Occluder devices

Various aspects of the present disclosure are directed toward systems, methods, and apparatuses that include an occlusion device having a barrier member. The barrier member may include an enlargeable portion and a tail portion extending from the enlargeable portion. The enlargeable portion and the tail portion are releasably coupled to the delivery catheter such that the tail portion is radially unsupported and collapsible upon deployment.

FIELD

The present disclosure relates generally to implantable medical devices, and more specifically to implantable medical devices for occluding, inhibiting, or preventing material movement and/or fluid flow through tissue apertures or body lumens.

BACKGROUND

Endovascular embolization is a treatment for various diseases and conditions in which blood vessels or other vascular channels and body lumens are malformed, distended, and/or ruptured. Examples of such conditions include aneurysms, arteriovenous malformations, and certain oncological conditions, among others. Embolization can involve occluding or blocking the malformed regions or passageways to prevent blood flow to certain areas of the body such as, for example, a tumor or an aneurysm. In some examples, a certain vessel or passageway may be occluded to force and/or increase fluid flow through an adjacent vessel.

A number of occluding devices exist for the treatment of such conditions, some of which include coils, balloons, foam, plugs, and others. Such devices generally cut off blood supply to the affected area.

SUMMARY

Various examples relate to implantable medical devices and systems for occluding, inhibiting, or preventing material movement and/or fluid flow through tissue apertures or body lumens. In particular, various examples relate to an occlusion device or system including a barrier member having an enlargeable portion, an anchor feature, and a collapsible tail portion.

According to one example (“Example 1”), an occlusion system includes a delivery catheter. The delivery catheter has a proximal end, a distal end, a proximal portion, and a distal portion. The occlusion system also includes an occlusion device coupled to the delivery catheter. The occlusion device is in a reduced profile delivery configuration. The occlusion device includes a barrier member including a radially enlargeable portion, a tail portion extending from the enlargeable portion, an anchor feature arranged with the enlargeable portion of the barrier member, and a lumen. The lumen extends through the enlargeable portion and the anchor portion and is configured to receive the delivery catheter. The enlargeable portion and the tail portion are releasably coupled to the catheter such that the tail portion is radially unsupported and collapsible upon deployment from the delivery catheter.

According to another example (“Example 2”) further to Example 1, the anchor feature includes a support member coupled to the enlargeable portion of the barrier member. The support member is expandable from a delivery configuration to a deployed configuration.

According to another example (“Example 3”) further to any one of Examples 1 to 2, the tail portion of the barrier member is configured to be released from the delivery catheter upon application of a retraction force to the tail portion with the catheter.

According to another example (“Example 4”) further to any one of Examples 1 to 3, the tail portion is configured to plastically deform and neck down in diameter upon application of the retraction force on the tail portion prior to release of the tail portion from the catheter.

According to another example (“Example 5”) further to any one of Examples 1 to 4, the tail portion includes opposing, longitudinal creases configured to facilitate radial collapsing of the tail portion following release from the catheter.

According to another example (“Example 6”) further to any one of Examples 1 to 5, the tail portion is adhered to the catheter.

According to another example (“Example 7”) further to any one of Examples 1 to 6, the tail portion is formed of an elastomeric material. The tail portion is configured to constrict following release from the delivery catheter.

According to another example (“Example 8”) further to any one of Examples 1 to 7, a ratio of the outer diameter of the barrier member to the length of the barrier member is at least 1 to 10.

According to another example (“Example 9”) further to any one of Examples 1 to 8, the tail portion is configured to evert through the enlargeable portion during retraction of the catheter following deployment of the enlargeable portion.

According to another example (“Example 10”) further to any one of Examples 1 to 9, the anchor feature includes at least one of: adhesive, one or more barbs, and an expandable framework.

According to another example (“Example 11”) further to any one of Examples 1 to 10, the system also includes a balloon. The balloon is configured to expand the enlargeable portion from the delivery configuration to the deployed configuration upon inflation of the balloon.

According to another example (“Example 12”) further to any one of Examples 1 to 11, the system also includes a constraint. The constraint is configured to prevent expansion of the enlargeable portion prior to deployment.

