Patent Description:
A fluid control valve for controlling fluid flow in a medical balloon or in other fluid-filled devices according to the preamble of claim <NUM> is known from <CIT>. Furthermore, other fluid control valves are known from <CIT> and <CIT>.

According to <NUM> World Health Organization data, <NUM> million Americans over the age of <NUM> are above target weight. Of these individuals, <NUM> million are considered overweight (<NUM><Body Mass Index<<NUM>) and <NUM> million are considered obese (Body Mass Index ><NUM>). Worldwide, more than <NUM> billion adults age <NUM> and over are overweight, and <NUM> million are obese. Obesity places patients at increased risk of numerous, potentially disabling conditions including type <NUM> 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 (>= <NUM> years of age). On average, men and women who were obese at age <NUM> live <NUM> and <NUM> fewer years, respectively, than their healthy weight peers.

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.

One less-invasive intervention that has begun to gain popularity is an intragastric balloon. Intragastric balloons in their uninflated state can be placed endoscopically or positioned using other methods and, once in place, are typically filled with a filling fluid through a thin catheter or conduit extending up the esophagus from the device in the stomach to an external fluid supply. This catheter is then removed from the device and extracted from the body through the esophagus. Upon removal of the catheter, the catheter system must seal the fluid communication between the interior of the device and the gastric environment to maintain the balloon in its filled state for the proscribed time.

In some gastric balloons an endoscopic procedure is used to remove the balloon at the end of its proscribed time. Endoscopic procedures, while generally safe, inherently carry some risk to the patient, are invasive, require the patient to visit an endoscopy facility, and require the services and costs of an endoscopist. For these reasons various self-opening or non-invasively-triggered fluid release mechanisms or valves have been developed.

In particular, several self-opening release valves, as described in the following commonly assigned patents, publications, and provisional applications :<CIT> (ALLR-N-Z003. <NUM>-USS); <CIT> (ALLR-N-Z003. <NUM>-USX); <CIT> (ALLR-N-Z004. <NUM>-USS); <CIT> (ALLR-N-Z003. <NUM>-USS); <CIT> (ALLR-N-Z003. <NUM>-USS); <CIT> (ALLR-N-Z020. <NUM>-USS); <CIT> (ALLR-N-Z004. <NUM>-USS); <CIT> (ALLR-N-Z003. <NUM>-USS); <CIT> (ALLR-N-Z020. <NUM>-USS); <CIT> (ALLR-N-Z026. <NUM>-US); and Provisional Application Nos. <CIT> <CIT>. In addition, the valves described herein can be used with the devices described in the forgoing patents, publications and provisional applications.

However, in certain applications there may be a need for a device to rapidly deflate. Therefore, there remains a need for devices where a fluid release flow rate is increased to assist with fast deflation of the device. For instance, there also remains a need for a self-releasing valve that opens rapidly to its full open state.

The present invention provides for a fluid control valve as defined by claim <NUM>, wherein preferred embodiments of the invention are laid down in the dependent claim. In particular, the invention relates to self-opening release valves for emptying balloon-like devices. More particularly the invention relates to self-opening valves that open rapidly after initiation of the opening process, where self-opening generally implies no direct human action. In some variations, the valves can achieve full aperture opening in a rapid manner.

The present disclosure includes fluid release mechanisms for use with fluid filled devices and are especially useful in gastric balloons for occupying a space within the patient's body. In one example such a medical device includes a fluid 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 fluid filler material within the interior reservoir; a fluid path for evacuation of the fluid, a plug for sealing the fluid path, an energy storage element disposed to remove the plug from the fluid path, and a release material disposed to hold the plug in a sealing configuration in the evacuation path until the strength of the release material degrades below that which is needed to resist the energy storage element.

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 device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments and variations without departing from the scope of the invention as defined by the claims.

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. Of the drawings:.

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 conjunction with a gastric balloon device, the devices, methods, and systems of the present disclosure can be can be used with other fluid-filled devices or systems where automatic release of the fluid in the device or system might be required or beneficial or where automatic release of the fluid between any two separated spaces in which unassisted (that is, without direct human manipulation or intervention) opening of a fluid passage between the two spaces is desired.

