ORGAN PROLAPSE AND OTHER APPLICATIONS

RELATED APPLICATIONS

[0001] The present application claims priority to and the benefit of United States patent application no. 62/932,634, “Expansile Devices for Treatment of Organ Prolapse and Other Applications” (filed November 8, 2019). The entirety of the foregoing application is incorporated herein by reference for any and all purposes.

TECHNICAL FIELD

[0002] The present disclosure relates to the field of expansile medical devices. BACKGROUND

[0003] Pelvic organ prolapse (POP) is a common medical condition among women defined as displacement of one or more pelvic organs into the vaginal space. Approximately 3% of women in the United States will have vaginal bulging symptoms secondary to POP.

For these women, symptomatic management options include surgical correction or vaginal pessaries.

[0004] Vaginal pessaries, removable silicone devices placed in the vagina to prevent displacement of vaginal walls and pelvic organs, are a cost-effective and low-risk conservative treatment option for women with POP and have been recommended as a first- line option for POP. Periodic removal of pessaries is necessary to maintain proper genital hygiene; this helps reduce the risk of complications from chronically indwelling device, including malodorous vaginal discharge, vaginal wall erosion, irritation, and bleeding.

[0005] There are many types of vaginal pessaries currently available; these are generally categorized into “space occupying” or “supportive” pessaries. Most pessaries need to be manually folded or bent for insertion into the vagina, either by the patient or by a trained clinician. For the more effective “space-occupying” type pessaries, self-insertion and removal is not possible, and patients must undergo pelvic examination and pessary cleaning every 2-3 months by a trained clinician. Patients using space-occupying pessaries are unable to have sexual intercourse with the device in place. In contrast, “supportive” type pessaries are able to be self-inserted and removed by patients. However, supportive pessaries are less effective for moderate-to-severe POP and the manual dexterity required for self-care may still preclude women from successfully using a pessary for POP. Removal and replacement of pessaries, even by an experienced clinician, can be a challenging process and stressful experience for women.

[0006] The disclosed technology addresses the need for an expandable, space-filling vaginal pessary that can be easily positioned in the vagina and removed by the patient as needed.

SUMMARY

[0007] In meeting the aforementioned needs, the present disclosure first provides expansile devices, comprising: a first hub and a second hub arranged along a major axis; one or more elongate beams connecting the first hub and the second hub, an elongate beam defining a length, a thickness, and a width, the one or more elongate beams being arranged so as to permit relative rotation between the first hub and the second hub, at least one of the one or more elongate beams defining a non-zero beam twist angle, the one or more elongate beams being arranged so as to give rise to the expansile device having a stable first state and a stable second state, the expansile device being convertible from the first state to the second state by effecting relative motion of the first hub and the second hub towards one another, the expansile device defining an axial dimension measured along the major axis, the expansile device defining a radial dimension measured radially to the major axis, and the axial dimension being greater in the stable first state than in the stable second state, and the radial dimension being greater in the second state than in the first state.

[0008] Also provided are methods, comprising converting an expansile device according to the present disclosure from the stable first state to the stable second state. As described elsewhere herein, the conversion can be performed by effecting relative motion between the first hub and the second hub so as to bring the hubs closer to one another.

[0009] Also provided are methods, the methods comprising delivering an expansile device according to the present disclosure into a patient in need thereof.

[0010] Further provided are methods of manufacture, comprising: assembling a first hub, a second hub, and one or more elongate beams to form an expansile device, the expansile device comprising the first hub and the second hub arranged along a major axis with the one or more elongate beams connecting the first hub and the second hub, the one or more elongate beams being arranged so as to permit relative rotation between the first hub and the second hub, at least one of the one or more elongate beams defining a non-zero beam twist angle, the one or more elongate beams being arranged so as to give rise to the expansile device having a stable first state and a stable second state, the expansile device being convertible from the first state to the second state by effecting relative motion of the first hub and the second hub towards one another, the expansile device defining an axial dimension measured along the major axis, the expansile device defining a radial dimension measured radially to the major axis, and the axial dimension being greater in the stable first state than in the stable second state, and the radial dimension being greater in the second state than in the first state.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0012] The present application is further understood when read in conjunction with the appended drawings. For the purpose of illustrating the subject matter, there are shown in the drawings exemplary embodiments of the subject matter; however, the presently disclosed subject matter is not limited to the specific methods, devices, and systems disclosed. In addition, the drawings are not necessarily drawn to scale.