According to another example (“Example 13”), an implantable medical device includes a barrier member. The barrier member includes a first end, a second end, an enlargeable portion configured to expand from a delivery configuration to a deployed configuration, a tail portion, a lumen extending from the first end to the second end, a length, and an outer diameter. The tail portion is configured to flatten against itself to form a seal. The implantable medical device also includes an anchor feature coupled to the barrier member at the enlargeable portion. The anchor feature is configured to expand with the barrier member from the delivery configuration to the deployed configuration.

According to another example (“Example 14”) further to Example 13, a ratio of the outer diameter of the barrier member to the length of the barrier member is at least 1 to 10.

According to another example (“Example 15”) further to any one of Examples 13 to 14, the anchor feature includes at least one of: adhesive, one or more barbs, and an expandable framework.

According to another example (Example 16″) further to any one of Examples 13 to 15, the anchor feature includes a support member. The support member has an expandable framework.

According to another example (“Example 17”) further to any one of Examples 13 to 16, the first end and the second end of the barrier member are substantially open while the enlargeable portion is in the delivery configuration.

According to another example (“Example 18”) further to any one of Examples 13 to 17, the second end of the barrier member is substantially closed while the enlargeable portion is in the deployed configuration.

According to another example (“Example 19”) further to any one of Examples 13 to 18, the tail portion of the barrier member is configured to evert upon expansion of the enlargeable portion to the deployed configuration.

According to another example (“Example 20”), a method of delivering an implantable medical device includes intraluminally delivering the system of any one of Examples 1 to 12 to a desired treatment site within a body lumen of a patient. The method also includes expanding the enlargeable portion of the barrier member to fit the body lumen.

DETAILED DESCRIPTION

Various aspects of the present disclosure relate to designs for implantable medical devices for occluding body lumens such as vasculature of a patient. The devices can be configured for partial (e.g., restricted flow), selective (e.g., valved flow), and/or total occlusion as desired. The term “occlusion,” as used herein, includes the partial, selective, and total occlusion. In addition, various aspects of the present disclosure relate to occlusion systems for occlusive treatment at a desired treatment location within the body of a patient, such as a body lumen of a patient. For reference, the term “body lumen” should be read to include any passage within the body of a patient that is capable of occlusion. In some examples, the occlusion system may include a delivery catheter and an occlusion device. The occlusion device may be self-expanding, expandable by application of an expansion force, or combinations thereof.

In certain instances, it may be beneficial to seal the body lumen rapidly and efficiently such as, for example, in large or high-flow vascular channels, to prevent further damage to the area or undesirable effects to the patient. Occlusion systems, according to the examples provided herein, can be advantageous in several respects, including the ability to be produced using efficient manufacturing processes and provide fast, secure, and reliable occlusion by effectuating device closure/sealing in response to the natural body pressure (e.g., blood pressure) within the body lumen.

In some examples, the occlusion systems discussed herein can also treat a wide range of body passages with a single device. In some examples, the occlusion systems permit guidewire access through both ends of the occlusion device without compromising luminal sealing, causing an inflow of bodily fluid, or otherwise interfering with efficacy. In some examples, the system permits one or more guidewires to remain in place during device delivery, after device delivery, and/or during and after occlusion device removal from the patient's body, reducing and/or eliminating the need for multiple devices and/or procedures.

FIG.1Ashows an occlusion system10including a delivery catheter12, an occlusion device14, and an optional guidewire16in a delivery configuration. The delivery catheter12is configured for delivering the occlusion device14to a desired location in a body of a patient. Examples of body passages in which the system10is employable include arteries, veins, airways, the gastrointestinal tract, the urinary tract, the biliary tract, left atrial appendages, walls of the heart, shunts, and other body passages, whether naturally or artificially formed.

