Patent Description:
The gastrointestinal (GI) tract may require treatment for various reasons including perforations, bleeding defects, post-surgical leaks, or other wounds of the tract. However, limited treatment options exist for managing such wounds. Options include surgical re-operation, which is relatively invasive and may have high morbidity and mortality rates. Thus, endoscopic delivery of a treatment aid may be a less invasive and more effective option, promoting natural healing of tissue.

<CIT> discloses systems and methods of delivering a patch to a target site of a patient. The patch may comprise a biomaterial such as chitosan or extracellular matrix and may be biocompatible and/or bioresorbable. The system may include an endoscope, a patch, and one of an instrument or a cap, the patch being coupled to the respective instrument or cap and detachable therefrom. Methods of delivering the patch to the target site may include introducing an endoscope into a gastrointestinal tract of a patient, e.g., the patch being in a folded or crimped configuration, navigating a distal end of the endoscope proximate a target site; and applying the patch to the target site while releasing the patch from the endoscope.

<CIT> discloses methods and materials for closing an opening (e.g., an incision) within a mammal. For example, methods and materials for closing a transluminal incision created during a natural orifice transluminal endoscopic surgery are shown.

The presently claimed invention provides a medical device according to claim <NUM>. Further developments of the herein claimed invention are described in the dependent claims.

According to an example, a medical device may comprise a first tube, a second tube configured to sheath at least a portion of the first tube and configured to translate along a length of the first tube, an expandable device at a distal portion of the first tube, the expandable device having a collapsed state and an expanded state, a patch surrounding at least a portion of an outer surface of the expandable device, and a connector for holding the patch to the expandable device when the second tube covers the patch and the expandable device and for releasing the patch from the expandable device after the second tube uncovers the patch and the expandable device.

In another example, the first tube may include a lumen in fluid communication with the expandable device to supply a fluid to the expandable device. The connector may extend longitudinally along a portion of the expandable device. The connector may comprise a folded sheet forming a first half of the folded sheet and a second half of the folded sheet, wherein the first half of the folded sheet is attached to the expandable device, and the second half of the folded sheet is attached to the patch. The second half of the folded sheet may include a first surface adjacent to the first half of the folded sheet and a second surface adjacent to the patch, wherein the second surface is attached to the patch. The first half of the folded sheet may be attached to the expandable device via an adhesive, and the second half of the folded sheet may be attached to the patch via a soluble adhesive. The soluble adhesive may be configured to dissolve when the second tube uncovers the patch and the expandable device, and the patch may be exposed to a solvent, thereby releasing the patch from the connector and the expandable device.

In another example, the medical device may further comprise a wire, wherein a distal end of the wire is coupled to a distal portion of the first tube, the wire is sutured through the patch and the connector, and the wire extends proximally through a lumen of one of the first tube and the second tube. The wire may be sutured linearly through the patch and the connector, along a longitudinal length of the connector. The connector may include a plurality of openings configured to receive the sutured wire. A proximal end of the wire may be configured to be pulled so that the wire translates proximally, thereby removing the wire from the patch and the connector. The distal end of the wire may be removably secured to the distal portion of the first tube via a heat shrink or a crimp. The proximal end of the wire is coupled to an actuator configured to pull the wire proximally.

In another example, the connector may comprise a soluble adhesive directly between the patch and the expandable device, and the soluble adhesive is configured to dissolve when the second tube uncovers the patch and the expandable device and the soluble adhesive is exposed to a solvent, thereby releasing the patch from the expandable device. The patch may comprise chitosan and/or a chitosan modified material.

According to another example, a medical device may comprise a tube, an expandable device at a distal portion of the tube, the expandable device having a collapsed state and an expanded state, a patch surrounding at least a portion of an outer surface of the expandable device, the patch being removably attached to the expandable device via a connector. The medical device may further comprise a wire suturing a portion of the connector to the patch, wherein the wire extends proximally along a length of the tube, and a proximal portion of the wire may be coupled to an actuator. The actuator may comprise a knob or a switch configured to pull the wire proximally, thereby removing the wire from the patch and the second half of the connector. The actuator may be positioned on a proximal portion of the tube.