<FIG> illustrates schematic block diagram of an exemplary fluid fillable balloon device; in particular, it illustrates a gastric balloon device assembly <NUM>. <FIG> is an illustration of device <NUM> in place in a patient's stomach after it has been inflated but before the filling tube has been removed. The device generally comprises two states of interest: a pre-deployment or uninflated configuration and a deployed, inflated or active configuration; the deployed configuration is shown. Generally, the device is inflated with a fluid delivered through a tube <NUM>, also referred to herein as a catheter or conduit, wherein the tube may pass through a lumen in the wall of the balloon device or is coupled to a fluid path <NUM> between the exterior and the interior of the balloon device. In certain balloon devices the wall <NUM> of the balloon is fabricated from a thin film material such as, for example, polyurethane. In some variations the tube comprises a balloon end or internal section 110A that extends through fluid path <NUM> into the central enclosed space or reservoir <NUM> of device <NUM>. In other variations internal section 110A stops short of the reservoir <NUM>. The conduit <NUM> can be removed from the device once inflation is completed or after partial inflation. When the conduit is removed, fluid path <NUM> must be sealed to prevent the inflation fluid from leaking out, where sealing is accomplished by fill valve <NUM>, illustrated in <FIG>, which may comprise an external section 113B, an internal section 113A. In some variations, elements of the fill valve <NUM> have components installed inside conduit <NUM> as well as in fluid path <NUM>. Other variations of the balloon device may be self-inflating, wherein, for example, two reactive chemicals pre-stored inside the uninflated balloon combine once the balloon is in place. The combined materials, such as an acid and bicarbonate of soda, give off a gas that inflates the balloon.

It is typically the case that release valve <NUM> is a single-use device; that is, once it opens to release fluid it cannot close, or at least is not closed, again. In some variations, as illustrated in <FIG>, the valve may comprise a patch <NUM> of degradable material, which degrades or opens when exposed to either the natural stomach fluids or the filling fluid contained within reservoir <NUM>. Once patch <NUM> degrades, the filling fluid is free to escape into the patient's stomach. In certain cases, the degradation rate of the patch, and the resulting flow rate, cannot be controlled adequately. The release valves described herein improve the timing and adequacy of the flow rate of the release of filler fluids by controlling the degrading fluid and by providing a.

<FIG> is an exemplary mechanical schematic diagram of a fluid control valve system <NUM> that has a binary flow condition or operation, where "binary" indicates that the valve comprises an open state and a closed state. Where in the closed state the valve is closed to either fully or significantly prevent fluid flow. In the open state, the valve allows partial or maximum fluid flow. It will be understood that a mechanical schematic diagram is a simplified representation of the functional components of a mechanical system and the mechanical relationship therebetween. It does not necessarily represent the physical forms of the mechanical elements nor the physical layout, attachment, or configuration of any actual components.

Returning to <FIG>, the binary operation of control valve system <NUM> is achieved through the addition of an energy storage device disposed to force the valve to the fully open condition. , a valve system <NUM> is disposed between two otherwise isolated spaces, spaces <NUM> and <NUM>, at least one of which contains a fluid 415A. In some variations the second space also contains a fluid 415B. In this variation, a valve system <NUM> includes three core mechanical components. The main component is a valve mechanism <NUM> that blocks or unblocks the flow of fluid from one space to the other. Schematically in <FIG> valve mechanism <NUM> is depicted as comprising a two element gate (<NUM>, <NUM>), where one element of the gate is a base <NUM> and a second element is a traveler <NUM> where traveler <NUM> and base <NUM> abut tightly enough to block the flow of any fluid 415A/415B through valve mechanism <NUM>. Note again that a mechanical schematic only represents functional elements and is not intended to indicate the physical form of the element effecting that function.

As further illustrated, valve system <NUM> comprises a second core component, an energy storage device <NUM>, for example a spring, where the energy storage device is disposed to move traveler <NUM> away from base <NUM>. In the schematic a base support <NUM> and a head <NUM> have been included to schematically illustrate a connection between energy storage device <NUM> and valve mechanism <NUM>. In the normal operation of valve system <NUM>, energy storage device <NUM> is initially in a high energy storage configuration and disposed between head <NUM> and base support <NUM> with a distance D1 between head <NUM> and base support <NUM>. The compressed energy storage device <NUM> generates a force F directed to push traveler <NUM> away from base <NUM>, as indicated by the arrowheads at the ends of spring <NUM>. Energy storage device <NUM> does not need to be attached to either head <NUM> or base support <NUM> (or, equivalently base <NUM> or traveler <NUM>). Alternatively, one or both sides of the device can be connected to the respective adjacent head <NUM> or base support <NUM>.

