WO2017136840A1

WO2017136840A1 - Method of fabrication for devices for deploying and releasing a temporary implant within the body

Info

Publication number: WO2017136840A1
Application number: PCT/US2017/016735
Authority: WO
Inventors: Matthew S. Lake; Samuel Moss; Bruce A. Horwitz
Original assignee: Allurion Technologies, Inc.
Priority date: 2016-02-05
Filing date: 2017-02-06
Publication date: 2017-08-10
Also published as: DE112017000675T5; GB201813402D0; GB2562954A

Abstract

Methods of manufacturing expandable devices. The expandable devices can include medical devices as described herein as well as devices used in non-medical applications.

Description

METHOD OF FABRICATION FOR DEVICES FOR DEPLOYING AND RELEASING A TEMPORARY IMPLANT WITHIN THE BODY

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a non-provisional of U.S. Provisional application No.

62/291,891 filed February 5, 2016, entitled METHOD OF FABRICATION FOR DEVICES FOR DEPLOYING AND RELEASING A TEMPORARY IMPLANT WITHIN THE BODY, and U.S. Provisional application No. 62/291 ,904 filed February 5, 2016, entitled METHOD OF

FABRICATION FOR DEVICES FOR DEPLOYING AND RELEASING A TEMPORARY IMPLANT WITHIN THE BODY, the entirety of both of which are herein incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention generally relates to the field of devices that temporarily occlude spaces within the body to provide a therapeutic effect.

[0003] According to 2010 World Health Organization data, 198 million Americans over the age of 15 are above target weight. Of these individuals, 89 million are considered overweight (25<Body Mass Index<30) and 109 million are considered obese (Body Mass Index >30). Worldwide, more than 1.4 billion adults age 20 and over are overweight, and 500 million are obese. Obesity places patients at increased risk of numerous, potentially disabling conditions including type 2 diabetes, heart disease, stroke, gallbladder disease, and musculoskeletal disorders. Compared with healthy weight adults, obese adults are more than three times as likely to have been diagnosed with diabetes or high blood pressure. In the United States it is estimated that one in five cancer-related deaths may be attributable to obesity in female non-smokers and one in seven among male non- smokers (>= 50 years of age). On average, men and women who were obese at age 40 live 5.8 and 7.1 fewer years, respectively, than their healthy weight peers.

[0004] Gastric bypass surgery is the current gold standard treatment for patients with a body mass index ("BMI") of greater than 40. Gastric bypass surgery is also an option for those with a BMI between 35-39 with obesity-related co-morbidities. While gastric bypass surgery results in decreased food consumption and weight loss for a majority of recipients, it requires life-altering, permanent anatomic modifications to the gastrointestinal tract and can result in severe complications. Gastric bypass and related surgical procedures are also expensive, costing about $22,500 (by laparoseopy). For these reasons, only about 250,000 surgical obesity procedures are performed per year in the US.

[0005] For the vast majority of the overweight and obese population for whom surgical obesity procedures are not appropriate, few efficacious and affordable interventions are currently available. Diet and exercise remain the front line approaches to obesity, however this approach has at best slowed the growth of the epidemic. To date, drug therapies have dose limiting side effects or have lacked meaningful long term efficacy.

[0006] One less-invasive intervention that has begun to gain popularity is an intragastric balloon. Intragastric balloons can be placed endoscopically or positioned using other methods and generally must be removed endoscopically or rely on the body's natural digestive processes for removal.

[0007] The method of fabrication discussed herein are intended to provide an efficient method of fabrication for balloon devices for the treatment for obesity.

SUMMARY OF THE INVENTION

[0008] The present invention relates to devices and methods for occupying a space within a patient's body. In particular, the devices and methods can be used within a gastric space. However, the devices and methods can be used in any part of the body. In greater particularity the present invention relates to fluid valves for use in these space occupying devices.

[0009] The devices described herein can also be used for delivery of drugs, pharmaceuticals, or other agents where such items can be delivered on a skin of the device, within a reservoir, in a filler of the device, or anywhere on the device. Such agents can be released over time.

[0010] The present disclosure includes medical devices for use with a liquid filler material and for occupying a space within the patient^'s body. In one example such a medical device includes a liquid impermeable surface material forming a device body having an interior reservoir, the device body having a deployment profile and expandable to an active profile upon receiving the liquid filler material within the interior reservoir; a liquid tunnel having at least one wall and defining an elongated passage, at least a portion of the liquid tunnel extending within the interior reservoir, and where the at least one wall of the liquid tunnel is pre-disposed to obstruct the elongated passage to prevent fluid flow therethrough; a fluid conduit having a distal portion located within the elongated passage of the liquid tunnel to create a fluid path through the elongated passage for delivery of the fluid into the interior reservoir, and where the fluid conduit is removable from the liquid tunnel, such that upon removal of the fluid conduit, the at least one wall of the liquid tunnel obstructs the elongated passage to prevent fluid therethrough the elongated passage; and a release channel formed by an elongated section of liquid impermeable material, where the elongated section of liquid impermeable material is inverted into the interior reservoir and temporarily restrained therein, wherein, when temporarily restrained, the release channel is closed to prevent liquid transfer to or from the patient's body..

[0011] The present disclosure includes methods of manufacturing expandable devices. The expandable devices can include medical devices as described herein as well as devices used in non-medical applications.

[0012] In one example, the present disclosure includes a method of providing a multi-l ayer thin film of polymeric material, the multi-layer thin film of polymeric of material comprising a thin film backing layer and a thin film working layer and, wherein the first thin film backing layer is disposed on a first side of the thin film working layer; positioning the multi-layer thin film on an open frame and heating the multi-layer thin film; forming the multi-layer thin film into a device section having a predetermined shape using differential gaseous pressure to conform the multilayer thin film to a mold, the device section having an inner surface and an outer surface, one backing layer comprising the outer surface, the predetermined shape having a flat flange region; disposing a first device section together with a second device section such that the working layers of the first and second device section are juxtaposed with the flange region of the first device section being in alignment with the flange region of the second device; creating an access hold in at least one of said two device sections; joining the flange regions of the device sections to form a fluid tight seam around the entire flange; trimming an excess material from around the flange region; and inverting the device though the access hole.

[0013] The method can further comprise forming the film into a device section comprises the step of forming a convex and a concave device section.

[0014] In an additional variation, the step of forming a convex and a concave device section comprises using a dual mold to produce the convex and the concave device sections

simultaneously. Moreover, if a second thin film backing layer can be disposed on a second side of the thin film working layer. In such a case, the method can further comprise removing the second backing layer before heating the muli-layer thin film. [0015] In an additional variation, the method further comprises cutting an access hole through at least one device section, the hole disposed to avoid intersection with the flange region.

[0016] The method can also include exposing one side of the working layer by removing a backing layer.

[0017] In an additional example, the method further comprises disposing an additional device subcomponent between the aligned working layers of the first device section together and the second device section.

[0018] Joining of the flange regions of the device sections can include any process known by those skilled in the art. Such processes can include joining by thermal, mechanical, or chemical joining.

[0019] The above and other features of the invention including various novel details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invent ion may be employed i various and numerous embodiments without departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The foregoing and other objects, features and advantages of the methods, devices, and systems described herein will become apparent from the following description in conjunction with the accompanying drawings, in which reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale; emphasis has instead been placed upon illustrating the principles of the invention. Of the drawings:

[0021] FIG. 1A, illustrates an example of a gastric device assembly prior to assuming an active profile.

[0022] FIGS. IB and 1C show partial cutaway views of examples of device assemblies for use in occupying space within a body.

[0023] FIG. ID illustrates the variation of the device shown in FIG. 1A as the device assembly assumes an active profile. [0024] FIG. IE shows a device assembly after it is inflated, expanded, or otherwise transitioned to achieve a desired active profile.

[0025] FIG. 1 F illustrates a state of a device assembly after a physician, patient, or other caregiver desires to initiate release the device assembly from the body.

[0026] FIG. 2 shows a device assembly or construct in a hydrated or active profile whose outer "skin" defines a material reservoir or pocket.

[0027] FIG. 3 illustrates a variation of a fluid transfer member also having a sea I able fluid path for use with the device assemblies described herein.

[0028] FIG. 4 shows a schematic perspective view of a variation of a tunnel valve being installed during fabrication of the device assembly.

[0029] FIG. 5 illustrates a partial view of a variation of an inverted section of a skin of a device assembly closed by a release material.

[0030] FIG. 6 illustrates a partial view of the interior of a device assembly comprising an inverted section of the skin further having an interior energy storage element that assists in opening of the device in response to an exogenous trigger.

[0031] FIG. 7 provides a schematic illustration of another example of a device assembly having a release material located on a surface of the skin.

[0032] FIG. 8 shows an additional variation of a portion of a device assembly that provides a control over the fluid permeable path through otherwise impermeable material surface.

[0033] Figs. 9A and 9B an example of a valve driven by expansion of filler material within a reservoir of the device assembly.

[0034] FIGS. 9C and 9D show another variation of the valve of FIG. 9 A comprising catheter passage holes.

[0035] FIG. 9E shows a variation of a valve comprising dem i l unar hybrid flow control layers in which the impermeable region and permeable region are semicircular.

[0036] FIG. 10A illustrates a variation of a tunnel valve as discussed above that forms a seal able fluid path preventing material from escaping from the interior of the device.

[0037] FIG. 1 0B I shows a schematic cross sectional view of tunnel taken along line 1 0B- 1 0B of FIG. 10A . [0038] FIGS. 10B2 and 10B3 show schematic cross sectional views of two variations of the tunnel valve of FIG. 10A

[0039] FIG. IOC shows the tunnel in its closed configuration after the conduit is removed.

[0040] FIGS. 10D to 10G show a conduit that is mechanically coupled to a tunnel valve.

[0041] FIG. 10H1 to 10H3 show a schematic cross-sectional view of a tunnel valve including a packing substance between layers of the tunnel valve and a conduit taken along line 10H-10H of FIG. 10B 1

[0042] FIGS. 101 and 10J shows the use of a spring loaded closure device that aids in sealing of a tunnel valve.

[0043] FIG. 14 A is a plan view of a variation of the device in mid-fabrication in which the two layers of the tunnel valve are fabricated as part of the upper and lower skins of the device.

[0044] FIG. 14B is an exploded cross-sectional view of the device of FIG 14A taken along line 14B-14B.

[0045] FIG. 15 illustrates a co-extruded material comprising a working layer and two backing layers.

[0046] FIG. 16 illustrates the optional removal of one of the two backing layers from the working layer in the material of FIG 15 in process.

[0047] FIG. 17 A is a cut-away perspective view of an exemplary thermoforming mold

[0048] FIGS. 17B 1 and 17B2 are schematic cross-section illustrations of an exemplary thermoforming mold with formed polymeric material in place.

[0049] FIGS. 17C is a schematic cross-section illustration of an exemplary thermoforming mold for making convex and concave device sections simultaneously.

[0050] FIG. 1 8 A shows a schematic cross-section illustration of two device sections nested in preparation for joining by means of RF welding.

[0051] FIG. 18B shows a schematic cross-section illustration of nested device sections manufactured with the mold of FIG. 17C.

[0052] FIGS. 19A and 19B illustrate various thermoforming manufacturing processes where heat is applied to a polymeric sheet. [0053] FIG. 20A is a schematic plan view of optional subcomponents disposed between two working layers prior to the joining step.

[0054] FIG. 20 B is a schematic exploded side view of the optional subcomponents disposed between two working layers prior to the joining step.

DETAILED DESCRIPTION OF THE INVENTION

[0055] The following illustrations are examples of the invention described herein. It is contemplated that combinations of aspects of specific embodiments or combinations of the specific embodiments themselves are within the scope of this disclosure. While the methods, devices, and systems described herein are discussed as being used in the stomach or gastric space, the devices, methods, and systems of the present disclosure can be can be used in other parts of the body where temporary occlusion of a space might be required or beneficial. The present disclosure is related to commonly assigned to US Publication No. 2011/0295299 filed March 2, 201 1 , the entirety of which is incorporated by reference.

[0056] FIG. lA, illustrates an example of a gastric device assembly 100. In this example, the gastric device assembly or construct 100 can reside in a stomach (typically of a mammal ) for an extended period of time. One benefit of such a device is that, when part ial ly or fully deployed, the construct 100 occupies volume within the stomach to produce a therapeutic effect, e.g., to stimulate the sensation of satiety, and resists passage from the body by normal body function. As illustrated below the construct generally comprises three states: a pre -deployment configuration (FIG. 1A); a deployed or active configuration (FIG. ID, IE); and a release configuration

(FIG. IF). As noted above, the device can also be used for therapeutic benefits that do not involve occupying volume (e.g., drug delivery, creation of a cavity by separating adjacent tissue, etc.).