According to an example, a method of treating a subject may comprise introducing a medical device into a gastrointestinal system of the subject, positioning a distal end of the medical device within a body lumen of the subject, wherein the distal end of the medical device includes an expandable device, a patch removably coupled to an outer surface of the expandable device, and a connector for holding the patch to the expandable device, retracting an outer sheath to expose the expandable device and the patch, supplying a fluid to the expandable device, such that the expandable device expands and the patch contacts a tissue surface of the bodily lumen, and releasing the patch from the expandable device.

Reference will now be made in detail to aspects of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same or similar reference numbers will be used through the drawings to refer to the same or like parts. The term "distal" refers to a location or portion of a medical device farthest away from a user of the device, e.g., when introducing a device into a subject (e.g., patient). By contrast, the term "proximal" refers to a location or portion closest to the user, e.g., when placing the device into the subject.

Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the features, as claimed. As used herein, the terms "comprises," "comprising," "having," "including," or other variations thereof, are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements, but may include other elements not expressly listed or inherent to such a process, method, article, or apparatus. In this disclosure, relative terms, such as, for example, "about," "substantially," "generally," and "approximately" are used to indicate a possible variation of ±<NUM>% in a stated value or characteristic.

Embodiments of this disclosure includes devices, systems, and methods for treating bodily wounds, e.g., endoluminal wounds, including the endoscopic delivery of a treatment aid. Examples of a treatment aid may include an adhesive or any suitable therapeutic agent, or a combination with an adhesive and a therapeutic agent. Said adhesive may be in the form of a patch, and said agent, in any suitable form, may be delivered via a patch. For example, the patch may be loaded with a therapeutic agent, and the patch may deliver the agent over time when in contact with tissue. Therefore, the patch may be configured to adhere to tissue and serve as a protective layer, and/or deliver agent to any bodily lumen, cavity, etc., for example, the GI tract.

The patch is not particularly limited. The patch may be a biodegradable and/or biocompatible patch of any suitable shape, e.g., a square, rectangle, etc., or any suitable dimension, e.g., <NUM> x <NUM>, depending on the treatment site. Moreover, the patch may be of any suitable material, e.g., polysaccharides (chitosan, cellulose, starch, alginates, etc.) that may be further modified with synthetic biocompatible materials (PGA, PLA, PCA, PEG, etc.) In some embodiments, the patch may be multi-layered, with each layer having different properties and characteristics to delay degradation over time. For example, each layer of a patch configured for agent delivery may comprise of a different ratio of natural/synthetic polymers to yield a timed release of the agent for an extended period of time. Thus, layers may degrade and the patch may continue to provide therapy.

The patch may be delivered via a catheter, scope (endoscope, bronchoscope, colonoscope, etc.), tube, or sheath, inserted into the GI tract via a natural orifice. The orifice can be, for example, the nose, mouth, or anus, and the placement can be in any portion of the GI tract, including the esophagus, stomach, duodenum, large intestine, or small intestine. <FIG>, further discussed below, illustrate embodiments of medical devices configured to deliver the patch to a lumen of the GI tract. It is noted that any one of these medical devices may be used with any suitable endoscope. For example, an endoscope may include a handle including a port, and the port may receive any one of the medical devices of <FIG>, which may extend distally via a working channel of the endoscope's shaft.

Referring to <FIG>, a medical device <NUM> includes an inner catheter <NUM>, an outer sheath <NUM>, and a delivery feature <NUM>. Inner catheter <NUM> may be any suitable, biocompatible catheter including at least one inner channel (not shown), as well as at least one opening (not shown) further discussed below. Inner catheter <NUM> includes a proximal end including a luer <NUM>, a distal end including a nose <NUM>, and a handle <NUM>. Luer <NUM> is not particularly limited, and may be any suitable luer configured to couple the proximal end of catheter <NUM> with a fluid source, so that the inner channel of catheter <NUM> may be in communication with said fluid source. The type of fluid is not particularly limited, and may be any suitable fluid, e.g., pressurized gas, saline. Nose <NUM> defines an atraumatic distal end of device <NUM>, and is conical in shape, but not limited thereto. Handle <NUM> is not particularly limited, and may be of any suitable shape or size that may be gripped by a user of device <NUM>. Handle <NUM> may be fixed to the outer surface of inner catheter <NUM>, between luer <NUM> and a proximal end <NUM> of outer sheath <NUM>.

