28 (e.g., by tying twomesh ribbons59rtogether to form a loop, or suture(s) can be used to tie theribbons59rto the fascia wall, optionally using device aids to place sutures, or aknot pusher tool669 can be used to slide aspeed nut667 that can be advanced distally overribbon59rtoward theabdominal wall127, but which is configured to prevent backsliding in a proximal direction, overribbon59r, similar to the method described with regard toFIGS. 35G-35I above.Speed nut667 can be advanced against the fascia or abdominal wall, or as close thereto as possible as there may be a small amount offat131 clamped betweenspeed nut667 and the fascia/abdominal wall127, thereby securing a portion of anchoringframe600 to the internal abdominal structure (in this case, the inner surface of the anterior abdominal wall127) by the tension generated inribbon59r.
• FIG. 36B illustrates an embodiment ofspeed nut667.Speed nut667 may be made of metal, such as stainless steel, nickel-titanium alloy or the like, or rigid polymer, either resorbable or non-resorbable.Speed nut667 may also be formed from a flexible plastic as long as the gripping features, such as barbs, spears or other gripping features are strong enough to maintain attachment ofspeed nut667 to the ribbon or suture it is anchored to.Speed nut667 is provided withbarbs667b, so thatspeed nut667 can be passed freely overribbon59rin the direction of the arrow shown (e.g., toward the abdominal wall), but if an attempt is made to slidespeed nut667 in the opposite direction relative toribbon59r,barbs667bengage in theribbon59r, through the holes already existing in the mesh ribbon, or by creating holes in a non-mesh ribbon, thereby stopping the motion and lockingspeed nut667 relative toribbon59rwith respect to motion in the reverse direction of the arrow shown. Such barbs can be designed as shown, or may have multiple teeth on the tip of each barb.FIG. 36C illustrates a plurality ofribbons59rhaving been anchored by fixingspeed nuts667 against the external surface of theabdominal wall127/fascia, optionally with a minimal amount of fat interposed, to distribute anchoring forces over anchoringframe600 which is drawn against the internal surface of the abdominal wall.
• FIGS. 36D-36E illustrate another embodiment of aspeed nut667 that is configured to assume undeployed (or extended) and deployed (or compressed) configurations or states.FIG. 36D shown the uncompressed or extended configuration. In this configuration,speed nut667 can be freely slid over aribbon59rin both directions. Oncespeed nut667 is slid to a desired location with respect toribbon59r, i.e., to a location where it is desired to lockspeed nut667 with respect toribbon59r,speed nut667 is compressed or deployed to assume the compressed or deployed configuration shown inFIG. 36E. This compression can be performed, for example, using graspers or some other endoscopic clamping tool, or a knot pusher tool may be configured to perform the compression function. In the compressed configuration,barbs667bare driven radially inwards, thereby piercing into theribbon59rto lock the position ofspeed nut667 relative toribbon59r. At the same time,flanges667fextend radially outwardly, thereby increasing the surface area against which the anchoring force is distributed, and functioning like a washer to reduce the risk of pull through of the speed nut through the abdominal wall. Additionally, lockingfeatures6671 engage one another, thereby lockingspeed nut667 in the compressed/deployed configuration.FIGS. 36F-36G show side and perspective views of another embodiment ofspeed nut667 havingmultiple barbs667b. Thedistal end portion667dhas an enlarged face/surface area than theproximal end portion667pto help distribute the anchoring forces. Design of any of these speed nuts attempts to keep thespeed nut667 to a minimum size to facilitate it's passage through the needle puncture in the skin, and facilitating passage through the fat layer, while making at least the distal end surface sufficiently large so that thespeed nut667 will not pull through the fascia or abdominal wall at the location where it is being anchored. In embodiments where thespeed nut667 is metal, there may not be a locking feature, as plastic deformation of the metal may be utilized instead to transform and hold the speed nut when driven from an undeployed to a deployed state. Further alternatively,speed nut667, whether made of metal or polymer or some combination, may be provided with flange elements that extend substantially parallel to the ribbon when in an undeployed state, and, once the speed nut is located where it is to lock the ribbon in position relative to the fascia, the flanges can be folded proximally to provide a larger surface area to prevent movement ofspeed nut667 through the fascia. Flanges may be bent until they collide with features on the speed nut that prevent further rotation thereof. This embodiment does not require locking mechanisms or plastic deformation to hold the flanges in their deployed configuration.