[0057] FIG. 1 A illustrates a variation of the device 100 after placement within a stomach 2. As described herein, the initial configuration of the device 100 includes a compact state that allows placement within the body. The device can be in a pill-type configuration or any other shape that permits swallowing. Alternatively, the device 100 can be positioned by the use of a scope type device, catheter, or other medical positioning device.

[0058] For a device used in the digestive tract/gastric space, the device assembly 100 can be positioned within the body either by natural ingestion or the use of a delivery system (such as a catheter, endoscope, or other medical device). The delivery system can optionally comprise an oral dosage form, not illustrated, which facilitates the ingestion of a relatively large object. In other embodiments the system comprises a tether that allows manipulation or control of the placed construct from outside of the body. The assembly 100 can also be placed in the stomach by more invasive surgical or endoscopic procedures.

[0059] In FIG. 1A, the device 100 is shown immediately after being deployed within the stomach 2 and is ready to be activated. As noted herein, the device 100 can be deployed in the configuration shown. Alternatively, the device can be contained within a capsule or pi II -type casing that allows for swallowing by a patient. Once swallowed, the casing will readily dissolve or break down resulting in the configuration shown. Once in place in the stomach, the assembly 100 begins to expand in order to occupy volume space within the body. Expansion can occur vi manual inflation, including hydration or other activation of a filler material (as shown optionally using a catheter, inflation tube or other delivery system), via absorption of body fluids, via remote actuation of a substance already located within the device assembly, and/or delivering of a fluid into the assembly, where the fluid itself causes expansion. Variations of the device also incl de a combination of such expansion means.

[0060] The variation shown in FIG. 1 A includes a member 110 that extends from the device 100 to outside of the patient. In this variation shown, the member 1 10 comprises a fluid transport member that is fluidly coupled to an interior of the device 100 allowing for the delivery of substances and or fluids within the device 100. FIG. 1 A shows an exemplary fluid source 90 coupleable to a variation of a fluid transport member 110 such that the delivery of fluid causes a filler material 108 within the device to expand. In the illustrated example, the fluid transport member comprises a conduit. However, alternate variations of the devices described herein in lude fluid transport members that reside within the patient's body. Alternate variations of the device 100 also include members 110 that function as delivery or positioning systems to ensure proper placement of the device 100 within the body. Such delivery systems may or may not be fluidly coupled with an interior of the device. In variations discussed below, the device can include one or more fluid transport members that remain within the body but still convey fluid into the device 100 to allow the device to assume an active profile.

[0061] FIG. IB shows one a partial cutaway view of an example of a device assembly 100 for use in occupying space within a body. In this variation, the device assembly 100 includes a material surface or skin 102 that forms a reservoir or pocket 104 capable of retaining a variety of substances, including but not limited to fluids, solid substances, semi-solid substances, etc. In the illustrated variation, the reservoir 104 holds a filler material 108 such as dehydrated hydrogel granules that can swell in size upon the addition of a fluid. However, any number of substances can be contained within the reservoir 104. Alternate variations of the device and/or method include assemblies that do not include a filler material; rather a filler material can be deposited within the reservoir 104 once the assembly is deployed. Alternatively, or in combination, the reservoir can be filled with a gas, liquid or other gel type substance.

[0062] In other variations, the device assembly 100 can include an empty reservoir that can be deployed into the body and subsequently filled with a filler material or other substance. For example, such variations can include a liquid filler material that is delivered to the reservoir through a conduit. The volume of liquid required to expand the device into a desired active profile can pre-determined. In some variations, the volume can be determined by measuring the back pressure in the conduit or pressure within the reservoir using any number of pressure detecting elements.

[0063] FIG. 1 B also illustrates a variation of a sealable fluid path 1 12 coupled to and or forming part of the fluid transfer member. In this example, the sealable fluid path 112 extends outside of the perimeter of the skin 102 of the device 100. Additional variations of the device 100 can include significantly shortened sealable fluid paths 1 12. In yet additional variations, the device assembly 100 can omit the sealable fluid path 1 12.

[0064] As noted herein, the skin 102 includes a release material 106 coupled thereto, where the release material 106 allows for initiating release of the assembly 100 from the body shortly after degradation, activation, or breakdown of the release material. Once the device assembly 100 is in the active profile, it can remain in the active profile for a pre-determined amount of time or until the patient experiences a desired therapeutic effect. To initiate release of the device assembly 100 from the body, an exogenous material, substance or stimulus is administered to the patient. The substance can comprise a fluid or other activating agent having properties that either directly or indirectly act on the release material to disrupt the barrier and allow the contents of the reservoir to be exposed to the body. For example, the exogenous substance can comprise a heated fluid that melts the release material. Alternatively, the exogenous material can change a temperature and/or an acidity of fluids in the stomach such that the enhanced properties of the fluids begin to act, either directly or indirectly, upon the release materials. In additional variations, the release material can comprise a material or materials that effectively form a barrier as discussed herein and are separated or disengaged by the use of an exogenous stimuli (e.g., a magnetic field, ultrasound, IR heating, coherent light, electromagnetic signals, microwave field, etc.). [0065] FIG. IB also illustrates a variation where the release material 106 is in the form that approximates shape and/or size of the casing used to deliver the device 100 (in this example the release material 106 is in a pill shape). One benefit of such a configuration is that the release material 106 can be positioned within the casing without excessive folding or bending.

[0066] FIG. 1 C illustrates a sectional view of another variation of a device assembly 100. In this variation, the release material 106 binds or otherwise joins edges of the skin from within the reservoir 104. Such a configuration protects the release material 106 from the local environment of the body (e.g., fluids within the stomach or digestive tract). The release material can still be activated and/or degraded by the addition of the exogenous material to the body as described herein. However, positioning of the release material within the reservoir permits the skin 102 to serve as an additional layer of protection to prevent inadvertent release of the device assembly 100. The release material 106 can comprise a layer that binds edges of the skin together.

[0067] FIG. 1C also illustrates a variation of a sealable fluid path 1 1 2. In this example, the sealable fluid path 112 does not extend outside of the perimeter of the skin 102. Additional variations of the device 100 can include significantly shortened sealable fluid paths 112. In yet additional variations, the device assembly 100 can omit the sealable fluid path 1 1 2.

[0068] FIG. 1 1) illustrates the variation of the device 100 shown in FIG. 1 A as the device assembly 100 assumes an active profile. An active profile includes any profile apart from a deployment state and where the profile allows the device to perform the intended effect of occupying volume or space within the body to produce a therapeutic effect. In the illustrated example, a physician or other medical practitioner delivers fluid via the fluid transport member 1 10, comprising a conduit 1 14 in this variation, and into the reservoir 104 causing a filler material 108 to swell. As noted herein, other variat ions incl ude device assemblies without filler material where the conduit 1 14 simply delivers fluid and or other substances that allow the device assembly to achieve an active profile.

[0069] When using a conduit 1 14 that extends outside of the body, a physician can del iver a hydrating liquid, such as water or distilled water through the conduit 114. Generally, a predetermined volume of liquid can be manually or mechanically pumped into the exterior end of the conduit wherein the volume of liquid is pre -determined based on a particular size of the device assembly or based on a desired active state. In some variations, the volume of liquid can also depend on the length of conduit. [0070] The conduit I 14 can be used to transfer a substance or into the reservoir 104 of the device. In the illustrated variation, the conduit 1 14 transfers fluid from outside of the patient^'s body into the reservoir 104 after deployment of device assembly 100 within the body. Alternatively, or in combination, a fluid transfer member can comprise a wick type device that transfers liquids or other fluids from within the body to the reservoir.

[0071 ] FIG. 1 E shows the device assembly 100 after it is inflated, expanded, or otherwise transitioned to achieve a desired active profile. A physician can monitor the profile of the device assembly 100 either using a scope positioned within the stomach (not shown) or non-invasive imaging such as ultrasound or a radiographic imaging. Alternatively, or in combination, the active profile can be achieved after a pre -determined volume of fluid, liquid and/or gas is delivered to the reservoir 104. Furthermore, variations of the device can include one or more markers (such as radiopaque markers) 1 16 allowing a physician to determine orientation and or size of the device assembly 100.

[0072] As noted above, this particular variation of the assembly 100 includes a conduit 114 that is coupled to the skin 102 through the fluid path 112 and extends into the reservoir 104.

Alternatively, a conduit 114 can be directly coupled to the skin. When the device assembly 100 achieves the active state the conduit 114 can be pulled from the device assembly 100. For those variations that employ a scalable fluid path 112, withdrawal of the conduit 114 causes the sea I able fluid path 112 to collapse or be compressed thereby preventing the contents of the reservoir 104 from escaping from the device assembly 100. Alternatively, or in combination, the scalable fluid path 112 located within the reservoir 104 can be sealed due to the increased pressure within the reservoir. In other words, the same pressure within the reservoir 104 that causes expansion of the device 100 also causes the scalable fluid path 112 to close, compress or otherwise reduce in diameter to a sufficient degree that material is unable to escape from the reservoir through the scal ble fluid path 1 12.

[0073] In certain variations, the conduit 1 14 is held in place in the scalable fluid path 112 by friction alone. Withdrawal of conduit occurs by pulling on the conduit in a direction away from the device 100. During the initial stages of this withdrawal activity the expanded device 100 generally moves upwardly with the conduit in the stomach, until the expanded device 100 reaches the esophageal sphincter. With the device assembly restrained from further upward movement by the sphincter, the conduit 114 may then be withdrawn from the fluid path and from the patient by additional pulling force. [0074] Upon withdrawal of conduit 114 the fluid path effectively seals, as described herein, and prevents migratio of fluids or other substances into and out of the reservoir. In certain variations the fluid path seals on its own after removal of a conduit or other member located therein. In additional variations, hydrostatic pressure and/or pressure caused by the expanded filler acting along the length of the fluid path can aid in sealing of the fluid path.

[0075] FIG. 1 F illustrates a state of the device assembly 100 after a physician or the patient desires to initiate release the device assembly 100 from the body. As discussed above, an exogenous material 120 is delivered into the stomach (or other portion of the body as applicable). As the exogenous material 120 (or exogenously activated body fluids) engage the release material 106, the release material reacts to the conditions created by the exogenous material and begins to degrade, melt, break down, or otherwise become unstable such that the physical barrier of the skin 102 becomes compromised. As noted above, additional variations of the devices can be used with an exogenous stimulus in place of or in addition to an exogenous material. For example, the exogenous substance can directly act upon the release material such as providing a substance at an elevated temperature and/or PH. level that causes disruption of the release material to allow the filler material to interact with the fluids in the stomach and/or to pass from reservoir into the stomach. Alternatively, the exogenous material can interact with fluids within the body to directly or indirectly activate and/or degrade the release material.

[0076] In alternate variations, the release material, or additional areas on the skin degrade or become unstable due to the passage of time in the normal gastric environment. In such cases, the additional areas can serve as a safety mechanism to ensure release of the device alter a predetermined period of time. For example, in the variation shown in FIG. 1 F, one of the areas of release material 106 can be responsive to exogenous stimulus or exogenous materials while the other release material 106 can break down over time. Alternatively, or in combination, as shown in FIG. IF an exogenous st imul i can be used in combinat ion with the exogenous material 120 to cause disruption of the release material. In another variation, the exogenous stimuli 130 can be used to act directly on the release material 106 (without any exogenous material ) to cause disruption of the release material 106 and to begin the process of releasing the device assembly 100 from the patient.

[0077] FIG. IF illustrates the filler material 108 escaping from the reservoir 104 as the device assembly 100 decreases from its active profile to allow for passage of the skin 102 and filler material 108 from the body. In certain variations, the consistency of the escaping filler material 108 is similar to or closely approximates the consistency of a food bolus. The matching of the consistency of the filler material to naturally occurring particles that travels within the body ease the passage of the filler material 108 through the remainder of the digestive tract. In certain situations, the instability or degradation of the release material 106 allows bodily fluids to mi with the content of the reservoir 104. which liquefies the filler material and expedites reduction of the device assembly 100 from an active profile or state. Although not illustrated, as the device assembly reduces in profile, the peristaltic movement of the muscles in the digestive tract works to extrude materials out of the device 100, allowing for the passage of the skin 102 of the device 100 through the digestive tract until it is ultimately excreted from the body. Certain variations of the device assembly can be made to have a soft, lubricious and/or malleable configuration to aid in passing through the gastrointestinal tract.