Outer sheath <NUM> may be any suitable, biocompatible catheter configured to sheath a portion of inner catheter <NUM>, and in some instances, delivery feature <NUM> (further discussed below). Outer sheath <NUM> includes proximal end <NUM> including a handle <NUM>. Handle <NUM> is not particularly limited, and may be any suitable handle that is fixed to the outer surface of proximal end <NUM> or a proximal portion of sheath <NUM>. A user may grip handle <NUM> to retract outer sheath <NUM> proximally, relative to inner catheter <NUM>, thereby exposing delivery feature <NUM> to an external environment, e.g., a bodily lumen. Outer sheath <NUM> also includes a distal end <NUM>, which may abut nose <NUM> when outer sheath <NUM> is translated distally, relative to inner catheter <NUM>.

Referring to <FIG>, delivery feature <NUM> includes an expandable device, e.g., a balloon <NUM>, a patch <NUM>, and a connector <NUM>. Delivery feature <NUM> may include a number of states: <NUM>) a pre-deployment state, in which balloon <NUM> is in a deflated state (shown in <FIG>); <NUM>) a deployment state, in which balloon <NUM> is in an inflated state (shown in <FIG>); <NUM>) a post-deployment state, in which patch <NUM> is released from balloon <NUM>, and balloon <NUM> is ready to return to a deflated state (shown in <FIG>); and <FIG>) a withdrawal state (not shown), in which balloon <NUM> has been deflated, and device <NUM> may be withdrawn from the patient.

Balloon <NUM> may be an inflatable/deflatable feature of any suitable material, e.g., polymer, plastic, etc. The size and shape of balloon <NUM> is not particularly limited, and may be such that balloon <NUM>, in an inflated state, contacts or abuts the targeted bodily lumen, e.g., the esophagus, colon, etc. For example, balloon <NUM> may be <NUM> to <NUM> in diameter when inflated, similar to the dimensions of a typical human esophagus. Balloon <NUM> maybe a compliant balloon (inflated by volume rather than pressure), non-compliant, or semi-compliant.

Balloon <NUM> may be fitted over a distal portion <NUM> of inner catheter <NUM>, which may include at least one opening (not shown). Said at least one opening is in fluid communication with the inner channel of catheter <NUM>, which in turn is in communication with the fluid source. Thus, said at least one opening may serve as an outlet by which balloon <NUM> may be inflated with fluid or deflated. The number of openings is not particularly limited. In a deflated state (shown in <FIG>), balloon <NUM> may be tightly raveled or wound about distal portion <NUM>, thereby minimizing its radial profile relative to inner catheter <NUM>. In an inflated state (shown in <FIG>), balloon <NUM> may unravel and expand to a size that allows the balloon (and patch <NUM>) to contact the surrounding bodily lumen.

In some examples, a proximal end of balloon <NUM> or another aspect of inner catheter <NUM> may further include a pressure relief valve (not shown). Said pressure relief valve may be pre-set with a cut off pressure value, e.g., <NUM> psi (<NUM> pascal), thereby inhibiting over-inflation of balloon <NUM>. This helps to ensure that the body lumen is not perforated during the procedure. Device <NUM> may also include an additional vent, valve, or other structure by which fluid from balloon <NUM> may be released, thereby deflating balloon <NUM>.

Patch <NUM>, as discussed above, is not particularly limited. Patch <NUM> may be configured to adhere to tissue when in contact, and may also deliver agent to a bodily lumen of the GI tract. Patch <NUM> may be coupled to balloon <NUM>, via connector <NUM> further discussed below. In the pre-deployment state (<FIG>), patch <NUM> may be tightly wound and spiraled around balloon <NUM>, thereby minimizing the radial profile of delivery feature <NUM>. When balloon <NUM> is inflated to transition feature <NUM> into a deployment state (<FIG>), patch <NUM> may simultaneously unravel and expand with balloon <NUM>, so that patch <NUM> may contact and adhere to surrounding tissue. Patch <NUM> may cover all or only a circumferential portion of balloon <NUM> for treating less than a full circumference of a bodily lumen.