[0013] FIG. 1 provides an exemplary illustration of the disclosed technology;

[0014] FIG. 2 provides an illustration of the bistable nature of the disclosed technology;

[0015] FIG. 3 provides an exemplary illustration of the disclosed technology;

[0016] FIG. 4 provides an exemplary illustration of the disclosed technology;

[0017] FIG. 5 provides an exemplary illustration of the disclosed technology in terms of a Kirchoff rod model;

[0018] FIG. 6 provides an exemplary illustration of a model of the disclosed technology;

[0019] FIG. 7 provides an exemplary illustration of a model of the disclosed technology; [0020] FIG. 8 provides an exemplary energy landscape for the disclosed technology, showing the bistable nature of the disclosed devices;

[0021] FIG. 9 provides an exemplary illustration of the disclosed technology, showing the evolution of strain energy in the structure;

[0022] FIG. 10 provides an exemplary illustration of the disclosed technology, showing the tailorable bistable nature of the disclosed devices;

[0023] FIG. 11 provides an exemplary illustration of the disclosed technology;

[0024] FIG. 12 provides exemplary fabrication techniques;

[0025] FIG. 13 provides exemplary testing methods;

[0026] FIG. 14 provides exemplary experimental verifications to verify the relationship between axial force and displacement.;

[0027] FIG. 15 provides exemplary experimental results showing the bistable behaviors of the disclosed devices;

[0028] FIG. 16 provides an exemplary illustration of the disclosed technology;

[0029] FIG. 17 illustrates connecting multiple unit cells of the disclosed technology

[0030] FIG. 18 provides an illustrative, non-limiting summary of the disclosed technology;

[0031] FIG. 19 illustrates an exemplary device in its initial state (shown as the bottom inset in this figure), in an intermediate state (center image in this figure), and in a deployed (expanded) state (top image in this figure);

[0032] FIG. 20 illustrates an exemplary hub and stem according to the present disclosure;

[0033] FIG. 21 provides a schematic of a beam used in the disclosed technology; and

[0034] FIG. 22 provides an exemplary device according to the present disclosure.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0035] The present disclosure may be understood more readily by reference to the following detailed description taken in connection with the accompanying figures and examples, which form a part of this disclosure. It is to be understood that this disclosure is not limited to the specific devices, methods, applications, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention.

[0036] Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. The term “plurality”, as used herein, means more than one. When a range of values is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. All ranges are inclusive and combinable, and it should be understood that steps may be performed in any order.

[0037] It is to be appreciated that certain features of the invention which are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. All documents cited herein are incorporated herein in their entireties for any and all purposes.

[0038] Further, reference to values stated in ranges include each and every value within that range. In addition, the term “comprising” should be understood as having its standard, open-ended meaning, but also as encompassing “consisting” as well. For example, a device that comprises Part A and Part B may include parts in addition to Part A and Part B, but may also be formed only from Part A and Part B.

[0039] Figures

[0040] The attached figures are illustrative only and do not serve to limit the present disclosure or the appended claims

[0041] FIG. 1 provides a view of an exemplary component according to the present disclosure, showing upper and lower hubs joined via various beams. As shown, a beam can include a half-twist along its length, in between the upper and lower hubs.

[0042] FIG. 2 provides an exemplary design strategy, showing changes in height (i.e., the distance between upper and lower hubs), hub rotation, and energy for a beam twist angle of 180°. [0043] FIG. 3 provides an exemplary component according to the present disclosure, with the various features of the component labeled. As shown, by twisting a beam, one can induce a bend-twist coupling.

[0044] FIG. 4 provides an overview of an exemplary method for modeling the deformation of the beams, by modeling beams as Kirchoff rods.

[0045] FIG. 5 provides a Kirchoff rod model, related to FIG. 4.

[0046] FIG. 6 provides a solution to the various differential equations that can be used to describe the behavior of a component according to the present disclosure.