As shown inFIG.1A, in some embodiments, the delivery catheter12has a proximal end18, a distal end20, a central longitudinal axis XL, a proximal portion19near the proximal end18, and a distal portion21near the distal end20. The delivery catheter12has a length suitable to reach a desired treatment location within the body of a patient for delivery of the device14to the desired treatment location. For example, the delivery catheter12may have a length from about 80 cm to about 140 cm. However, it should be understood that the delivery catheter12can have any length as desired depending on a variety of factors, including the desired treatment location. Although endoluminal delivery methods are generally described in association with the occlusion system10, the occlusion system10may also be used in laparoscopic methods and other surgical methods. The delivery catheter12can include conventional medical grade materials such as nylon, polyacrylamide, polycarbonate, polyethylene, polyformaldehyde, polymethylacrylate, polypropylene, polytetrafluoroethylene, polytrifluorochlorethylene, polyvinylchloride, polyurethane, elastomeric organosilicon polymers, Pebax® polyether block amide, and metals such as stainless steel and nitinol.

As shown inFIG.1A, the occlusion device14includes a barrier member30that is generally impermeable to fluid flow therethrough. The occlusion device14may also include an attachment element40capable of retaining the barrier member30within a body lumen. In some embodiments, the barrier member30is oriented along the central longitudinal axis XL and includes a length L (FIG.3A). In various examples, the barrier member30has a generally cylindrical cross-sectional configuration, having an inner diameter D1and an outer diameter D2(FIGS.7A and7B) when the occlusion device14is in the delivery configuration. The barrier member30may be in the form of a tubular sleeve or sheath. In some examples, the barrier member30is secured to the delivery catheter12, such as a body26of the delivery catheter12.

As discussed above, the attachment element40is configured to maintain the barrier member30against an inner wall60of the body lumen upon expansion of the barrier member30from the delivery configuration to the deployed configuration. In some embodiments, the attachment element40may be an anchor feature42, as shown inFIG.1B.

FIG.1Bis an example of the device14in an expanded, or deployed configuration. As further described, the device14is expandable between the delivery configuration and the deployed configuration. For example, the occlusion device14may be self-expanding, balloon-expandable, or combinations thereof. As shown, following deployment, the device14includes an enlargeable portion22, otherwise referred to as an engagement portion, having an inner diameter D1′ and an outer diameter D2′ (not shown) and a sealing portion, or tail portion24. As described in further detail below, the tail portion24has a central lumen that is configured to self-seal under body pressure. For example, the tail portion24is optionally formed of a flexible or compliant material as subsequently discussed and is configured to collapse under back-pressure external to the tail portion24. For example, fluid pressure on the upstream side of the attachment element40compresses the tail portion24into a flat or smashed configuration, sealing the barrier member30and preventing fluid flow therethrough.

FIGS.2A-Cshow various examples of anchor features, according to some embodiments. In some embodiments, the anchor feature42amay be, for example, a support member44, as shown inFIG.2A. The support member44includes a framework that is expandable upon application of a radial expansion force. For example, the support member44may be an expandable stent ring, a self-expanding stent, or a balloon expandable stent, among other things. In some embodiments, the support member44is expandable to a suitable size and/or shape to fit inside the body lumen at the desired treatment location. For example, the support member44may have a deployed diameter approximately equal to the inner diameter of the body lumen at the desired treatment location. The support member44may be formed of a variety of suitable and biocompatible materials such as various metallic and non-metallic materials, including shape-memory alloys, nitinol, stainless steels, expandable polymers, plastics, and other biocompatible metals.

FIG.2Bshows another embodiment of an anchor feature. The anchor feature42may also be, for example, a barb42b. As shown inFIG.2B, the barb42battaches to the inner wall of the body lumen and secures and/or seals the barrier member30at the desired treatment location. For example, the barb42bmay be any of a spike, spur, hook or other feature that catches the inner wall of the body lumen to secure the barrier member30at the desired treatment location.

In another example, shown inFIG.2C, the anchor feature42is an adhesive material42c, such as an adhesive strip or coating around an outer wall of the barrier member30. Upon expansion of the barrier member30, the adhesive material can adhere to an inner wall of the body lumen, thereby helping to secure and/or seal the barrier member30to the surrounding body lumen at the desired treatment location. In other embodiments, the enlargeable portion22of the barrier member30may simply comprise a stiffer or more rigid material, as compared to the tail portion24, such that the enlargeable portion22is capable of forming to the inner wall of the body lumen. From the foregoing, it should be understood that a variety of anchor features42are contemplated, and that a combination of the foregoing examples (e.g., adhesive, barb, and/or support member combinations) may also be implemented.