• In order to provide awider anchoring frame600 platform that is not limited by the diameter of the opening through the patient through which the anchoring frame is delivered, anchoringframe600 may be configured to be expandable, as illustrated inFIGS. 37A-37B. As shown, anchoringframe600 includes four expandable arms orbeams600a. However, this embodiment is not limited to fourbeams600aas two, three, or greater than fourbeams600amay be employed and configured according to the following description to perform similar functions.FIG. 37A illustratesframe600 in a collapsed configuration in whicharms600aare collapsed together to reduce the cross sectional dimensions thereof to dimensions small enough to be passed through the opening (e.g.,225 or227) in the patient. Typically, a delivery tool having a tube orcannula635 is provided through which thecollapsed frame600 can be slidingly passed for delivery of theframe600 into the abdominal cavity.FIG. 37B showsframe600 in an expanded configuration after delivery throughtube635 into the abdominal cavity, where arms orbeams600aspread apart from one another, or “fan out” to from the broad-based platform of anchoringframe600. Beams orarms600amay be pivotally637 connected to one another via pivot joints636 and may be spring-loaded633 so as to spread apart (in the directions of the arrows inFIG. 37B) when a constraining force holding the arms or beams in the compact configuration ofFIG. 37A is removed. Alternatively,arms600amay be configured to unwind like a clock spring when compression forces of the deployment device are removed from holding the frame in a compact configuration. Further alternatively, arms orbeams600amaybe spread apart or radially expanded by plastic deformation to maintain an expanded configuration. For example, once theframe600 has cleared the delivery tooldistal end portion635, arms orbeams600amay spread apart.
• Arms or beams600aare attached to a sheet of tissue ingrowth material602 that folds up, as illustrated (in phantom) inFIG. 37A when beams orarms600aare in the collapsed or contracted configuration, and which are extended into the sheet configuration when arms or beams are extended or fanned out, as illustrated (in phantom) inFIG. 37B. This tissue ingrowth material602 is anchored between the beams orarms600aand the internal abdominal body structure when anchoring frame is anchored thereto, such as in a manner described above with regard toFIGS. 35C-35H. Thus, needles and sutures are driven through each of the arms orbeams600ain a manner like that already described. Alternatively, the tissue ingrowth material may be thetabs150 andtissue ingrowth patches152 extending from anexpandable member10emof adevice10 as described above. In this alternative arrangement,expandable member10emis inserted together with anchoringframe600 and anchored directly to the internal abdominal body structure by suturing through the arms orbeams600aand thetabs150/tissue ingrowth pads152 to fix them directly to the internal abdominal structure.
• In either case, beams orarms600aare attached toingrowth material602,150,152 such as bysnaps600s, or alternatively, by sutures, or other mechanical fixation means. Any of these connections may be supplemented using adhesives, or adhesives alone may be used to establish the connections. Although not required, it may be preferable to establishconnections600son both sides ofneedle openings600nthrough which theneedles610npass when performing the anchoring steps. This is illustrated in the longitudinal sectional views of a portion of an arm orbeam600aandingrowth sheet602,150,152 inFIGS. 37C and 37D, whereFIG. 37C showsneedle610nin a retracted configuration, andFIG. 37D showsneedle610nprotruding through arm orbeam600aandingrowth sheet602,150,152. Anchoringframe600 may also include a central tube or lumen600c(FIG. 37B) that slides overguidewire502 to guide delivery of the assembly into the abdominal cavity and along the structure to whichframe600 is to be anchored. Alternatively, instead of aguidewire502, a scope may be used such that the scope provides visualization and also provides the guiding utility while positioning theframe600. Scope may also provide a semi-rigid guiding member for the delivery. Alternative totube635,tool630 may be provided with achannel650 sufficiently wide to receive the arms orbeams600ain the collapsed configuration. Upon pushing or otherwise slidingframe600 out ofchannel650, arms orbeams600aexpand as already described. Expansion of arms orbeams600amay be limited by travel limits of the pivot joints633, or may be limited wheningrowth material sheet602,150,152 is fully extended, thereby ensuring that the ingrowth material sheet is maintained under tension to ensure it stays fully spread open.