[0100] FIG. 7 provides comparative energy landscapes for components having a beam twist angle of 0° (left panel) and 180° (right panel).

[0101] FIG. 8 provides an exemplary surface plot and an exemplary energy curve for a component undergoing beam twisting.

[0102] FIG. 9 provides a plot of energy density for bending and twist modes (K1 is U-shaped, K2 is flat and essentially zero, and x is upside-down U-shaped).

[0103] FIG. 10 provides critical beam twisting to bistability for a variety of beam twist angles.

[0104] FIG. 11 provides an image of additive manufacturing of hubs and beams

[0105] FIG. 12 provides images of direct ink write printing to form beams for prototype fabrication.

[0106] FIG. 13 provides representative images of exemplary components and an exemplary testing method.

[0107] FIG. 14 provides experimental results performed on an example device.

[0108] FIG. 15 provides further experimental results from an example device.

[0109] FIG. 16 provides an illustration of the various configurations achieved by an example device during twisting.

[0110] FIG. 17 provides an illustration of multiple unit cells (each cell being formed of an upper hub and a lower hub) assembled together. It should be understood, however, that a device can be assembled of three hubs, a bottom hub, a middle hub, and an upper hub, with beams connecting the bottom hub to the middle hub and beams connecting the upper hub to the middle hub.

[0111] FIG. 18 provides an overview and summary of the work presented herein. [0112] FIG. 19 provides illustrations of a device according to the present disclosure in a first stable state (left panel), an intermediate state in which a user has rotated one of the hubs, and a second stable state (right panel).

[0113] FIG. 20 provides an illustration of a bottom hub and a stem according to the present disclosure.

[0114] FIG. 21 provides a schematic view of an exemplary beam according to the present disclosure.

[0115] FIG. 22 provides a view of an exemplary device according to the present disclosure.

[0047] In one aspect, the present disclosure provides a vaginal pessary, a removable medical device used to prevent organ prolapse. Such a device can comprise a top and bottom circular disc each with a desired thickness, herein referred as “hubs,” with cavities around the circular perimeter of the hub such that a beam or strip can be inserted.

[0048] Elongate beams (which can be 3D-printed silicone strips) can be inserted in the cavities of the top and bottom hubs, connecting the hubs into a kirigami lantem-like structure. The unique design of the hubs interconnected with the strips allows for novel volumetric shape change without the use of complex hinges or joints.

[0049] The kirigami-inspired structure can initially take the shape of a narrow cylinder. (Such a shape can ease insertion of the device, in medical applications.) After applied force on the top face of the top hub, the structure converts to a flat and wide space filling device. The conversion can be reversible, although this is not a requirement, as the conversion can also be irreversible. The elastic strips can be twisted before insertion into the hubs such that there is an internal strain in each strip that in turn enables a unique “snap- through” behavior as the structure transitions between two stable states.

[0050] This behavior of the device exhibiting two stable configurations with some applied stimulus is referred to as bistability. By modulating the shape and composition of the beams connecting the top and bottom hubs, the transition between the two stable configurations of the device can be precisely tuned to fit the specific needs of the clinician and patient.

[0051] In some embodiments, the disclosed technology can include a stem extending from the center of the top face of the bottom hub and extending through a cavity in the top hub to improve alignment of the hubs when the structure is deformed. The stem can include recesses, or grooves, extending along the vertical length of the stem such that the top and bottom hubs have a tuned rotation when the kirigami-structure is deformed between the stable configurations. The inclusion of this stem with grooves can increase the axial and radial stiffness in each stable configuration. The beams can also have a variable cross- sectional area through the length of the strip, which enables the unique volumetric shape change shown in this disclosure.

[0052] It should be understood that a stem (in any embodiment of the disclosed technology) can be solid, but can also be tubular or otherwise have one or more passages extending therethrough, including porous or otherwise pervious materials. As an example, a stem can be tubular in configuration so as to allow passage of material (e.g., fluid) when a device is in either of its stable states. A stem can be elongate, but this is not a requirement, as a stem can be wider than it is long. A stem can also have a constant cross-section, but this too is not a requirement, as a stem can have a varying cross-sectional dimension (e.g., a prolate spheroid, tapered, spherical, faceted, or otherwise having a varying cross-sectional dimension). It should also be understood that any part of a device according to the present disclosure can be solid/impervious, but can also be porous or pervious.