[0078] FIGS. 1 A to I F are intended to illustrate variations of devices and methods for occupying space within a patient's body, especially those devices for use within a gastric space. However, the principles described above can be used with any number of variations of the device as described below. As noted herein, combinations of different variations of devices, as well as the

combinations of aspects of such variations are considered to be within the scope of this disclosure where such combinations do not contradict one another.

[0079] In the embodiment shown in FIG. 2 the construct 1000 is in a hydrated or active profile and comprises a generally oblate spherical shaped structure whose outer "skin" defines a material reservoir or pocket 1010. The reservoir 1010 is bounded by a thin, flexible material surface or skin 1013 that encloses an interior volume 1015 for retaining substances that maintain the construct in the active profile. In one such variation, the reservoir 1010 contains a tiller material 1200, which may be a liquid or a semi-solid or gel-like material. In general, the volume of filler material 1200 is initially low, that is, when construct 1000 is in its initial, pre-deployment condition. The volume of filler material 1200 increases after the construct s deployment. Construct 1000 in FIG. 2 illustrates the fully expanded or active state but for clarity only a representative portion of filler material 1200 is shown.

[0080] The transition from initial, unexpanded state construct 1000 to the active state can be effected by increasing the volume of filler material 1200 enclosed in reservoir 1010. Additionally, the volume can be expanded through expansion and/or swelling of the filler material already inside the reservoir 1010. For example, as was described in commonly assigned U.S. patent application publication number US 201 1/0295299, one exemplary embodiment filler material 1200 in the initial state is a pre-determined volume of dry hydrogel granules. The dry hydrogel granules can swell, for example, between 10 and 400 times their dry volume when exposed to an appropriate liquid, generally an aqueous solution.

[0081] In the variation shown in FIG. 2, once a medical practitioner or user deploys of the construct 1000 into the stomach, the aqueous liquid in the stomach migrates into the reservoir 1010 and creates a slurry of liquid and substantially fully hydrated hydrogel. As is well known, hydrogeis absorb water from their surroundings causing swelling of the hydrogel. In the embodiment of FIG. 2, the volume of dry hydrogel is pre-selected to have a fully swollen, unconstrained volume that slightly exceeds the volume of the reservoir 1010. Under constraint, hydrogeis cannot swell to a greater volume than the limits of the constraining volume; however, constrained hydrogeis can and do exert pressure against the constraint. Thus, reservoir 1010 becomes a structurally self-supporting structure, when filled with an excess of swollen hydrogel (that is, when the unconstrained volume of the swollen hydrogel is greater than enclosed interior volume 1015). In other embodiments, reservoir 1010 is filled and pressurized with other filler. In its expanded state, reservoir 1010 can be sufficiently elastic to deform under external pressure and returns to its pre-deformation shape when the pressure is removed. In yet additional variations, the filler material can be selected such that it hardens after a period of time to become its own skeletal structure or to support the skin. Such a filler can be selected to eventually degrade based on the environment in the stomach or digestive tract.

[0082] Assemblies 1000 under the present disclosure can comprise a material surface or skin 1013 that is substantially impermeable to liquids and or gases. In these embodiments, filler material 1200 can be. respectively, a liquid or a gas. Additionally, filler material 1200 can be a lliiid- swellable material such as hydrogel, which, when hydrated, becomes a solid, semisolid or fluidlike gel or slurry. As illustrated in FIG. 2, embodiments comprising a substantially impermeable skin 1010 further comprise a fluid transport member 1100 that allows for the migration of fluid through the skin. In some examples, as noted above, the fluid transport member includes a sealable fluid path that may or may not be coupled to an additional fluid conduit. In additional variations, the fluid transport member can in lude a localized liquid transfer member 1100 that is disposed in an orifice 1020 through the skin 1013 and facilitates the migration of fluid between the interior and exterior of reservoir 1010. One such example can be found in U.S. Provisional application entitled "Resorbable Degradation System" serial no. 61/723,794 filed on 11/08/2012, the entirety of which is incorporated by reference herein [0083] As noted above, in certain variations, where the device assembly 1000 comprises a substantially liquid impermeable material surface, a construct 1000 in the expanded active profile can remain in stomach or other portion of the body indefinitely until released. Therefore, as noted above, devices of the present disclosure can include a release material 1400, which allow the construct 1000 to reduce in size irom the active profile and ultimately pass through the body. Such an active release material 1400 configuration allows for on-demand release of the construct. As noted above, once activated, degraded, or otherwise made unstable, the release material allows migration of filler material from the reservoir and device assembly. In some variations, activation of the release material opens a passage in the skin 1013 of the device 1000. Alternatively, or in combination, activation of the release material can result in reduction of the integrity of the skin forming the barrier about the reservoir. Once the barrier is compromised, the filler material can safely pass into the body. Regardless of the means, the activation of the release material and release of the filler material collapses the device 1000 leading to egress or removal of the device 1000 through the body (in this variation through the lower gastro-intestinal track). As noted above, variations of the devices described herein include a release material that is activated by exposure to an exogenous substance.

[0084] In certain variations, the device assembly 1000, in the active profile, comprises a highly oblate spheroid wherein the skin 1013 can be a thin, film-like material that is soft, tear-resistant, flexible, substantially inelastic, and non-self adhesive. Such features can be beneficial for a device that is to be compressed into a small oral dosage form for administration. In certain examples, the skin 1013 comprised a 0.0015 inch thick polyether polyurethane film. In a simple variation, an oblate spheroid can be created from skins forming an upper material surface and a lower material surface, wherein upper material surface and lower material surface are sealed to each other as shown by seam 1004 in FIG. 2. One such means for sealing the device 1000 comprises an ultrasonic or radio-frequency (RF) weld around the periphery of the surface materials. As will be described in more detail below, in a possible assembly method, the upper and lower material surfaces are formed as nominally identical, substantial!}' disk-like shapes of material, welded in a band around most of their circumferences, the assembly is then inverted (turned inside out) through an unwelded section. Once the assembly is inverted, the welded material forms the seam 1004 that projects inwardly.

[0085] In some variations, as illustrated in FIG. 1C, the release material can comprise a filament, clip, band, cap, or other structure that mechanically closes the edges of the skin. Further, as described below, a source of stored energy, such as a loaded spring or compressed sponge or other material, may be included in the release assembly, where such kinetic energy is also released upon activation of the release material and which may improve the performance of such assembly.

[0086] FIG. 3 illustrates a variation of a fluid transfer member 1100 also having a scalable fluid path 1 1 10 for use with the device assemblies described herein. In this example the fluid transfer member 1100 also includes an elongate fluid conduit, or tube, that passes through a tunnel valve that functions as a scalable fluid path 1 1 1 . The tunnel valve 1 1 10 can be positioned in an orifice in the upper 101.4 or lower 1.01.6 material surfaces or, as illustrated in FIG 4, in an opening in a seam 1004 of the device assembly. This variation of the tunnel valve 1 1 10 comprises an elongate portion 1022 that extends within the reservoir of the device assembly. In some variations, the tunnel valve can extend beyond the seam 1004 or beyond the exterior surface of the device assembly as discussed above.

[0087] As il lustrated in FIG. 3 , a portion of the fluid transport member includes a tunnel valve 1 1 10 that can comprise two layers sealed along their edges, forming an extended orifice 1020 or lumen. In additional variations, the tunnel valve 1 1 10 can comprise a tube structure having a single continuous wall that defines a passage therethrough. In yet additional variations, a tunnel valve can include more than two walls. Regardless of the configuration, the wall or walls of the tunnel valve are predisposed to occluding or blocking flow through the tunnel valve by obstructing the orifice or passage 1020.

[0088] The orifice or lumen 1020 forms a fluid path that allows a remainder of the fluid transport member 1100 to deliver fluids into the reservoir. In this variation the fluid transport member 1100 further comprises a conduit. However, as noted herein, the fluid transport member can comprise a wick type device or any fluid source that allows delivery of fluids into the reservoir of the device. As also noted herein, a variation of the device comprises an attachment of conduit 1100 to a portion of tunnel valve 1 1 10. wherein the attachment may be direct or indirect and wherein, in some variations the attachment is releasable to permit conduit 1 1 00 to be detached, withdrawn, or removed from the tunnel valve 1 1 10. Withdrawal or removal of conduit 1 1 10 from orifice 1020 permits the tunnel valve 1110 to prevent egress of fluids or other substances from within the reservoir. Sealing of the tunnel val ve 1 1 10 can occur via a rise in pressure within the reservoir. Alternatively, or in combination, a number of other mechanisms can result in sealing or closure of the orifice 1020 in the tunnel valve 1110. For example, in additional variations the surfaces forming the lumen 1020 can seal upon contact or the length of the tunnel valve 1110 combined with its flexible nature can simply make it difficult for substances, such as an expanded hydrogel, to travel through the elongated portion 1022 of the tunnel valve.

[0089] FIG. 3 also shows the conduit 1100 extending through the tunnel valve 1 1 10 such that it extends into the reservoir. However, in alternate variations, the device end of conduit 1100 can remain within an interior of the orifice 1020 of the tunnel valve 1110. In such a variation a distal end of the distal portion of the fluid conduit remains within the elongated passage of the fl id tunnel and can rely on flow pressure to propel the liquid through a portion of the tunnel valve such 1 ha I the fluid ultimately ends up in the reservoir.

[0090] In one variation of the tunnel valve 1 1 10, as illustrated in FIG. 4 , the tunnel valve 1 1 10 shaped roughly as the capital letter T, wherein the vertical stem of the T comprises the elongate passage 1022 and wherein the crossbar of the T, in part, forms an increased at tachment surface that can be attached to the skin as noted above. As may be seen in FIG. 4 , tunnel valve 1110 can be disposed through an opening in the seam 1004. In other variations tunnel valve 1 1 10 can be formed as part of the upper 1014 or lower 1016 material surfaces. That is, the templates that are used to cut the upper and lower material surface layers can include elongated tabs that correspond to the upper and lower layers of elongate passage 1022. The seams of said tabs may be sealed during the process of sealing the upper and lower material surface layers, leaving an unsealed, axially extended orifice in the center of the elongate tabs.

[0091] Some examples of materials used to form a tunnel valve include thin, film-like materials. For example, variations include tunnel valve materials that have properties similar to the material used in material surface or skin of the device. Additional materials include but are not limited to polyurethane, nylon- 12, and polyethylene. In certain variations. Suitable materials typically have a durometer hardness of 80 Shore A or softer and are extruded with a glossy finish to enhance cohesion and tackiness. Layers of material in exemplary tunnel valves can typically be between .001 inch or less and 0.1 inch thick. In one example a tunnel valve includes a single layer thickness of 001 inch. One suitable layer material is a 0.001 " thick, high tack polyurethane film.

[0092] The length of the elongate portion 1022 that extends within the reservoir of the device assembly may be short, for example, 0.1 inch or as long as the diametric width of the device assembly. In one exemplary valve the length within the reservoir is approximately 1.25 inches and the width of that portion is approximately 0.75 inches wide. [0093] As discussed above, variations of a device assembly include a release material that is coupled to a portion of the skin to form a barrier to retain substances within a reservoir of the device. FIG. 5 illustrates a partial view of a variation of an invaginated section 126 of a skin 102 of a device assembly 100. As discussed herein, the skin 102 can include a first surface 122 and second surface 124 joined at a seam 118. The seam 118 can include any number of unjoined sections that are intended to function as release areas 128. In the illustrated example, the release area 128 is bounded by an inwardly directed, or inverted section 126, of the skin 102. The particular illustrated embodiment of inverted section 126 is also known as the invaginated section 126, so named as it ma}' comprise a tuck, fold, pucker, bulge, extension, etc. in the skin 102.

Alternatively or in addition, the inverted section 126 can be formed within a first 122 or second 124 surface of the skin 102 rather than within a seam 118

[0094] The release area 128 of the invaginated section 126 ordinarily forms a passage that is flu idly sealed by a release material 106. The release material can comprise a mechanical closure (such as a staple-type structure or a filament that ties together the invaginated structure).

Alternatively, or in combination, the release material 106 can comprise a temporary seal or other joining of the edges of the invaginated section 126. In additional variations, the release material can extend outwardly from an exterior surface of the skin. In some variations, the release material 106 is disposed on the invaginated portion 126 sufficiently close to the skin to be affected by a temperature increase caused by delivery of the exogenous substance.