FIGS.3A-Bshow various examples of barrier members, according to some embodiments. In some embodiments, the barrier member30has a first end32, a second end34, a first portion33near the first end32, a second portion35near the second end34, and a lumen36extending from the first end32to the second end34along the central longitudinal axis XL. In some embodiments, the barrier member30is configured in a continuous, tubular or cylindrical shape as shown inFIG.3A. For example, the barrier member30may be extruded, wrapped, or otherwise formed as a continuous tube. In some embodiments, the barrier member30may comprise features to promote collapsing or flattening of the tail portion24. Such features may include, for example, creases, folds, seams, perforations, and laser cut lines, among other things. In some examples, the barrier member30may comprise one or more layers or sheets of material (e.g., film material) as shown inFIG.3B. For example, the barrier member30can include a first sheet38adhered to a second sheet39to form a pair of longitudinal seams and a lumen36. In other examples, the tail portion24of the barrier member30may include opposing, longitudinal creases to facilitate collapsing. As described in greater detail below, such an arrangement has lower resistance to collapsing under pressure (e.g., in comparison to a circular cross-section) and may facilitate more effective sealing.

In some examples, the length L of the barrier member30may be from about 5 cm to about 20 cm. However, the length may vary depending on a variety of factors, including the anatomy of the patient and the desired treatment location. The barrier member30may have an outer diameter D2suitable such that a ratio of the outer diameter D2to the length L is at least 1 to 10.

In one example, the barrier member30is elastomeric and configured to stretch. The barrier member30can comprise any suitable, expandable and biocompatible material. Examples of suitable materials include, for example, fluoropolymers (e.g., polytetrafluoroethylene), polyurethanes, polyether block amides, and various elastomeric organosilicone polymers such as polysiloxanes. In various examples, the barrier member30comprises a necking film formed of polytetrafluoroethylene, polyethylene, or other materials as desired. As described herein, the term “necking film” can be defined as a film or layer of material capable of deforming longitudinally and decreasing in cross-sectional area as a result of localized strain.

FIG.4shows a profile of a self-expanding occlusion system, according to some embodiments. In some embodiments, the occlusion system10may also include a constraint70, otherwise referred to as a sheath or a sleeve, configured to prevent the device14from self-expanding before deployment is desired. As shown, the barrier member30may be removably coupled to the delivery catheter12(e.g., the body26) at a first portion33and/or the first end32. In some embodiments, at least the first portion33and/or the first end32of the barrier member30is expandable from the delivery configuration to the deployed configuration.

FIG.5shows a profile of a balloon-expandable occlusion system, according to some embodiments. As shown, the balloon80is operably coupled to the body26of the delivery catheter12such that the balloon80is capable of being diametrically adjusted to an enlarged diameter. In some examples, the device14is removably coupled to the balloon80and is configured to expand upon inflation of the balloon80.

The balloon80may be located at any of a variety of locations along the body26of the catheter12, generally including any point between the proximal end18and the distal end20of the catheter12as desired. In some embodiments, the barrier member30is removably coupled to the balloon80at the first portion33or the first end32of the barrier member30, as shown inFIG.5. The barrier member30can be coupled to the balloon80at any location along the working length of the balloon80as desired.

The balloon80can comprise a material that is generally inelastic and allows the balloon80to expand to a desired diameter upon sufficient pressurization. The balloon80can be formed of any of a variety of suitable, biocompatible materials. For example, suitable materials include nylon, polyethylene, polyethylene terephthalate (PET), polycaprolactam, polyesters, polyethers, polyamindes, polyurethanes, polyimides, acrylonitrile butadiene styrene (ABS) copolymers, polyester/polyether block copolymers, ionomer resins, liquid crystal polymers, rigid rod polymers, polyurethanes, latex, and elastomeric organosilicone polymers such as polysiloxanes.