[0053] Any part of a device according to the present disclosure can also nonbiodegradable, but this is not a requirement, as any part of a device according to the present disclosure can also be biodegradable. A device can also comprise one or more medicaments, e.g., an analgesic, a hormone treatment, and the like disposed therein or thereon. In such a manner, the disclosed devices can be used to treat prolapse and also function as drug delivery vehicles.

[0054] FIG. 19 shows the transition between the two stable states for a component according to the present disclosure. Initially, the kirigami-like structure takes the tall cylindrical shape as shown in the first (left) frame of FIG. 19. When applying a vertical downward force on the top hub, the structure begins to collapse and the elastic strips begin to extend outward, which is shown in the second (middle) frame of FIG. 19.

[0055] If the downward vertical force were to be removed in this transition period, the structure would return to the original, tall cylindrical shape. By continuing to apply the vertical force, the beams snap outward and the structure undergoes a rotation of the top hub such that the entire structure can collapse to the shape of the final (right) frame in FIG. 19. From the collapsed state shown in the right-hand panel of FIG. 19, a sufficient force pulling the top and bottom hub apart can applied to return the structure to the original tall shape.

[0056] FIG. 20 shows a bottom hub 2002 in greater detail, also showing a stem 2006 that runs to or even through a top hub (not shown). Evenly spaced cavities 2004 are included along the perimeter of the bottom hub such that the elastic strips (not shown, but described elsewhere herein) can be inserted.

[0057] The designed grooves in the stem are included to control the rotational behavior of the structure during the vertical deformation. The deformation path initially follows the downward path labeled “1” (e.g., via groove 2008) until the structure locks into position “2.” At position 2, the structure wants to rotate to continue the collapse of the device due to the internal strain in the interconnected strips. Upon a slight release of the applied vertical force, the structure follows the rotational path “3” (along groove 2010) and finally continues the collapse along path “4” and along groove 2012. In this state, the structure attains the flat and wide space filling shape shown in the right panel of FIG. 19. The top hub can be pulled vertically upward along path “5” (along groove 2012 and then groove 2014) such that the structure takes the original cylindrical shape again.

[0058] The unique technology disclosed can be used in a variety of other applications, including reconfigurable devices used in space applications. Reconfigurable satellites and solar arrays have gained traction in the aerospace industry as the desired final state of a such devices have a high surface area, but the desired volume for transporting the device should be minimized. Many of these reconfigurable space structures use complex hinges and joints to enable the desired shape change.

[0059] The disclosed structure can transition between a tall cylinder of minimized radius from the major axis of the expansible device to a flat shape with a maximized radius from the major axis of the expansible device, all without the use of complex mechanical hinges and joints. This unique volumetric bistable device is thus applicable to the medical industry as a pessary or stent, and can also be scaled up to be used in the aerospace or soft robotics industries.

[0060] Exemplary Embodiments

[0061] Embodiment 1. An expansile device, comprising: a first hub and a second hub arranged along a major axis; one or more elongate beams connecting the first hub and the second hub, an elongate beam defining a length, a thickness, and a width, the one or more elongate beams being arranged so as to permit relative rotation between the first hub and the second hub, at least one of the one or more elongate beams defining a non-zero beam twist angle, the one or more elongate beams being arranged so as to give rise to the expansile device having a stable first state and a stable second state, the expansile device being convertible from the first state to the second state by effecting relative motion of the first hub and the second hub towards one another, the expansile device defining an axial dimension measured along the major axis, the expansile device defining a radial dimension measured radially to the major axis, and the axial dimension being greater in the stable first state than in the stable second state, and the radial dimension being greater in the second state than in the first state.

[0062] FIG. 22 provides an exemplary device according to the present disclosure.

As shown, expansile device 2200 can include a first hub 2202 and a second hub 2206. Elongate beam 2204 connects first hub 2202 and second hub 2206.

[0063] As shown, elongate beam 2204 can be rectangular in cross-section, although this is not a requirement, as beam 2204 can be of non-rectangular cross section, e.g., polygonal, or even ovoid in cross section. An elongate beam can also define beam twist angle f2, which is the angle by which the end of the beam that is connected to the second hub is offset from a horizontal plane.