Connector <NUM> may be a sheet or an adhesive of any suitable material, e.g., paper, silicone, etc. According to the invention, connector <NUM> is folded into two halves - a first portion <NUM> and a second portion <NUM>. First portion <NUM> is adhered to an outer surface of balloon <NUM>, via any suitable adhesive means, e.g., soluble, insoluble adhesives. For example, said adhesive means may be an insoluble adhesive so that first portion <NUM> remains adhered to the outer surface of balloon <NUM>. In another example, said adhesive means may be a soluble adhesive so that connector <NUM> may detach from balloon <NUM> after a duration of time. A surface of second portion <NUM>, that is adjacent to a surrounding patch <NUM> while connector <NUM> remains folded, may be attached to patch <NUM>. Thus, connector <NUM> may serve as an intermediary connector between balloon <NUM> and patch <NUM>. Second portion <NUM> may be attached to patch <NUM> by any suitable dissolvable adhesive. For example, said adhesive may be a water-soluble adhesive, e.g., polyvinyl alcohol, etc. Thus, after inflation of balloon <NUM> and expansion of patch <NUM>, patch <NUM> may be released from connector <NUM>, via the dissolution of the adhesive between second portion <NUM> and patch <NUM> (shown in <FIG>). It is noted that connector <NUM> is not limited to the example discussed above. In some instances, connector <NUM> may be of a single adhesive or sheet, with one side adhered to balloon <NUM> and the other adhered to patch <NUM>.

Referring to <FIG>, an example of a method for delivery of patch <NUM> is further discussed. A user may introduce medical device <NUM> into a subject while delivery feature <NUM> is in a pre-deployment state, and outer sheath <NUM> is sheathing feature <NUM>. For example, medical device <NUM> may be introduced into the body of a subject via a natural orifice such as a mouth or anus. Medical device <NUM> may traverse through a tortuous natural body lumen of the subject, such as an esophagus, stomach, colon, etc. Medical device <NUM> may be delivered via a scope or any other suitable way. A user may direct/position the distal end of medical device <NUM> within a targeted bodily lumen, e.g., esophagus, colon, etc. A user may then translate outer sheath <NUM> proximally by pulling on handle <NUM>, thereby exposing delivery feature <NUM> to the lumen. A user may then supply fluid through inner catheter <NUM>, e.g., by turning on the fluid source, to supply fluid to balloon <NUM>, thereby inflating balloon <NUM> and transitioning feature <NUM> to a deployment state. Fluid may be supplied, for example, until balloon <NUM> and patch <NUM> contact the surrounding lumen. In some instances, this volume of fluid supplied may be determined according to the size of the lumen, or may be preset as a cutoff value for an associated pressure relief valve. Once patch <NUM> contacts and adheres to the surrounding lumen, patch <NUM> may be released naturally from connector <NUM> and balloon <NUM> via the dissolution of the dissolvable adhesive between connector <NUM> and patch <NUM>. The user may then deflate balloon <NUM> by any suitable means, and retract device <NUM> proximally until device <NUM> is removed from the subject.

Referring to <FIG>, another example of a delivery feature <NUM>' of device <NUM>' is shown. In this example, like reference numerals refer to similar features described above in connection to delivery feature <NUM>. Delivery feature <NUM>' includes connector <NUM>' and a wire <NUM>. Connector <NUM>' is similar to connector <NUM> of device <NUM> in many respects. However, second portion <NUM>' includes a plurality of openings <NUM>, arranged throughout a length of second portion <NUM>'. As shown in <FIG>, openings <NUM> may be linearly arranged. However, in other examples, openings <NUM> may be throughout connector <NUM>' in any suitable arrangement. Openings <NUM> may be of a sufficient width to receive wire <NUM>, so that patch <NUM> may be sutured onto second portion <NUM>' via wire <NUM>, as shown in <FIG>. Thus, patch <NUM> may be coupled to second portion <NUM>', without the use of an adhesive.