• FIGS. 38A-38B illustratemating engagement members600e,10ethat can be provided as part of any of theframes600 described herein and any of theexpandable members10emdescribed herein, respectively, as well as any of the frames and expandable members described in application Ser. No. (Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2). Further alternatively, and of theframes600 andexpandable members10emmay be provided with any of the interengaging arrangements described in application Ser. No. (Ser.13A,13D,14A-14C,15A-15C and19A-19B and the descriptions thereof.Engagement member600einFIG. 38A provides for multiple track tracking ofexpandable member10em.Engagement member600eincludes a pair ofrails618 on opposite sides of achannel608 within arail618, each of which extend substantially over the length of frame600 (or a beam orarm600athereof).FIG. 38B shows engagingmember10efixed toexpandable member10emwhere the engagingmember10eincludes a pair ofchannels608 on opposites sides of arail618 that extends from achannel608, wherein these features are configured to mated with therails618 andchannel608 ofengagement member600eto be slidably received therein (or thereover, respectively) to interengage theexpandable member10emwith theanchoring frame600. Rail610 ofengagement member10eincludes a central lumen therethrough, so that it can be passed overguidewire502 to guideengagement member10einto alignment withengagement member600eto slidingly engage the components together.
• Engagement member10ecan be provided withlocks620 that automatically lockengagement member10etoengagement member600ethereby securingexpandable member10emin a rotationally and translationally stable position relative to frame600. In the example shown, locks620 are spring loaded and are substantially flush with thechannel608 at distal ends thereof, but have proximal ends that angle into thechannel608. The proximal ends are depressed to be substantially flush with thechannel608 surface asengagement member10e, and particularlychannel608 is being slid overcentral rail618 ofengagement member600e, as the proximal ends of thelocks620 are pressed against therail618 surface. As the component become fully engaged, they are stopped in the direction of relatively sliding to achieve this engagement by stops provided onengagement member600e. Engagement member is locked and thereby prevented from sliding in the opposite direction when the proximal ends oflocks620 expand intomating recesses620rformed inrail618. The arrangement oflocks620 and recesses620rcan be reversed between thecomponents10eand600e, as would be readily apparent to one of ordinary skill in the mechanical arts.FIG. 38C illustratesexpandable member10emin a compacted, low profile configuration for insertion into the abdominal cavity of apatient1, with the central lumen ofrail618 having been threaded overguidewire502 for sliding delivery and guidance of the device into the abdominal cavity. However, this is just a mock-up, asguidewire502 is not shown installed into the abdominal cavity, and that would be performed prior to threadingdevice10emonto theguidewire502. Alternatively, anchoringframe600 may having buoyancy features integrated therein, which can be desirable to reduce the incision size made in the patient for insertion of theanchoring frame600 as well asdevice10, since this can reduce the overall volume of theimplant10 by moving some of the volume (e.g., the volume taken up by abuoyancy member10bm) to theanchoring frame600. Further alternatively, asmaller buoyancy member10bmcan be included indevice10, with a buoyancy member provided in or on anchoringframe600 to provide combined buoyancy effects.
• FIGS. 39A-39C illustrate another embodiment ofmating engagement members600e,10ethat can be provided as part of any of theframes600 described herein and any of theexpandable members10emdescribed herein, respectively, as well as any of the frames and expandable members described in application Ser. No. (Ser. No. not yet assigned, Attorney's Docket No. EXPL-001CIP2). In this arrangement, position adjusting features are provided so that the user/surgeon can select amount a range of locations for positioningexpandable member10emrelative to anchoringframe600. InFIG. 39A, theengagement member10ecomprises a spine orrail618 that is received in a groove orchannel608 in anchoringmember600. However, these components could be reversed, with anchoringframe600 having a spine orrail618 over which a channel or groove, provided inexpandable member10em, can be passed.