[0064] Beam twist angle f2 can be from about 0 to about 180°, or from about 5 to about 175°, or from about 10 to about 170°, or from about 15 to about 165°, or from about 20 to about 160°, or from about 25 to about 155°, or from about 30 to about 150°, or from about 35 to about 145°, or from about 40 to about 140°, or from about 45 to about 135°, or from about 50 to about 130°, or from about 55 to about 125°, or from about 60 to about 120°, or from about 65 to about 115°, or from about 70 to about 110°, or from about 75 to about 105°, or from about 80 to about 100°, or from about 85 to about 95°, or even about 90°.

[0065] An elongate beam can also define beam twist angle fΐ, which is the angle by which the end of the beam that is connected to the first hub is offset from a horizontal plane. Beam twist angle f2 can be from about 0 to about 180°, or from about 5 to about 175°, or from about 10 to about 170°, or from about 15 to about 165°, or from about 20 to about 160°, or from about 25 to about 155°, or from about 30 to about 150°, or from about 35 to about 145°, or from about 40 to about 140°, or from about 45 to about 135°, or from about 50 to about 130°, or from about 55 to about 125°, or from about 60 to about 120°, or from about 65 to about 115°, or from about 70 to about 110°, or from about 75 to about 105°, or from about 80 to about 100°, or from about 85 to about 95°, or even about 90°. Either one of fΐ and f2 can be zero degrees, although this is not a requirement.

[0066] As shown, device 2200 can include multiple elongate beams (not all of which are labeled) that connect the first hub and the second hub. All of the elongate beams can each have the same beam twist angle (at the first hub and/or at the second hub), although this is not a requirement. Put another way, two elongate beams can have different beam twist angles where they each connect to the second hub. Likewise, two elongate beams can have different beam twist angles where they each connect to the first hub.

[0067] Embodiment 2. The expansile device of Embodiment 1, wherein at least one of the first hub and the second hub is characterized as a disc, as an N-sided polygon, as conical, as hemispherical, as frustoconical, or any combination thereof.

[0068] A hub can include one or more slots, recesses, or other features configured to engage and/or retain a beam. A hub can also include tabs, ridges, or other engagement features. A hub and a beam can each include a complementary feature so as to facilitate engagement between one another. A device can include a locking feature (e.g., a screw, a snap, a tab-and-slot feature, a bayonet coupling, and the like) to secure the beam to a hub; a beam can also be bonded (e.g., via adhesive and/or ultrasonic welding) to a hub.

[0069] Embodiment 3. The expansile device of any one of Embodiments 1-2, wherein at least one of the one or more elongate beams defines a width that is greater than its thickness. This can be seen by reference to FIG. 21. It should be understood that a beam’s cross section need not be rectangular or otherwise polygonal. A beam’s cross-section can be ovoid or otherwise non-polygonal. A beam can have a constant cross section along its length, but this is not a requirement, as a beam can have a non-constant cross-section along its length. For example, a beam can have a comparatively large cross-section at its ends, and a comparatively small cross-section toward its center or middle.

[0070] Embodiment 4. The expansile device of Embodiment 3, wherein the cross- section defines a thickness to width ratio (as shown in FIG. 21) of from 0.1 to about 1, e.g., from about 0.1 to about 1, from about 0.2 to about 0.8, from about 0.3 to about 0.7, from about 0.4 to about 0.6, or even about 0.5.

[0071] Embodiment 5. The expansile device of any one of Embodiments 1-4, wherein at least one of the one or more elongate beams defines a ratio of length to thickness (as shown in FIG. 21) of from 10 to about 60, or from about 15 to about 55, or from about 20 to about 50, or from about 30 to about 45, or from about 35 to about 40, or even about 40.

[0072] Embodiment 6. The expansile device of any one of Embodiments 1-5, wherein at least a portion of the expansile device comprises a coating disposed thereon. The coating can be a soft or resilient material, e.g., silicone. Biocompatible and nonimmunoreactive coatings are considered especially suitable.