[0095] In certain variations, the inverted section 126 forms a release area 128 that provides a passage to provide fluid communication between the reservoir and the exterior of the device assembly. This feature allows release of any fluids or material retained within the reservoir to allow the device to reduce in size and pass from the body. The opening can be located at the end of the passage, i.e., at the open edge of the material that is closed together. Alternatively, the wall forming the passage can be porous in an area beyond the point at which the inverted section 126 is bound (e.g., the area disposed inwardly relative to release material 106).

[0096] In additional variations, the inverted section 126 includes an energy storage element that encourages a rapid and more complete opening of the release area 128. Variations of the internal energy storage element can include a solid structure, or a structure that allows passage of fluids. The energy storage element can include a compressible elastic material, for example, a latex foam. In some variations internal energy storage element is generally cylindrical with a diameter at least fractionally smaller than the diameter of the passage in the inverted section 126. When device 100 is deployed in the body, release material 106 is tied firmly around the inverted section 126 at the position of the internal energy storage element, thereby simultaneously sealing the invagination and compressing the internal energy storage element. The resilience of the elastic material in the internal energy storage element creates a tensile force in release material 106 that is greater than the tension in the release material tie used to seal an invagination alone.

[0097] FIG. 6 illustrates an example of an inverted section 126 that is pleated or folded and restrained by a release material 106. The optional energy storage element, if used, is not shown in FIG. 6 for sake of clarity. However, variations of the devices can include energy storage elements that are located between folds or folded into the inverted section 126.

[0098] In another variation, not illustrated, the energy storage element is disposed outside of inverted section 126. An external energy storage element, for example a retaining ring, is used to increase the tension in the cinched and tied filamentary release material 106. The increased tension encourages the release material to break apart sooner, more rapidly, and more completely than it otherwise would. A suitable external energy storage element may be made using, for example, a special order, 5 millimeter diameter, Hoopster© retaining ring, available from Smalley Steel Ring Company, 555 Oakwood Road, Lake Zurich, IL 60047.

[0099] The release area 128 in each of the variations of the inverted section 126 is initially sealed or closed off by a release material that is coupled, directly or indirectly, to a portion of the skin to form a barrier to retain substances within a reservoir of the device. In many variations the release material is filamentary. Examples of release materials that are available in filamentary form can include Polyglycolide (PGA), Polydioxanone (PDS), Po I y{ I act ic-co-g I yco I ic acid) (PLGA), Poly lac tide (PLA), Poly (4-hydroxybutyric acid) (P4HB), Polyglactin 910, and Polycaprolactone (PCL).

[0100] In such variations, the release material in the expanded device assembly degrades over time by hydrolysis where the rate of hydrolysis varies with material selection and liquid filler pH. In variations wherein the release material is PCL the release material can also degrade by elevating the temperat ure of the release material since PCL softens, melts, and weakens above a predetermined temperature. In some cases the pre-determined temperature is greater than normal body temperature. Accordingly, in such variations, the exogenous substance can comprise a heated fluid that can raise the temperature of the PCL without causing injury to the adjacent areas of the body. As the PCL release material degrades, the .structural integrity of the joined region of the release section (such as the" inverted section 126) decreases. In one example, the release material is a modified PCL, wherein the modification comprises lowering the melting point of unmodified PCL from its normal melting temperature to a human-tolerable temperature.

[0101] Examples of the release material can include poly(caprolactone) or PCL. In such variations, PCL softens, melts, and weakens above a pre-determined temperature. In some cases the pre-determined temperature is greater than normal body temperature . Accordingly, in such variations, the exogenous substance can comprise a heated fluid that can raise the temperature of the PCL without causing injury to the adjacent areas of the body. As the PCL release material degrades, the structural integrity of the joined region of the release section (such as the invaginated sect ion 126 ) decreases. In one example, the release material is a modified PCL, wherein the modification comprises lowering the melting point of unmodified PCL from its normal melting temperature to a human-tolerable temperature.

[0102] For example, an on-demand degrading construct composed of nylon- 12 can be constructed by first fabricating a 1 " circular annulus of l.Smil polyether polyurethane. A circular degradable patch of poly(caprolactone) (PCL) (with a modified melting point, T_rrii equal to ~47°C; available from Zeus Industrial Products of Charleston, SC. USA) can be RF- w lded to the polyether polyurethane annulus, covering the hole, creating a T^-modified PCL patch surrounded by a rim of polyether polyurethane. The polyether polyurethane rim can then be RF-welded to a sheet of nylon- 12, which can then be used for further construction.

[0103] Examples of release materials can include biocompatible manufactured polymers. Table 1 is a compilation of the degradation properties of several biocompatible materials that can be extruded or otherwise manufactured in filamentary form and which also can be predictably degraded. Some o these materials, poly(vinyl alcohol ) are stable in dry environments but dissolve very quickly in moist environments. Some biocompatible polymers, for example co-polymers of methacrylic acid and methyl-methacrylate, dissolve in liquids having physiologically relevant pHs. For example, they remain stable at pH < 7.0 but dissolve at pH > 7.0. Other polymers, for example Poly(caprolactone), remain stable at typical gastric temperatures but melt in seconds at temperatures above a pre-determined melting point.

[0104] In some variations, polymers that degrade by gradual hydrolysis may be used for the release material. The degradation times of various polymers, under various degradation conditions, can range from about 2 weeks to about 6 months, where the degradation time depends on parameters such as degradation liquid pH, suture construction (e.g., stranded or monofilament), and filament diameter. In general, polymers last longest when exposed to distilled, neutral pH water and degrade more quickly when immersed in acidic or basic pH liquid.

[0105] The degradation times for several exemplary materials are tabulated in Table 1. The experimentally determined degradation times in the table were determined in simulated use conditions; that is, as illustrated in FIG. 6 , the release material 106 was coupled to an example or simulation of an inverted section 126 that is pleated or folded.

Ta !e 1: Exemplary Relei ise Material Prope rties

Polymer Degradation Degradation Degradation Time

Mode Condition

Poly(glycolic acid) Gradual Exposure to ~ 2 weeks

hydrolysis water or acid

Poly(dioxanone) Gradual Exposure to ~ 1 to 2 months

hydrolysis water or acid

1 PDO 0.9% benzyl 54 days

alcohol

3-0 PDO distilled water 56 days

4-0 PDO distilled water 60 days

4-0 PDO 0.9% benzyl 62 days

alcohol

3-0 PDO 0.9% benzyl 65 days

alcohol

Poly(lactic-co-glycolic Gradual Exposure to - 1 month

acid) hydrolysis water or acid

3-0 PLGA distilled water 25 davs

Polyvinyl alcohol) Rapid dissolution Exposure to any Seconds

aqueous solution

4-0 Monocryl distilled water 27 days

2-0 Vicryl 0.9% benzyl 43 days

alcohol

2-0 Vicryl distilled water 43 days

0 Vicryl distilled water 46 days

0 Vicryl 0.9% benzyl 48 days

alcohol

1 Vicryl 0.9% benzyl 53 days

alcohol

1 Vicryl distilled water 53 days

Methyacrylic acid Hydrolysis: on- Exposure to Days at near neutral pH methyl-methacrylate codemand pH- alkaline pH and minutes to hours at polymers dependent alkaline pH

dissolution

Poly(caprolactone) Hydrolysis: on- Exposure to heat 6 months at

demand at temperatures less than temperatures melting point, seconds greater than 60°C at or above melting

point

[0106] As the release section opens the reservoir to the surrounding environment the opening provides an open path out of the device assembly. The open path allows the contents of the device assembly, such as the filler material, to become exposed to the gastric contents and freely to exit reservoir. When positioned within the stomach, normal gastric churning assists in emptying the contents of the device assembly allowing for the entire device along with its contents to pass from the body. In some variations, the membrane that forms the skin will provide little or no structural support. This configuration allows the body^' s natural squeezing strength to be sufficient to extrude any reasonably viscous substance out of the device assembly.

[0107] FIG.7 provides a schematic illustration of another example of a device assembly 100 having a release material 106 located on a surface of the skin 102. One example of such a release material comprises a degradable patch 106 that, when degraded, opens the physical barrier surrounding the reservoir 104 to allow filler material 108 (swollen or unswollen) to exit the device assembly 100. The device assembly 100 comprises a skin material to which release material 106 can be joined (e.g. by heat sealing, RF-welding, impulse heating, or any other means). In certain variations, the release material/degradable patch 106 comprises a material or combination of materials that remains impermeable to water and hydrogel after deployment and can be degraded "on-demand" in response to an exogenous substance or in response to a condition created within the body being the result of the administration of the exogenous substance.

[0108] In one example, the release material can range from 25 microns thick; up to 2.5 millimeters thick. In another example, release material is a modified poly(caprolactone) with melting point TM - 47°c (available from Zeus Industrial Products of Orangeburg, SC USA ). In additional embodiments, degradable patch 106 may be poly(glycolic acid) or poly(L-lactide acid) (available from Poly-Med, Inc of Anderson, South Carolina).

[0109] Material Surface or Skin

[0110] The type of material or skin will depend upon the intended application. In some variations, a skin will be chosen as a balance of selecting a sufficiently thick film-like material that has adequate strength. For example in some variations, tear resistance can be preferred to enable the finished construct to be compression into as low a volume capsule as possible. The inventors have determined that thin films with a thickness ranging from 0.5 mils to 4 mils are generally suitable. However, the devices described herein can comprise a greater range of thicknesses depending upon the particular application, including a range of thicknesses in different parts of the same construct. In some embodiments, the film-l ik material must be weldable or adherable to other materials such as might be used in valves 1110, filler material release mechanisms 1400, and/or attachment interfaces as described herein.

[0111] In additional embodiments, the film-like material exhibits low transmission rate of filler material, both before and after device expansion. In some embodiment the film-like material exhibits a low moisture vapor transmission rate. Additionally, some film-like material also exhibits high chemical resistance to the variable conditions encountered in the stomach. These conditions include low pH, high salt, high detergent concentrations (often in the form of bile salt reflux ), enzymatic activities (such as pepsin), and the variable chemistries of chyme that depend upon the nature and content of consumed food. For those devices used in the gastric space, the material must also be comprised of biocompatible materials that can safely be in contact with the gastric mucosa for the duration of the treatment course.

[0112] The devices described herein can use numerous thermoplastic elastomers, thermoplastic olefins and thermoplastic urethanes that can be extruded or cast into single-layer or multi-layer films which are suitable for embodiments of the gastric device. Example base resins that may be employed include polypropylene, high-density polyethylene, low density polyethylene, linear low density polyethylene, polyester, polyamide, polyether polyurethane, polyester polyurethane, polycarbonate polyurethane, bi-axially oriented polypropylene, Polyvinylidene chloride, ethylene vinyl alcohol copolymer, and Ethyl Vinyl acetate. Some embodiments comprise single layer films whilst other embodiments comprise multiple layer films. Other embodiments consist of multilayer films including one or more tie layers to prevent layer separation.

[0113] In some embodiments, the film-like material may be coated with other materials. For example, in some embodiments hyaluronic acid coatings can be employed to improve softness and lubriciousness. In other embodiments, coatings such as Parylene ® can be applied to improve the chemical resistance of the gastric mucosa-exposed film surface. In some embodiments, wax coatings, PVDC coatings, vacuum-metallization, or Parylene ® coatings may be applied to the surface of the film to reduce its moisture vapor transmission rate.

[0114] In one example, the film-like material used comprised a 1.5 mil polyether polyurethane film. In other embodiments the film-like material is a 1 mil nylon 12 film or a 1.5 mil LLDPE film. In another example, the film-like material consisted of a multi-layered structure comprising an outer layer of polyurethane, a middle layer of PVDC or EVOH, and an inner layer of polyurethane.

[0115] Filler material

[01 16] The devices described herein comprise two general types; those that are filled with a fluid filler material and those that are filled with a swellable material that is in an unswollen state during ingestion and swells when hydrated by gastric liquids or an exogenous liquid. Generally, a swellable filler material that has a high swelling capacity and achieves a semi-solid consistency is useful to enable the finished construct to be compressed into as low a volume initial state as possible but still maintain rigidity once expanded. However, unless specifically noted, variations of the device can employ a number of different types or combinations of filler materials. During various experiments, it was determined that superabsorbent hydrogel polymers with a mass:mass swelling capacity of between 100 and 1000 are generally suitable, where a mass:mass swelling capacity of 100 is defined herein to mean that l.Og of dry hydrogel will absorb water and swell to become a semi-solid mass of lOO.Og.