• Anadjustable locking mechanism20 in this embodiment includesdetents622 that are configured and dimensioned to be received in locking holes oropenings624. Whendetents622 are positioned through a pair ofopenings624, this prevents further relative sliding betweenrail618 andchannel608. Anactuator626 may be provided on either theanchoring frame600/channel608, whichever includes the engagement member having thedetents622 to, in a first position, temporarily lock the detents in a retracted configuration so that they cannot release and extend throughopenings624, and, when slid to a second position, release the detents, which are biased, such as by spring-loading for example, so that they deploy to pass into a pair ofopenings624 that they are aligned with. If theopenings624 are not aligned with the detents, theexpandable member10emcan be slid in one direction or the other, relative to anchoringframe600 to engage the next adjacent pair ofopenings624.
• Alternatively,openings624 may be beveled or tapered to that ifdetents624 are only partially inserted intoopenings624, as illustrated inFIG. 39C, Then rail can still be slid relative tochannel608, as detents ride in and out of the shallow, beveled portions ofopenings624 asrail618 is slid, since thedetents622 are prevented from passing deeper into holes24 as long as guidewire orrod501 is positioned through alumen623 provided throughrail618. Once the surgeon/user has positionedexpandable member10emis a desired location relative to the anchoring frame, as selected from a multiplicity of possible axial locations along the frame, made possible by the pairs of openings extending longitudinally overrail618, guidewire orrod502 is removed from its location withrail618, allowingdetents622 to slide into locking positions throughopenings624. In this arrangement, detents can be unlocked again by reinserting guidewire orrod502 which pushes the detents back out to the configuration shown inFIG. 39C, allowing expandable member to be repositioned along the length of the engagement mechanism.
• FIGS. 40A-40H illustrate various embodiments ofbuoyancy members10bmthat also function as anchoring frames600. The embodiment ofFIG. 40A includes atubular foam member10bmtwhich may be formed from silicone foam, or some other polymeric foam, for example.Mesh ribbons170, which may be in the form of looped ribbons or single lengths of ribbons, may be tied around thetubular member10bmt, or suture thereto, or both, or fixed using alternative mechanical fixation structures and/or adhesive. Ribbons (e.g., polypropylene or other polymer)170 can be pulled through openings extending from the abdominal cavity of the patient, out through the skin of the patient, to draw buoyancy member/anchoringframe10bm,600 against the internal surface of the abdominal wall, and ribbons can be anchored externally of theabdominal wall127 in any of the manners already discussed previously above. Anexpandable member10emof a device can then be passed overtube10bmtand anchored thereto, wherein thebuoyancy tube10bmtperforms the functions of a buoyancy member discussed above, as well as the functions of ananchoring frame600 discussed above. Alternatively, expandable member may be anchored to tubular buoyancy member/anchoringframe10bm,600 using a docking tether, as described in more detail below.
• FIG. 40B illustrates an embodiment of buoyancy member/anchoringframe10bm,600 provided with acontact surface604 having tissue ingrowth-enhancingmaterial616 provided thereon for enhancing/encouraging tissue ingrowth therein from the internal structure of the abdominal cavity to whichcontact surface604 is anchored to (e.g., internal surface of abdominal wall127).FIG. 40C shows an end view of the buoyancy member/anchoringframe10bm,600 ofFIG. 40B.FIG. 40D illustratesribbon loops170 attached totubular member10bmtand extending throughbacking surface604 and tissue ingrowth-enhancingmaterial616 in position to be pulled out of the patient to draw buoyancy member/anchoringframe10bm,600 up against an internal body structure to be anchored there.
• FIG. 40E is an illustration of a patient showing one example of whereribbons170 can be pulled through theskin125 of the patient to draw the buoyancy member/anchoringframe10bm,600 up against the inner surface of the abdominal wall. The X's indicate locations where punctures can be made and a hooked tool or graspers can be inserted therethrough to retrieveribbons170 to pull them out of thepatient1, draw the buoyancy member/anchoringframe10bm,600 up against the inner surface of the abdominal wall, and lockribbons170 down against an external surface of the abdominal wall/fascia. It is noted that optionally, at least one of the ribbons can be drawn though an intercostal space, as shown inFIG. 40E.