[0073] Embodiment 7. The expansile device of Embodiment 6, wherein the coating comprises silicone.

[0074] Embodiment 8. The expansile device of any one of Embodiments 1-7, wherein the expansile device is free of metal. Such embodiments are useful for subjects who may undergo MRI testing or be exposed to strong magnetic fields.

[0075] Embodiment 9. The expansile device of any one of Embodiments 1-8, further comprising a stem, the stem configured such that at least one of the first hub and the second hub is rotatable about the stem.

[0076] An example of such a device is provided in FIG. 19 and FIG. 20. As shown in those figures, a device according to the present disclosure can include a stem. The stem can be rotatably mounted to one or both hubs, although this is not a requirement. A stem can be anchored to one hub and can extend to or through the other hub.

[0077] As shown in FIG. 19, the stem can extend from the lower hub toward and then through the upper hub. A stem can also be freely-rotating between two hubs, i.e., it is not a requirement that the stem be anchored on one of the hubs.

[0078] Embodiment 10. The expansile device of Embodiment 9, wherein the stem extends along the major axis of the expansile device.

[0079] Embodiment 11. The expansile device of any one of Embodiments 9-10, wherein the stem comprises a groove that engages with at least one of the first or second hubs, the groove being configured to guide the motion of at least one of the first or second hubs about the stem. Such a stem is shown in FIG. 20.

[0080] FIG. 20 shows a bottom hub 2002 in greater detail, also showing a stem 2006 that runs to or even through a top hub (not shown). Evenly spaced cavities 2004 are included along the perimeter of the bottom hub such that the elastic strips (not shown, but described elsewhere herein) can be inserted. The designed grooves in the stem are included to control the rotational behavior of the structure during the vertical deformation. The deformation path initially follows the downward path labeled “1” (e.g., via groove 2008) until the structure locks into position “2.” At position 2, the structure wants to rotate to continue the collapse of the device due to the internal strain in the interconnected strips.

[0081] Upon a slight release of the applied vertical force, the structure follows the rotational path “3” (along groove 2010) and finally continues the collapse along path “4” and along groove 2012. In this state, the structure attains the flat and wide space filling shape shown in the right panel of FIG. 19. The top hub can be pulled vertically upward along path “5” (along groove 2012 and then groove 2014) such that the structure takes the original cylindrical shape again. A device can be configured to achieve and retain a state in the manner of a bail-point or retractable pen mechanism, whereby a hub rotates and follows a certain pathway along a stem.

[0082] Embodiment 12. The expansile device of Embodiment 11, wherein the groove is characterized as helical about the stem. Such a groove is shown by arrow 3 in FIG. 20

[0083] Embodiment 13. The expansile device of Embodiment 11, wherein the groove is characterized as circumferential about the stem.

[0084] Embodiment 14. The expansile device of Embodiment 11, wherein the groove is characterized as axial along the stem. Such a groove is shown by arrow 5 in FIG. 20

[0085] Embodiment 15. The expansile device of any one of Embodiments 9-14, wherein the stem is secured to at least one of the first hub and the second hub. Securing can be accomplished by, e.g., interference fit, adhesives, ultrasonic welding, sintering, melt bonding, and the like.

[0086] Embodiment 16. The expansile device of any one of Embodiments 1-15, wherein at least one of the one or more elongate beams defines a beam twist angle of from about 120 to about 225 degrees, e.g., from about 120 to about 225 degrees, from about 130 to about 215 degrees, from about 140 to about 205 degrees, from about 150 to about 195 degrees, from about 160 to about 185 degrees, or even about 170 degrees. (A beam twist angle is shown in FIG. 6.)

[0087] Embodiment 17. The expansile device of Embodiment 16, wherein at least one of the one or more of the elongate beams defines a beam twist angle of from about 150 to about 210 degrees. [0088] Embodiment 18. The expansile device of any one of Embodiments 1-17, wherein at least one of the one or more elongate beams is isotropic in composition.

[0089] Embodiment 19. The expansile device of any one of Embodiments 1-17, wherein at least one of the one or more elongate beams is non-isotropic in composition. As an example, a beam can be relatively stiffer at the ends and relatively more flexible towards its midpoint.