Wire <NUM> is not particularly limited, and may be any suitable wire-like feature, including suture material. Wire <NUM> may be of a length extending from a distal portion of device <NUM>' to a point that is proximal to proximal end <NUM> of outer sheath <NUM>. For example, a distal end of wire <NUM> may be secured under a heat shrink tube <NUM>, or any other suitable mechanism, e.g., a crimp, which may be distal to feature <NUM>' and fixed to catheter <NUM>. Heat shrink tube <NUM> is not particularly limited. A portion of wire <NUM> proximal to its distal end may be sewn through patch <NUM> and second portion <NUM>', coupling second portion <NUM>' to patch <NUM>. The remaining proximal portion of wire <NUM> may extend throughout the lumen of sheath <NUM>, and past proximal end <NUM> of sheath <NUM>. A proximal end of wire <NUM> may be secured or attached to a knob or switch <NUM>. Knob or switch <NUM> may be positioned on any portion of device <NUM>', e.g., handle <NUM>, proximal to sheath <NUM>, or may be separate from device <NUM>'. Knob or switch <NUM> may be configured to wind or pull wire <NUM> proximally, so that the distal end of wire <NUM> may be released from heat shrink <NUM> tube and removed from patch <NUM> and second portion <NUM>', thereby releasing patch <NUM> from connector <NUM>'. Alternatively, wire <NUM> may hang out of proximal end <NUM> of sheath <NUM> for a user to manually pull, without any intervening mechanical features. In other examples, delivery feature <NUM>' may include a plurality of wires <NUM>, sewn through patch <NUM> and second portion <NUM>'. The additional wires may further secure patch <NUM> onto second portion <NUM>'.

Medical device <NUM>' may be used in a similar manner as medical device <NUM>, except a user may pull wire <NUM> proximally to deploy patch <NUM> from connector <NUM>' and balloon <NUM>. Wire <NUM> may be pulled by any suitable means. In some examples, a user many actuate knob or switch <NUM> which winds wire <NUM> proximally, so that wire <NUM> may be removed from connector <NUM>'. In other examples, a user may manually pull on wire <NUM> to do the same.

It is noted suturing is not limited to coupling patch <NUM> onto connector <NUM>'. In other examples, additional aspects of the medical device <NUM>' may be sutured together as well. For example, delivery feature <NUM>', in a pre-deployment state, may be packaged or contained in a wrapper of any suitable, biocompatible material. Said wrapper may be sutured onto an outer surface of patch <NUM>, via a second wire. Thus, in addition to wire <NUM>, a second wire may extend proximally along the length of device <NUM>'. In such an example, device <NUM>' may be without outer sheath <NUM>, as delivery feature <NUM>' may be contained within the sutured wrapper. To expose delivery feature <NUM>', the second wire may be pulled proximally to remove the second wire, and release said wrapper from patch <NUM>.

Referring to <FIG>, another example of a delivery feature <NUM>" of device <NUM>" is shown. In this example, like reference numerals refer to similar features described above in connection to delivery features <NUM>, <NUM>'. Balloon <NUM> may be coupled to patch <NUM>, via a soluble adhesive <NUM>, e.g., polyvinyl alcohol. Adhesive <NUM> may be on all or a portion of an inner surface of patch <NUM>, or on all or a portion of an outer surface of balloon <NUM>. Thus, when delivery feature <NUM>" is exposed and in a deployment state, patch <NUM> may be released from balloon <NUM> as adhesive <NUM> dissolves. Thus, medical device <NUM>" may be used in the same manner as device <NUM>, as discussed above.

It is noted connectors <NUM>, <NUM>' and adhesive <NUM>, discussed above, extend along only a portion of balloon <NUM>. However, delivery features <NUM>, <NUM>' <NUM>" are not limited to a single connector <NUM>, <NUM>' or a single spot of adhesive <NUM>. In some examples, said features may have a plurality of their respective connectors <NUM>, <NUM>' or adhesive <NUM> at different radial and longitudinal positions throughout balloon <NUM>, for greater adherence with patch <NUM> to balloon <NUM>.

<FIG> show another exemplary medical device <NUM>, which may include any of the features of medical device <NUM>, <NUM>', <NUM>" discussed above. Medical device <NUM> includes an inner catheter <NUM> (which may be the same or similar to catheter <NUM>), an outer sheath <NUM> (which may be the same or similar to sheath <NUM>), a nose <NUM> (which may be the same or similar to nose <NUM>), and a delivery feature <NUM>. Delivery feature <NUM> includes a stent <NUM> and patch <NUM>.