[0117] Typically, suitable hydrogels swell maximally in the presence of distilled water and a number of these hydrogels also de-swell (releases bound water) in the presence of the variable environmental parameters encountered in the stomach. For instance, parameters such as pH, salt concentration, concentrations of emulsifying agents (often in the form of bile salt reflux), enzymatic activities (such as pepsin), and the variable chime chemistries, which depend upon the nature and content of consumed food can affect the swelling/deswelling behavior of certain hydrogels. Typical hydrogel swelling times range from between 5 minutes and 1 hour. In one variation, the hydrogel fully swells in under 15 minutes and fully de-swells in less than 10 minutes after exposure in certain environments. Many hydrogels are supplied with particle sizes distributed between 1 and 850 microns, in certain variations, gastric applications benefit from the use of hydrogel particle sizes distributed between 1 and 100 microns. In addition, the hydrogel must also be comprised of biocompatible materials that can be safely in contact with and excreted by the gastrointestinal tract. Examples of such biocompatible superabsorbent hydrogel polymers that possess swelling capacities, swelling times, and de-swelling times suitable for embodiments of gastric construct include poly(acrylic acid), poly(acrylamide), or co-polymers of poly(acrylic acid) and poly(acryl amide). Another such material that can be used as a filler material is a crosslinked poly( acrylic acid) with particle size distribution ranging from 1-850 microns and swelling capacity of 400.

[0118] Shapes

[0119] As discussed above, certain variations of the device approximate a highly-oblate spheroid comprising a diameter in the X-Y plane and a thickness along the Z-axis as illustrated in FIG. 2. in certain variations, the expanded dimensions of the device assembly can range from having a diameter between 2 inches and 10 inches. In another embodiment, the diameter of the construct is approximately 4.6 inches. The Z-axis thickness can range between 2 inches and 5 inches.

However, the device assembly, unless otherwise claimed, is not limited to any particular dimension. The data below of construct parameters provides the experimentally determined dimensions of two constructs having the oblate spheroidal shape.

[0120] Liquid Transfer Valves

[0121] FIG. 8 shows an additional variation of a portion of a device assembly, in other embodiments liquid transfer member comprises a valve 150, wherein valve 150 is disposed in orifice 148 and provides a control over the fluid permeable path through otherwise impermeable material surface 102. In some embodiments valve 150 comprises a multilayer material structure composed of regions of permeability 152 juxtaposed against regions of impermeability 1 4, whereby fluid may transmigrate between the exterior and the interior of reservoir when the regions of permeability 152 and impermeability 154 are not pressed together in tight juxtaposition and whereby fluid is inhibited from transmigrating when the regions 152, 154 are pressed together tightly. In some embodiments valve 150 is self-closing. That is, valve 150 changes from allowing fluid transmigration to inhibiting fluid transmigration without external activation. In one embodiment valve 1 50 self-closes in response to the increasing pressure of the expanding filler material or increasing pressure within the reservoir, for example, swelling hydrogel pressing the regions 152, 154 sufficiently close together to form a barrier.

[0122] As noted above, the device assemblies described herein can include a fluid transport member 1 10 that serves to deliver fluids into the reservoir. One example of such a fluid transport member is a wick that includes a filamentary material capable of conducting a liquid from one end to the other by capillary action. The wick can extend from the interior of the device reservoir to outside the device skin, typically just several millimeters beyond the skin although longer wicks may be used. In another example, the liquid transfer mechanism 1100 comprises a fluid conduit 114, tube, or catheter that, after the device is extends from the deployed device in the patient's stomach to outside of the patient where it is connected to a source of filling fluid. In many embodiments the fluid flow through the fluid transport member is preferably shut off once the device has reached its desired deployment profile. In embodiments comprising a wick-like fluid transport mechanism the fluid flow may be shut off by pinching down on the wick while in embodiments comprising a catheter-like fluid transport mechanism the fluid flow is halted externally and the catheter- like mechanism is withdrawn from the device first and from the patient second. When the catheter-like mechanism is withdrawn from the device it is necessary to seal the orifice through which the catheter passed through the skin of the device. In many of the assembl ies described herein fluid flow is inhibited by a self-sealing, two-layer valve. In other embodiments the self-sealing valve has more than two layers.

[0123] In yet other embodiments liquid transfer mechanism 1100 comprises a mechanical valve. Mechanical valves of suitably small dimensions, comprising biocompatible materials, are well known in the art and are commercially available. A mechanical valve that serves as liquid transfer mechanism 1 100 comprises a one-way or "check" valve design which allows fluid to enter reservoir 1010 but prevents fluid from exiting the reservoir. Alternatively, a mechanical valve that serves as liquid transfer mechanism 1100 may have a normally open state but which self-closes when internal fluid pressure is greater than external fluid pressure.

[0124] FIGS. 9A and 9B schematically illustrate one example of a valve that self-seals by the expansion of filler material 234 within a reservoir 236 of the device assembly 230. The valve 232 is positioned or otherwise disposed in an orifice 238 in the material surface or skin 228. In other embodiments orifice 238 may be an unsealed section of seam 1004, as illustrated in FIGS. 3 and 4. In the illustrated variation valve 232 comprises two material containment layers 242. Containment layers 242 are at least partially permeable to fluids but may be impermeable to non -fluid filler materials. This permeability may be achieved by a sieve- like structure or, as illustrated in FIG. A, permeability may be achieved by puncturing an impermeable layer with at least one hole 242. Valve 232 further comprises regions of flow control material 240. Flow control material 240 is substantially impervious to fluids, specifically to the fluid used as filler material 234 or to hydrate a dry mass of fi ller material. As illustrated, the regions of flow control material are disposed directly juxtaposed to the permeable regions of containment layers 242. During deployment there is initially no pressure within the device assembly. With no pressure the juxtaposed flow control material and fluid permeable regions of the containment layer are able to separate, creating a fluid flow path. [0125] This flow path is indicated by the dashed arrow in FIG. 9A. In some variations a fluid transfer member, not illustrated, is used to transfer fluid from outside the device assembly to the internal reservoir. In these variations the containment layers may be made from fluid impermeable material with a hole in each containment layer to allow the selected fluid transfer member to pass into the reservoir. The transfer member is inserted through the valve prior to deployment. In some variations the transfer member is a wick while in other variations the transfer member is a fluid conduit or catheter.

[0126] FIG. 9A also illustrates a pre-determined amount of filler material 234 within the reservoir 236. In some variations, the pre-determined amount is generally measured by dry mass. The dry mass of filler material 234 is determined by the amount of filler material 234 needed to fill the known volume of the expanded device 230 when the filler material is folly hydrated. When expanded, the filler material applies a pressure within the reservoir 236, which provides a shape- restoring force that resists externally applied deforming forces. In other variations filler material 234 is not pre-loaded within reservoir 236. In these variations the filler material is a fluid or slurry material delivered through a fluid transfer member, generally embodied as conduit 114, as shown, for example, in FIG. 1 D.

[0127] FIG. 9 A also shows valve 232 filling orifice 238.This variation of the valve 232 includes one or more flow control layers 240 that aid in closing of the valve upon action by the filler material 234. FIG. 9B illustrates expansion of the filler material 234, which increases pressure against the valve 232 and closes the fluid path by pressing the flow control layers 240 toward their respective material containment layers such that the fluid path is closed.

[0128] In some variations the design may be simplified to comprise just two layers of fluid impermeable material through which passage holes have been created to allow the fluid transport member to pass. This variation is discussed further below in conjunction with FIGS. 9C and 9D.

[0129] Turning back to FIG. FIG. 9A, before filler material 234 expands, valve 232 is folly open; that is, it allows fluid to pass through the valve in either an inward or outward direction. On the other hand, after filler material 234 expands, typically via hydration, the valve 232 fully closes, as shown in FIG. 9B.

[0130] In some embodiments valve 232 comprises a filler material containment layer 242.

Generally, containment layer 242 is at least partly fluid permeable and simultaneously able to contain filler material 234, in its dry or its hydrated state, within device 230. In some embodiments filler material containment layer 242 is also a flow control layer; that is, a single layer in valve 232 can simultaneously be a part of the flow control function of valve 232 and perform the filler containment function of containment layer 240. For example, laser micromachining may be used to create microperforations in one region of an otherwise fluid impermeable membrane. The microperforated region functions as the containment layer while the imperforated region can function as the flow control layer.

[0131] Similarly, in variations in which the filler material is a fluid or slurry material that is delivered to the reservoir by a conduit or catheter, each of two fluid impermeable may be punctured by catheter passage holes 242 A, as illustrated in FIG. 9C, to create permeable regions to al low the catheter, not illustrated, to be threaded from the exterior of the device to the interior of the device when the device has no filler material in the reservoir. The path of the catheter is illustrated in FIG. 9C by the dashed arrow. FIG. 9C illustrates this variation of the valve schematically in the "open" configuration that would obtain immediately after deployment but before the filler material was hydrated and FIG. 9D shows the same valve after the filler material is fully hydrated and the conduit has been extracted. As shown in the figures the gap between the two layers in FIG. 9C is pushed closed in FIG. 9D by the pressure of the filler material in the reservoir. This closing pressure occurs with both hydrated swellable filler material, as illustrated, and when the filler material is just a fluid pumped into the reservoir under pressure.

[0132] FIG. 9E show another variation of a valve 232. In this example the valve 232 comprises more than one layer. As shown, this hybrid valve 232 comprises two demilunar hybrid flow control layers 240, each of the layers having a hybrid construction being permeable in some generally semi-circular (viz., demilunar) regions 250 and impermeable in other regions 252. The impermeable regions 252 of one layer are at least complementary to the permeable regions of the second layer; that is, where one layer has a permeable region the other layer has an impermeable region; generally there will be regions in which both layers are impermeable. Examples of the materials include a permeable patch comprising a polyester mesh and an impermeable semicircular patch comprising latex.

[0133] As illustrated in FIG. 9E, hybrid valve 232 comprises two substantially identical demilunar hybrid flow control layers, one on top of the other, wherein the two layers are oriented so that impermeable region 252 of a first hybrid control layer is aligned with the fluid permeable region 250 of a second hybrid flow control layer. By symmetry, impermeable region 252 of second hybrid flow control layer is aligned with the fluid permeable region 250 of first hybrid flow control layer. The two layers are affixed, typically with glue, around their periphery only, thereby allowing the central areas of the two layers to move apart freely.

[0134] In these exemplary embodiments of a hybrid valve, the flow control layer disposed on the internal side of the valve preferably can also function as filler material containment layer, with containment being achieved by the mesh comprising permeable patch. Alternatively, a separate innermost filler material containment layer must be added to the assembly.

[0135] In other embodiments, hybrid flow control layer is fabricated by joining a patch of permeable material and a patch of impermeable edge-to-edge, wherein the joint may be a butt joint, for example, or a lap joint, for a second example, wherein further the outer periphery of the edge-joined materials is designed to fill or cover orifice. In another exemplary embodiment of a hybrid valve the skin itself can serve as one of the flow control layers.

[ 136] Another variation of a multi-layer, self-closing valve is a tunnel valve. FIG. 10A is a schematic illustration of a variation of a tunnel valve as discussed above. As shown, the tunnel valve forms a scalable fluid path that prevents material from escaping from the interior of the device. FIG. 10A illustrates an example of a device with a tunnel valve forming the scalable fluid path. As shown, the device assembly contains a valve member 330 comprising a liquid

impermeable material that can be securely joined to the skin 328 in any manner conventionally known or by those discussed herein (including, but not limited to gluing, welding, heat sealing, or other means). Examples of materials useful for the tunnel valve include polyurethane, nylon- 12, and polyethylene. The tunnel valve 330 can include any number of fluid transport members 332. In the illustrated vaiiation, the valve is coupled to a conduit. However, variations include a wick type device located within the tunnel valve.

[0137] FIGS. 10B 1 - 10B3 show a cross sectional view of tunnel 330 taken along line 10B- 10B of FIG. 10A. As shown in FIG. I OA, the tunnel valve 330 forms part of the fluid transport member 332 allowing transport of fluids between the interior/reservoir and interior of the device assembly. In general terms tunnel valve 330 comprises, for example, a rectangular upper layer 340 and a matching rectangular lower layer 341 that are sealed together along their longer edges but are left unsealed along an axial central region. The unsealed region forms a lumen 343 that extends from the exterior of the device int the interior reservoir and through which fluid may flow or through which a fluid transport member may pass from the exterior of the device into the interior reservoir. In some variations the fluid transport member may be pushed through the lumen by spreading the layers apart. In certain variations, the fluid transport member 332, can be detachable from the tunnel valve 330 . Upon removal of the fluid transport member 332, as shown in FIG. I OC, the layers of the tunnel valve 330 move toward each other to eliminate the central lumen 343 to an extent that the tunnel valve closes and prevents migration of the filler material from the reservoir. In certain variations, the tunnel valve 330 fully closes, while in other variations, the tunnel 330 can remain slightly open. This self-closing behavior (that is, the closing behavior is initiated and completed without any external force, stimulus, energy, or action beyond the removal of the fluid transport member 332) is effected by one or more physical mechanisms. In some variations the mechanism is the natural elasticity of the layers of the valve working to restore the layers to their initial, flat, in-contact condition. In other variations the pressure of the filler material in the reservoir presses the layers, which were held apart by the fluid transport member, together.