The third core component of a valve system <NUM> is a restraining element <NUM>. Under normal initial operation of valve system <NUM>, restraining element <NUM> is also disposed between head <NUM> and base support <NUM>, where restraining element <NUM> is in tension T which holds head <NUM> and base support <NUM> from moving apart, as indicated by the arrowheads showing the forces felt by head <NUM> and base support <NUM>.

Valve system <NUM> switches between the no-flow condition, shown schematically in <FIG>, and the full-flow condition, shown schematically in <FIG>, when restraining element <NUM> loses its ability to to counteract the force F of energy storage device <NUM>. Depending on the designer's needs, restraining element <NUM> can be designed to lose strength by changing its temperature, by hydrolysis, by dissolution, by oxidation, or by any means appropriate for the restraining material and operational environment. Typically restraining element <NUM> breaks when the spring force exceeds the remaining strength of element <NUM>, as illustrated in the figure, but element <NUM> may also lose its ability to maintain the required tension if it plasticly deforms, that is, stretches permanently, or elastically deforms.

As shown in <FIG>, the failure of restraining element <NUM> allows energy storage device <NUM> to increase the distance between base support <NUM> and head <NUM> to D2, thereby allowing fluid flow through valve mechanism <NUM> as shown by the arrows. In <FIG>, head <NUM>, traveler <NUM>, and a portion of restraining element <NUM> no longer have a connection to base support <NUM> indicating that those parts of fluid control valve system <NUM> are free to float away by a distance greater than D2. In other variations energy storage device <NUM> may be attached to head <NUM> instead of base support <NUM> while in yet other variations energy storage device <NUM> may connect head <NUM> and base support <NUM> even after opening, in which case D2 is the length of energy storage device <NUM> in its low energy condition (e.g., no longer in compression). In yet other variations energy storage device <NUM> is not physically attached to either base support <NUM> or head <NUM>, in which case it may become a free-floating element once the constraining tension of restraining element <NUM> is removed.

As was noted above, mechanical schematic diagrams are not intended to suggest or describe actual embodiments of the mechanical system; they only explain the mechanical functional relationships in the mechanical system. For example, <FIG>, <FIG>, and <FIG> are alternative mechanical schematics of the same fluid control valve system as depicted in <FIG>. <FIG> illustrate a variation in which base <NUM> and traveler <NUM> sandwich energy storage device <NUM> between themselves directly (that is, the spring sits between the two portions and directly bears on them to move them apart) while restraining element <NUM> is directly or indirectly attached to the exterior of the "sandwich" to hold base <NUM> and traveler <NUM> tightly together, compressing energy storage device <NUM>. The mechanical schematic of <FIG> illustrates the after-release mechanical relationships of the elements in the schematic of <FIG>.

<FIG> illustrates schematically a variation of the valve system in which base <NUM> is in the form of a fluid path <NUM> which channels fluid <NUM> between the isolated spaces <NUM>, <NUM>. Traveler <NUM> forms a plug or stopper that blocks fluid path <NUM> when the valve system is in its normally closed condition. Drawn in this fashion, the mechanical schematic of <FIG> helps clarify the use of a control valve system <NUM> in fluid filled balloon applications an embodiment of which is discussed below.

In some variations of control valve system <NUM> it is possible to combine two or more functions into one physical element. As shown schematically in <FIG> and <FIG>, in this variation the base, traveler, and restraining element are all embodied in a single close-ended tube <NUM>. Initially, tube <NUM> is a sealed fluid path between spaces <NUM> and <NUM>.

Energy storage device <NUM> is disposed to apply a force that is directed to pull the two ends <NUM>, <NUM> of tube <NUM> apart. The two ends do not move apart while the walls of tube <NUM> remain strong enough to withstand the applied force. When the restraining element loses strength, as it is designed to do in specific environments, it will eventually allow the spring to pull tube <NUM> into two pieces, forming traveler <NUM> and base <NUM> and essentially allowing flow through the base support <NUM>, as shown in <FIG>.

In yet another variation of valve system <NUM>, not illustrated, base <NUM> and traveler <NUM> may comprise two jaws of a hinged component, with energy storage device <NUM> acting to open the hinge and restraining element <NUM> holding the hinge closed until element <NUM> loses strength as designed.

Other variations, also not illustrated, include energy storage devices in which the energy is stored by holding the device in an expanded, rather than compressed state.