As shown inFIG.6, in some examples, at least a portion of the barrier member30is overlapped onto itself (e.g., during an eversion process). For example, the tail portion24of the barrier member30is optionally everted to define an overlapped portion25and an everted length of material. As shown, both the first end32and the second end34of the barrier member30are oriented in the same direction (e.g., toward the distal end20of the delivery catheter12). In some embodiments, the overlapped portion25may be shorter than the tail portion24. The tail portion24may have a length from about 7 cm to about 25 cm or from about 10 cm to about 21 cm. However, the tail portion24may have any length as desired, which may depend on the desired treatment location.

In some embodiments, the first end32or the tail portion24of the barrier member30is optionally coupled or adhered to the body26of the delivery catheter12near the distal end20of the delivery catheter12, allowing the first end32to be retracted proximally upon removal of the delivery catheter12from the patient's body. In some embodiments, the first end32or tail portion24is adhered to the delivery catheter12by way of an adhesive material (e.g., an adhesive strip on an inner wall of the lumen36of the barrier member30). However, the first end32or tail portion24can be coupled to the delivery catheter12in a variety of other ways such as, for example, friction fits, thermal bonding, anchors, fasteners or other types of attachment as desired.

In some embodiments, the first end32or tail portion24of the barrier member30is configured to detach from the delivery catheter12by application of tension or a retraction force to the catheter following expansion of the enlargeable portion22of the barrier member30. For example, the tail portion24may detach from the delivery catheter12upon retraction of the delivery catheter12from the patient's body. In some embodiments, the tail portion24of the barrier member30is configured to neck down or reduce in diameter during detachment from the delivery catheter12. For example, the tail portion24may elastically recover a reduced diameter, or stretch or lengthen during detachment from the delivery catheter12to plastically deform to a smaller diameter, creating a smaller diameter at the first end32than at the second end34.

In various examples, the tail portion24of the barrier member30is radially unsupported and is configured to collapse upon itself under pressure and close. The tail portion24may flatten or compress against itself under external pressure to create a seal. In some embodiments, the barrier member30flattens or compresses as a result of the fluid pressure (e.g., blood pressure) within the body lumen. For example, when deployed, the fluid pressure on a first side of the device14and exterior to the barrier member30, and specifically the tail portion24of barrier member30, may be higher than the fluid pressure on a second side of the device and within the barrier member30, causing the tail portion24of the barrier member30to flatten or compress against itself.

In some embodiments, the tail portion24may collapse longitudinally (e.g., by “scrunching”). In some embodiments, the tail portion24may collapse diametrically, such as when tubular (e.g.,FIG.3A). In some embodiments, the barrier member30may collapse radially by flattening. For example, when formed with two opposing sides or sheets (e.g.,FIG.3B) secured together at opposing seams, the first sheet39and second sheet41may readily flatten against one another to close the lumen36. As discussed above, the barrier member30may be creased, scored, pleated, folded, be formed with seams or otherwise treated to encourage repeatable collapse under pressure.

FIGS.7A-Dshow a method of delivering the occlusion device14to the desired treatment area. Although the method discussed herein includes a balloon-expandable system, the method can also be employed for self-expanding systems or other systems.

As shown inFIG.7A, the occlusion system10is introduced into the body of a patient and guided along a guidewire16to the desired treatment area within a body lumen62. As discussed above, the desired treatment area may be any of a vein, artery, gastrointestinal passageway, or other body passageway. The body lumen62includes an inner wall60having an inner diameter DL.

Once at the desired treatment location, at least the enlargeable portion22of the barrier member30is expanded from the delivery configuration (FIG.7A) to the deployed configuration (FIG.7B). As shown, the barrier member30and/or the anchor feature42are expanded via inflation of the balloon80. However, as discussed above, the barrier member30and/or the anchor feature42may also be self-expanding upon removal of the constraint70(FIG.4).

When in the deployed configuration, the barrier member30and the anchor feature42have deployed diameters approximately equal to the inner diameter DLof the body lumen62. In some embodiments, wherein the anchor feature42is a support member44, the support member44creates a pressure fit with the inner wall60of the body lumen62and maintains the barrier member30against the inner wall60. Although shown in use with the support member44, the system10can use a variety of anchor features42as described above. For example, the barrier member30can be maintained or attached to the inner wall60via barbs (FIG.2B) and/or other anchoring mechanisms such as adhesive material (FIG.2C).