• FIGS. 40F-40G illustrate features for anchoring theexpandable member10emto the buoyancy member/anchoringframe10bm,600 according to one method embodiment. In this embodiment,buoyancy tube10bmtis provided with an annular opening therethrough. After anchoring the buoyancy member/anchoringframe10bm,600 to an internal abdominal structure, such as the abdominal wall, in a manner as described above, aguidewire502 or snarecatheter502 can be inserted through the lumen oftube10bmtas shown in FIG.40F. Theexpandable member10emofdevice10 can be provided with adocking tether59d, such as a braided mesh polymer tether, woven polymer tether or ribbon, for example. Dockingtether59dcan be fixed to a superior portion ofexpandable member10emand has a free opposite end having adocking connector59c. An inferior portion ofexpandable member10emis provided with amating connector59mthat is mateable withdocking connector59cto form a locked connection. In the example shown,docking connector59ccomprises a male luer connector andmating connector59mcomprises a female luer connector. However, these could be reversed. Further alternatively, other types of mating, mechanically connectable members could be substituted.
• After placingexpandable member10eminto the abdominal cavity (in a non-expanded configuration),guidewire502 or snarecatheter502sis used to capture the free, proximal end of dockingtether59d. The captured free end is then into the distal end opening oftubular member10bmt, through the annular space intube10bmtand out of the proximal opening.Connector59cis then connected tomating connector59m, thereby locking the free end of dockingtether59dtoexpandable member10emand anchoringexpandable member10emto buoyancy member/anchoringframe10bm,600 as illustrated inFIG. 40H.
• On advantage of using a dual-function buoyancy member/anchoringframe10bm,600 is that it is a low profile system, since thebuoyancy member10bmandexpandable member10emdo not require simultaneous insertion into the abdominal cavity. Further, a dual-function buoyancy member/anchoringframe10bm,600 is very lightweight and therefore may reduce potential complications during the tissue ingrowth period required for tissue for tissue from the anchored-to structure to grow into the anchoring frame. This can be particularly advantageous in situations where buoyancy member/anchoringframe10bm,600 is anchored by itself and allowed a tissue ingrowth period before fixing an expandable member thereto, or in situations where theexpandable member10emis initially fixed to buoyancy member/anchoringframe10bm,600, but is not inflated or only partially inflated with liquid during the tissue ingrowth period.
• FIG. 41 shows examples of implant markers and sensors that may be included ondevice10. Any combination of implant markers and sensors shown, including a single marker or sensor, up to and including all markers and sensors shown, may be included on any of the devices described herein, in the locations shown (or corresponding locations for different embodiments of devices10). Additionally, these features are not limited to the locations shown, but can be included at other locations, such as, but not limited to: anywhere along one ormore conduits12, attachment tab(s)150, positioning loop(s)170, any locations on anchoringframe600 or corresponding components thereof, etc.
• Markers420 may be provided at various locations ondevice10 that are trans-abdominally detectable, for example, using fluoroscopy (radiopaque markers), ultrasound (ultrasonically detectable markers), three-dimensional navigation (magnetic or RF sensors) for indirect visualization/tracking ofdevice10 during the implantation procedure, as well as afterdevice10 has been implanted and the procedure has been completed. These markers can be present on the surface ofdevice10 or may be embedded beneath one or more layers of material, or molded within a layer, for example. Additionally, or alternatively,visual indicators422, such as text, arrows or other graphical markings or visually detectable indicators can be provided for direct viewing by laparoscopy, for example.Indicators422 may also be provided with contrasting colors to make them easier to locate relative to the portion ofdevice10 that they are located on.
• The material(s) making up all or a portion ofdevice10 may be doped with radiopaque material to facilitate identification thereof by indirect viewing such as fluoroscopy or other X-ray.Markers420 and/orindicators422 may also be used to assess function. For example, themarkers420 identified by “S” and “I” inFIG. 41 may be viewed and a distance therebetween measured to assess the amount of expansion/filling ofexpandable member10emthat has occurred.Markers420 can additionally or alternatively be used as sensors to provide feedback to measure relative position ofdevice10, pressure withinexpandable member10em, motility ofdevice10, volume occupied bydevice10 orexpandable member10em, etc.Markers420 may be detectable trans-abdominally using known sensing modalities such as magnetic, RF, X-ray, ultrasound or auditory signals.Markers420 may also be configured to emit/transmit RF, ultrasound or auditory signals, for example. Thus, marker(s)420 and/or indicator(s)422 can be used to give the surgeon or other person feedback during, as well as after completion of the implantation procedure, as to location ofdevice10 and/or functionality thereof.