[0138] One variation of the tunnel valve, illustrated in FIG. 10B 1 , includes an assembly formed by two discrete membrane layers, the upper layer 341 and the lower layer 342, that are joined by gluing, welding, heat sealing, or other means along their two edge regions 344 as indicated by bond line 345. In another variation, illustrated schematically in FIG. 10B2 the assembly may be formed by a single membrane that has been folded in half with a fold 346 that is parallel to central lumen 343, wherein again the two regions parallel to and bordering central lumen 343 are joined together by gluing, welding, heat sealing, or other means. In some variations RF welding has been used. After the joining process is complete, the material in fold 346 may be cut away or otherwise removed or it left in place. In a third variation, shown schematically in FIG. 10B the assembly may be formed by a sleeve of membrane material, for example, fabricated by extrusion. Flattening the sleeve creates an assembly with the two desired layers. The central lumen can be formed by again joining together the two regions parallel to the lumen by gluing, welding, heat sealing, or other means and again, after the joining process is completed, the thusly created two folds 346 may be left in place or removed. Functionally these variations of the tunnel valve are equivalent and the choice of fabrication approach will be determined as an engineering decision.

[0139] In exemplary tunnel valves the layers can typically be between .001 inch or less and 0.1 inch thick. In one example a tunnel valve includes a single layer thickness of 001 inch. One suitable layer material is a 0.001 " thick, high tack polyurethane film.

[0140] In some variations the tunnel valve has a length (parallel to the central lumen) of between about 0.5 inches and 2.75 inches and a width of between 0.25 inches and 0.75 inches, although both larger and smaller tunnel valves are possible. The central lumen runs the full length of the tunnel valve and has a width, in one variation, of 0.095 inches, where the width is a design choice determined by the size of the particular fluid transport member 332 selected.

[0141] In additional variations, tunnel valves can be flexible, compressible and/or deformable. In additional variations, the lumen between the layers of the tunnel valve can be reopened after fluid transport member has been removed by the insertion and passage of a structure (e.g., a conduit or other fluid transport structure) through the closed tunnel valve.

[0142] As noted above, the tunnel valve allows for detachment of the remainder of the fluid transport member at any time, but typically once a sufficient amount of fluid is delivered to the device. Removal can occur via applying tension to a portion of the fluid transport member.

Variations of the tunnel valve can employ permeable membranes, filter, or valves placed at the end of the tunnel valve to prevent dry hydrogel or other filler materials from entering the tunnel and affecting the ability of the tunnel valve to seal. In some embodiments, the membrane or filter may comprise a permeable fabric such as polyester, nylon, or cellulose. In other embodiments, a valve is placed at the end of tube comprised of a one-way duckbill or umbrella valve (available from Mini Valve of Oldenzaal, Netherlands). Alternatively, or in addition, filler material 234 can be contained in an inner container which prevents the filler material from entering the tunnel valve and swelling upon infusion of liquid, thereby clogging the valve.

[0143] Referring to FIG. 10D, tunnel valve 1110 comprises an interior section Γ110Α, which section is disposed inside the device assembly, and an exterior section 1 1 10B that extends outwardly from the exterior of the skin. Interior section 1 1 1 OA comprises a distal end 1 1 1 OA 1 , which is fabricated from flexible membrane-like materials. Once the device assembly is fully expanded, conduit 1100 is withdrawn distal ly from lumen 1020. In some circumstances the drag between the conduit and the walls of the lumen as the conduit is withdrawn may result in interior section 1 1 10A "accordioning" or folding itself against the walls of the device. In some variations interior section 1 1 1 OA of the tunnel valve is attached to an interior surface of the device body to prevent such folding. In some variations the attachment is achieved by fastening distal end i i lOAl to either upper material surface 1014 or lower material surface 1016. In one variation a spot of glue is employed. The glue spot is disposed near to distal end 1 1 1 OA 1 but in such a manner to avoid accidentally obstructing orifice 1020; for example, the glue spot may be disposed 2 or 3 millimeters proximal to distal end I I I OA I . Tunnel valve 1110 is rotated about seam 1004 until distal end 1 1 1 OA 1 touches the material surface. Tunnel valve 1110 and the material surface should both be smooth and flat during this gluing operation. [0144] In additional variations, as shown, for example, in FIG. iOD, a portion of the tunnel valve extends outside the device assembly to form an external section 1 1 10B. In some variations, as shown in FIG. 10G, external section 1 1 1 OB terminates with two unjoined flaps, upper flap 1028 and lower flap 1026, which may be extensions of upper layer 341 and lower layer 342

respectively. In other variations external section 1110B may comprise a single flap or layer of material . In some examples, external section 1 1 10B is typically between 0. 1 inch and 0.5 inch long. As will be discussed below with reference to FIG. 14, in some variations the layers of the tunnel valve are fabricated as integral parts of the upper and lower skins of the device. In these variations there is no material available to form the upper and lower flaps as extensions of the upper and lower layers, in which case a free-standing external upper flap 1028 and or lower flap 1026 may be attached to the external surface of the device using any convenient joining method, for example, gluing or they may be attached in the seam. The free-standing flap or flaps are joined to the device in close enough proximity to the tunnel valve to be able to touch a fluid transport member disposed through the central lumen of the tunnel valve.

[0145] In some variations the tunnel valve comprises retaining elements to releasably hold the conduit in place throughout deployment of the device assembly. FIG. 101) illustrates one embodiment for retaining the conduit in a partial cut-away view from the interior of the device assembly. Tunnel valve 1110, as described above, is typically formed by sealing the edges of two layers of membrane material to form sealed seams 1024. In some variations sealed seams 1024 extend all the way to a proximal end 1 1 10B 1 and/or distal end 1 1 1 OA 1 while in other variations the edges of the two layers may be unsealed for some length inward from proximal end 1110B 1 and/or distal end 1 1 10A1. The relative lengths of the interior and exterior sections of tunnel valve 1 1 10 have been distorted in the figure for clarity purposes. Typically exterior section 1 1 10B is just long enough to accept conduit 1 100. As has been discussed, conduit 1 100 is inserted through orifice 1020 prior to deployment of the device assembly and is used to deliver fluid to the reservoir therein to expand device assembly. Conduit 1 100 must remain disposed in tunnel valve 1 1 10 until enough fluid has been delivered to the device assembly to make it too large to inadvertently pass through the pylorus while at the same time conduit 1 100 must be removable from the device assembly once its deployed profile has been achieved. Further, it is desirable that conduit 1100 also be useful for retrieving the device assembly from the stomach or esophagus in the case of an aborted deployment. In such an aborted deployment the conduit must be held in the tunnel valve with enough resistance to withstand the drag on the unexpanded device assembly as it is retrieved upwardly through the esophagus.

[0146] A suture 1032, which may be inserted through either or both of interior section 1 1 1 OA or exterior section 1 1 10B , is designed to hold the conduit in the tunnel valve under a wide range of extractive force. As illustrated in the figure, suture 1032 is stitched through the two layers of the tunnel valve, simultaneously passing through conduit 1 100. The suture is tied to itself on the exterior of tunnel valve 1 1 10. The small punctures in conduit 1 100 and tunnel valve 1 1 10 through which the suture passes are too small to allow any significant loss of liquid filler.

[0147] Once the device assembly has assumed its deployment profile conduit 1100 must be withdrawn from tunnel valve 1 1 10. Conduit 1 100 is released from tunnel valve 1 1 10 by the controlled, on-demand degradation of suture 1032. As is discussed above certain suture materials can be dissolved or structurally weakened by exposure to specific exogenous agents not normally in the gastric environments, or not in the gastric environment in high enough concentrations to degrade the suture during the deployment time period. For example, poly(caprolactone) [PCL] softens, melts, and weakens above a pre-determined temperature, TM- In some cases the predetermined temperature can be designed to be greater than normal body temperature but lower than human' s physiologic pain threshold. In such a case, a PCL suture can be degraded by infusing heated liquid (above TM) through conduit 1100 at the end of the deployment period or by having such l iquid consumed orally.

[0148] In order to avoid over- filling the device assembly when the heated l iquid is infused through the conduit the hot liquid infusion must start at after a pre-determined volume of un-heated liquid filler material has been infused, where the known capacity of the device assembly, the volume of fluid residual in the conduit, and the thermal capacity of the system are all incorporated into the determination. It should be noted that if the initial infusion of hot liquid fails to rel ease the conduit by melting the suture, liquid can be withdrawn up the conduit to slightly reduce the volume of the device assembly and a second charge of hot liquid infused.

[0149] In another variation, as depicted in FIG. 10E and FIG. 10E, conduit 1 100 is detachably joined to one or both double layer sealed seams 1024 of tunnel valve 1 1 10 with a loop of suture material 1032. Suture loop 1032 comprises a single long loop which starts and ends at the proximal (e.g., patient' s mouth) end of conduit 1 100. The loop starts at the proximal end, runs down the interior of conduit 1 100, and exits the conduit at a small orifice 1036 that transverses the wall of conduit 1 100 near the proximal end of exterior section 1110B. After exiting from orifice 1036, the suture passes through one or two eyelet holes 1034 in sealed seams 1024 before returning to orifice 1036. The suture completes its loop by running back up the interior of conduit 1 100. The two ends of suture loop 1032 are retained at the proximal end of conduit 1100.

[0150] .Suture loop 1032 is installed during the manufacture of the device assembly and remains disposed in conduit 1 1 10 during infusion of the liquid filler material. Conduit 1 1 10 cannot easily be pulled out of tunnel valve 1110 while suture loop 1032 is in place. Once the device assembly has assumed its deployment profile, one end of suture loop 1032 may be released while the other end of the loop is pulled outwardly. When at least half the length of suture forming suture loop 1032 has been withdrawn from conduit 1 100, the loop is known to be unthreaded from the eyelet hole(s). Freed from the eyelets, conduit 1 100 can then be withdrawn from tunnel 1 100.

[0151] In some embodiments suture loop 1032 of FIGS. 1 OF and 1 OF may be made from PCL, i which case conduit 1110 may also be released by melting suture loop 1032 through the infusion or ingestion of hot liquid, as described above.

[0152] Another variation of fluid transport member 1100 is illustrated in FIG. lOG. In this variation sealed seams 1024 stop short of proximal end 1110B 1, leaving two flaps of material, upper flap 1028 and lower flap 1026. where upper and lower are arbitrary designat ions relating only to the figure. Upper flap 1028 or lower flap 1026 is prepared with a release region in the form of a rip-off tab 1030 which comprises the most proximal section of upper flap 1028 and which is distinguished as the region sectioned off by a tear line 1038 of diminished tear-strength material. The tear-strength of tear line 1038 may be reduced, for example, by perforations, physical thinning, or chemical application (e.g., partial de-polymerization). In some variations the tear- strength of tear line 1038 is between 1 and 1.5 lbs. while other variations may have tear-strengths between 0.5 lbs and 2.5 lbs.

[0153] In some variations the length of flaps 1028, 1026 is approximately 0.5 inches and tear- line 1038 is disposed approximately 0.3125 inches from the exterior surface of the device.

[0154] As il lustrated in the figure, conduit 1 100 is attached to rip-off tab 1030 at spot location

1040 proximal to tear line 1038, where such attachment may be accomplished, for example, by gluing, melting, or ultrasonic welding. In some variations the attachment point, spot location 1040, is at least 0.0625 inches away from tear line 1038. In this variation conduit 1 100 is detached from tunnel valve 1 1 10 by pulling outwardly on conduit 1 100 with enough force to separate rip-off tab 1030 from upper flap 1028 along tear line 1038. Although depicted examples show only a single rip-off tab 1030, additional variations include two or more rip-off tabs, one such tab on each of the two flaps, wherein conduit 1100 is attached to both tabs.