The delivery catheter12is then retracted proximally from the body lumen62in the direction denoted by arrow A. In some embodiments, the second end34is pulled through the enlargeable portion22of the barrier member30and forms the tail portion24(FIG.7C) oriented in the proximal direction. For example, the barrier member30is optionally everted back through the overlapped portion25and the support member44to form the tail portion24. In some embodiments, the tail portion24is stretched and necked down or reduced in diameter as the delivery catheter12is retracted. In other embodiments, the tail portion24may neck down or reduce in diameter as the support member44is expanded from the delivery configuration to the deployed configuration. In yet other embodiments, the tail portion24flattens or compresses against itself to form a seal, as discussed above. The second end34or tail portion24of the barrier member30detaches from the delivery catheter12(e.g., via a shearing action between the deforming tail portion24and delivery catheter12) as the delivery catheter12is removed from the body lumen62with the second end34of the barrier member30subsequently closing to form a seal.

As shown inFIG.7C, the tail portion24is oriented in the opposite direction of fluid flow (denoted by arrow B) through the body lumen62(i.e., upstream of the support member44). As discussed above, the fluid pressure on the upstream side of the support member44compresses the tail portion24into a flat or smashed configuration as indicated inFIG.7D, sealing the barrier member30, preventing fluid flow therethrough and occluding the body lumen62.

FIGS.8A-Dillustrate another embodiment in which the barrier member30is not everted as part of assembly to the delivery catheter12. As shown, the barrier member30is similarly deployed but rather than everting the barrier member30to form the tail portion24via retraction of the delivery catheter12, the tail portion24is simply pulled, necked down, and released from delivery catheter12, after which the tail portion24is compressed by the blood pressure and self-seals.

FIG.8Ashows the occlusion system10introduced into the body of a patient and guided along a guidewire16to the desired treatment area within a body lumen62. As discussed above, the desired treatment area may be any of a vein, artery, gastrointestinal passageway, or other body passageway.

Once at the desired treatment location, at least the enlargeable portion22of the barrier member30is expanded from the delivery configuration (FIG.8A) to the deployed configuration (FIG.8B). As shown, the barrier member30and/or the anchor feature42are expanded via inflation of the balloon80. However, as discussed above, the barrier member30and/or the anchor feature42may also be self-expanding upon removal of the constraint70.

The delivery catheter12is then retracted proximally from the body lumen62in the direction denoted by arrow A. In some embodiments, the second end34remains in the proximal direction (FIG.8C). The tail portion24may then be stretched and necked down or reduced in diameter as the delivery catheter12is retracted through the barrier member30. In other embodiments, the tail portion24may neck down or reduce in diameter as the support member44is expanded from the delivery configuration to the deployed configuration. In yet other embodiments, the tail portion24flattens or compresses against itself to form a seal, as discussed above.

As shown inFIG.8C, the tail portion24is oriented in the opposite direction of fluid flow (denoted by arrow B) through the body lumen62(i.e., upstream of the support member44). As discussed above, the fluid pressure on the upstream side of the support member44compresses the tail portion24into a flat or smashed configuration as indicated inFIG.8D, sealing the barrier member30, preventing fluid flow therethrough and occluding the body lumen62.

FIGS.9-11Bshow an occlusion device, as describe in detail above, deployed at various desired treatment locations.FIG.9, for example, shows the occlusion device14employed within a body lumen of a patient, according to one embodiment. In such an example, the device14is used to occlude a hole, fenestration, or passageway (e.g., in a Fontan procedure) between a patient's heart H and inferior vena cava IVC.

In another example, shown inFIG.10, the device14can be used to occlude various passageways in the brain BR to, for example, bypass or occlude an aneurysm AN.