• As one example of use ofmarkers420 for three-dimensional navigation of the delivery and placement ofdevice10 during an implantation procedure, a pre-existing “map” of the internal structures of apatient1 may be provided in the way of a CT scan, for example, so that a surgeon can study this map prior to the procedure and identify the bony structures around the abdominal cavity, to be used as landmarks during the procedure to help in navigating/directingdevice10 and associated tools to one or more desired target locations in the surgical site. Although soft tissues will be mobile, the surgeon can identify target locations relative to the bony landmarks.
• At the beginning of the procedure, typically, prior to making an incision, the actual bony structures of the patient1 (as visualized under fluoroscopy, for example, or palpation to identify pre-determined registration points) are registered to match the locations of the same structures on the pre-existing map, which can be displayed on a monitor, for example. During the procedure, themarkers420, whether detected by fluoroscopy, magnetic detection, RF detection, ultrasound detection, etc. are displayed on the monitor overlaid on the pre-existing map to which the bony structures of thepatient1 have been registered. Accordingly, the surgeon/user can view in real time, a three dimensional image of the location ofmarkers420 relative to the landmark bony structures, to guide the surgeon/user to deliverdevice10 along a desired pathway and place andimplant device10 in the desired target location.
• Not only candevice10 be navigated in this manner, but any other instruments or devices inserted into thepatient1 during the procedure, can also be navigated in similar fashion. For example, insertion and placement ofguidewire502, prior to insertion of device, can be guided and navigated by provided a distal tip or distal end portion of guidewire with asensor420. Other tools and devices can be navigated similarly.
• Sensors420 may be passive and/or active. For example,sensors420 can simply be magnets or radiopaque markings, which are passive sensors that are detected by instrumentation outside of the body of the patient. Alternatively,sensors420 may be active, such as sensors that transmit RF signals, or other electrical signals, for example. Further alternatively,sensors420 may have both passive and active functions. A sensor may be “pinged” by instrumentation outside of the patient's body and reflected waves returned from the sensor being pinged can be triangulated by feedback from external sensors to determine the location ofsensor420.Sensor420 may include an antenna and processor that can instruct it to emit a signal when a particular instruction has been received by the antenna. Any of the sensing and/or navigation methods described above can optionally also reference thestomach120, such as by fluoroscopy or X-ray when radiopaque contrast fluid is inputted into the stomach.
• One ormore sensors420 may also be used for the performance of one or more procedural steps robotically. As one non-limiting example of this,FIG. 42 illustrates a procedural step for anchoringanchoring frame600 to an internal surface ofabdominal wall127 usingribbons170. Arobotic arm700 having acontrollable module702 that is controllable to move a working tool704 (in this case, a hooked needle) in three dimensions is provided over thatpatient1.Module702 is first moved in two dimensions parallel to the skin of the patient (i.e., in the dimensions of the arrows shown and the dimension into and out of the page) to alignsensor706 with asensor420 on anchoringframe600 that is aligned with one of theribbons170. Once this alignment has been confirmed,tool704 is then robotically driven into thepatient1 to pierce theskin125 and to a depth to engageloop170 with the hooked portion of theneedle704.Tool704 is then retracted back out of the patient to pull a portion of theribbon170 out of theskin125. Tensioning of theribbon170 and anchoring it to an external surface of the abdominal wall/fascia127 can optionally also be performed robotically. It is noted that this is only an example of a robotic procedural step that can be performed, as virtually any and all procedural steps described herein can be performed robotically, using the sensing and control techniques described herein.