[0155] In some variations, as depicted in FIGS. 10H1-10H3, which show a cross sectional view of tunnel valve 1 1 10 taken along line 1 OH- 1 OH of FIG. 10B 1 , the deposition of a packing substance 1046 between the layers of the tunnel valve may enhance the sealing effectiveness of tunnel valve 1 1 10. It wi ll be noted that a packing substance, in this context, means a material that surrounds and fills, as in the "packing of a bearing", and is not a substance used in packaging. In some variations packing substance 1046 is a fluid swellable material. In these variations the swellable material generally remains unswollen while the conduit 1 100 is installed in the valve. After conduit 1 100 removal, swellable material intercepts any liquid or semi-liquid filler material from the reservoir that migrates between the two layers of the nominal ly sealed valve. The swel lable material swells in response to any liquid component i n the intercepted fi ller material, thereby blocking further filler material migration through the valve.

[0156] The swellable material 1046 is typically superabsorbent poly(acrylic acid) hydrogel granules or superabsorbent poly( cryl ic acid) hydrogel fibers. The swelling ratio of these substances (the mass of water absorbed for every gram of substance) is typically greater than 10.

[01 7] In other variations the packing substance is a grease or grease-like lubricating material. The lubricating material is bio-compatible, being designed for use in the stomach, and is selected to have a high enough viscosity to remain in the central lum n for the expected duration of deployment. Typically the material is not soluble in water to any significant degree. In some variations the material is a high consistency dimethyl silicone grease.

[0158] In some variations packing material 1046 is inserted into central lumen 1020 prior to the insertion of conduit 1 100 while in other variations the packing material is injected into the lumen and around the conduit after the conduit has been inserted through the lumen.

[0159] As il lustrated schematically in the cross-sectional view in FIG. 10H 1 , central lumen 1020 has a diameter over most of its length that closely matches the diameter of conduit 1100. This snug fit reduces the leakage of filler material during the filling process since filling material in the reservoir can enter the distal end 1 1 10A1 of the lumen in the space around the exterior of the conduit. The dashed line A- A' indicates the skin of the device assembly. Generally packing material 1046 is disposed toward the distal end of valve 1 1 10 although in some variat ions it may be disposed towards the proximal end of the valve in the region approaching but not including the region of the unjoined flaps, as shown in the cross-sectional figure as upper flap 1028.

[0160] As depicted in the cross-sectional view schematical ly in FIG. 1 112, in some variations lumen 1020 is tapered in one or more regions 1042, 1044.The region between the two tapered regions forms a pocket into which the packing material may be disposed. In embodiments with only one tapered region the region will typically be disposed near distal end 1110A1 and the packing material 1046 will be disposed to the proximal side of the tapered region. Tapered regions 1042 and 1044, may have a design diameter so that the conduit 1100 fits snugly through the tapered regions and less snugly in the untapered regions. That is, the diameter of the tapered regions is substantially equal to the diameter of the conduit. The tapered region can then prevent most of the liquid filler from reaching the packing material while conduit 1 100 is in place, inhibiting any swelling of a swellable packing material or any migration of the packing material out of the lumen during storage. This variation is particularly suitable for a swellable packing material, which in many variations comprises dry, flowable granules. Once the conduit is removed any fluid that follows the conduit up the lumen is intercepted by the swellable material which then swells and blocks the flow of additional fluid.

[ 1 1 ] Another variation is illustrated schematically in the cross-sectional view in FIG. 10H3. In this variation lumen 1020 comprises an enlargement region or pocket 1047 into which an extra volume of packing substance 1046 may be inserted. This variation is similar in function to the variation illustrated in FIG. 10H2. It may be advantageous compared to that variation in that the diameter of the lumen may be snugly fit to the catheter over a longer length than is possible in the variation of FIG. 10H2, thus providing better containment of the packing material in the pocket and greater resistance to filling fluid flow out of the reservoir.

[0162] In some embodiments the seal of valve 1 1 10 may be enhanced mechanically, as illustrated in FIG. 101. In this exemplary embodiment a spring-loaded closure device 2000 is disposed on elongate portion 1022 of valve 1 1 10. Closure device 2000 comprises two, U-shaped loops 2 1 OA, 2010B, loops 2010 in this exemplary embodiment being connected at a hinge axle 2015. Each loop 2010 comprises a width comparable to the width of elongate portion 1022 and a length, L, which is the length of each loop 2010 extending from hinge axle 2015. For clarity, the loops are illustrated with exaggerated lengths. [0163] Device 2000 further comprises a spring 2020 or similar energy storage element. Loops 2010, hinge axle 2015 and spring 2020 are configured to allow spring 2020 to drive loops 2010 into generally adjacent alignment by rotating one or both loops around hinge axle 2015, as indicated by arrow A in FIG. 101.

[0164] During deployment, conduit 1 100 is disposed within orifice 1020, typically extending through substantially the entire length of elongate portion 1022. As previously noted, in some embodiments conduit 1100 extends beyond the end of orifice 1020, as illustrated in FIG. 101. Closure device 2000 is disposed in its "open-flat" configuration on or around elongate portion 1022, whereby elongate portion 1022 is threaded through closure device 2000 by passing above loops 2010 and below hinge axle 2015.

[0165] Elongate portion 1022 is, by design, stiff enough to hold closure device 2000 in its open- flat configuration during deployment. It will be noted that elongate portion 1022 is stiffened during deployment by the presence of conduit 1100 since, as described herein, elongate portion 1022 is fabricated with two thin layers of a membrane-like material designed to collapse upon themselves while conduit 1 100 must be rigid enough to provide an open fluid channel from a patient's mouth to his stomach.

[0166] After deployment, conduit 1100 is withdrawn from orifice 1020. Once the end of conduit 1100 passes the crossbar of loop 201 OA, elongate portion 1022 is no longer stiff enough to retain loop 201 OA in its open-flat configuration. Loop 201 OA is rotated by torsion spring 2020 in the direction of arrow A, wrapping the distal end of elongate portion 1022 around hinge axle 2015 in the process. Loop 2010A continues rotating until it rests against loop 2010B, simultaneously pressing and sealing the doubled over elongate portion 1022.

[0167] In an alternative exemplary configuration, illustrated in side-view in FIG. 10J, closure device 2000 may be used as a spring clamp only, without the doubling over functionality discussed above. As shown, during deployment closure device 2000 is disposed in its open-jaw

configuration, with elongate portion 1022 inserted into an open jaw 2012 formed by loops 201 OA and 2010B. During deployment conduit 1100 inside elongate portion 1022 is stiff enough to hold jaw 2012 open; when conduit 1100 is withdrawn, the force of torsion spring 2015 closes jaw 2012, sealing elongate portion 1022.

[0168] In another embodiment, not illustrated, an elastic ring provides the mechanical assistance for enhancing the seal of valve 1110. The ring is disposed around on elongate portion 1022 of valve 1 1 10. The ring's material properties and dimensions are selected to substantially seal the tunnel valve when the valve does not contain conduit 1100. However, when conduit 1100 is positioned within the tunnel valve, the rigidity of the conduit resists the sealing force of the elastic ring. The elastic ring may be composed of any elastomeric material that is known to be

biocompatible. Examples include silicone, polyurethane, and latex.

[0169] As was described above, in some variations of a tunnel valve the two layers of the valve, upper layer 341 and lower layer 342, are fabricated as integral parts of the upper material surface 1014 and lower material surface 1016 of the device. A device having integral tunnel valve layers shown in mid-fabrication in the plan view of FIG. 14 A. As previously described, in a simple variation, an oblate spheroid device can be created from two pre-formed skins formed by upper material surface 1014 and lower material surface 1016, wherein upper material surface and lower material surface are sealed to each other as shown by seam 1004 was shown in FIG. 2. In one exemplary fabrication method each of the two material surfaces are thermoformed into hemi- ellipsoids by heating a sheet of membrane material 1 14 A or 1016A in a frame and forming it over a vacuum mold wherein the mold has the desired hemi-ellipsoidal shape. As illustrated in exploded cross-sectional view FIG. 14B, after cooling and upon removal from the vacuum mold, each sheet of membrane material, membrane materials 1014 A or 1016A, retains the hemi-ellipsoidal shape of upper material surface 1014 or lower material surface 101 , albeit in a collapsed or crumpled form, the membrane material being thin and flexible. It will be noted that each formed sheet has a preferred interior surface 1 141, 101 61 and a preferred exterior surface 1014E, 1016E, where the interior surfaces comprise the concave side of the molded hemi-ellipsoid. As illustrated in FIG. I4B, the two sheets are disposed with their interior surfaces facing each other and in proximal contact with any corresponding features aligned.

[ 170] The two sheets are then joined around the periphery of the hemi-ellipsoids to seal them together along sealed seam 1004. One method for sealing the device 1000 comprises an ultrasonic or radio-frequency (RF) weld. I the example shown i FIG. 14 the device includes a tunnel valve in which the two layers of the valve are integral to the upper and lower material surfaces. As shown in FIG. 14 A and 14B, the integration of the valve upper layer 341 and lower layer 342 into the device surface material can be accomplished by configuring the joining, welding, or gluing fixture to form a pair of seams projecting in an outwardly radial direction relative to the nominally circular seam around the material surfaces. These projecting seams are formed in a flat region of the membrane material and are disposed generally parallel to each other and spaced by a gap substantially equal to the desired diameter of central lumen.

[0171] After joining the device is trimmed to remove the excess material along a trim line 1006. Either before or after joining an access aperture 1410 is opened in one of the material surfaces. Typically this aperture is circular although it appears distorted in FIG. 14A due to the crumpling of upper material surface 1 14. As wil l be understood, when the device is inverted by pulling the lower material surface 1016 through aperture 1410 to put seam 1004 on the interior, the outwardly projecting tunnel valve formed by upper and lower layers 341 and 342 is converted into the desired inwardly directed valve.

FABRICATION METHOD

[0172] As described above, one method for fabricating balloon-type devices from thin film-like polymeric working material comprises the steps of forming two device sections, for example by thermoforming, and subsequently joining the two sections together by a peripheral weld that creates an external seam. In many cases the device is inverted to convert the external seam into an internal seam, as is often done in clothing manufacture. In some variations of the method a backing layer, also a polymeric material, is left attached to the working material until after the joining step. In the following paragraphs a more detailed description of the fabrication method is presented.

[0173] In one variation of the fabrication method each of the two device sections is fabricated from a working layer comprising a thin film of polymeric material such as polyurethane (PU). In some variations the working layer may be provided as a standalone film while in other more typical variations the working layer is adhered to a backing layer. In some cases, the backing layer is another suitably selected polymeric material, for example polyethylene (PE). In yet other variations the working layer is sandwiched between two backing layers. In an exemplary embodiment the working layer is PU and the two backing layers are PE. Other polymeric materials are also available for use in this fabrication method.

[0174] The PU thin film material may be extrusion cast. In a cast film extrusion process molten polymer travels through a flat die system comprising a die and feedblock (if the process requires co-extrusion of, for example, a polymeric backing layer). The thin film is extruded through a slit onto a chilled, highly polished turning roll, where it is quenched from one side. The speed of the roller controls the draw ratio and final film thickness. The film is then sent to a second roller for cooling on the other side. Finally it passes through a system of rollers and is wound onto a roll. [0175] Alternatively, the PU thin film material may be blow extruded. Blown film extrusion is a technology that is the most common method to make plastic films. The process involves extruding a tube of molten polymer through a circular die and inflating to several times its initial diameter to form a thin film bubble. After cooling, this bubble is then collapsed and can be slit to be used as a lay- flat film. As with cast film extrusion, co-extrusion is possible. In particular, a three layer sandwich o PU with two PE backing layers can be co-extruded with this process.

[0176] In one exemplary embodiment, shown in FIG. 15, the material is a three layer co-extrusion comprising a 0.0025 inch thick working layer of polyurethane layer sandwiched between two polyethelene backing layers 5020, each 0.0025 inch thick. In some variations the selection of backing layer material is best left to the extruder of the thin film, based on the engineering requirements for forming and joining by this device fabrication method, in one variation an extrusion vendor recommended a Low Density PE (LDPE) with an Melt Flow Index of 0.8 (190°C, 2.16kg) to meet the backing layer thickness specification and the requirement that the backing layer be compat ible with the fabrication method while still attached to the working layer polyurethane.

[0177] In one variation of the method, the flat sheets of thin film material are formed into a device sections by the thermoforming process. As shown in FIG. 19A, thermoforming is a manufacturing process where heat is applied to a polymeric sheet. The heat makes the material malleable so it can conform to a mold to take the shape of a mold. In one variation of thermoforming, a vacuum is introduced between the polymeric sheet and the mold to draw the sheet around the mold. In another variation, pressure thermoforming may be used, wherein the polymeric sheet is pushed into the mold by excess pressure on the side of the polymeric sheet away from the moid, as shown in FIG. 19B. In both variations, the polymeric sheet is forced to conform to the mold by a differential gas pressure between the "mold side" of the sheet and the "non-mold side" of the sheet, wherein the difference between vacuum and pressure thermoforming is how the differential air pressure is generated. A known benefit of vacuum thermoforming is that the polymeric sheet forms its own seal against the mold so the higher atmospheric pressure pushes it against the mold, while a known benefit of pressure thermoforming is that the polymeric sheet can be pressed down more firmly against the mold, causing it to better match small details and short radius bends.