[0090] A beam can also be relatively flexible toward its ends and relatively stiffer toward its midpoint. A beam can also transition from a relatively stiff region (e.g., at one end) to a relatively flexible region (e.g., toward the other end) of the beam.

[0091] A beam can be formed of the same material along the entirety of its length, but a beam can also include two or more regions of different materials or of a material having a different composition. As an example, a beam can have a first region that includes a reinforcement material (e.g., glass fiber) present at a loading level X (e.g., X mg fiber/cm ³ of beam material) and a second region that includes the reinforcement material present at a loading 2X (i.e., 2X mg fiber/cm ³ of beam material). A beam can have a discrete transition between a first region (e.g., having reinforcement loaded at level X) and a second region (e.g., having a reinforcement loaded at level 2X), but the transition can also be gradual.

[0092] Embodiment 20. The expansile device of any one of Embodiments 1-17, wherein the expansile device comprises two elongate beams that differ from one another in composition, dimension, beam twist angle, or both.

[0093] Embodiment 21. The expansile device of any one of Embodiments 1-20, further comprising a cover configured to at least partially enclose one or more elongate beams, one or more hubs of the expansile device, or one or more elongate beams and one or more hubs of the expansile device.

[0094] A cover can be, e.g., a cylindrical or toroidal portion of material that acts to enclose some or all of the device. Such a cover can be stretchable, but can also be rigid, e.g., a plurality of slats or other structures that act to shield the device’s mechanism from the user. Such a cover is especially useful where the device may be deployed inside a subject, as the cover can act to reduce or prevent direct contact between the subject’s tissues and the beams and hubs of the device. The cover can also act to support a subject’s tissues, e.g., as the cover spans the space between the beams and/or hubs of a device. A cover can be of a material that is relatively soft to the touch, although this is not a requirement. A cover can also be a relatively slippery material so as to facilitate insertion, although this is not a requirement either.

[0095] A cover can be provided as a “condom” wrap that is flexible and conforms to both deployed and non-deploy ed device states. Such a cover would eliminate gaps between the beams of the device. As an example, in a device used as a pessary, the cover aids in preventing prolapsing tissue from advancing between any gaps in the device, e.g., gaps between beams. A cover can also serve to smooth out the edges of the device, in particular when it is not possible to create rounded comers on the elongate beams of the device.

[0096] Embodiment 22. The expansile device of Embodiment 21, wherein the cover is configured to be disposed between one or more elongate beams and the environment exterior to the one or more elongate beams.

[0097] Embodiment 23. The expansile device of any one of Embodiments 21-22, wherein the cover is characterized as a sheath.

[0098] Embodiment 24. A method, comprising converting an expansile device according to any one of Embodiments 1-23 from the stable first state to the stable second state. As described elsewhere herein, the conversion can be performed by effecting relative motion between the first hub and the second hub so as to bring the hubs closer to one another.

[0099] Embodiment 25. The method of Embodiment 24, wherein the converting is within a subject’s body. This may occur, e.g., when a device according to the present disclosure is used as a pessary.

[00100] Embodiment 26. The method of Embodiment 25, wherein the converting is performed in treatment of organ prolapse. Pelvic organ prolapse is considered an especially suitable condition for treatment with devices according to the present disclosure.

[00101] Embodiment 27. A method, the method comprising delivering an expansile device according to any one of Embodiments 1-23 into a patient in need thereof.

[00102] Embodiment 28. A method of manufacture, comprising: assembling a first hub, a second hub, and one or more elongate beams to form an expansile device, the expansile device comprising the first hub and the second hub arranged along a major axis with the one or more elongate beams connecting the first hub and the second hub, the one or more elongate beams being arranged so as to permit relative rotation between the first hub and the second hub, at least one of the one or more elongate beams defining a non-zero beam twist angle, the one or more elongate beams being arranged so as to give rise to the expansile device having a stable first state and a stable second state, the expansile device being convertible from the first state to the second state by effecting relative motion of the first hub and the second hub towards one another, the expansile device defining an axial dimension measured along the major axis, the expansile device defining a radial dimension measured radially to the major axis, and the axial dimension being greater in the stable first state than in the stable second state, and the radial dimension being greater in the second state than in the first state.