In another example, shown inFIG.11A, the device14can be used as an optional one-way valve. For example, the device14may be placed in a urinary tract UT (downstream of a patient's bladder BL) to mitigate and/or reduce the severity of certain conditions such as, for example, urinary incontinence. If fluid pressure drops on an upstream side of the device14, the tail portion24(oriented on the upstream side of the device14) may collapse upon itself and form a seal.

In another example, shown inFIG.11B, the device14can be used as a one-way relief valve for treating conditions such as hydrocephalus, in which cerebrospinal fluid builds up in the brain and must be occasionally relieved. In such examples, the device14may allow fluid flow in one direction (i.e., in the case of hydrocephalus, from a brain ventricle (BV) into the venous system (V)) if the fluid pressure on the upstream side of the device14exceeds the fluid pressure on the downstream side of the device14or the side of the device14in which the tail portion24is oriented. If fluid pressure on the downstream side of the device14exceeds pressure on the upstream side, the tail portion24may collapse upon itself and form a seal.

The examples that follow illustrate the performance of various designs consistent with the foregoing description. These examples should be read in an illustrative manner, and should no be read to limit the scope of the disclosure.

EXAMPLES

The following examples illustrate the correlation between everted tail length and amount of leakage for barrier members having varying diameters. The barrier members used in all examples had a starting length of 8 inches. The barrier members were comprised of ePTFE film capable of stretching and/or necking down from a starting diameter to a smaller, necked diameter upon eversion. After eversion, the barrier member was then placed inside of a plastic cylinder and the cylinder was filled with water to a pressure that simulated blood pressure in the human body. The barrier member was cut shorter after each sample run. For example, the barrier member was cut from 8 inches to 6 inches after the first sample run. Therefore, the same barrier member was used for each sample.

The effect of everted tail length on leakage was observed for a barrier member having an original diameter of 0.050 inches (0.127 cm). The various water pressures and respective everted tail lengths of each sample are denoted in Table 1 below.

As shown in Table 1, Samples 1 and 2 having an everted tail length of 8 inches (20.32 cm) and 6 inches (15.24 cm), respectively, exhibited no signs of visible leakage when subjected to a water pressure similar to that of blood pressure. Sample 3, having an everted tail length of 4 inches (10.16 cm), exhibited trace amounts of leakage. While Samples 4 and 5, having everted tail lengths of 3 inches (7.62 cm) and 2 inches (5.08 cm), respectively, exhibited slow to moderate leakage. Therefore, it was concluded that shorter everted tail lengths, specifically tail lengths of less than 4 inches (7.62 cm), exhibited a greater amount of leakage than longer everted tails.

The effect of everted tail length on leakage was observed for a barrier member having a diameter of 0.100 inches (0.254 cm). The various water pressures and respective everted tail lengths of each sample are denoted in Table 2 below.

As shown in Table 2, Sample 6 having an everted tail length of 6 inches (15.24 cm) exhibited slower leakage than Samples 7 and 8, having everted tail lengths of 4 inches (7.62 cm) and 2 inches (5.08 cm), respectively. Therefore, as concluded in Experiment 1, generally, longer everted tail lengths correlate to less and/or slower leakage and shorter everted tail lengths correlate to more and/or faster leakage.

When comparing Examples 1 and 2, it was concluded that a smaller diameter tube exhibited less leakage than a larger diameter tube having the same everted tail length. For example, Sample 2, having a diameter of 0.050 inches (0.127 cm) and a tail length of 6 inches (15.24 cm), exhibited less leakage than Sample 6, having the same tail length but a larger diameter of 0.100 inches (0.254 cm). Similarly, Examples 3 and 7 had the same tail length (4 inches), but Example 3 exhibited only trace amounts of leakage, while Example 7 exhibited moderate leakage.

As disclosed above, Examples 1 and 2 were conducted in a plastic cylinder with water used to simulate blood pressure. Since blood and other bodily fluids are generally more viscous than water, the everted tail is expected to leak less and/or slower than observed in Examples 1 and 2 above. Thus, samples where no leakage or only trace leakage was observed would be expected to ultimately occlude during use in the human body.

The invention of this application has been described above both generically and with regard to specific embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments without departing from the scope of the disclosure. Thus, it is intended that the embodiments cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.