[0178] In accordance with standard practice, thermoforming is typically performed on the freestanding PU layer, which would normally require striping away any backing layers prior to the forming operation. However, the inventors have discovered that for some polymeric working layers the efficiency and productivity of this device fabrication method is improved when one or both polymeric backing layers are left attached to the working layer during the thermoforming operation. Further, this inventive method of fabrication includes maintaining one polymeric backing layer on each device section through throughout the fabrication method, as will be described below.

[ 179] It has been discovered that the thermoforming operation can be performed on the PU material in all three variations - one, two, and three layers. However, to perform the later, joining, step, discussed below, the material must have one surface of the PU exposed on each device section for the joining process to succeed. Thus, if the material comprises two backing layers disposed on opposite surfaces of the working layer, one of the two backing layers may optionally be removed from the working layer, as illustrated in FIG. 16, prior to thermoforming, leaving a two layer material to be formed. If the second PE backing layer is left in place during

thermoforming it will need to be removed prior to the joining process, as discussed below.

[0180] The next step in the fabrication method is forming the film material into device sections. As is well known in the art, thermoforming comprises two major substeps; holding the film material in an open frame while heating it to below the melting point but above the heat distortion temperature (HDT) and using differential air pressure to pull or push the softened film into and/around a shaped mold. The film is allowed to cool on the shaped mold to below the HDT before being removed from the mold. The HDT of a material (or a similar measure, the Vicat softening temperature) is determined by the following test procedure defined by the ASTM

International [ formerly the American Society for Testing and Materials]. As a practical matter, the proper temperature for thermoforming the polymeric materials selected for fabricating temporary implants within the body is best determined by conventional process development tests using the materials as-delivered by the film supplier. The cooled, formed film material comprises one device section.

[0181] As illustrated in cross-section in FIG. 17A, an exemplary thermoforming mold for making a temporary, balloon-like implant for deployment in the body comprises a hemi-ellipsoidal concavity in a gaseously porous block, where the gaseously porous block is disposed on a vacuum plenum whereby the reduced pressure in the plenum is transmitted to the surface of the hemi- elliptical concavity. Implants, and the mold that is used to fabricate them, can assume other shapes. Further, the thermoforming mold can be convex instead of concave. It will be noted that thermoforming can be performed with a multi-mold gaseously porous block, thereby speeding production.

[0182] As illustrated in FIG. 17B 1 and 1 7B2 respectively, the thin film material may be disposed in two orientations during vacuum forming. In FIG. 1 7B 1 the material is disposed working layer up. That is, the one backing layer is deployed so that it is in direct contact with the gaseously porous block. For convenience, a thermoformed item fabricated on a concave mold with material in this orientation is referred to as concave herein. In FIG. 17B2 the material is disposed working side down. That is, the one backing layer is deployed so that it is not in contact with the gaseously porous block. For convenience, a thermoformed item fabricated on a concave mold with material in this second orientation is referred to as convex herein.

[0183] It may be noted that in other variations of the method the mold is convex. When a convex mold is employed the orientations of the co-extruded material for making the concave and convex device sections are reversed. That is, for example, a thermoformed item fabricated on a convex mold with the backing layer in direct contact with the gaseously porous block is referred to as a convex section.

[0184] In other variations of the method the mold comprises a dual mold having both a concavity and a convexity displaced a convenient working distance apart. FIG. 17C illustrates in cross- section an example of such a mold. The thin film material may be disposed in either of the two orientations discussed above - backing layer up or backing layer down - during thermoforming with this dual mold. With either orientation the dual mold produces both a concave and a convex device section simultaneously.

[0185] In another variation of the method the second backing layer is left in place during thermoforming, in which case there is only one "orientation^" since both sides of the working layer are covered by a backing layer.

[0186] In all variations of this method the working layer is thermoformed with one or two backing layers attached. Successful thermoforming requires that the I I DT properties of both the working layer and the backing layer(s) be similar so that one layer does not melt when the other layer is at the HDT.

[0187] Returning to FIG. 17A, it will be noted that the exemplary concave hemi-ellipse mold also allows for a flat band or flange region running circumferentially about the rim of the concavity. This flange region is simply a flat area surrounding the actual shaped mold. In most implementations the exterior form of the gaseously porous block and the frame holding the unprocessed sheet of material are oversized rectangles, that is, bigger than the concavity, leaving a significant flat area to provide the flange region as well as scrap area that is convenient for handling purposes.

[0188] A device is fabricated by joining two device sections. Optionally, an access hole may be cut in at least one of the two device sections to allow the joined sections to be inverted, that is, for the joined sections to be turned inside out. In some variations of the device the access hole is generally circular with a diameter on the order of one quarter to one half the diameter of the hemi- ellipsoid. In one embodiment the access hole is approximately 25 millimeters in diameter. In some variations of the method a die cutter is used to cut the access hole.

[0189] The cross-sectional illustration in FIG. 18A shows two device sections nested in preparation for joining, for example, by of RF welding. It will be noted that the two nested device sections comprise one convex section nested in one concave section, this combination disposing the two working layers in direct contact, that is, with no backing layer between them, which is required for joining by RF welding or alternative joining methods. However, one backing layer on the exterior of each device section is left in place during joining. It will be further noted that ail joining methods require the device sections to comprise the working layer and only one backing layer. Therefore, if two backing layers were left on the working layer during the forming step one must be removed prior to the joining step.

[0190] If thermo forming has been performed using the dual mold illustrated in FIG. 17C then the two device sections on the one sheet of material can be nested in preparation for joining. Nesting is easily performed by folding the sheet with the working layer on the interior side of the fold such lhat the convex section fits into the concave section, as illustrated in the schematic cross-section of FIG. 18B.

[0191] In some variations the device sections may not be rotationally symmetric or in the case of two concave sections, as was illustrated in FIG. 14, the two device sections may not nest, where nesting provides automatic lateral alignment. In these variations the method must include an explicit step of aligning the two device sections.

[0192] It will be noted that the optional access hole, not illustrated, is typically, but not necessarily, cut into a device section before nesting and joining. [0193] After alignment, the two device sections are joined. In one variation they are joined by RF welding while in other variations they can be joined by any of the well-known means of joining two layers of polyurethane such as those techniques described in

http://w^fww.mddionline.com/article/po

included as Appendix A herein. RF welding is a form of dielectric heating. As such, the materials to be joined by RF welding must be poor conductors of electricity, since a good conductor would act as a short circuit, weakening the field near the conductor. The PU working layer is amenable to RF welding whereas the PE backing layer is not responsive to the process, allowing the method to keep the backing layer in place during RF welding.

[0194] The RF process generates radio-wave power, which causes molecules within the material to be agitated. As a result, heat is generated within the material, allowing adjacent plastic materials to melt and exchange molecules, thereby bondin the materials. When the power to the RF-energy generator is shut off, the melted plastic resolidifies, resulting in a uniform weld that is as strong or stronger than the materials being bonded together.

[0195] An electrode, or die, machined in the shape of the region to be joined is used to apply power to the device sections. In the present process, the region to be joined is the flange around the formed body of the device sections. When the two flanges are joined they form a fluid-tight sealed seam.

[0196] In some variations optional device subcomponents, for example, a t nnel valve, are sealed into the seam 1004. In some instances these subcomponents are disposed into an opening left in seam 1004 during the joining step and sealed therein in a secondary joining operation performed after the device has been inverted, as was described above with reference to FIG. 4. In other variations of the fabrication method, as shown schematically in a plan view in FIG. 20A and an exploded side view in FIG. 20B, one or more of these subcomponents, a tunnel valve in the figure for illustrative purposes, are disposed between the two working layers and can be RF welded or otherwise joined into seam 1004 simultaneously as the seam is sealed. For the sake of clarity the two working layers are shown as crumpled, rather than nested, hemi-ellipses in the figure. In the figure the tunnel valve is a completed subassembly; although it is possible to seal the seams of the tunnel val ve in the same process step as this device section joining step, such a combined process is typically not used. It will be noted that an isolating material, for example Teflon©, is disposed in the central lumen of the tunnel valve during the RF welding process to prevent the lumen from being sealed shut. The isolating material is not part of the valve but is required during the joining step when two parts must be prevented from being joined by a heating-type joining process.

[ 1 7] In other variations these optional device subcomponents may be designed to be an integral part of the device section(s), as was discussed above with reference to FIG. 14. In one variation of the joining process depicted in that figure, it is shown that the integration of the valve upper layer 341 and lower layer 342 into the device surface material is accomplished by configuring the machined electrode for RF welding to form a pair of seams projecting in an outwardly radial direction relative to the nominally circular flange/seam around the device sections. These projecting seams are formed in the aforementioned 11 at. otherwise scrap, area beyond the designed peripheral flange of the device section and are disposed generally parallel to each other and spaced by a gap substantially equal to the desired diameter of central lumen.

[0198] When the seam 1004 is sealed with the RF welding process, these parallel valve seams are sealed as well. In other variations of the method in which RF welding is not used for joining the device sections together, equivalent modifications to the joining process can be made to incorporate the optional device subcomponents.

[0199] After the joining step is complete the device is trimmed along a trim line to remove excess material around the external seam, that is, the material outside the designed, sealed flange/seam. FIG. 14A illustrates an exemplary trim, line 1006 around a device with an integral tunnel valve. In some variations a die cutter is utilized. In other variations some or all of the excess material may be trimmed prior to the joining step.

[0200] Additionally, in some variations of the method, after the joining step is complete and either before or after the excess material around the external seam is removed, any remaining backing layer material is removed. In variations in which the device is completed at this step the backing layer may be left in place for protective purposes until a convenient time but in no case later than deployment in a patient. In variations of the device in which an access hole has been cut in one or both of the device sections, the device may be inverted by turning the device inside out through an access hole. In this variation the backing layer must be removed before inversion. Inverting the device converts the external seam, which may irritate bodily organs when the temporary implant device is deployed, into an internal seam whereby the device presents a smooth exterior to the bodily tissue to which it comes in contact. [0201] With the device inverted, a patch of material sized and shaped to seal the access hole is joined to the device using RF welding, gluing or other means of joining. In al l variations, appropriate shielding/isolating steps must be employed to prevent the upper and lower device sections from accidentally being joined the at the location of the access hole along with the access hole patch.

Claims

CLAIMS e believe our invention to be:

1. A method of manufacturing expandable devices, comprising the steps of:

providing a multi-layer thin film of polymeric material, the multi-layer thin film of polymeric of material comprising a thin film backing layer and a thin film working layer and, wherein the first thin film backing layer is disposed on a first side of the thin film working layer;

positioning the multi-layer thin film on an open frame and heating the multi-layer thin film;

forming the multi-layer thin film into a device section having a predetermined shape using differential gaseous pressure to conform the multi-layer thin film to a mold, the device section having an inner surface and an outer surface, one backing layer comprising the outer surface, the predetermined shape having a flat flange region;

disposing a first device section together with a second device section such that the working layers of the first and second device section are juxtaposed with the flange region of the first device section being in alignment with the flange region of the second device; creating an access hold in at least one of said two device sections;

joining the flange regions of the device sections to form a fluid tight seam around the entire flange;

trimming an excess material from around the flange region; and

inverting the device though the access hole.

2. The method of claim 1 where the step of forming the film into a device section comprises the step of forming a convex and a concave device section.

3. The method of claim 2 where the step of forming a convex and a concave device section comprises using a dual mold to produce the convex and the concave device sections simultaneously.

4. The method of claim 1 , further comprising a second thin film backing layer disposed on a second side of the thin film working layer.

5. The method of claim 5, further comprising removing the second backing layer before heating the muli -layer thin film.

6. The method of claim I , further comprising cutting an access hole through at least one device section, the hole disposed to avoid intersection with the flange region.

7. The method of claim 1, further comprising exposing one side of the working layer by

removing a backing layer.

8. The method of claim 1, further comprising disposing an additional device subcomponent between the aligned working layers of the first device section together and the second device section.

9. The method of claim 1, wherein joining the flange regions of the device sections comprises joining by thermal, mechanical, or chemical joining.