<FIG> is an exploded view of one variation of valve system <NUM> with an exterior energy storage device <NUM> in the form of a coil spring, where exterior indicates the spring <NUM> is exterior to the flow path through the valve system <NUM>. In this variation, valve <NUM> of <FIG> comprises traveler <NUM> in the form of a plug or pin, base <NUM> in the form of a socket into which plug <NUM> is inserted, and a compliant gasket <NUM> that surrounds plug <NUM> to ensure a snug and leak-proof fit when plug <NUM> is inserted into socket <NUM>.

As further illustrated in <FIG> and sectional view <FIG>, this variation of valve system <NUM> also comprises energy storage device <NUM> implemented as a coil spring disposed between a spoked head <NUM> and a substantially identical spoked base support <NUM>, wherein restraining element <NUM> is a suture-like release material that is looped or stitched between the spokes of head <NUM> and base support <NUM>. Head <NUM> and base support <NUM> each have a central hole large enough to accommodate plug <NUM> surrounded by gasket <NUM>. In this variation release material <NUM> is stitched in a pattern to minimize tilting of head <NUM> relative to base support <NUM> both before and after initial release material breakdown.

As shown in the figures, in this variation plug <NUM> comprises an extended body 412A with a larger diameter pinhead 412B at one end, where the length of the extended body is designed to be longer than the length of the compressed coil spring <NUM> plus the thicknesses of the head <NUM> and base support <NUM>, and the diameter of pinhead 412B is designed to be larger than the hole in head <NUM> to prevent plug <NUM> from fully entering or passing through the hole in head <NUM>. The spring, head, base support, and release material comprise a valve release subassembly <NUM>.

In this variation socket <NUM> is essentially a cylindrical tube disposed between the two spaces comprising a central lumen that allows fluid flow between the two spaces. In many variations socket <NUM> is fabricated as a socket subassembly <NUM> that allows the socket to be attached to the wall <NUM> separating the two spaces, as will be described below.

This variation of valve system <NUM> is assembled by inserting plug <NUM> (with gasket <NUM>), through the lumen in valve release subassembly <NUM> formed by the open central region of coiled spring <NUM> such that a tip <NUM> of plug <NUM> extends beyond the end of valve release subassembly <NUM> by a designed length. As further illustrated in <FIG> and <FIG>, the exposed tip <NUM> of plug <NUM>, surrounded by gasket <NUM>, is subsequently inserted into socket subassembly <NUM>, where the gasketed tip <NUM> seals the lumen in socket subassembly <NUM> against fluid flow. In some variations tip <NUM> of plug <NUM> is bulbous to compress gasket <NUM> against the innermost surface of socket assembly <NUM> while providing a leading edge that guides tip <NUM> into the lumen.

As shown in <FIG> and in perspective view in <FIG>, valve system <NUM> can be installed to control fluid flow between two spaces separated by a wall <NUM> of thin film material. While <FIG> and <FIG> suggest the use of a valve system <NUM> to release fluid from a gastric balloon fabricated from thin film material, this is but an exemplary use. The valves described herein may be used in any situation where there is a fluid impervious barrier material separating two spaces and where fluid may be present on either or both sides of the barrier material. For example, a valve system <NUM> can be used to temporarily separate two reactive chemicals where one chemical is in fluid form.

As illustrated in <FIG>, socket subassembly <NUM> is attached to wall <NUM>, through which a hole is provided for fluid flow. There are several ways to attach socket subassembly <NUM> to a wall, for example gluing or welding, where the preferred method of attachment is an engineering decision based, among other considerations, the material properties of wall <NUM> and socket assembly <NUM>. In the illustrated variation, where wall <NUM> is a thin polymeric sheet, mechanically attaching socket assembly <NUM> is used for example. In this variation socket assembly <NUM> comprises three parts; a retaining ring <NUM>, a wall anchor <NUM>, and a gasket jacket <NUM>.

Gasket jacket <NUM> is a thin-walled, hollow cylinder. The inner wall of the hollow cylinder is sized, and sometimes shaped, to grip the compliant, gasketed tip <NUM> of plug <NUM>. For example, the inner wall may be tapered to have a wider opening to accept plug <NUM> and to guide the tip <NUM> into a narrower portion wherein the compliant gasket is squeezed to make a tight fit. The inner wall may be inscribed with a number of circumferential ridges and grooves to better grip the compliant gasket. Or for example, in some variations, the inner wall may have an indented groove with a circular segment cross-section that matches the bulbous tip <NUM> of the gasketed plug; this groove acts a detent to provide a positive hold on tip <NUM>.