Stent <NUM> is not particularly limited, and may be any suitable, bio-absorbable stent. Stent <NUM> may be of any flexible and elastic-like material, e.g., PLLA, so that stent <NUM> may expand to its default shape after being adjusted or manipulated. Stent <NUM> may be of a shape memory material. The size and shape of stent <NUM> is not limited, and may depend on the dimensions of the bodily lumen, e.g., esophagus, colon, etc., to be treated. For example, stent <NUM> may be of a sufficient size to apply a necessary degree of pressure against the surrounding walls of a bodily lumen, without causing a perforation. This may also reduce the likelihood of undesired migration of stent <NUM>. Furthermore, stent <NUM>, in an expanded, default state, may be of a sufficient width to enable the proximal retraction of inner catheter <NUM> and nose <NUM> through a lumen of stent <NUM>. As discussed above, patch <NUM> is not particularly limited, and may be wrapped or folded around stent <NUM> via any suitable manner. In some instances, patch <NUM> may be coupled to stent <NUM> in a manner that would allow for patch <NUM> to expand as stent <NUM> expands. It is noted that patch <NUM> may be of a sufficient size to fully cover stent <NUM> in its expanded, original state. This may also reduce risk of ripping patch <NUM> upon expansion of stent <NUM>. However, in some examples, patch <NUM> may cover only a circumferential portion of stent <NUM> for treating less than a full circumference of a bodily lumen.

Delivery feature <NUM> includes a pre-deployment state (shown in <FIG>) and a deployment state (shown in <FIG>). In a pre-deployment state, delivery feature <NUM> is sheathed by outer sheath <NUM>, and stent <NUM> is collapsed or compressed about a distal portion <NUM> of inner catheter <NUM>. Stent <NUM> may be compressed and patch <NUM> may be wrapped and folded around stent <NUM> to minimize the radial profile of feature <NUM>, thereby allowing feature <NUM> to be sheathed by outer sheath <NUM>. In some examples, patch <NUM> may be affixed to an axial portion of stent <NUM>, and wound around stent <NUM> until deployment. The manner in which patch <NUM> may be affixed is not particularly limited, and may be, for example, via a biodegradable adhesive, or a heat or solvent weld. In some other examples, patch <NUM> may be attached to the distal or proximal end of stent <NUM> at particular points around the circumference, where patch <NUM> is then folded and pleated, and wrapped around stent <NUM> as it is pulled taught to be loaded into outer sheath <NUM>. While sheathed, stent <NUM> may remain in a compressed state, due to the surrounding inner surfaces of sheath <NUM>. In a deployment state, delivery feature <NUM> may be exposed to a surrounding lumen when sheath <NUM> is translated proximally relative to catheter <NUM>. With the removal of any surrounding surfaces, stent <NUM>, given its flexible, elastic characteristic, may expand to its original shape. As stent <NUM> expands, patch <NUM> may also unfold simultaneously, while still covering stent <NUM>. It is noted that to maintain patch <NUM> on stent <NUM>, any of the connectors <NUM>, <NUM>' (and associated adhesive, wire <NUM>, etc.) may be used in delivery feature <NUM>. Stent <NUM> may degrade over time in the bodily lumen.

Claim 1:
A medical device (<NUM>, <NUM>', <NUM>", <NUM>), comprising:
a first tube (<NUM>);
a second tube (<NUM>) configured to sheath at least a portion of the first tube and configured to translate along a length of the first tube;
an expandable device (<NUM>) at a distal portion (<NUM>, <NUM>) of the first tube, the expandable device having a collapsed state and an expanded state;
a patch (<NUM>) surrounding at least a portion of an outer surface of the expandable device; and
a connector (<NUM>, <NUM>') for holding the patch to the expandable device when the second tube covers the patch and the expandable device and for releasing the patch from the expandable device after the second tube uncovers the patch and the expandable device,
characterized in that
the connector comprises a folded sheet forming a first half (<NUM>) and a second half (<NUM>) of the folded sheet, wherein the first half of the folded sheet is attached to the expandable device, and the second half of the folded sheet is attached to the patch.