• FIG. 43 illustrates ahandheld device720 configured to communicate with one ormore sensors420 located internally of the patient, such as on device10 (and/or anchoringframe600,conduit12, etc.) Handheld device may be powered by apower cord722 that plugs into an electrical outlet, or may be battery powered, and thus more portable.Device720 may be operated by a treating physician, or by the patient himself, for example. In the example shown,device10 includes twoexpandable members10em₁and10em₂, each provided with apressure sensor420 configured to receive a wirelessly transmitted signal fromhandheld device720, and, in response thereto, transmit a wireless signal (e.g., RF signal or the like) to handheld device to indicate the current pressure reading. Other sensing capabilities that may be provided include, but are not limited to: sensing of stomach motility via electrical signals or motion sensors or stretch detectors; pressure sensing; temperature sensing; oxygenation sensing; sensing of grehlin or other hunger or satiety markers. Upon reading the signals fromsensors420,device720 displays the sensed pressures ondisplay724, for example. These readings can provide useful information to thepatient1 and/or physician as to whether an expandable member(s) has sufficient pressure or is over or under inflated, for example and thus whether a pressure adjustment needs to be made. Additionally, these readings can identify a leak in the device and alert the user thereto, without the need for initial checking by X-ray or more invasive means.Device720 may also be connectable to the Internet, for example, by wireless communication, and may be programmed to email a physician when used by thepatient1 and when one or more readings is not within expected ranges, thereby alerting the physician that the patient needs to be seen in the physician's office to correct a problem with thedevice10.
• FIG. 44 illustrates an example where a surface ofexpandable member10emis provided withsensors420 comprising electrodes that can be used to deliver pacing signals to the stomach from a subcutaneously placed pacer/stimulator428 that communicates viawires429 or wirelessly with electrodes ofsensors422.Sensors422 may also function as pressure sensors and send signals representative of pressure readings to pacer/stimulator428. Accordingly, when signals are received that correspond to pressures greater than a predetermined pressure level (e.g., indicative of food having been inputted to the stomach120) this can initiate a pacing program in the pacer/stimulator to send coordinated stimulation signals to theelectrodes420 to increase or decrease motility caused by contraction of stomach muscles resulting from the pacing signals applied by theelectrodes420.
• FIG. 45 illustrates another embodiment ofdevice10 in whichwiring429 extends throughconduit12 to be connected to pacer/stimulator428. In this case, pacer/stimulator428 may be incorporated intoaccess member80 or subcutaneously implantedadjacent access member80, for example. Althoughdevice10 is shown to include twoexpandable members10em₁,10em₂, this arrangement may be applied equally as well to devices having a singleexpandable member10em(with or withoutbuoyancy member10bm) or more than two expandable members. Further alternatively,sensors420 in eitherFIG. 44 orFIG. 45 may not provide pressure sensing feedback, but may be only electrodes for applying the pacing signals. In such case, pacer/stimulator428 may be controlled manually by the user or physician, either wirelessly, or by plugging a controller into a socket provided inaccess member80, or on theskin125 of the patient, for example, to apply pacing signals to theelectrodes420.
• While the present invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process step or steps, to the objective, spirit and scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto.

Claims (5)

1-95. (canceled)

96. A method of treating a patient, said method comprising:

passing a device into the abdominal cavity of the patient;

anchoring at least a portion of the device, relative to at least one structure in the abdominal cavity; and

occupying a space in the abdominal cavity with the device to substantially restrict expansion of the fundus of the stomach, and restraining the stomach to a shape resembling a tube, but wherein at least a portion of the antrum is left unrestrained.

97. The method ofclaim 96, wherein a small pouch is also left unrestrained at a superior end portion of the stomach.

98. A method of treating a patient, said method comprising:

passing a device into the abdominal cavity of the patient;

anchoring at least a portion of the device, relative to at least one structure in the abdominal cavity; and

occupying a space in the abdominal cavity with the device to substantially restrict expansion of the fundus of the stomach, and restraining the stomach to a shape resembling a tube, but wherein a small pouch is left unrestrained at a superior end portion of the stomach.

99-171. (canceled)

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