Wall anchor <NUM> is the primary means to attached gasket jacket <NUM> to a thin-film wall <NUM>. It is used to pinch a shaped section of wall <NUM> against the exterior of gasket jacket <NUM>. This pinching behavior is illustrated in the exploded, cross sectional view of socket assembly <NUM> of <FIG>. The wall section starts out as a flat sheet but takes on the illustrated "stovepipe hat" shape after being stretched over a mandrel. Gasket jacket <NUM> is then inserted inside the wall section, most easily from the "brim" side of the stovepipe hat while wall anchor <NUM> is slipped over the exterior of the "pipe" section of the stovepipe, thereby trapping the wall material between jacket <NUM> and anchor <NUM>. In many variations anchor <NUM> is fabricated from a soft material, for example a plastic, and toleranced to enclose the wall material without pulling or tearing it. Finally, a retaining ring <NUM> is placed over anchor <NUM> to squeeze it tightly against wall material <NUM>, pinching the material against gasket jacket <NUM>.

<FIG> illustrates one method for inserting plug <NUM> (with valve release subassembly <NUM> in place) into a socket assembly <NUM> that has been pre-installed in a wall <NUM>. As shown, gasket <NUM> is extended by a convenient length to form a gasket extension 427A that extends a convenience distance beyond plug tip <NUM>. This extended length 427A is not filled by any solid and can easily be threaded through the lumen in gasket jacket <NUM>. A portion 427B of gasket extension 427A emerges through the lumen in gasket jacket <NUM> on the opposite side of wall <NUM> from plug <NUM>. Gasket extension 427A moves with relative ease through gasket jacket <NUM> because there is no plug inside this portion of the gasket. Tip <NUM> of plug <NUM> is drawn into gasket jacket <NUM> by pulling on gasket extension 427B until tip <NUM> is captured by jacket <NUM>. By design, tip <NUM> and the gasket around it cannot pass fully through the lumen, so continuing to pull on gasket extension 427B creates an increasing tension on gasket <NUM>.

When the elastic limit of gasket <NUM> is reached, the gasket tears into two sections. In some variations a preferential detachment point <NUM> is created in gasket <NUM> by weakening the gasket at a pre-determined location by partially cutting through the gasket, creating a circumferential score, or otherwise weakening the gasket at the desired location. Typically, the desired location separates gasket <NUM> from gasket extension 427A. Using a preferential detachment point created by weakening the gasket allows the designer to control how much force is required to tear the gasket, where the tear will be, and ensure a clean tear between the removed portion of the gasket and the gasket surrounding tip <NUM> to seal the valve.

For the illustrated variation, the valve is installed in a fluid impervious wall <NUM> separating two spaces on either side of the wall, where at least one space has a fluid. Plug <NUM> substantially fills the lumen in gasket jacket <NUM> and presses gasket <NUM> against the inner wall of the lumen in gasket jacket <NUM> to seal the lumen against fluid transfer. For convenience, the space in which release valve subassembly <NUM> is located will be designated as first or interior space and is bounded by wall <NUM>. By design, release material <NUM> is susceptible to deterioration when exposed to the environmental conditions in the interior space. In many variations the release material is filamentary. Examples of release materials that are available in filamentary suture form can include Polyglycolide (PGA), Polydioxanone (PDS), Poly(lactic-co-glycolic acid) (PLGA), Polylactide (PLA), Poly (<NUM>-hydroxybutyric acid) (P4HB), Polyglactin <NUM>, and Polycaprolactone (PCL). In some variations the interior space may be filled with a fluid which, over a designed period of time, dissolves or hydrolyses the suture. In other variations, for example, release material <NUM> may be melted or softened by increasing the temperature in the interior space.

Claim 1:
A fluid control valve for controlling fluid flow in a medical balloon or in other medical fluid-filled devices, the valve comprising:
a base (<NUM>) defining a fluid path (<NUM>) therethrough such that the fluid path (<NUM>) is fluidly coupled between a first space and a second space;
a traveler structure (<NUM>) coupled to the base (<NUM>);
an energy storage device (<NUM>) disposed between the traveler structure (<NUM>) and the base (<NUM>); characterized by
a restraining element (<NUM>) that restrains the energy storage device (<NUM>) in a stored energy condition, where the restraining element (<NUM>) is configured to degrade such that degradation of the restraining element (<NUM>) releases the energy storage device (<NUM>) from the stored energy condition to move the traveler structure (<NUM>) away from the base (<NUM>).